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This panel provides information on past usage of this interatomic potential (IP) powered by the OpenKIM Deep Citation framework. The word cloud indicates typical applications of the potential. The bar chart shows citations per year of this IP (bars are divided into articles that used the IP (green) and those that did not (blue)). The complete list of articles that cited this IP is provided below along with the Deep Citation determination on usage. See the Deep Citation documentation for more information.
199 Citations (105 used)
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USED (definite) M. Khalkhali, A. Rajabpour, and F. Khoeini, “Thermal transport across grain boundaries in polycrystalline silicene: A multiscale modeling,” Scientific Reports. 2019. link Times cited: 21 USED (high confidence) H. Dong, Z. Fan, P. Qian, and Y. Su, “Exactly equivalent thermal conductivity in finite systems from equilibrium and nonequilibrium molecular dynamics simulations,” Physica E: Low-dimensional Systems and Nanostructures. 2022. link Times cited: 1 USED (high confidence) S. Yoo, B. Lee, and K. Kang, “Density functional theory study of the mechanical behavior of silicene and development of a Tersoff interatomic potential model tailored for elastic behavior,” Nanotechnology. 2021. link Times cited: 8 Abstract: Silicene, a graphene-like 2D material made from Si atoms, ha… read moreAbstract: Silicene, a graphene-like 2D material made from Si atoms, has been fabricated and studied for its promising applications in micro/nanoelectronics. For the reliable function of silicene devices, it is important to investigate silicene’s mechanical properties. In this study, the authors conducted density functional theory (DFT) simulations of mechanical tests of silicene and investigated the elastic modulus and mechanical response such as structural transformation. In addition, the authors optimized the Tersoff potential parameters using a gradient-based minimization with a grid search method in hyperdimensional parameter space, to match the DFT calculation results in the elastic regime. With the new parameter set, the elastic moduli of silicene in the zigzag (ZZ) and armchair (AC) directions were computed with molecular statics (MS) simulations and compared with those of other Si interatomic potential models and DFT results. In addition, uniaxial tensile tests along the ZZ and AC directions were performed to examine how far the Tersoff model is transferable with our new parameter set to describe the nonlinear mechanical behavior of silicene. The results of uniaxial tensile tests suggest that the angle penalty function in the Tersoff model needs to be modified and that the stress–strain curve predicted with this modification shows improvement compared to the original function. read less USED (high confidence) H. Wang et al., “The exceptionally high thermal conductivity after ‘alloying’ two-dimensional gallium nitride (GaN) and aluminum nitride (AlN),” Nanotechnology. 2020. link Times cited: 16 Abstract: Alloying is a widely employed approach for tuning properties… read moreAbstract: Alloying is a widely employed approach for tuning properties of materials, especially for thermal conductivity which plays a key role in the working liability of electronic devices and the energy conversion efficiency of thermoelectric devices. Commonly, the thermal conductivity of an alloy is acknowledged to be the smallest compared to the parent materials. However, the findings in this study bring some different points of view on the modulation of thermal transport by alloying. The thermal transport properties of monolayer GaN, AlN, and their alloys of Ga x Al1−x N are comparatively investigated by solving the Boltzmann transport equation (BTE) based on first-principles calculations. The thermal conductivity of Ga0.25Al0.75N alloy (29.57 Wm−1 K−1) and Ga0.5Al0.5N alloy (21.49 Wm−1 K−1) are found exceptionally high to be between AlN (74.42 Wm−1 K−1) and GaN (14.92 Wm−1 K−1), which violates the traditional knowledge that alloying usually lowers thermal conductivity. The mechanism resides in that, the existence of Al atoms reduces the difference in atomic radius and masses of the Ga0.25Al0.75N alloy, which also induces an isolated optical phonon branch around 18 THz. As a result, the scattering phase space of Ga0.25Al0.75N is largely suppressed compared to GaN. The microscopic analysis from the orbital projected electronic density of states and the electron localization function further provides insight that the alloying process weakens the polarization of bonding in Ga0.25Al0.75N alloy and leads to the increased thermal conductivity. The exceptionally high thermal conductivity of the Ga x Al1−x N alloys and the underlying mechanism as revealed in this study would bring valuable insight for the future research of materials with applications in high-performance thermal management. read less USED (high confidence) S. Nickabadi, R. Ansari, and S. Rouhi, “An atomistic-based finite element progressive fracture model for silicene nanosheets,” Acta Mechanica. 2020. link Times cited: 2 USED (high confidence) M. Settipalli and S. Neogi, “Theoretical Prediction of Enhanced Thermopower in n-Doped Si/Ge Superlattices Using Effective Mass Approximation,” Journal of Electronic Materials. 2019. link Times cited: 7 USED (high confidence) S. Das, S. Mojumder, T. Rakib, M. Islam, and M. Motalab, “Atomistic insights into mechanical and thermal properties of stanene with defects,” Physica B: Condensed Matter. 2019. link Times cited: 15 USED (high confidence) B. C. Mech, K. Koley, and J. Kumar, “The Understanding of SiNR and GNR TFETs for Analog and RF Application With Variation of Drain-Doping Molar Fraction,” IEEE Transactions on Electron Devices. 2018. link Times cited: 8 Abstract: The 1-D nanoribbon (NR) of monolayer materials has gained im… read moreAbstract: The 1-D nanoribbon (NR) of monolayer materials has gained immense interest due to their unique properties qualitatively distinct from their bulk properties and the demand for nanoscale applications. In this paper, the quantum transport properties of two most prominent 2-D materials, i.e., silicene NR (SiNR) and a graphene NR (GNR) tunnel field-effect transistor (TFET) with the effect of different dopant molar fractions in the drain region are studied numerically using nonequilibrium Green’s function formalism. In SiNR TFET, higher on-state current ( ${I}_{ \mathrm{\scriptscriptstyle ON}}$ ) is observed due to wider tunneling energy window and high transmission probability of carriers. In order to observe the effect of variation of doping density in the drain region, we have studied analog figures of merit such as the transconductance ( ${g}_{m}$ ), output resistance ( ${r}_{o}$ ), transconductance generation factor ( ${g}_{m}/{I}_{D}$ ), and the intrinsic gain ( ${g}_{m}{r}_{o}$ ) for different molar fractions. Similarly, we have evaluated the RF performance of the SiNR and GNR TFETs as a function of cutoff frequency ( ${f}_{T}$ ), gate capacitance ( ${C}_{G}$ ), and transport delay ( $\tau$ ). read less USED (high confidence) M. Noshin, A. I. Khan, and S. Subrina, “Thermal transport characterization of stanene/silicene heterobilayer and stanene bilayer nanostructures,” Nanotechnology. 2018. link Times cited: 18 Abstract: Recently, stanene and silicene based nanostructures with low… read moreAbstract: Recently, stanene and silicene based nanostructures with low thermal conductivity have incited noteworthy interest due to their prospect in thermoelectrics. Aiming at the possibility of extracting lower thermal conductivity, in this study, we have proposed and modeled stanene/silicene heterobilayer nanoribbons, a new heterostructure and subsequently characterized their thermal transport by using an equilibrium molecular dynamics simulation. In addition, the thermal transport in bilayer stanene is also studied and compared. We have computed the thermal conductivity of the stanene/silicene and bilayer stanene nanostructures to characterize their thermal transport phenomena. The studied nanostructures show good thermal stability within the temperature range of 100–600 K. The room temperature thermal conductivities of pristine 10 nm × 3 nm stanene/silicene hetero-bilayer and stanene bilayer are estimated to be 3.63 ± 0.27 W m−1 K−1 and 1.31 ± 0.34 W m−1 K−1, respectively, which are smaller than that of silicene, graphene and some other 2D monolayers as well as heterobilayers such as stanene/graphene and silicene/graphene. In the temperature range of 100–600 K, the thermal conductivity of our studied bilayer nanoribbons decreases with an increase in the temperature. Furthermore, we have investigated the dependence of our estimated thermal conductivity on the size of the considered nanoribbons. The thermal conductivities of both the nanoribbons are found to increase with an increase in the width of the structure. The thermal conductivity shows a similar increasing trend with the increase in the ribbon length, as well. Our results suggest that, the low thermal conductivity of our studied bilayer structures can be further decreased by nanostructuring. The significantly low thermal conductivity of the stanene/silicene heterobilayer and stanene bilayer nanoribbons realized in our study would provide a good insight and encouragement into their appealing prospect in the thermoelectric applications. read less USED (high confidence) G. Qin and M. Hu, “Thermal Transport in Phosphorene.,” Small. 2018. link Times cited: 31 Abstract: Phosphorene, a novel elemental 2D semiconductor, possesses f… read moreAbstract: Phosphorene, a novel elemental 2D semiconductor, possesses fascinating chemical and physical properties which are distinctively different from other 2D materials. The rapidly growing applications of phosphorene in nano/optoelectronics and thermoelectrics call for comprehensive studies of thermal transport properties. In this Review, based on the theoretical and experimental progresses, the thermal transport properties of single-layer phosphorene, multilayer phosphorene (nanofilms), and bulk black phosphorus are summarized to give a general view of the overall thermal conductivity trend from single-layer to bulk form. The mechanism underlying the discrepancy in the reported thermal conductivity of phosphorene is discussed by reviewing the effect of different functionals and cutoff distances on the thermal transport evaluations. This Review then provides fundamental insight into the thermal transport in phosphorene by reviewing the role of resonant bonding in driving giant phonon anharmonicity and long-range interactions. In addition, the extrinsic thermal conductivity of phosphorene is reviewed by discussing the effects of strain and substrate, together with phosphorene based heterostructures and nanoribbons. This Review summarizes the progress of thermal transport in phosphorene from both theoretical calculations and experimental measurements, which would be of significance to the design and development of efficient phosphorene based nanoelectronics. read less USED (high confidence) H. Xie, X. Gu, and H. Bao, “Effect of the accuracy of interatomic force constants on the prediction of lattice thermal conductivity,” Computational Materials Science. 2017. link Times cited: 16 USED (high confidence) Z. Wang and X. Ruan, “On the domain size effect of thermal conductivities from equilibrium and nonequilibrium molecular dynamics simulations,” Journal of Applied Physics. 2017. link Times cited: 31 Abstract: Equilibrium molecular dynamics (EMD) simulations with the Gr… read moreAbstract: Equilibrium molecular dynamics (EMD) simulations with the Green-Kubo formula and nonequilibrium molecular dynamics (NEMD) simulations with the Fourier's Law are two widely used methods for calculating thermal conductivities of materials. It is well known that both methods suffer from domain size effects, especially for NEMD. But the underlying mechanisms and their comparison have not been much quantitatively studied before. In this paper, we investigate their domain size effects by using crystalline silicon at 1000 K, graphene at 300 K, and silicene at 300 K as model material systems. The thermal conductivity of silicon from EMD simulations increases normally with the increasing domain size and converges at a size of around 4×4×4 nm3. The converging trend agrees well with the wavelength-accumulated thermal conductivity. The thermal conductivities of graphene and silicene from EMD simulations decrease abnormally with the increasing domain size and converge at a size of around 10×10 nm2. We ascribe the anom... read less USED (high confidence) A. Feyzi and R. Chegel, “Heat capacity, electrical and thermal conductivity of
silicene,” The European Physical Journal B. 2016. link Times cited: 29 USED (high confidence) M. Cherukara et al., “Ab Initio-Based Bond Order Potential to Investigate Low Thermal Conductivity of Stanene Nanostructures.,” The journal of physical chemistry letters. 2016. link Times cited: 71 Abstract: We introduce a bond order potential (BOP) for stanene based … read moreAbstract: We introduce a bond order potential (BOP) for stanene based on an ab initio derived training data set. The potential is optimized to accurately describe the energetics, as well as thermal and mechanical properties of a free-standing sheet, and used to study diverse nanostructures of stanene, including tubes and ribbons. As a representative case study, using the potential, we perform molecular dynamics simulations to study stanene's structure and temperature-dependent thermal conductivity. We find that the structure of stanene is highly rippled, far in excess of other 2-D materials (e.g., graphene), owing to its low in-plane stiffness (stanene: ∼ 25 N/m; graphene: ∼ 480 N/m). The extent of stanene's rippling also shows stronger temperature dependence compared to that in graphene. Furthermore, we find that stanene based nanostructures have significantly lower thermal conductivity compared to graphene based structures owing to their softness (i.e., low phonon group velocities) and high anharmonic response. Our newly developed BOP will facilitate the exploration of stanene based low dimensional heterostructures for thermoelectric and thermal management applications. read less USED (high confidence) X. Yuan, G. Lin, and Y. Wang, “Mechanical properties of armchair silicene nanoribbons with edge cracks: a molecular dynamics study,” Molecular Simulation. 2016. link Times cited: 13 Abstract: Silicene has been proven to be a promising material with att… read moreAbstract: Silicene has been proven to be a promising material with attractive electronic properties. During the synthesis of silicene, structural defects such as edge crack are likely to be generated and such defects in silicene have impacts on its properties. Herein, molecular dynamics simulations were performed to investigate the mechanical properties of the armchair silicene nanoribbons (ASiNRs) with edge cracks. Our results showed that the mechanical properties of the ASiNRs decrease because of the existence of edge crack. Both the pristine ASiNRs and the ASiNRs with edge cracks show brittle fracture behaviours. The crack length plays an important role in determining the critical strain and fracture strength of the ASiNRs. Moreover, we investigated the effects of strain rate and temperature on the mechanical properties of the ASiNRs with edge cracks. We observed that the increasing strain rate increases the critical strain and fracture strength while decreasing the Young’s modulus. Low-strain rates also changes the expanded directions of cracks in the ASiNRs. We also found that the increasing temperature could significantly decrease the mechanical properties of the ASiNRs with edge cracks. read less USED (high confidence) Y. Han, G. Qin, C. Jungemann, and M. Hu, “Strain-modulated electronic and thermal transport properties of two-dimensional O-silica,” Nanotechnology. 2016. link Times cited: 17 Abstract: Silica is one of the most abundant materials in the Earth’s … read moreAbstract: Silica is one of the most abundant materials in the Earth’s crust and is a remarkably versatile and important engineering material in various modern science and technology. Recently, freestanding and well-ordered two-dimensional (2D) silica monolayers with octahedral (O-silica) building blocks were found to be theoretically stable by (Wang G et al 2015 J. Phys. Chem. C 119 15654–60). In this paper, by performing first-principles calculations, we systematically investigated the electronic and thermal transport properties of 2D O-silica and also studied how these properties can be tuned by simple mechanical stretching. Unstrained 2D O-silica is an insulator with an indirect band gap of 6.536 eV. The band gap decreases considerably with bilateral strain up to 29%, at which point a semiconductor–metal transition occurs. More importantly, the in-plane thermal conductivity of freestanding 2D O-silica is found to be unusually high, which is around 40 to 50 times higher than that of bulk α-quartz and more than two orders of magnitude higher than that of amorphous silica. The thermal conductivity of O-silica decreases by almost two orders of magnitude when the bilateral stretching strain reaches 10%. By analyzing the mode-dependent phonon properties and phonon-scattering channel, the phonon lifetime is found to be the dominant factor that leads to the dramatic decrease of the lattice thermal conductivity under strain. The very sensitive response of both band gap and phonon transport properties to the external mechanical strain will enable 2D O-silica to easily adapt to the different environment of realistic applications. Our study is expected to stimulate experimental exploration of further physical and chemical properties of 2D silica systems, and offers perspectives on modulating the electronic and thermal properties of related low-dimensional structures for applications such as thermoelectric, photovoltaic, and optoelectronic devices. read less USED (high confidence) Y. Han and M. Hu, “Ground state of bilayer hα-silica: mechanical and electronic properties,” Nanotechnology. 2015. link Times cited: 7 Abstract: The family of two-dimensional (2D) crystals was recently joi… read moreAbstract: The family of two-dimensional (2D) crystals was recently joined by silica, one of the most abundant resources on earth. So far two different polymorphs of this material, namely a tetrahedra-shaped monolayer and a fully saturated bilayer structure, have been synthesized on various metal substrates and their fascinating properties enable 2D silica to hold promise in nanoelectronic device applications. In this paper a new ground state of bilayer—AAr-stacking hα-silica—has been discovered by first principles calculations. The new structure is featured with a formation of Si–Si bonds between all sp3 hybridized SiO3 triangular pyramids, lying respectively in different silica layers, with an intrinsic rotational angle of about 12.5° along the out-of-plane Si–Si bond. Due to the doubled number of Si–Si bonds in the new structure, the system energy is lowered by nearly three times more than that reported recently in literature (0.8 eV) (Özçelik et al 2014 Phys. Rev. Lett. 112 246803), when compared with the single layer hα-silica. A mechanical property investigation shows that the AAr-stacking bilayer hα-silica possesses high in-plane stiffness and a negative Poisson’s ratio, which stems from the intrinsic rotational angle of the SiO3 triangular pyramids. Strikingly, the negative Poisson’s ratio evolves into positive at a critical tensile strain ϵ ≈ 1.2%. Such negative-to-positive evolvement is associated with the adaptation of the rotational angle to the applied strain and the structure transition into the nearby valley of the energy landscape. The detailed transition process has been thoroughly analyzed. The electronic properties of the new ground state are also calculated, along with their response to the external strain. Our new ground state structure introduces a new member to the family of 2D bilayer silica materials and is expected to facilitate experimental studies identifying the related structures and exploring further physical and chemical properties of nanoscale systems. read less USED (high confidence) Z. Wang, T. Feng, and X. Ruan, “Thermal conductivity and spectral phonon properties of freestanding and supported silicene,” Journal of Applied Physics. 2015. link Times cited: 73 Abstract: We conduct molecular dynamics (MD) simulations to study the … read moreAbstract: We conduct molecular dynamics (MD) simulations to study the thermal conductivity of freestanding silicene and silicene supported on an amorphous silicon dioxide (SiO2) substrate in the temperature range from 300 to 900 K. The results show that the thermal conductivity decreases with increasing temperature and that the presence of the SiO2 substrate results in a great reduction, up to 78% at 300 K, to the thermal conductivity of silicene. With atomic trajectories from equilibrium MD simulations, we perform spectral energy density analysis to compute the thermal conductivities, spectral phonon relaxation times, and spectral phonon mean free paths (MFPs) of freestanding and supported silicene at 300 K. When silicene is put on a SiO2 substrate, the phonon relaxation times are decreased from 1–13 ps to less than 1 ps, and the phonon MFPs are reduced from 10–120 nm to 0–20 nm. We also calculate the thermal conductivity contributions from all phonon branches and find that the thermal conductivities of freestanding and supported silicene are mainly (>85%) contributed by the longitudinal and transverse acoustic phonons, while the out-of-plane acoustic phonons have a contribution less than 3%. Our study predicts the reduction of the thermal conductivity of silicene due to substrate effects and provides a fundamental understanding of the reduction in terms of the spectral phonon relaxation times and MFPs. read less USED (low confidence) W. Zhao, S. Wang, L. Zhou, and X. Du, “Reducing interfacial thermal resistance between polyethylene oxide-based solid-state polymer electrolyte and lithium anode by using IVA group two-dimensional materials: A molecular dynamics study,” International Journal of Heat and Mass Transfer. 2024. link Times cited: 0 USED (low confidence) A. Sharma, S. Sharma, and S. Ajori, “Molecular dynamics simulation of the mechanical and thermal properties of phagraphene nanosheets and nanotubes: a review,” Journal of Materials Science. 2023. link Times cited: 0 USED (low confidence) X. Wang et al., “Unexpectedly high thermoelectric performance of anisotropic Zr2Cl4 monolayer,” Journal of Physics: Condensed Matter. 2023. link Times cited: 0 Abstract: Recently, the Hf2Cl4-type materials as functional materials … read moreAbstract: Recently, the Hf2Cl4-type materials as functional materials have attracted broad interest because of their enormous potential in thermoelectric (TE) applications. However, relevant investigations are still scarce up to now. To explore the Hf2Cl4-type materials with excellent TE properties, we focus on the TE properties of Zr2Cl4 monolayer and calculate the TE parameters based on first-principles calculations and Boltzmann transport equation. Although, as compared to some typical TE materials, it exhibits better heat transport and thus higher lattice thermal conductivity, the figure of merits (ZT) of both p-type and n-type Zr2Cl4 reach an unexpectedly high value of 3.90 and 3.60, respectively, owing to the larger electrical conductivity and higher power factor. Additionally, owing to the prominent difference in electrical conductivity between the x- and y-direction, strong anisotropy in ZT values is observed. Our study reveals that both n-type and p-type Zr2Cl4 monolayers have the potential for future TE applications. read less USED (low confidence) S. S. P. Chowdhury, A. Samudrala, and S. Mogurampelly, “Modeling interlayer interactions and phonon thermal transport in silicene bilayers,” Physical Review B. 2023. link Times cited: 0 Abstract: We develop an accurate interlayer pairwise potential derived… read moreAbstract: We develop an accurate interlayer pairwise potential derived from the \textit{ab-initio} calculations and investigate the thermal transport of silicene bilayers within the framework of equilibrium molecular dynamics simulations. The electronic properties are found to be sensitive to the temperature with the opening of the band gap in the $\Gamma$$\rightarrow$M direction. The calculated phonon thermal conductivity of bilayer silicene is surprisingly higher than that of monolayer silicene, contrary to the trends reported for other classes of 2D materials like graphene and hBN bilayers. This counterintuitive behavior of the bilayer silicene is attributed to the interlayer interaction effects and inherent buckling, which lead to a higher group velocity in the LA$_1$/LA$_2$ phonon modes. The thermal conductivity of both the mono- and bilayer silicene decreases with temperature as $\kappa\sim T^{-0.9}$ because of the strong correlations between the characteristic timescales of heat current autocorrelation function and temperature ($\tau\sim T^{-0.75}$). The mechanisms underlying phonon thermal transport in silicene bilayers are further established by analyzing the temperature induced changes in acoustic group velocity. read less USED (low confidence) M. Maździarz, “Transferability of interatomic potentials for silicene,” Beilstein Journal of Nanotechnology. 2023. link Times cited: 1 Abstract: The ability of various interatomic potentials to reproduce t… read moreAbstract: The ability of various interatomic potentials to reproduce the properties of silicene, that is, 2D single-layer silicon, polymorphs was examined. Structural and mechanical properties of flat, low-buckled, trigonal dumbbell, honeycomb dumbbell, and large honeycomb dumbbell silicene phases, were obtained using density functional theory and molecular statics calculations with Tersoff, MEAM, Stillinger–Weber, EDIP, ReaxFF, COMB, and machine-learning-based interatomic potentials. A quantitative systematic comparison and a discussion of the results obtained are reported. read less USED (low confidence) G. Chen, B. Hu, Z.-liang Wang, and D. Tang, “First-Principles Investigation on Phonon Mode Conversion of Thermal Transport in Silicene Under Tensile Strain,” International Journal of Thermophysics. 2023. link Times cited: 0 USED (low confidence) W. Li and C.-C. Yang, “Suppressed Thermal Conductivity of Bilayer Sns: A Comparative Study Among the Monolayer, Bilayer and Bulk Sns,” SSRN Electronic Journal. 2023. link Times cited: 1 USED (low confidence) M. Kalantari and X. Zhang, “Thermal Transport in 2D Materials,” Nanomaterials. 2022. link Times cited: 5 Abstract: In recent decades, two-dimensional materials (2D) such as gr… read moreAbstract: In recent decades, two-dimensional materials (2D) such as graphene, black and blue phosphorenes, transition metal dichalcogenides (e.g., WS2 and MoS2), and h-BN have received illustrious consideration due to their promising properties. Increasingly, nanomaterial thermal properties have become a topic of research. Since nanodevices have to constantly be further miniaturized, thermal dissipation at the nanoscale has become one of the key issues in the nanotechnology field. Different techniques have been developed to measure the thermal conductivity of nanomaterials. A brief review of 2D material developments, thermal conductivity concepts, simulation methods, and recent research in heat conduction measurements is presented. Finally, recent research progress is summarized in this article. read less USED (low confidence) W. Li and C.-G. Yang, “Thermal transport properties of monolayer GeS and SnS: A comparative study based on machine learning and SW interatomic potential models,” AIP Advances. 2022. link Times cited: 5 Abstract: Phonon transport properties of two-dimensional materials can… read moreAbstract: Phonon transport properties of two-dimensional materials can play a crucial role in the thermal management of low-dimensional electronic devices and thermoelectric applications. In this study, both the empirical Stillinger–Weber (SW) and machine learning interatomic potentials are employed to investigate the lattice thermal conductivity of monolayer GeS and SnS through solving the phonon Boltzmann transport equation. The accuracy of the two types of interatomic potentials and their performance for the evaluation of thermal conductivity are verified by analyzing phonon harmonic and anharmonic properties. Our results indicate that the thermal conductivity can be predicted more accurately with a machine learning approach, while the SW potential gives rise to an overestimated value for both monolayers. In addition, the in-plane anisotropy of thermal transport properties existing in these monolayers can be confirmed by both potential models. Moreover, the origins of the deviation existing in calculated thermal conductivities, including both the effects of interatomic potential models and monolayer compositions, are elucidated through uncovering the underlying phonon transport mechanisms. This study highlights that in contrast to the machine learning approach, more careful verification is required for the simulation of thermal transport properties when empirical interatomic potential models are employed. read less USED (low confidence) T. Tran, T. Fang, and D.-Q. Doan, “Fracture mechanism and temperature/size-dependent thermal conductivity in gallium selenide monolayer,” Vacuum. 2022. link Times cited: 2 USED (low confidence) X.-L. Lü and H. Xie, “Thermal currents obtained and mutually switched by a modified Haldane model in graphene,” Communications in Theoretical Physics. 2022. link Times cited: 1 Abstract: By using the transfer matrix method, we discover three types… read moreAbstract: By using the transfer matrix method, we discover three types of current, such as the 100% spin-valley polarized current, pure spin-valley current and pure charge current, in a two-terminal graphene system. These types of current can be obtained and mutually switched by modulating the parameters of the modified Haldane model (MHM). In our work, these types of current are driven by the thermal bias. Compared with this method of increasing the one-lead temperature (with a fixed temperature difference), the thermal currents can be more effectively strengthened by increasing the temperature difference (with a fixed one-lead temperature). In order to rapidly turn off these currents, we choose to enhance the intensity of the off-resonant circularly polarized light instead of canceling the temperature difference. These results indicate that the graphene system with the MHM has promising applications in the spin and valley caloritronics. read less USED (low confidence) J. Zhou, H. Li, H.-K. Tang, L. Shao, K. Han, and X. Shen, “Phonon Thermal Transport in Silicene/Graphene Heterobilayer Nanostructures: Effect of Interlayer Interactions,” ACS Omega. 2022. link Times cited: 9 Abstract: Heterostructuring, as a promising route to optimize the phys… read moreAbstract: Heterostructuring, as a promising route to optimize the physical properties of 2D materials, has attracted great attention from the academic community. In this paper, we investigated the room-temperature in-plane and cross-plane phonon thermal transport in silicene/graphene van der Waals (vdW) heterostructures using molecular dynamics simulations. Our simulation results demonstrated that heat current along the graphene layer is remarkably larger than that along the silicene layer, which suggests that graphene dominates the thermal transport in silicene/graphene heterostructures. The in-plane phonon thermal conductivity of the silicene/graphene heterostructures could be a compromise between monolayer graphene and monolayer silicene. Heterostructuring can remarkably reduce the in-plane thermal conductivity of the graphene layer but increase the in-plane thermal conductivity of the silicene layer in heterobilayers compared with the freestanding monolayer counterparts because of their different structures. We also simulated the interlayer interaction strength effect on the in-plane phonon thermal conductivity and cross-plane interfacial thermal resistance of silicene/graphene heterostructures. Total in-plane phonon thermal conductivity and interfacial thermal resistance both decrease with the increase in the interlayer interaction strength in the silicene/graphene heterobilayers. In addition, the calculated interfacial thermal resistance shows the effect of the thermal transport direction across the interface. This study provides a useful reference for the thermal management regulation of 2D vdW heterostructures. read less USED (low confidence) A. Majumdar, S. Chowdhury, and R. Ahuja, “Drastic reduction of thermal conductivity in hexagonal AX (A = Ga, In & Tl, X = S, Se & Te) monolayers due to alternative atomic configuration,” Nano Energy. 2021. link Times cited: 13 USED (low confidence) Y. Tang, J. Che, and G. Qin, “On the microscopic view of the low thermal conductivity of buckling two-dimensional materials from molecular dynamics,” Chemical Physics Letters. 2021. link Times cited: 1 USED (low confidence) H. Qi, Z. Sun, N. Wang, G. Qin, H. Zhang, and C. Shen, “Two-dimensional Al2I2Se2: A promising anisotropic thermoelectric material,” Journal of Alloys and Compounds. 2021. link Times cited: 23 USED (low confidence) L. Cui, G. Wei, Z. Li, J.-M. Ma, and X. Du, “Coherent and incoherent effects of nanopores on thermal conductance in silicene,” International Journal of Thermal Sciences. 2021. link Times cited: 2 USED (low confidence) A. Islam, M. S. Islam, M. R. Islam, C. Stampfl, and J. Park, “Thermal transport in monolayer zinc-sulfide: effects of length, temperature and vacancy defects,” Nanotechnology. 2021. link Times cited: 5 Abstract: Of late, atomically thin two-dimensional zinc-sulfide (2D-Zn… read moreAbstract: Of late, atomically thin two-dimensional zinc-sulfide (2D-ZnS) shows great potential for advanced nanodevices and as a substitute to graphene and transition metal di-chalcogenides owing to its exceptional optical and electronic properties. However, the functional performance of nanodevices significantly depends on the effective heat management of the system. In this paper, we explored the thermal transport properties of 2D-ZnS through molecular dynamics simulations. The impact of length, temperature, and vacancy defects on the thermal properties of 2D-ZnS are systematically investigated. We found that the thermal conductivity (TC) rises monotonically with increasing sheet length, and the bulk TC of ∼30.67 W mK−1 is explored for an infinite length ZnS. Beyond room temperature (300 K), the TC differs from the usual 1/T rule and displays an abnormal, slowly declining behavior. The point vacancy (PV) shows the largest decrease in TC compared to the bi vacancy (BV) defects. We calculated phonon modes for various lengths, temperatures, and vacancies to elucidate the TC variation. Conversely, quantum corrections are used to avoid phonon modes’ icing effects on the TC at low temperatures. The obtained phonon density of states (PDOS) shows a softening and shrinking nature with increasing temperature, which is responsible for the anomaly in the TC at high temperatures. Owing to the increase of vacancy concentration, the PDOS peaks exhibit a decrease for both types of defects. Moreover, the variation of the specific heat capacity and entropy with BV and PV signify our findings of 2D-ZnS TC at diverse concentrations along with the different forms of vacancies. The results elucidated in this study will be a guide for efficient heat management of ZnS-based optoelectronic and nano-electronic devices. read less USED (low confidence) M. Noshin, A. I. Khan, R. Chakraborty, and S. Subrina, “Modeling and computation of thermal and optical properties in silicene supported honeycomb bilayer and heterobilayer nanostructures,” Materials Science in Semiconductor Processing. 2021. link Times cited: 8 USED (low confidence) A. Taheri, S. Pisana, and C. V. Singh, “Importance of quadratic dispersion in acoustic flexural phonons for thermal transport of two-dimensional materials,” Physical Review B. 2021. link Times cited: 18 Abstract: Solutions of the Peierls-Boltzmann transport equation using … read moreAbstract: Solutions of the Peierls-Boltzmann transport equation using inputs from density functional theory calculations have been successful in predicting the thermal conductivity in a wide range of materials. In the case of two-dimensional (2D) materials, the accuracy of this method can depend highly on the shape of the dispersion curve for flexural phonon (ZA). As a universal feature, very recent theoretical studies have shown that the ZA branch of 2D materials is quadratic. However, many prior thermal conductivity studies and conclusions are based on a ZA branch with linear components. In this paper, we systematically study the impact of the long-wavelength dispersion of the ZA branch in graphene, silicene, and $\ensuremath{\alpha}$-nitrophosphorene to highlight its role on thermal conductivity predictions. Our results show that the predicted $\ensuremath{\kappa}$ value, its convergence and anisotropy, as well as phonon lifetimes and mean free path can change substantially even with small linear to pure quadratic corrections to the shape of the long-wavelength ZA branch. Also, having a pure quadratic ZA dispersion can improve the convergence speed and reduce uncertainty in this computational framework when different exchange-correlation functionals are used in the density functional theory calculations. Our findings may provide a helpful guideline for more accurate and efficient thermal conductivity estimation in mono- and few-layer 2D materials. read less USED (low confidence) M. Rahman et al., “Phonon thermal conductivity of the stanene/hBN van der Waals heterostructure.,” Physical chemistry chemical physics : PCCP. 2021. link Times cited: 10 Abstract: We use classical non-equilibrium molecular dynamics (NEMD) s… read moreAbstract: We use classical non-equilibrium molecular dynamics (NEMD) simulations to investigate the phonon thermal conductivity (PTC) of hexagonal boron nitride (hBN) supported stanene. At first, we examine the length dependent PTCs of bare stanene and hBN, and the stanene/hBN heterostructure and realize the dominance of the hBN layer to dictate the PTC in the heterostructure system. Afterward, we assess the length-independent bulk PTCs of these materials. The bulk PTCs at room temperature are found as ∼15.20 W m-1 K-1, ∼550 W m-1 K-1, and ∼232 W m-1 K-1 for bare stanene and hBN, and stanene/hBN, respectively. Moreover, our simulations reveal that bare stanene exhibits a substantially lower PTC compared to bare hBN, and the predicted PTC of stanene/hBN lies between those of stand-alone stanene and hBN. We also found that the PTC obtained for the stanene/hBN system from NEMD simulations nicely agrees with the theoretical formula developed to predict the PTC of heterostructures of two distinct materials. Temperature studies suggest that the PTC of the stanene/hBN heterostructure system follows a decreasing trend with increasing temperature. Additionally, corresponding phonon density of states (PDOS) and phonon dispersion data are provided to comprehensively understand the phonon properties of bare stanene and hBN, and stanene/hBN. Overall, this NEMD study would offer a deep understating towards the PTC of the stanene/hBN heterostructure and would widen the scope of its successful operations in future nanoelectronic, spintronic, and thermoelectric devices. read less USED (low confidence) M. Rahman, E. Chowdhury, M. Shahadat, and M. Islam, “Engineered defects to modulate the phonon thermal conductivity of Silicene: A nonequilibrium molecular dynamics study,” Computational Materials Science. 2021. link Times cited: 15 USED (low confidence) M. Rahman, E. Chowdhury, D. A. Redwan, and S. Hong, “Computational characterization of thermal and mechanical properties of single and bilayer germanene nanoribbon,” Computational Materials Science. 2021. link Times cited: 13 USED (low confidence) N. Gupta and R. Verma, “First-principles study of thermoelectric transport properties in low-buckled monolayer silicene,” Physica B-condensed Matter. 2021. link Times cited: 12 USED (low confidence) M. Rahman, E. Chowdhury, D. A. Redwan, S. Mitra, and S. Hong, “Characterization of the mechanical properties of van der Waals heterostructures of stanene adsorbed on graphene, hexagonal boron-nitride and silicon carbide.,” Physical chemistry chemical physics : PCCP. 2021. link Times cited: 7 Abstract: Stanene has revealed a new horizon in the field of quantum c… read moreAbstract: Stanene has revealed a new horizon in the field of quantum condensed matter and energy conversion devices but its significantly lower tensile strength limits its further applications and effective operation in these nanodevices. Van der Waals heterostructures have given substantial flexibility to integrate different two-dimensional (2D) layered materials over the past few years and have proven highly functional with exceptional features, appealing applications, and innovative physics. Considerable efforts have been made for the preparation, thorough understanding, and applications of van der Waals heterostructures in the fields of electronics and optoelectronics. In this paper, we have executed Molecular Dynamics (MD) simulations to predict the tensile strength of van der Waals heterostructures of stanene (Sn) adsorbed on graphene (Gr), hexagonal boron nitride (hBN), and silicon carbide (SiC) (Sn/Gr, Sn/hBN, and Sn/SiC, respectively) subjected to both armchair and zigzag directional loading at different strain rates for the first time, which has enticing applications in electronic, optoelectronic, energy storage and bio-engineered devices. Among all the van der Waals heterostructures, the Sn/SiC heterostructure exhibits the lowest tensile strength and tensile strain. Furthermore, it has been found that zigzag directional loading could endure more tensile strain before fracture. Besides, it has been disclosed that though the rule of mixtures may accurately reproduce the Young's modulus of these heterostructures, it has limitations to predict the tensile strength. Fracture analysis suggests that for the Sn/hBN heterostructure the fracture initiates from the stanene layer while for the Sn/Gr and Sn/SiC heterostructures the fracture initiates from the Gr and SiC layer, respectively, for both armchair and zigzag directional loading. Overall, this study would aid in the design and efficient operation of Sn/Gr, Sn/hBN, and Sn/SiC heterostructures when subjected to mechanical force. read less USED (low confidence) E. Chowdhury, M. Rahman, S. Fatema, and M. Islam, “Investigation of the mechanical properties and fracture mechanisms of graphene/WSe2 vertical heterostructure: A molecular dynamics study,” Computational Materials Science. 2021. link Times cited: 22 USED (low confidence) M. El-Banna, A. H. Phillips, and A. Bayoumi, “Spin-valley thermoelectric characteristics of ferromagnetic silicene superlattice,” Ain Shams Engineering Journal. 2021. link Times cited: 5 USED (low confidence) M. I. Ahamed and N. Anwar, “Germanene,” Monoelements. 2020. link Times cited: 1 USED (low confidence) R. Chegel and M. Hasani, “Electronic and thermal properties of silicene nanoribbons: Third nearest neighbor tight binding approximation,” Chemical Physics Letters. 2020. link Times cited: 4 USED (low confidence) V.-T. Pham and T. Fang, “Effects of temperature and intrinsic structural defects on mechanical properties and thermal conductivities of InSe monolayers,” Scientific Reports. 2020. link Times cited: 14 USED (low confidence) Y. Yin, Y. Hu, C. Feng, S. Li, B. Li, and D. Li, “Strongly anisotropic thermal conductivity in planar hexagonal borophene oxide sheet,” Physics Letters A. 2020. link Times cited: 5 USED (low confidence) B. Shojaeverdi and E. Zaminpayma, “Influence of vacancy cluster on the electronic transport properties of silicene sheet,” Physica E-low-dimensional Systems & Nanostructures. 2020. link Times cited: 5 USED (low confidence) M. Barati, T. Vazifehshenas, T. Salavati-fard, and M. Farmanbar, “Competing effects of strain and vacancy defect on thermal conductivity of silicene: A computational study,” Computational Materials Science. 2020. link Times cited: 1 USED (low confidence) D. Han, W. Ding, X. Wang, and L. Cheng, “Tunable thermal transport in a WS2 monolayer with isotopic doping and fractal structure.,” Nanoscale. 2019. link Times cited: 15 Abstract: An emerging two-dimensional (2D) tungsten disulfide (WS2) ha… read moreAbstract: An emerging two-dimensional (2D) tungsten disulfide (WS2) has been attracting much attention due to its excellent physical properties. In this work, the thermal transports in isotopically doped WS2 monolayers modified with Rectangle Carpet (RC) and Sierpinski Carpet (SC) structures are investigated systematically using molecular dynamics simulations. The effects of fractal number and temperature on thermal conductivity (k) are evaluated. The SC fractal structures have lower thermal conductivities in comparison with the RC structures for each fractal number. Furthermore, an initial decreasing and then increasing trend of k is observed with increasing fractal number. We can also observe a negative correlation between k and temperature. The phonon dispersion, group velocity, participation ratio, spatial distribution of energy and phonon density of states are evaluated to reveal the thermal transport mechanism in WS2 monolayers. This work provides valuable information on phonon behavior to tune the thermal transport in 2D WS2 monolayers based thermoelectric applications. read less USED (low confidence) H. Alavi-Rad, A. Kiani-sarkaleh, S. Rouhi, and A. Ghadimi, “Variation of the electronic properties of the silicene nanosheet passivated by hydrogen atoms: A DFT investigation,” AIMS Materials Science. 2019. link Times cited: 2 Abstract: Using the first-principles calculations, the electronic prop… read moreAbstract: Using the first-principles calculations, the electronic properties of hydrogenated silicene (H-silicene) has been investigated. The influence of the hydrogenation on the bandgap and I-V characteristics of the silicene is evaluated. It is shown that the H-silicene has an indirect band gap, with the value of 2.33 eV while silicene nanosheet represents a semi-metallic behavior with a zero band gap and Dirac cone at the Fermi level. Some unique properties of H-silicene is observed which make it ideal for variety of applications in designing spintronic devices, optoelectronics devices, transparent conducting electrodes, and integrated circuits. read less USED (low confidence) S. M. Hatam-Lee, A. Rajabpour, S. Volz, and S. Volz, “Thermal conductivity of graphene polymorphs and compounds: From C3N to graphdiyne lattices,” Carbon. 2019. link Times cited: 47 USED (low confidence) Y. Wang, X. Yang, and Y. Shang, “Thermal transport properties in monolayer GeS,” Physics Letters A. 2019. link Times cited: 8 USED (low confidence) R. E. Roman and S. W. Cranford, “Defect sensitivity and Weibull strength analysis of monolayer silicene,” Mechanics of Materials. 2019. link Times cited: 10 USED (low confidence) V. V. Hoang and N. H. Giang, “Heating-induced phase transitions in confined amorphous tetra-silicene,” Materials Research Express. 2019. link Times cited: 2 Abstract: Heating-induced phase transitions of confined amorphous tetr… read moreAbstract: Heating-induced phase transitions of confined amorphous tetra-silicene (t-silicene) are studied via molecular dynamics (MD) simulations. Glassy models containing 6066 atoms interacted via Stillinger-Weber potential are heated up from 300 K to 5000 K at the heating rate of 1011 K s−1. We find glass-crystal-liquid phase transition indicated that amorphous t-silicene is a less stable glass. Crystallization of amorphous t-silicene occurs at around T X = 1290 K while subsequent melting of crystallized t-silicene appears at around T m = 1739 K. The latter is close to that of hexa-silicene. Thermodynamics and evolution of structure of models upon heating are analyzed in details. We find that crystallization of amorphous t-silicene occurs via homogeneous local rearrangements of atoms in the glassy matrix. Atomic mechanism of crystallization and subsequent melting of the obtained crystalline t-silicene is studied and the role of liquid-like atoms in this phase transition is clarified. read less USED (low confidence) L. Cui, S. Shi, Z. Li, G. Wei, and X. Du, “Reduction of thermal conductivity in silicene nanomesh: insights from coherent and incoherent phonon transport.,” Physical chemistry chemical physics : PCCP. 2018. link Times cited: 11 Abstract: Silicene nanomesh (SNM), a silicene sheet with periodically … read moreAbstract: Silicene nanomesh (SNM), a silicene sheet with periodically arranged nanoholes, has gained increasing interest due to its unique geometry and novel properties. In this paper, we have conducted molecular dynamics simulations to study the phonon transport properties of SNMs. The results demonstrate that the thermal conductivity of SNM, which is shown to be much lower than that of silicene, is little affected by temperature but can be effectively tuned by varying the porosity. To elucidate the underlying mechanisms for decreased thermal conductivity, we have investigated both coherent and incoherent phonon transport in SNMs. It is found that the phonon backscattering at the nanopore edges leads to extra thermal resistances. Additionally, the introduction of nanopores induces phonon localization and consequently hinders phonon transport in SNMs. The phonons of SNM exhibit coherent resonant behavior, which is believed to reduce the phonon group velocities and thus leads to a further reduction in thermal conductivity of SNMs. Our findings could be useful in the design of thermal properties of silicene for applications in thermoelectrics, thermal insulation and thermal protection. read less USED (low confidence) H. Zhang and S. W. Cranford, “In‐Plane Mechanically Gradated 2D Materials: Exploring Graphene/SiC/Silicene Transition via Full Atomistic Simulation,” Advanced Theory and Simulations. 2018. link Times cited: 3 Abstract: The emergence of 2D materials has resulted in many platforms… read moreAbstract: The emergence of 2D materials has resulted in many platforms with promising applications. One possibility is to combine two (or more) systems in a multilayered structure. However, can such materials transition in‐plane? Here, the potential of graded transition from graphene to silicene, via 2D silicon carbide is explored. The work focuses on mechanical performance of a two‐phase gradated system under uniaxial stress. The percentage of the carbon/silicon in‐plane, to explore the resulting effects on strength and stiffness using full atomistic molecular dynamics (MD) is varied. Carbon atom placement of 0% to 100% in nine increments with random substitution, is tested using both single‐bond and mixed‐bond homogeneous and two‐phase gradated models. Stiffness and strength can be predicted by a simple model accounting for proportional bond distributions. It is demonstrated that the inclusion of nominal amounts of Si–C bonding results in drastic changes in mechanical response when compared to graphene, tolerant to change across a wide range of distributions, suggesting a “weakest link” effect. For the two‐phase gradated systems, stress contour plots correlate with changes in silicon‐to‐carbon ratios. The work demonstrates the feasibility of a new class of 2D in‐plane gradated materials with tunable stiffness, predictable strength, and controlled failure. read less USED (low confidence) L. Qiu, H. Zou, N. Zhu, Y. Feng, X. Zhang, and X. Zhang, “Iodine nanoparticle-enhancing electrical and thermal transport for carbon nanotube fibers,” Applied Thermal Engineering. 2018. link Times cited: 42 USED (low confidence) A. K. Roy, S. Das, M. F. Shahriar, G. K. Biswas, and S. Das, “Relation between the thermal conductivity and grain size in a polycrystalline silicene sheet.” 2018. link Times cited: 4 Abstract: Silicene, a two-dimensional allotrope of silicon, has outsta… read moreAbstract: Silicene, a two-dimensional allotrope of silicon, has outstanding mechanical and electrical properties which have triggered extensive research on its application in the field of developing faster computer chips, more efficient solar cells, improved medical technologies, vehicle, and aircraft parts, etc. In this work, we have demonstrated a way to use large-scale molecular dynamics to explore the effective thermal conductivity of nano-grained polycrystalline 2-D Silicene sheets and compare it with a pristine one. By performing non-equilibrium molecular dynamics (NEMD) simulations, the effect of grain size on the thermal conductivity of polycrystalline Silicene sheets has been investigated. For both pristine and polycrystalline Silicene sheet, structures of 30 nm × 30 nm are considered and Stillinger-Weber potential is used to investigate the atoms’ interaction with theneighborhood. The temperature profiles are used to find the thermal conductivity by Fourier’s Law of conduction. Comparing with the pristine Silicene sheet we have found a very intriguing result. Our results reveal that the ultra-fine nano-grained Silicene structures have an increasing trend for thermal conductivity commensurate with grain size. Larger the grain size becomes, higher the thermal conductivity is. However, for very small grain size the thermal conductivity is considerably less than the pristine structure. It is also noticed that the thermal conductivity of smaller grain size structures shows more grain size dependency while the thermal conductivity for larger grain size exhibits trivial gradient and almost converges to some certain range of values.The grain size based rising trend is then evaluatedby specific heat calculation.The density of states (DOS) is ultimately calculated for different grain sizes to verify the trend of changing thermal conductivities on the basis of noise sensitivity.Silicene, a two-dimensional allotrope of silicon, has outstanding mechanical and electrical properties which have triggered extensive research on its application in the field of developing faster computer chips, more efficient solar cells, improved medical technologies, vehicle, and aircraft parts, etc. In this work, we have demonstrated a way to use large-scale molecular dynamics to explore the effective thermal conductivity of nano-grained polycrystalline 2-D Silicene sheets and compare it with a pristine one. By performing non-equilibrium molecular dynamics (NEMD) simulations, the effect of grain size on the thermal conductivity of polycrystalline Silicene sheets has been investigated. For both pristine and polycrystalline Silicene sheet, structures of 30 nm × 30 nm are considered and Stillinger-Weber potential is used to investigate the atoms’ interaction with theneighborhood. The temperature profiles are used to find the thermal conductivity by Fourier’s Law of conduction. Comparing with the pristine... read less USED (low confidence) A. Bourque and G. Rutledge, “Heterogeneous nucleation of an n-alkane on graphene-like materials,” European Polymer Journal. 2018. link Times cited: 17 USED (low confidence) Z. Lorestaniweiss and Z. Rashidian, “Pure spin polarized current through a full magnetic silicene junction,” Physica C: Superconductivity and its Applications. 2018. link Times cited: 0 USED (low confidence) B. Mortazavi, M. Shahrokhi, X. Zhuang, and T. Rabczuk, “Boron–graphdiyne: a superstretchable semiconductor with low thermal conductivity and ultrahigh capacity for Li, Na and Ca ion storage,” Journal of Materials Chemistry. 2018. link Times cited: 90 Abstract: Most recently, boron–graphdiyne, a π-conjugated two-dimensio… read moreAbstract: Most recently, boron–graphdiyne, a π-conjugated two-dimensional (2D) structure made from a merely sp carbon skeleton connected with boron atoms was successfully experimentally realized through a bottom-up synthetic strategy. Motivated by this exciting experimental advance, we conducted density functional theory (DFT) and classical molecular dynamics simulations to study the mechanical, thermal conductivity and stability, electronic and optical properties of single-layer B-graphdiyne. We particularly analyzed the application of this novel 2D material as an anode for Li, Na, Mg and Ca ion storage. Uniaxial tensile simulation results reveal that B-graphdiyne owing to its porous structure and flexibility can yield superstretchability. The single-layer B-graphdiyne was found to exhibit a semiconducting electronic character, with a narrow band-gap of 1.15 eV based on the HSE06 prediction. It was confirmed that mechanical straining can be employed to further tune the optical absorbance and electronic band-gap of B-graphdiyne. Ab initio molecular dynamics results reveal that B-graphdiyne can withstand high temperatures, like 2500 K. The thermal conductivity of suspended single-layer B-graphdiyne was predicted to be very low, ∼2.5 W mK−1 at room temperature. Our first-principles results reveal the outstanding prospect of B-graphdiyne as an anode material with ultrahigh charge capacities of 808 mA h g−1, 5174 mA hg−1 and 3557 mA h g−1 for Na, Ca and Li ion storage, respectively. The comprehensive insight provided by this investigation highlights the outstanding physics of B-graphdiyne nanomembranes, and suggests them as highly promising candidates for the design of novel stretchable nanoelectronics and energy storage devices. read less USED (low confidence) N. T. Long, H. A. Huy, T. Q. Tuan, O. K. Le, V. V. Hoang, and N. H. Giang, “Crystallization of supercooled liquid and amorphous silicene,” Journal of Non-crystalline Solids. 2018. link Times cited: 5 USED (low confidence) H. Dong, Z. Fan, L. Shi, A. Harju, and T. Ala-Nisilla, “Equivalence of the equilibrium and the nonequilibrium molecular dynamics methods for thermal conductivity calculations: From bulk to nanowire silicon,” Physical Review B. 2018. link Times cited: 43 Abstract: © 2018 American Physical Society. Molecular dynamics (MD) si… read moreAbstract: © 2018 American Physical Society. Molecular dynamics (MD) simulations play an important role in studying heat transport in complex materials. The lattice thermal conductivity can be computed either using the Green-Kubo formula in equilibrium MD (EMD) simulations or using Fourier's law in nonequilibrium MD (NEMD) simulations. These two methods have not been systematically compared for materials with different dimensions and inconsistencies between them have been occasionally reported in the literature. Here we give an in-depth comparison of them in terms of heat transport in three allotropes of Si: three-dimensional bulk silicon, two-dimensional silicene, and quasi-one-dimensional silicon nanowire. By multiplying the correlation time in the Green-Kubo formula with an appropriate effective group velocity, we can express the running thermal conductivity in the EMD method as a function of an effective length and directly compare it to the length-dependent thermal conductivity in the NEMD method. We find that the two methods quantitatively agree with each other for all the systems studied, firmly establishing their equivalence in computing thermal conductivity. read less USED (low confidence) J. Zheng, F. Chi, and Y. Guo, “Thermal Spin Generator Based on a Germanene Nanoribbon Subjected to Local Noncollinear Exchange Fields,” Physical review applied. 2018. link Times cited: 11 USED (low confidence) H. Wang, G. Qin, G. Li, Q. Wang, and M. Hu, “Unconventional thermal transport enhancement with large atom mass: a comparative study of 2D transition dichalcogenides,” 2D Materials. 2017. link Times cited: 8 Abstract: 2D layered transition dichalcogenides have attracted tremend… read moreAbstract: 2D layered transition dichalcogenides have attracted tremendous attention for their excellent properties and multifarious applications. In particular, NbSe2 and TaSe2 are the canonical systems to study superconductivity and charge density waves. Here, we perform a comparative study of the thermal transport properties of 2D NbSe2 and TaSe2 for both 1T and 2H phases based on first-principles calculations. Usually, the lattice thermal conductivity (κL) is smaller with larger average atom mass. However, it is contrary for the comparison between TaSe2 and NbSe2, despite the heavier Ta than Nb. The abnormally larger κL of TaSe2 originates from the weakened phonon–phonon scattering due to the combination of large phonon bandgap and bunching of the acoustic phonon branches, which is caused by the larger mass difference. On one hand, the large bandgap hinders the acoustic–optical phonon scattering. On the other hand, the bunching of the acoustic phonon branches hampers Umklapp process by weakening the high frequency acoustic–acoustic phonon scattering. The special characteristics of phonon transport are further conformed by mode level analysis and scattering channels of phonon–phonon scattering. Moreover, lower κL of 1T phase for both Nb and Ta selenides compared to 2H phase are also reported, which stems from the stronger anharmonicity. read less USED (low confidence) S.-Y. Xiong and G. Cao, “Continuum thin-shell model of the anisotropic two-dimensional materials: Single-layer black phosphorus,” Extreme Mechanics Letters. 2017. link Times cited: 13 USED (low confidence) G. Qin, H. Xie, M. Hu, and H. Bao, “Two-dimensional silicon.” 2017. link Times cited: 0 USED (low confidence) X. Tan, S. C. Smith, and Z. Chen, “Hexagonal honeycomb silicon: Silicene.” 2017. link Times cited: 0 USED (low confidence) G. G. Guzmán-Verri, L. L. Y. Voon, and M. Willatzen, “Fundamentals of silicene.” 2017. link Times cited: 0 USED (low confidence) M. Sledzinska et al., “Record Low Thermal Conductivity of Polycrystalline MoS2 Films: Tuning the Thermal Conductivity by Grain Orientation.,” ACS applied materials & interfaces. 2017. link Times cited: 34 Abstract: We report a record low thermal conductivity in polycrystalli… read moreAbstract: We report a record low thermal conductivity in polycrystalline MoS2 obtained for ultrathin films with varying grain sizes and orientations. By optimizing the sulfurization parameters of nanometer-thick Mo layers, five MoS2 films containing a combination of horizontally and vertically oriented grains, with respect to the bulk (001) monocrystal, were grown. From transmission electron microscopy, the average grain size, typically below 10 nm, and proportion of differently oriented grains were extracted. The thermal conductivity of the suspended samples was extracted from a Raman laser-power-dependent study, and the lowest value of thermal conductivity of 0.27 W m-1 K-1, which reaches a similar value as that of Teflon, is obtained in a polycrystalline sample formed by a combination of horizontally and vertically oriented grains in similar proportion. Analysis by means of molecular dynamics and finite element method simulations confirm that such a grain arrangement leads to lower grain boundary conductance. We discuss the possible use of these thermal insulating films in the context of electronics and thermoelectricity. read less USED (low confidence) X. Wang, Y. Hong, P. Chan, and J. Zhang, “Phonon thermal transport in silicene-germanene superlattice: a molecular dynamics study,” Nanotechnology. 2017. link Times cited: 34 Abstract: Two-dimensional (2D) hybrid materials have drawn enormous at… read moreAbstract: Two-dimensional (2D) hybrid materials have drawn enormous attention in thermoelectric applications. In this work, we apply a molecular dynamics (MD) simulation to investigate the phonon thermal transport in silicene-germanene superlattice. A non-monotonic thermal conductivity of silicene-germanene superlattice with period length is revealed, which is due to the coherent–incoherent phonon conversion and phonon confinement mechanisms. We also calculate the thermal conductivity of a Si-Ge random mixing monolayer, showing a U-shaped trend. Because of the phonon mode localizations at Ge concentration of <20% and >80%, thermal conductivity varies dramatically at low doping regions. By changing the total length (Ltotal), the infinite-length thermal conductivities of pure silicene, pure germanene, silicene-germanene superlattice, and Si-Ge random mixing monolayer are extracted as 16.08, 15.95, 5.60 and 4.47 W/m-K, respectively. The thermal boundary conductance (TBC) of the silicene-germanene is also evaluated, showing a small thermal rectification. At Ltotal = 274.7 nm, the TBC of silicene to germanene is 620.49 MW/m2-K, while that of germanene to silicene is 528.76 MW/m2-K. read less USED (low confidence) Y.-K. Feng and X.-gang Liang, “Thermal Rectification of Silicene Nanosheets With Triangular Cavities by Molecular Dynamics Simulations,” Journal of Heat Transfer-transactions of The Asme. 2017. link Times cited: 9 USED (low confidence) B. Mortazavi, “Ultra high stiffness and thermal conductivity of graphene like C3N,” Carbon. 2017. link Times cited: 217 USED (low confidence) Z. Qin, G. Qin, X. Zuo, Z. Xiong, and M. Hu, “Orbitally driven low thermal conductivity of monolayer gallium nitride (GaN) with planar honeycomb structure: a comparative study.,” Nanoscale. 2017. link Times cited: 116 Abstract: Two-dimensional (2D) materials with graphene as a representa… read moreAbstract: Two-dimensional (2D) materials with graphene as a representative have been intensively studied for a long time. Recently, monolayer gallium nitride (ML GaN) with honeycomb structure was successfully fabricated in experiments, generating enormous research interest for its promising applications in nano- and opto-electronics. Considering all these applications are inevitably involved with thermal transport, systematic investigation of the phonon transport properties of 2D GaN is in demand. In this paper, by solving the Boltzmann transport equation (BTE) based on first-principles calculations, we performed a comprehensive study of the phonon transport properties of ML GaN, with detailed comparison to bulk GaN, 2D graphene, silicene and ML BN with similar honeycomb structure. Considering the similar planar structure of ML GaN to graphene, it is quite intriguing to find that the thermal conductivity (κ) of ML GaN (14.93 W mK-1) is more than two orders of magnitude lower than that of graphene and is even lower than that of silicene with a buckled structure. Systematic analysis is performed based on the study of the contribution from phonon branches, comparison among the mode level phonon group velocity and lifetime, the detailed process and channels of phonon-phonon scattering, and phonon anharmonicity with potential energy well. We found that, different from graphene and ML BN, the phonon-phonon scattering selection rule in 2D GaN is slightly broken by the lowered symmetry due to the large difference in the atomic radius and mass between Ga and N atoms. Further deep insight is gained from the electronic structure. Resulting from the special sp orbital hybridization mediated by the Ga-d orbital in ML GaN, the strongly polarized Ga-N bond, localized charge density, and its inhomogeneous distribution induce large phonon anharmonicity and lead to the intrinsic low κ of ML GaN. The orbitally driven low κ of ML GaN unraveled in this work would make 2D GaN prospective for applications in energy conversion such as thermoelectrics. Our study offers fundamental understanding of phonon transport in ML GaN within the framework of BTE and further electronic structure, which will enrich the studies of nanoscale phonon transport in 2D materials and shed light on further studies. read less USED (low confidence) T. Min, T. Yoon, and T. Lim, “Molecular dynamics simulation of melting of silicene,” Materials Research Express. 2017. link Times cited: 8 Abstract: We report the melting temperature of free-standing silicene … read moreAbstract: We report the melting temperature of free-standing silicene by carrying out molecular dynamics (MD) simulation experiments using optimized Stillinger-Weber (SW) potential by Zhang et al (2014 Phys. Rev. B 89 054310). The melting scenario of a free-standing silicene is well captured visually in our MD simulations. The data are systematically analyzed using a few qualitatively different indicators, including caloric curve, radial distribution function and a numerical indicator known as global similarity index. The optimized SW potential consistently yields a melting temperature of 1500 K for the simulated free-standing, infinite silicene. read less USED (low confidence) G. Liu, H. Wang, Y. Gao, J. Zhou, and H. Wang, “Anisotropic intrinsic lattice thermal conductivity of borophane from first-principles calculations.,” Physical chemistry chemical physics : PCCP. 2017. link Times cited: 35 Abstract: Borophene (boron sheet) as a new type of two-dimensional (2D… read moreAbstract: Borophene (boron sheet) as a new type of two-dimensional (2D) material was grown successfully recently. Unfortunately, the structural stability of freestanding borophene is still an open issue. Theoretical research has found that full hydrogenation can remove such instability, and the product is called borophane. In this paper, using first-principles calculations we investigate the lattice dynamics and thermal transport properties of borophane. The intrinsic lattice thermal conductivity and the relaxation time of borophane are investigated by solving the phonon Boltzmann transport equation (BTE) based on first-principles calculations. We find that the intrinsic lattice thermal conductivity of borophane is anisotropic, as the higher value (along the zigzag direction) is about two times of the lower one (along the armchair direction). The contributions of phonon branches to the lattice thermal conductivities along different directions are evaluated. It is found that both the anisotropy of thermal conductivity and the different phonon branches which dominate the thermal transport along different directions are decided by the group velocity and the relaxation time of phonons with very low frequency. In addition, the size dependence of thermal conductivity is investigated using cumulative thermal conductivity. The underlying physical mechanisms of these unique properties are also discussed in this paper. read less USED (low confidence) Z. Liu, X. Wu, and T. Luo, “The impact of hydrogenation on the thermal transport of silicene,” 2D Materials. 2017. link Times cited: 21 Abstract: Silicene, the silicon counterpart of graphene, has been iden… read moreAbstract: Silicene, the silicon counterpart of graphene, has been identified as a promising 2D material for electronics applications. The reported very low thermal conductivity of silicene can potentially pose challenges on the thermal management of such nanoelectronics, which can in turn influence the device performance and reliability. Although the thermal conductivity of silicene has been studied, the impact of hydrogenation of silicene, which can happen spontaneously due to the resultant lower energy state, on its thermal transport ability is not clear. In this paper, we use first-principles calculations and iterative solution of phonon Boltzmann transport equation (BTE) to investigate and compare the thermal transport property of silicene and hydrogenated silicene. Surprisingly, we predict that the hydrogenation can lead to a large increase in thermal conductivity (from 22.5 W m−1 K−1 for silicene to 78.0 W m−1 K−1 for hydrogenated silicene at 300 K). We also find that the main contributor for such an improvement is the transverse acoustic phonon modes, and the reasons are the reduced anharmonicity as well as the reduced three-phonon scattering phase space after hydrogenation. This research may help better understand thermal transport in functionalized 2D materials and inspire new strategies to manipulate their thermal properties, which is of critical importance for designing high performance and reliable nanoelectronic devices. read less USED (low confidence) L. Zhao, S. Xu, M. Wang, and S. Lin, “Probing the Thermodynamic Stability and Phonon Transport in Two-Dimensional Hexagonal Aluminum Nitride Monolayer,” Journal of Physical Chemistry C. 2016. link Times cited: 20 Abstract: Discovery of graphene and its astonishing properties have dr… read moreAbstract: Discovery of graphene and its astonishing properties have drawn great interest in new two-dimensional (2D) materials for practical applications in micro- and nanodevices. 2D hexagonal aluminum nitride monolayer (h-AlN), a III–V group wide-bandgap semiconductor, has promising applications in optoelectronics and energy conversion. Unfortunately, their high temperature thermodynamic stability and thermal transport properties have not been reported. Here we investigate these properties, for the first time, of monolayer h-AlN using both equilibrium and nonequilibrium molecular dynamics simulations. We find that h-AlN has a very high melting point in the range of 3500–4000 K due to the strong Al–N covalent bonding. On the basis of the kinetic theory of thermal transport and quantum corrections, the intrinsic in-plane thermal conductivity of ∼264.1 W m–1 K–1 and phonon mean free path of ∼154 nm of h-AlN are estimated at quantum-corrected room temperature. The analysis of phonon transport properties demonstrates ... read less USED (low confidence) Y. Hong, J. Zhang, and X. Zeng, “Thermal Conductivity of Monolayer MoSe2 and MoS2,” Journal of Physical Chemistry C. 2016. link Times cited: 88 Abstract: Two-dimensional (2D) MoSe2 and MoS2 monolayers, two prototyp… read moreAbstract: Two-dimensional (2D) MoSe2 and MoS2 monolayers, two prototype transition metal dichalcogenides (TMDCs) materials, have attracted growing interest as promising 2D semiconductors. In this work, thermal conductivity (κ) of the monolayer MoSe2 is computed using large-scale classical nonequilibrium molecular dynamics (NEMD) simulations for the first time. The predicted κ of monolayer MoSe2 with infinite length (or MoSe2 2D sheets) are 43.88 ± 1.33 and 41.63 ± 0.66 W/(m·K) in armchair and zigzag directions, respectively. These simulation results are further confirmed by independent simulations using the Green–Kubo method (GKM), which yield computed κ of 44.38 ± 2.08 and 44.63 ± 2.50 W/(m·K), respectively. For 2D MoS2 sheet, the computed κ based on the NEMD method are 101.43 ± 1.13 and 110.30 ± 2.07 W/(m·K), respectively, in armchair and zigzag directions, whereas those based on the GKM are 102.32 ± 6.05 and 108.74 ± 6.68 W/(m·K), respectively. The predicted κ values of MoS2 monolayer are 2 times larger than tho... read less USED (low confidence) J. Zhao et al., “Rise of silicene: A competitive 2D material,” Progress in Materials Science. 2016. link Times cited: 645 USED (low confidence) N. Liu, J. Hong, R. Pidaparti, and X. Wang, “Abnormality in fracture strength of polycrystalline silicene,” 2D Materials. 2016. link Times cited: 21 Abstract: Silicene, a silicon-based homologue of graphene, arouses gre… read moreAbstract: Silicene, a silicon-based homologue of graphene, arouses great interest in nano-electronic devices due to its outstanding electronic properties. However, its promising electronic applications are greatly hindered by lack of understanding in the mechanical strength of silicene. Therefore, in order to design mechanically reliable devices with silicene, it is necessary to thoroughly explore the mechanical properties of silicene. Due to current fabrication methods, graphene is commonly produced in a polycrystalline form; the same may hold for silicene. Here we perform molecular dynamics simulations to investigate the mechanical properties of polycrystalline silicene. First, an annealing process is employed to construct a more realistic modeling structure of polycrystalline silicene. Results indicate that a more stable structure is formed due to the breaking and reformation of bonds between atoms on the grain boundaries. Moreover, as the grain size decreases, the efficiency of the annealing process, which is quantified by the energy change, increases. Subsequently, biaxial tensile tests are performed on the annealed samples in order to explore the relation between grain size and mechanical properties, namely in-plane stiffness, fracture strength and fracture strain etc. Results indicate that as the grain size decreases, the fracture strain increases while the fracture strength shows an inverse trend. The decreasing fracture strength may be partly attributed to the weakening effect from the increasing area density of defects which acts as the reservoir of stress-concentrated sites on the grain boundary. The observed crack localization and propagation and fracture strength are well-explained by a defect-pileup model. read less USED (low confidence) Y. Han, J. Dong, G. Qin, and M. Hu, “Phonon transport in the ground state of two-dimensional silicon and germanium,” RSC Advances. 2016. link Times cited: 14 Abstract: Large honeycomb dumbbell (LHD) silicene/germanene was recent… read moreAbstract: Large honeycomb dumbbell (LHD) silicene/germanene was recently found to be the ground state of two-dimensional (2D) silicon and germanium, which was much more stable than the well-known low buckled (LB) silicene/germanene (Matusalem et al., Phys. Rev. B, 92, 045436 (2015)). The existence of an intrinsic band gap of LHD silicene/germanene makes them prospective in future thermoelectric devices. In this work, lattice thermal conductivity (κ) of the LHD silicene/germanene is investigated systematically by solving the phonon Boltzmann transport equation with interatomic force constants extracted from first-principles calculations, and compared with that of low buckled (LB) silicene/germanene. It is intriguing to find that, as compared with LB silicene, although the much flatter structure of the LHD silicene/germanene leads to a significantly larger portion of the flexural modes to the overall thermal transport, the κ of the LHD silicene/germanene is only 5.9/1.6 W m−1 K−1, which is substantially lower than that of the LB silicene/germanene. We found that the volumetric specific heat, group velocity square and the phonon lifetime of the LB silicene are all larger than that of the LHD silicene/germanene, with group velocity playing the dominant role, which is further linked with the higher Young's modulus of LB silicene. Besides, the difference in phonon lifetime is further explained in terms of the potential energy change. The trend of the root mean-square displacement values and the phonon anharmonicity is opposite to that of the normalized mean lifetime, which is physically justified, as larger displacements will lead to stronger anharmonicity and reduced lifetimes. The intrinsic ultralow κ of the LHD silicene/germanene makes it prospective for thermoelectrics in the future. read less USED (low confidence) H. Liu, G. Qin, Y. Lin, and M. Hu, “Disparate Strain Dependent Thermal Conductivity of Two-dimensional Penta-Structures.,” Nano letters. 2016. link Times cited: 158 Abstract: Two-dimensional (2D) carbon allotrope called penta-graphene … read moreAbstract: Two-dimensional (2D) carbon allotrope called penta-graphene was recently proposed from first-principles calculations and various similar penta-structures emerged. Despite significant effort having been dedicated to electronic structures and mechanical properties, little research has been focused on thermal transport in penta-structures. Motivated by this, we performed a comparative study of thermal transport properties of three representative pentagonal structures, namely penta-graphene, penta-SiC2, and penta-SiN2, by solving the phonon Boltzmann transport equation with interatomic force constants extracted from first-principles calculations. Unexpectedly, the thermal conductivity of the three penta-structures exhibits diverse strain dependence, despite their very similar geometry structures. While the thermal conductivity of penta-graphene exhibits standard monotonic reduction by stretching, penta-SiC2 possesses an unusual nonmonotonic up-and-down behavior. More interestingly, the thermal conductivity of penta-SiN2 has 1 order of magnitude enhancement due to the strain induced buckled to planar structure transition. The mechanism governing the diverse strain dependence is identified as the competition between the change of phonon group velocity and phonon lifetime of acoustic phonon modes with combined effect from the unique structure transition for penta-SiN2. The disparate thermal transport behavior is further correlated to the fundamentally different bonding nature in the atomic structures with solid evidence from the distribution of deformation charge density and more in-depth molecular orbital analysis. The reported giant and robust tunability of thermal conductivity may inspire intensive research on other derivatives of penta-structures as potential materials for emerging nanoelectronic devices. The fundamental physics understood from this study also solidifies the strategy to engineer thermal transport properties of broad 2D materials by simple mechanical strain. read less USED (low confidence) K. Yuan, M. Sun, Z.-liang Wang, and D. Tang, “Tunable thermal rectification in silicon-functionalized graphene nanoribbons by molecular dynamics simulation,” International Journal of Thermal Sciences. 2015. link Times cited: 25 USED (low confidence) Y. Kuang, L. Lindsay, S. Shi, and G. Zheng, “Tensile strains give rise to strong size effects for thermal conductivities of silicene, germanene and stanene.,” Nanoscale. 2015. link Times cited: 117 Abstract: Based on first principles calculations and self-consistent s… read moreAbstract: Based on first principles calculations and self-consistent solution of the linearized Boltzmann-Peierls equation for phonon transport approach within a three-phonon scattering framework, we characterize lattice thermal conductivities k of freestanding silicene, germanene and stanene under different isotropic tensile strains and temperatures. We find a strong size dependence of k for silicene with tensile strain, i.e., divergent k with increasing system size; however, the intrinsic room temperature k for unstrained silicene converges with system size to 19.34 W m(-1) K(-1) at 178 nm. The room temperature k of strained silicene becomes as large as that of bulk silicon at 84 μm, indicating the possibility of using strain in silicene to manipulate k for thermal management. The relative contribution to the intrinsic k from out-of-plane acoustic modes is largest for unstrained silicene, ∼39% at room temperature. The single mode relaxation time approximation, which works reasonably well for bulk silicon, fails to appropriately describe phonon thermal transport in silicene, germanene and stanene within the temperature range considered. For large samples of silicene, k increases with tensile strain, peaks at ∼7% strain and then decreases with further strain. In germanene and stanene, increasing strain hardens and stabilizes long wavelength out-of-plane acoustic phonons, and leads to similar k behaviors to those of silicene. These findings further our understanding of phonon dynamics in group-IV buckled monolayers and may guide transfer and fabrication techniques for these freestanding samples and engineering of k by size and strain for applications of thermal management and thermoelectricity. read less USED (low confidence) A. Tabarraei, “Thermal conductivity of monolayer hexagonal boron nitride nanoribbons,” Computational Materials Science. 2015. link Times cited: 71 USED (low confidence) J. Zhang, Y. Hong, Z. Tong, Z. Xiao, H. Bao, and Y. Yue, “Molecular dynamics study of interfacial thermal transport between silicene and substrates.,” Physical chemistry chemical physics : PCCP. 2015. link Times cited: 41 Abstract: In this work, the interfacial thermal transport across silic… read moreAbstract: In this work, the interfacial thermal transport across silicene and various substrates, i.e., crystalline silicon (c-Si), amorphous silicon (a-Si), crystalline silica (c-SiO2) and amorphous silica (a-SiO2) are explored by classical molecular dynamics (MD) simulations. A transient pulsed heating technique is applied in this work to characterize the interfacial thermal resistance in all hybrid systems. It is reported that the interfacial thermal resistances between silicene and all substrates decrease nearly 40% with temperature from 100 K to 400 K, which is due to the enhanced phonon couplings from the anharmonicity effect. Analysis of phonon power spectra of all systems is performed to interpret simulation results. Contradictory to the traditional thought that amorphous structures tend to have poor thermal transport capabilities due to the disordered atomic configurations, it is calculated that amorphous silicon and silica substrates facilitate the interfacial thermal transport compared with their crystalline structures. Besides, the coupling effect from substrates can improve the interface thermal transport up to 43.5% for coupling strengths χ from 1.0 to 2.0. Our results provide fundamental knowledge and rational guidelines for the design and development of the next-generation silicene-based nanoelectronics and thermal interface materials. read less USED (low confidence) M. A. Balatero, G. J. Paylaga, N. T. Paylaga, and R. Bantaculo, “Molecular Dynamics Simulations of Thermal Conductivity of Germanene Nanoribbons (GeNR) with Armchair and Zigzag Chirality,” Applied Mechanics and Materials. 2015. link Times cited: 9 Abstract: Germanene, an allotrope of germanium which is a two dimensio… read moreAbstract: Germanene, an allotrope of germanium which is a two dimensional material with sp2 hybridization, has almost the same properties with graphene except for its buckled structure. In this study, germanium nanoribbon (GeNR) is use for it is still a new material for nanoscale level of research. In this paper, we investigate the effect of chirality on the thermal conductivity of zigzag GeNR (ZGeNR) and armchair GeNR (AGeNR) chiralities using equilibrium molecular dynamics with varied lengths at fixed temperature and varied temperatures at fixed length. The simulations were carried out in Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) using Tersoff potential for the Ge-Ge interactions. The thermal conductivity is calculated using Green-Kubo method. It is found that the chirality can affect the thermal conductivity of GeNR. Our results show that thermal conductivity of AGeNR is higher than ZGeNR in both increasing temperatures and lengths similar to the thermal conductivity behavior obtained in silicene nanoribbons [Int. J. Mech. Mater. Des. 9 (2013) 105]. read less USED (low confidence) Y. Jing, M. Hu, Y. Gao, L. Guo, and Y. Sun, “On the origin of abnormal phonon transport of graphyne,” International Journal of Heat and Mass Transfer. 2015. link Times cited: 23 USED (low confidence) H. Fu, D. Wu, Z.-Q. Zhang, and L. Gu, “Spin-dependent Seebeck Effect, Thermal Colossal Magnetoresistance and Negative Differential Thermoelectric Resistance in Zigzag Silicene Nanoribbon Heterojunciton,” Scientific Reports. 2015. link Times cited: 40 USED (low confidence) J. M. P. Tagalog, C. G. G. Alipala, G. J. Paylaga, N. T. Paylaga, and R. Bantaculo, “Molecular Dynamics Simulation of the Thermal Conductivity of Silicon-Germanene Nanoribbon (SiGeNR): A Comparison with Silicene Nanoribbon (SiNR) and Germanene Nanoribbon (GeNR),” Advanced Materials Research. 2015. link Times cited: 4 Abstract: This study examines the nature of thermal transport properti… read moreAbstract: This study examines the nature of thermal transport properties of single layer two-dimensional honeycomb structures of silicon-germanene nanoribbon (SiGeNR), silicene nanoribbon (SiNR) and germanene nanoribbon (GeNR) which have not yet been characterized experimentally. SiGeNR, SiNR and GeNR are the allotropes of silicon-germanium, silicon and germanium, respectively, with sp2 hybridization. The thermal conductivity of the materials has been investigated using Tersoff potential through LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) by performing the molecular-dynamics simulations. The temperature is varied (50 K, 77 K, 150 K, 300 K, 500 K, 700 K, 1000 K, and 1200 K) with fixed nanoribbon dimension of 50 nm × 10 nm. The length is also varied (10 nm, 20 nm, 30 nm, 40 nm, and 50 nm) while the temperature is fixed at room temperature and the width is also fixed at 10 nm. The obtained results showed that the thermal conductivity of SiGeNR at room temperature is approximately 10 times higher than GeNR and approximately 6 times higher compared to SiNR. The thermal conductivity increases as the temperature is increased from 50 K – 300 K, and as the temperature is further increased, the thermal conductivity decreases with temperature. Moreover, the thermal conductivity in SiGeNR, SiNR, and GeNR increases as the length is being increased. Predicting new features of SiGeNR, SiNR and GeNR open new possibilities for nanoelectronic device applications of group IV two-dimensional materials. read less USED (low confidence) E. D. Monterola, N. T. Paylaga, G. J. Paylaga, and R. Bantaculo, “Anomalous Effect on the Phononic Thermal Conductivity of Silicene Nanoribbon by Hydrogenation,” Advanced Materials Research. 2015. link Times cited: 3 Abstract: Silicene is a two-dimensional (2D) allotrope of silicon know… read moreAbstract: Silicene is a two-dimensional (2D) allotrope of silicon known to have a lower thermal conductivity than graphene; thus, more suitable for thermoelectric applications. This paper investigates the effect of hydrogenation on the thermal conductivity of silicene nanoribbon (SiNR) using equilibrium molecular dynamics (EMD) simulations. The simulations were carried out in Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) using a modified Tersoff potential that considers both Si-Si and Si-H interactions. The thermal conductivity of fully hydrogenated silicene nanoribbon (H-SiNR), also known as silicane nanoribbon, was found to be higher than that of pristine SiNR in all the temperatures and dimensions considered here. This anomalous enhancement in the thermal conductivity is similar to that found in hydrogenated silicon nanowires (H-SiNWs). A mechanism for this anomalous effect has been proposed relating the hydrogenation of SiNR with the stiffening and increase of the acoustic out-of-plane flexural (ZA) phonon modes. Also, for both SiNR and H-SiNR, the thermal conductivities generally increase as the dimensions are increased while they generally decrease as the temperatures are increased, in agreement to other reports. read less USED (low confidence) C. G. G. Alipala, G. J. Paylaga, N. T. Paylaga, and R. Bantaculo, “Thermal Conductivity of Silicon-Graphene Nanoribbon (SiGNR): An Equilibrium Molecular Dynamics (EMD) Simulation,” Advanced Materials Research. 2015. link Times cited: 2 Abstract: Silicon-graphene nanoribbon (SiGNR), an allotrope of silicon… read moreAbstract: Silicon-graphene nanoribbon (SiGNR), an allotrope of silicon carbide with sp2 hybridization, gains interest nowadays in the world of two-dimensional materials. In this study, the thermal conductivity of SiGNR is investigated and compared to that of graphene nanoribbon (GNR) and silicene nanoribbon (SiNR). Molecular Dynamics using Tersoff potential through Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) using the Green-Kubo method is employed to predict the thermal conductivity of silicon-graphene materials with armchair chirality. The temperature is varied from 50 K, 77 K, 150 K, 300 K, 500 K, 700 K, 1000 K, 1200 K, and 1500 K with a fixed width of 10 nm and length of 50 nm. The length of the materials is also varied from 10 nm, 20 nm, 30 nm, 40 nm and 50 nm with a fixed temperature of 300 K. Our results show that the thermal conductivity of SiGNR is higher than that of GNR and is approximately 50% larger at room temperature, which may be attributed to the presence of Si atoms inducing larger flexural phonon density of states than in GNR and SiNR. Also, the thermal conductivity of SiGNR follows the same length-dependent behavior of GNR due to its long mean free path. This study presents new insights into the thermal properties of silicon-graphene which will be significant for nanoelectronic applications. read less USED (low confidence) B. Liu et al., “INTERFACE THERMAL CONDUCTANCE AND RECTIFICATION IN HYBRID GRAPHENE/SILICENE MONOLAYER,” Carbon. 2014. link Times cited: 110 USED (low confidence) B. Liu et al., “Interfacial thermal conductance of a silicene/graphene bilayer heterostructure and the effect of hydrogenation.,” ACS applied materials & interfaces. 2014. link Times cited: 113 Abstract: van der Waals heterostructures, obtained by stacking layers … read moreAbstract: van der Waals heterostructures, obtained by stacking layers of isolated two-dimensional atomic crystals like graphene (GE) and silicene (SE), are one of emerging nanomaterials for the development of future multifunctional devices. Thermal transport behaviors at the interface of these heterostructures play a pivotal role in determining their thermal properties and functional performance. Using molecular dynamics simulations, the interfacial thermal conductance G of an SE/GE bilayer heterostructure is studied. Simulations show that G of a pristine SE/GE bilayer at room temperature is 11.74 MW/m(2)K when heat transfers from GE to SE, and is 9.52 MW/m(2)K for a reverse heat transfer, showing apparent thermal rectification effects. In addition, G increases monotonically with both the temperature and the interface coupling strength. Furthermore, hydrogenation of GE is efficient in enhancing G if an optimum hydrogenation pattern is adopted. By changing the hydrogen coverage f, G can be controllably manipulated and maximized up to five times larger than that of pristine SE/GE. This study is helpful for understanding the interface thermal transport behaviors of novel van der Waals heterostructures and provides guidance for the design and control of their thermal properties. read less USED (low confidence) G. Qin, Q.-B. Yan, Z. Qin, S. Yue, M. Hu, and G. Su, “Anisotropic intrinsic lattice thermal conductivity of phosphorene from first principles.,” Physical chemistry chemical physics : PCCP. 2014. link Times cited: 309 Abstract: Phosphorene, the single layer counterpart of black phosphoru… read moreAbstract: Phosphorene, the single layer counterpart of black phosphorus, is a novel two-dimensional semiconductor with high carrier mobility and a large fundamental direct band gap, which has attracted tremendous interest recently. Its potential applications in nano-electronics and thermoelectrics call for fundamental study of the phonon transport. Here, we calculate the intrinsic lattice thermal conductivity of phosphorene by solving the phonon Boltzmann transport equation (BTE) based on first-principles calculations. The thermal conductivity of phosphorene at 300 K is 30.15 W m(-1) K(-1) (zigzag) and 13.65 W m(-1) K(-1) (armchair), showing an obvious anisotropy along different directions. The calculated thermal conductivity fits perfectly to the inverse relationship with temperature when the temperature is higher than Debye temperature (ΘD = 278.66 K). In comparison to graphene, the minor contribution around 5% of the ZA mode is responsible for the low thermal conductivity of phosphorene. In addition, the representative mean free path (MFP), a critical size for phonon transport, is also obtained. read less USED (low confidence) H. Xie, M. Hu, and H. Bao, “Thermal conductivity of silicene from first-principles,” Applied Physics Letters. 2014. link Times cited: 148 Abstract: Silicene, as a graphene-like two-dimensional material, now r… read moreAbstract: Silicene, as a graphene-like two-dimensional material, now receives exceptional attention of a wide community of scientists and engineers beyond graphene. Despite extensive study on its electric property, little research has been done to accurately calculate the phonon transport of silicene so far. In this paper, thermal conductivity of monolayer silicene is predicted from first-principles method. At 300 K, the thermal conductivity of monolayer silicene is found to be 9.4 W/mK and much smaller than bulk silicon. The contributions from in-plane and out-of-plane vibrations to thermal conductivity are quantified, and the out-of-plane vibration contributes less than 10% of the overall thermal conductivity, which is different from the results of the similar studies on graphene. The difference is explained by the presence of small buckling, which breaks the reflectional symmetry of the structure. The flexural modes are thus not purely out-of-plane vibration and have strong scattering with other modes. read less USED (low confidence) W. Li, W. Zhang, X. Huang, X. Mu, and Y. Ni, “Regulating phonon transport in silicon nanofilms by resonant nanopillars,” International Journal of Heat and Mass Transfer. 2024. link Times cited: 0 USED (low confidence) K. Zhou and B. Liu, “Application of molecular dynamics simulation in thermal problems,” Molecular Dynamics Simulation. 2022. link Times cited: 1 USED (low confidence) F. Yang, “Thermal transport properties of two-dimensional materials.” 2020. link Times cited: 0 USED (low confidence) H. Li and R. Q. Zhang, “Phonon Thermal Transport in Silicene and Its Defect Effects.” 2018. link Times cited: 0 USED (low confidence) L. L. Y. Voon, “Physical Properties of Silicene.” 2016. link Times cited: 11 USED (low confidence) U. Ray, “Investigating thermal transport in isotope substituted nanomaterials using molecular simulations.” 2015. link Times cited: 0 Abstract: ......... 23 References........ 35 CHAPTER 4. DISSIMILAR HEA… read moreAbstract: ......... 23 References........ 35 CHAPTER 4. DISSIMILAR HEAT CONDUCTION MECHANISMS IN ANALOGOUS 2D NANOMATERIALS WITH ISOTOPE SUBSTITUTION: GRAPHENE VERSUS SILICENE 37 Abstract 37 Results and Discussion 39 37 Results and Discussion 39 read less NOT USED (low confidence) S. Ghosal, A. Bandyopadhyay, S. Chowdhury, and D. Jana, “A review on transport characteristics and bio-sensing applications of silicene,” Reports on Progress in Physics. 2023. link Times cited: 2 Abstract: Silicene, a silicon counterpart of graphene, has been predic… read moreAbstract: Silicene, a silicon counterpart of graphene, has been predicted to possess Dirac fermions. The effective spin–orbit interaction in silicene is quite significant compared to graphene; as a result, buckled silicene exhibits a finite band gap of a few meV at the Dirac point. This band gap can be further tailored by applying in plane strain, an external electric field, chemical functionalization and defects. This special feature allows silicene and its various derivatives as potential candidates for device applications. In this topical review, we would like to explore the transport features of the pristine silicene and its possible nano derivatives. As a part of it, Thermoelectric properties as well as several routes for thermoelectric enhancement in silicene are investigated. Besides, the recent progress in biosensing applications of silicene and its hetero-structures will be highlighted. We hope the results obtained from recent experimental and theoretical studies in silicene will setup a benchmark in diverse applications such as in spintronics, bio-sensing and opto-electronic devices. read less NOT USED (low confidence) J. Deb, R. Majidi, and U. Sarkar, “Bilayer CdS Structure: A Promising Candidate for Photocatalytic and Optoelectronic Applications,” ACS Applied Optical Materials. 2022. link Times cited: 6 NOT USED (low confidence) J. Cai, E. Estakhrianhaghighi, and A. Akbarzadeh, “Functionalized Graphene Origami Metamaterials with Tunable Thermal Conductivity,” MatSciRN EM Feeds. 2022. link Times cited: 11 Abstract: Graphene with tunable thermo-mechanical property is of great… read moreAbstract: Graphene with tunable thermo-mechanical property is of great importance for next-generation thermal management devices. Distinct from previously reported porous graphene materials that tune the thermal conductivity at the cost of degrading their mechanical properties, non-porous hydrogenated graphene origami metamaterial exhibits a unique combination of tunable thermal conductivity, high strength, and enhanced stretchability. Through molecular dynamics simulation, an extremely broad range of thermal conductivity can be obtained by tuning the geometrical parameters of the Miura-ori nanoarchitecture of graphene origami, altering the adatom types and density, designing new origami patterns, and applying mechanical strains. By analyzing and comparing the results from atomistic and continuum-based simulations, the effect of length scale on the thermal property of graphene origami metamaterials is explored. The temperature distribution and the phonon density of states of the proposed graphene origami are examined to illustrate the heat conduction mechanism. Finally, 3D graphene origami metamaterials are constructed based on the coupling and assembling of graphene origami strips, and their thermo-mechanical performance is elucidated. Negative coefficients of thermal expansion are obtained in graphene origami nanotubes. The introduced strategy for controlling the thermo-mechanical properties of graphene metamaterials can open up new avenues for developing thermoelectric devices, heat management systems, and flexible nanoelectronics. read less NOT USED (low confidence) K. Dheeraj and S. P. Sathian, “The disparate effect of strain on thermal conductivity of 2-D materials.,” Physical chemistry chemical physics : PCCP. 2021. link Times cited: 1 Abstract: Thermal transport in 2-D (dimensional) structures is highly … read moreAbstract: Thermal transport in 2-D (dimensional) structures is highly susceptible to external perturbations such as strain, owing to their high surface-to-volume ratio. In this study, we investigate the influence of strain on the thermal conductivity of flat (graphene and hexagonal boron nitride), buckled and puckered (molybdenum disulfide and black phosphorous) 2-D materials. Unlike bulk materials where the thermal conductivity reduces with strain, the thermal conductivity of 2-D materials under strain is observed to be unique and dependent on the material considered. To understand such diverse strain-dependent thermal conductivity in 2-D materials, the phonon mode properties are calculated. It was observed that the strain softens the longitudinal mode (LA), whereas the out-of-plane acoustic mode (ZA) undergoes stiffening albeit various extents. In flat 2-D materials, the dispersion of ZA mode is linearized under strain while it tends to linearize in buckled and puckered structures. The variation in the phonon group velocity of ZA mode coupled with the anomalous behavior of the phonon lifetime of acoustic modes results in a diverse strain dependence of the thermal conductivity of 2-D materials. Our findings offer insight into the influence of strain of 2-D materials and will be helpful in tailoring the thermal properties of these materials for various applications such as nanoelectronics and thermoelectric devices. read less NOT USED (low confidence) H. A. Eivari, Z. sohbatzadeh, P. Mele, and M. H. N. Assadi, “Low Thermal Conductivity: Fundamentals and Theoretical Aspects in Thermoelectric Applications,” Materials Today Energy. 2021. link Times cited: 39 NOT USED (low confidence) B. Mortazavi, E. Podryabinkin, S. Roche, T. Rabczuk, X. Zhuang, and A. Shapeev, “Machine-learning interatomic potentials enable first-principles multiscale modeling of lattice thermal conductivity in graphene/borophene heterostructures,” Materials Horizons. 2020. link Times cited: 81 Abstract: We highlight that machine-learning interatomic potentials tr… read moreAbstract: We highlight that machine-learning interatomic potentials trained over short AIMD trajectories enable first-principles multiscale modeling, bridging DFT level accuracy to the continuum level and empowering the study of complex/novel nanostructures. read less NOT USED (low confidence) B. Mortazavi et al., “Efficient machine-learning based interatomic potentialsfor exploring thermal conductivity in two-dimensional materials,” Journal of Physics: Materials. 2020. link Times cited: 39 Abstract: It is well-known that the calculation of thermal conductivit… read moreAbstract: It is well-known that the calculation of thermal conductivity using classical molecular dynamics (MD) simulations strongly depends on the choice of the appropriate interatomic potentials. As proven for the case of graphene, while most of the available interatomic potentials estimate the structural and elastic constants with high accuracy, when employed to predict the lattice thermal conductivity they however lead to a variation of predictions by one order of magnitude. Here we present our results on using machine-learning interatomic potentials (MLIPs) passively fitted to computationally inexpensive ab-initio molecular dynamics trajectories without any tuning or optimizing of hyperparameters. These first-attempt potentials could reproduce the phononic properties of different two-dimensional (2D) materials obtained using density functional theory (DFT) simulations. To illustrate the efficiency of the trained MLIPs, we consider polyaniline C3N nanosheets. C3N monolayer was selected because the classical MD and different first-principles results contradict each other, resulting in a scientific dilemma. It is shown that the predicted thermal conductivity of 418 ± 20 W mK−1 for C3N monolayer by the non-equilibrium MD simulations on the basis of a first-attempt MLIP evidences an improved accuracy when compared with the commonly employed MD models. Moreover, MLIP-based prediction can be considered as a solution to the debated reports in the literature. This study highlights that passively fitted MLIPs can be effectively employed as versatile and efficient tools to obtain accurate estimations of thermal conductivities of complex materials using classical MD simulations. In response to remarkable growth of 2D materials family, the devised modeling methodology could play a fundamental role to predict the thermal conductivity. read less NOT USED (low confidence) K. Lee, D. Yoo, W. Jeong, and S. Han, “SIMPLE-NN: An efficient package for training and executing neural-network interatomic potentials,” Comput. Phys. Commun. 2019. link Times cited: 75 NOT USED (low confidence) Y. Gao, X. Zhang, D. Tang, and M. Hu, “Unexpected anisotropy of (14,14,14)-Graphyne: A comprehensive study on the thermal transport properties of graphyne based nanomaterials,” Carbon. 2019. link Times cited: 18 NOT USED (low confidence) B. Liu and K. Zhou, “Recent progress on graphene-analogous 2D nanomaterials: Properties, modeling and applications,” Progress in Materials Science. 2019. link Times cited: 208 NOT USED (low confidence) N. Singh and M. Sahoo, “Investigation of Silicene Nanoribbon Tunnel FET for Low Power Digital VLSI Circuit Application with Variation of Device Parameters,” 2018 10th International Conference on Communications, Circuits and Systems (ICCCAS). 2018. link Times cited: 1 Abstract: The unique properties of single layer materials different fr… read moreAbstract: The unique properties of single layer materials different from their bulk form make them suitable for nanoscale applications. This work presents study of p-i-n based Silicene Nanoribbon (SiNR) Tunnel Field Effect Transistor using NEGF formalism. The Device characteristics, ION/IOFF ratio have been studied by varying high-k dielectric, source and drain doping in SiNR TFET. The obtained ION/IOFF ratios for different gate dielectrics materials are compared with the reported data in literatures and it is observed that the ON current can be increased by using high-k dielectric but for the materials whose dielectric constant exceeds HfO2, OFF current will also increase. So, it can be inferred that deploying gate material of very high dielectric constant will not be of much benefit rather it will reduce ION/IOFF ratio, which is one of the key FOM in Digital VLSI circuits. HfO2 can be potential high-k material to be used as gate oxides because of its highest ION/IOFF ratio among all dielectric materials used for constant drain and source doping. OFF current is not much influenced by source doping however ON current increases due to wide tunneling window set up by gate potential for low source doping. OFF current and ambipolar conduction is increased by increasing drain doping concentration of SiNR TFET. read less NOT USED (low confidence) Y. Hong, J. Zhang, and X. Zeng, “Monolayer and bilayer polyaniline C3N: two-dimensional semiconductors with high thermal conductivity.,” Nanoscale. 2018. link Times cited: 71 Abstract: Polyaniline (PANI) has been extensively studied in the past … read moreAbstract: Polyaniline (PANI) has been extensively studied in the past few decades owing to its broad applications in electronic devices. However, two dimensional PANI was not realized until very recently. In this work, the thermal transport properties of one of the newly synthesized 2D PANI structures, C3N, are systematically investigated using classical molecular dynamics simulations. The in-plane thermal conductivity (κ) of monolayer and bilayer C3N structures is computed, and the κ values for infinite-length systems are found to be as high as 820 and 805 W m-1 K-1, respectively. Both the values are markedly higher than those of many prevailing 2D semiconducting materials such as phosphorene, hexagonal boron nitride, MoS2 and MoSe2. The effects of different modulators, such as system dimension, temperature, interlayer coupling strength and tensile strain, on the calculated thermal conductivity are evaluated. Monotonic decreasing trends of thermal conductivity with temperature and tensile strain are found, while a positive correlation between the thermal conductivity and system dimension is revealed. Interlayer coupling strength is found to have negligible effects on the in-plane thermal conductivity of bilayer C3N. The cross-plane interfacial thermal resistance (R) between two adjacent C3N layers is evaluated in the temperature range from 100 to 500 K and at different coupling strengths. The predicted R at temperature 300 K equals 3.4 × 10-8 K m-2 W-1. The maximum reductions of R can amount to 59% and 68% with respect to temperature and coupling strength, respectively. Our results provide theoretical guidance to future applications of C3N-based low-dimensional materials in electronic devices. read less NOT USED (low confidence) H. Fu, L. Gu, and D. Wu, “A spin-Seebeck diode with a negative differential spin-Seebeck effect in a hydrogen-terminated zigzag silicene nanoribbon heterojunction.,” Physical chemistry chemical physics : PCCP. 2016. link Times cited: 18 Abstract: The spin-Seebeck effect (SSE), the central topic of spin cal… read moreAbstract: The spin-Seebeck effect (SSE), the central topic of spin caloritronics, provides a new direction for future low power consumption technology. To realize device applications of SSE, a spin-Seebeck diode (SSD) with a negative differential SSE is very desirable. To this end, we constructed a spin caloritronics device that was composed of a ferromagnetic double-single-hydrogen-terminated zigzag silicene nanoribbon (ZSiNR-H2-H) and an antiferromagnetic double-double-hydrogen-terminated zigzag silicene nanoribbon (ZSiNR-H2-H2). By using ab initio calculations combined with nonequilibrium Green's function technique, we found that thermally driven spin current through the heterojunction featured the SSD effect and negative differential SSE. The former originates from the asymmetrical thermal-driven conducting electrons and holes, and the latter ascribes to the thermal spin compensation effect. Their physical mechanisms are much different from the previous ones mainly relying on the spin-wave excitations in the interface between metals and magnetic insulators, supporting our study that puts forward a new route to realize the SSD with a negative differential SSE. read less NOT USED (low confidence) H. Sadeghi and S. Sangtarash, “Silicene Nanoribbons and Nanopores for Nanoelectronic Devices and Applications.” 2017. link Times cited: 0 NOT USED (low confidence) M. E. Dávila, L. L. Y. Voon, J. Zhao, and G. L. Lay, “Elemental Group IV Two-Dimensional Materials Beyond Graphene,” Semiconductors and Semimetals. 2016. link Times cited: 9 NOT USED (low confidence) M. Hu, “Atomistic modeling of nanostructured materials for novel energy application.” 2015. link Times cited: 0 NOT USED (high confidence) M. Settipalli, V. S. Proshchenko, and S. Neogi, “Effect of Electron-Phonon and Electron-Impurity Scattering on Electronic Transport Properties of Silicon/Germanium Superlattices,” Journal of Materials Chemistry C. 2021. link Times cited: 2 Abstract: Semiconductor superlattices have been extensively investigat… read moreAbstract: Semiconductor superlattices have been extensively investigated for thermoelectric applications, to explore the effects of compositions, interface structures, and lattice strain environments on the reduction of thermal conductivity, and improvement of... read less NOT USED (high confidence) F. Zhang, X. Zheng, H. Wang, L. X. Ding, and G. Qin, “Anisotropy of thermal transport in phosphorene: A comparative first-principles study using different exchange-correlation functional,” Materials Advances. 2021. link Times cited: 0 Abstract: Phosphorene, as a new type of two-dimensional (2D) semicondu… read moreAbstract: Phosphorene, as a new type of two-dimensional (2D) semiconductor material, possesses unique physical and chemical properties, and thus has attracted widespread attention in recent years. With its increasing applications in... read less NOT USED (high confidence) B. Wei et al., “Giant Anisotropic in-Plane Thermal Conduction Induced by Anomalous Phonons in Pentagonal PdSe2,” Materials Today Physics. 2021. link Times cited: 6 NOT USED (high confidence) Z. Fan et al., “Neuroevolution machine learning potentials: Combining high accuracy and low cost in atomistic simulations and application to heat transport,” Physical Review B. 2021. link Times cited: 42 Abstract: We develop a neuroevolution-potential (NEP) framework for ge… read moreAbstract: We develop a neuroevolution-potential (NEP) framework for generating neural network based machine-learning potentials. They are trained using an evolutionary strategy for performing large-scale molecular dynamics (MD) simulations. A descriptor of the atomic environment is constructed based on Chebyshev and Legendre polynomials. The method is implemented in graphic processing units within the open-source GPUMD package, which can attain a computational speed over $10^7$ atom-step per second using one Nvidia Tesla V100. Furthermore, per-atom heat current is available in NEP, which paves the way for efficient and accurate MD simulations of heat transport in materials with strong phonon anharmonicity or spatial disorder, which usually cannot be accurately treated either with traditional empirical potentials or with perturbative methods. read less NOT USED (high confidence) B. Mortazavi, “Ultrahigh thermal conductivity and strength in direct-gap semiconducting graphene-like BC6N: A first-principles and classical investigation.” 2021. link Times cited: 35 NOT USED (high confidence) V. S. Proshchenko, M. Settipalli, A. Pimachev, and S. Neogi, “Role of substrate strain to tune energy bands–Seebeck relationship in semiconductor heterostructures,” Journal of Applied Physics. 2021. link Times cited: 5 Abstract: In doped semiconductors and metals, the Seebeck coefficient … read moreAbstract: In doped semiconductors and metals, the Seebeck coefficient or thermopower decreases monotonically with increasing carrier concentration in agreement with the Pisarenko relation. Here, we establish a fundamental mechanism to modulate and increase the thermopower of silicon (Si)/germanium (Ge) heterostructures beyond this relation, induced by the substrate strain. We illustrate the complex relationship between the lattice strain and the modulated thermopower by investigating the electronic structure and cross-plane transport properties of substrate strained [001] Si/Ge superlattices (SLs) with two independent theoretical modeling approaches: first-principles density functional theory and the analytical Kronig–Penny model in combination with the semi-classical Boltzmann transport equation. Our analysis shows that the SL bands, formed due to the cubic structural symmetry, combined with the potential perturbation and the intervalley mixing effects, are highly tunable with epitaxial substrate strain. The strain tuned energy band shifts lead to modulated thermopowers, with a peak approximately fivefold Seebeck enhancement in strained [001] Si/Ge SLs in the high-doping regime. As a consequence, the power factor of a 2.8% substrate strained SL shows a ≈ 1.8-fold improvement over bulk Si at high carrier concentrations, ≈ 12 × 10 20 cm − 3. It is expected that the fundamental understanding discussed here, regarding the complex effect of lattice strain to control energy bands of heterostructures, will help to exploit strain engineering strategies on a class of future technology-enabling materials, such as novel Si/Ge heterostructures as well as layered materials, including van der Waals heterostructures. read less NOT USED (high confidence) E. J. Guzmán, S. Molina-Valdovinos, O. Oubram, and I. Rodríguez-Vargas, “Enhancement of the Seebeck coefficient and power factor in gated silicene superlattices induced by aperiodicity,” Journal of Applied Physics. 2020. link Times cited: 4 Abstract: This paper theoretically investigates the impact of aperiodi… read moreAbstract: This paper theoretically investigates the impact of aperiodic sequences in the ballistic transport and thermoelectric effect in silicene gated superlattices. In our analysis, we have implemented the well-known Fibonacci, Thue–Morse, and triadic Cantor type sequences. The transfer matrix technique and the Landauer–Butikker formalism are used to calculate the transmission probability and the conductance, respectively. The Cutler–Mott formula is employed to estimate the Seebeck coefficient, and the thermoelectric power factor is then obtained. We found that the transmission minibands of aperiodic superlattices exhibit a much more fragmented structure in comparison to that reported in the periodic case. Consequently, the conductance curve presents a more pronounced oscillating shape, which improves the thermoelectric properties. In particular, the Seebeck coefficient has reached values up to 78.2 mV/K for Fibonacci, 233.0 mV/K for Thue–Morse, and 436.3 mV/K for Cantor. In addition, the power factor has been substantially increased, reaching peaks of approximately 8.2, 50.2, and 2.1 nW/K 2 for the mentioned sequences, respectively. The best results were obtained for s p i n d o w n ( s p i n u p) charge carriers in the K ( K ′) valley. Besides, an additional improvement is obtained by considering superior generations of the aperiodic sequences. Finally, our findings are supported through the redistribution of the density of the states, which is induced by the aperiodicity of the nanostructure as well as by the low-dimensionality of the thermoelectric device. read less NOT USED (high confidence) E. Chowdhury, M. Rahman, P. Bose, R. Jayan, and M. M. Islam, “Atomic-scale analysis of the physical strength and phonon transport mechanisms of monolayer β-bismuthene.,” Physical chemistry chemical physics : PCCP. 2020. link Times cited: 15 Abstract: Bismuthene has opened up a new avenue in the field of nanote… read moreAbstract: Bismuthene has opened up a new avenue in the field of nanotechnology because of its spectacular electronic and thermoelectric features. The strong spin-orbit-coupling enables its operation as the largest nontrivial bandgap topological insulator and quantum spin hall material at room temperature, which is unlikely for any other 2D material. It is also known to be the most promising thermoelectric material due to its remarkable thermoelectric properties, including a substantially high power factor. However, an in-depth understanding of the mechanical and thermal transport properties of bismuthene is crucial for its practical implementation and efficient operation. Employing the Stillinger-Weber potential, we utilized molecular dynamics simulations to inspect the mechanical strength and thermal conductivity of the monolayer β-bismuthene for the first time. We analyzed the effect of temperature on the tensile mechanical properties along the armchair and zigzag directions of bismuthene nanosheets and found that increasing temperature causes a significant deterioration in these properties. The material shows superior fracture resistance with zigzag loading, whereas the armchair direction exhibits an improved elasticity. Next, we showed that increasing vacancy concentration and crack length notably reduce the fracture stress and strain of β-bismuthene. Under all these conditions, β-bismuthene showed a strong chirality effect under tensile loading. We also explored the fracture phenomena of a pre-cracked β-bismuthene, which reveal that the armchair-directed crack possesses a higher fracture resistance than the zigzag-directed crack. Interestingly, branching phenomena occurred during crack propagation for the armchair crack; meanwhile, the crack propagates perpendicular to loading for the zigzag crack. Afterward, we investigated the effect of loading rate on the fracture properties of bismuthene along the armchair and zigzag directions. Finally, we calculated the thermal conductivity of bismuthene under the influence of temperature and vacancy and recorded a substantial decrement in thermal conductivity with increasing temperature and vacancy. The obtained results are comprehensively discussed in the light of phonon density of states, phonon dispersion spectrum, and phonon group velocities. It is also disclosed that the thermal conductivity of β-bismuthene is considerably lower than that of other analogous honeycomb structures. This study can add a new dimension to the successful realization of bismuthene in future (opto)electronic, spintronic, and thermoelectric devices. read less NOT USED (high confidence) X.-K. Chen, Y. Zeng, and K. Chen, “Thermal Transport in Two-Dimensional Heterostructures,” Frontiers in Materials. 2020. link Times cited: 18 Abstract: Heterostructures based on two-dimensional (2D) materials hav… read moreAbstract: Heterostructures based on two-dimensional (2D) materials have attracted intense attention in recent decades due to their unusual and tunable physics/chemical properties, which can be converted into promising engineering applications ranging from electronics, photonics, and phononics to energy recovery. A fundamental understanding of thermal transport in 2D heterostructures is crucial importance for developing micro-nano devices based on them. In this review, we summarized the recent advances of thermal transport in 2D heterostructures. Firstly, we introduced diverse theoretical approaches and experimental techniques for thermal transport in low-dimensional materials. Then we briefly reviewed the thermal properties of various 2D single-phase materials beyond graphene such as hexagonal boron nitride (h-BN), phosphorene, transition metal dichalcogenides (TMDs) and borophene, and emphatically discussed various influencing factors including structural defects, mechanical strain, and substrate interactions. Moreover, we highlighted thermal conduction control in tailored nanosystems—2D heterostructures and presented the associated underlying physical mechanisms, especially interface-modulated phonon dynamics. Finally, we outline their significant applications in advanced thermal management and thermoelectrics conversion, and discuss a number of open problems on thermal transport in 2D heterostructures. read less NOT USED (high confidence) V. Kumar and D. R. Roy, “Strain-induced band modulation and excellent stability, transport and optical properties of penta-MP2 (M = Ni, Pd, and Pt) monolayers,” Nanoscale Advances. 2020. link Times cited: 10 Abstract: First principle calculations utilizing density functional th… read moreAbstract: First principle calculations utilizing density functional theory were carried out to investigate the electronic, transport and optical properties of penta-MP2 (M = Ni, Pd and Pt) monolayer compounds under applied uniaxial and biaxial tensile strains. With an optimum magnitude of applied strain, we found band gap transitions in penta-MP2 monolayers from zero/narrow to the semiconductor regime, wherein band gaps were noticed to be firmly dependent on the applied uniaxial and biaxial tensile strains. In this study, the PBE approach was used primarily to evaluate electronic properties, from where the identified architectures of penta-MP2 with maximum obtained bandgaps under respective optimum strains were assessed through the HSE06 method of calculation for better estimation of band gaps and optical properties. Prior to HSE calculations, we affirmed our assessment for the stability and reliability of the compounds under uniaxial and biaxial strains of up to 15% through phonon spectrum and elastic calculations. A distinct transition was also noted from semiconductor to metal for all compounds after the applied optimum uniaxial and biaxial strains. The optical absorption spectra in all the stretched penta-MP2 compounds reached the order of 106 cm−1, with significant peaks belonging to the IR and visible regions; this indicates promising applications of these materials in high-performance solar energy and good hot mirror materials. The enhanced I–V responses under uniaxial and biaxial tensile strains using the non-equilibrium Green's function (NEGF) approach confirm the usefulness of the strained state of the considered penta-MP2 monolayers. The results show that tuning electronic properties, I–V characteristics and optical properties of stretched penta-MP2 compounds under tensile strain merits significant future applications in optoelectronic devices and as good hot mirror materials. read less NOT USED (high confidence) N. R. Abdullah, H. Rashid, C. Tang, A. Manolescu, and V. Gudmundsson, “Properties of BSi6N monolayers derived by first-principle computation,” arXiv: Materials Science. 2020. link Times cited: 18 NOT USED (high confidence) M. A. Z. Mamun, A. A. Mohaimen, and S. Subrina, “Tunable thermal conductivity of single layer MoS2 nanoribbons: an equilibrium molecular dynamics study,” Journal of Computational Electronics. 2020. link Times cited: 3 NOT USED (high confidence) A. Islam, M. S. Islam, N. Ferdous, J. Park, and A. Hashimoto, “Vacancy-induced thermal transport in two-dimensional silicon carbide: a reverse non-equilibrium molecular dynamics study.,” Physical chemistry chemical physics : PCCP. 2020. link Times cited: 23 Abstract: Because of its impressive electrical, thermal, and mechanica… read moreAbstract: Because of its impressive electrical, thermal, and mechanical properties, two-dimensional silicon carbide (2D-SiC) has recently gained tremendous attention in the field of nanoelectronics and optoelectronics. Here, we investigated the effects of various types of defects such as bi-, point-, and mixed-vacancies on the thermal conductivity of 2D-SiC using reverse non-equilibrium molecular dynamics simulation. The effects of temperature variation on the thermal conductivity of vacancy-defected 2D-SiC were also studied. A significant reduction of the thermal conductivity was observed when the concentrations of the vacancies were increased. The point vacancy resulted in the thermal conductivity decreasing more quickly as compared to bi vacancy and mixed vacancy defects. Moreover, increasing the temperature of vacancy-defected 2D-SiC further reduced the thermal conductivity due to a strong phonon-vacancy scattering effect. Because of the introduction of vacancy defects in the acoustic phonon density of states (PDOS), a softening behavior in the intensity of the characteristic peaks is perceived, and with increasing temperature, a frequency shrinking is noted in the PDOS curves, both of which contribute to the reduction of the thermal conductivity. Additionally, rapid softening of the phonon transmission spectrum and increase in entropy were obtained for the point vacancy-defected structure, which clearly confirms our findings at different vacancy concentrations as well as for types of vacancies. These findings are very much imperative for realizing heat dissipation in nano- and optoelectronic devices based on 2D-SiC as well as for demonstrating an effective method for modulating 2D-SiC thermal conductivity through defect engineering. read less NOT USED (high confidence) M. Abdi and B. Astinchap, “Influence of Magnetic Field and Bias Voltage on the Thermal Conductivity and Seebeck Coefficient of AA-Stacked Bilayer SiC,” Silicon. 2020. link Times cited: 4 NOT USED (high confidence) V. V. Hoang, N. H. Giang, and T. Q. Dong, “Amorphous and ‘crystalline’ penta-silicene,” Philosophical Magazine. 2020. link Times cited: 2 Abstract: ABSTRACT Atomic structure, thermodynamic and mechanical beha… read moreAbstract: ABSTRACT Atomic structure, thermodynamic and mechanical behaviours of the penta-silicene (p-silicene) obtained by cooling from the melt are studied by the molecular dynamics (MD) simulations. We find that p-silicene can ‘naturally’ form from the liquid state using the appropriate interatomic potential, density and buckling. The charge-optimised many body (COMB) potential is employed. Depending on the cooling rate used in simulations, ‘crystalline’ or amorphous p-silicene can be obtained. ‘Crystallisation’ and glass transition temperatures ( and , respectively) have reasonable values compared to those of the hexa-silicene (h-silicene). We find that the Poisson’s ratio of the obtained ‘crystalline’ p-silicene is positive unlike the negative one found for the p-graphene. The reasons for the formation of p-silicene instead of tetra-silicene (t-silicene) are analysed and discussed, i.e. 2D liquid silicene with COMB potential has a significant fraction of pentagons which grow with decreasing temperature, unlike 2D liquid silicene with the Stillinger–Weber potential. read less NOT USED (high confidence) Y. Yin, D. Li, Y. Hu, G. Ding, H. Zhou, and G. Zhang, “Phonon stability and phonon transport of graphene-like borophene,” Nanotechnology. 2020. link Times cited: 31 Abstract: Recent decades have seen tremendous progress in quantitative… read moreAbstract: Recent decades have seen tremendous progress in quantitative understanding of phonon transport, which is critical for the thermal management of various functional devices and the proper optimization of thermoelectric materials. In this work, using a first-principles based calculation combined with the non-equilibrium Green’s function and a phonon Boltzmann transport equation, we provide a systematic study of the phonon stability and phonon transport of a monolayer boron sheet with a honeycomb, graphene-like structure (graphene-like borophene) in both ballistic and diffusive regimes. For free-standing graphene-like borophene, phonon instabilities occur near the centre of the Brillouin zone, implying elastic instability. Investigation of the electronic structures shows that the phonon instability is due to the deficiency of electrons. Our first-principles results show that with net charge doping and in-plane tensile strain, graphene-like borophene becomes thermodynamically stable in ideal planar nature, because the bonding characteristic is modified. At room temperature, the ballistic thermal conductance of graphene-like borophene (7.14 nWK−1 nm−2) is higher than that of graphene (4.1 nWK−1 nm−2), due to high phonon transmission. However, its diffusive thermal conductivity is two orders of magnitude lower than graphene, because the phonon relaxation time is dramatically reduced compared with its carbon counterpart. Although the phonon group velocity and phonon anharmonicity are comparable with those of graphene, the suppressed phonon space results in dramatically strong phonon–phonon scattering. These thermal transport characteristics in both ballistic and diffusive regimes are of fundamental and technological relevance and provide guidance for applications of boron-based nanomaterials in which thermal conduction is the major concern. read less NOT USED (high confidence) V. V. Hoang, N. H. Giang, and V. Bubanja, “Hexa ↔ tetra silicene crystal–crystal phase transition,” Philosophical Magazine. 2020. link Times cited: 4 Abstract: ABSTRACT Formation of confined crystalline tetra-silicene (t… read moreAbstract: ABSTRACT Formation of confined crystalline tetra-silicene (t-silicene) from crystalline hexa-silicene (h-silicene) via compression, and the reverse transition from the obtained t-silicene to h-silicene via heating, are studied by molecular dynamics (MD) simulations. Models contain 6400 Si atoms interacted via the new version of the Stillinger-Weber potential. While t-silicene can be obtained via compression of the crystalline h-silicene at various temperatures, we find that the best quality samples (with the highest fraction of tetragons) are obtained at high temperatures but still well below the melting point. Such t-silicene is stable over a wide range of pressure and temperature. Evolution of the structural characteristics of samples and various thermodynamic quantities upon compression is studied. Detailed analysis of the structure of t-silicene at 300 K is presented via radial distribution function, coordination number and bond-angle distributions, ring statistics and interatomic distance distribution, as well as 2D visualisation of the atomic configurations. Various types of structural defects of t-silicene are found and discussed. In addition, heating of the obtained t-silicene is shown to lead first to the reverse tetra-to-hexa silicene phase transition, and then to the melting of h-silicene. Evolution of the structural characteristics of the samples and of the thermodynamic quantities upon heating are considered. Atomic mechanism underlaying the tetrahexa phase transitions is discussed. read less NOT USED (high confidence) J. Ma, J.-J. Zheng, W. Li, D.-hong Wang, and B.-T. Wang, “Thermal transport properties of monolayer MoSe2 with defects.,” Physical chemistry chemical physics : PCCP. 2020. link Times cited: 11 Abstract: Two-dimensional (2D) molybdenum diselenide (MoSe2) as one of… read moreAbstract: Two-dimensional (2D) molybdenum diselenide (MoSe2) as one of the ultrathin transition metal dichalcogenides (TMDs) has attracted considerable attention because of its potential applications in thermoelectric and nano-electronic devices. Here, the thermal conductivity of monolayer MoSe2 and its responses to simulated size and defects are studied by nonequilibrium molecular dynamics simulations. With the increase of sample length, the thermal conductivity of monolayer MoSe2 nanoribbons exhibits an enhancement whereas it is insensitive to the width. At room temperature, the thermal conductivities of monolayer MoSe2 along armchair and zigzag directions are 17.758 and 18.932 W (m K)-1, respectively, which are consistent with previous results. The impact of defects on thermal conductivity has also been studied by varying the concentration of the vacancy from 0.1% to 0.5%. The results show that an increase of the defect concentration will greatly suppress the thermal conductivity. The 0.5% defect concentration with a Mo vacancy can result in a thermal conductivity reduction of ∼43%. Such a study would provide a good insight into the tunable thermal transport for potential applications of not only monolayer MoSe2, but also many other TMDs. read less NOT USED (high confidence) C. Zhang and Q. Sun, “Gaussian approximation potential for studying the thermal conductivity of silicene,” Journal of Applied Physics. 2019. link Times cited: 22 Abstract: Due to the compatibility with the well-developed Si-based se… read moreAbstract: Due to the compatibility with the well-developed Si-based semiconductor technology, the properties of silicene and silicene-based materials have attracted tremendous attention. Among them, the thermal conductivity (TC) is of special importance for electronic devices. However, unlike graphene, the poor quality of empirical potentials hinders the reliable evaluation of TC for silicene using molecular dynamics (MD). Here, we present a Gaussian approximation potential (GAP) for silicene based on ab initio derived training data. The potential can precisely describe the geometries, mechanical properties, as well as phonon dispersion of free-standing sheet, outperforming any other empirical ones. Using sinusoidal approach-to-equilibrium MD simulations based on the GAP potential, the TC of silicene is found to be 32.4 ± 2.9 W / m K at room temperature. Importantly, our result achieves a good agreement with Boltzmann transport equation (BTE) based first-principles predictions ( ∼ 30 W / m K), such that the TC value of silicene is confirmed via both MD and BTE; thus, we prove that the accuracy of machine learning potentials, like GAP, can enable a faithful prediction of TC at a density functional theory (DFT) level.Due to the compatibility with the well-developed Si-based semiconductor technology, the properties of silicene and silicene-based materials have attracted tremendous attention. Among them, the thermal conductivity (TC) is of special importance for electronic devices. However, unlike graphene, the poor quality of empirical potentials hinders the reliable evaluation of TC for silicene using molecular dynamics (MD). Here, we present a Gaussian approximation potential (GAP) for silicene based on ab initio derived training data. The potential can precisely describe the geometries, mechanical properties, as well as phonon dispersion of free-standing sheet, outperforming any other empirical ones. Using sinusoidal approach-to-equilibrium MD simulations based on the GAP potential, the TC of silicene is found to be 32.4 ± 2.9 W / m K at room temperature. Importantly, our result achieves a good agreement with Boltzmann transport equation (BTE) based first-principles predictions ( ∼ 30 W / m K), such that ... read less NOT USED (high confidence) A. Islam et al., “Anomalous temperature dependent thermal conductivity of two-dimensional silicon carbide,” Nanotechnology. 2019. link Times cited: 46 Abstract: Recently, two-dimensional silicon carbide (2D-SiC) has attra… read moreAbstract: Recently, two-dimensional silicon carbide (2D-SiC) has attracted considerable interest due to its exotic electronic and optical properties. Here, we explore the thermal properties of 2D-SiC using reverse non-equilibrium molecular dynamics simulation. At room temperature, a thermal conductivity of ∼313 W mK−1 is obtained for 2D-SiC which is one order higher than that of silicene. Above room temperature, the thermal conductivity deviates the normal 1/T law and shows an anomalous slowly decreasing behavior. To elucidate the variation of thermal conductivity, the phonon modes at different length and temperature are quantified using Fourier transform of the velocity auto-correlation of atoms. The calculated phonon density of states at high temperature shows a shrinking and softening of the peaks, which induces the anomaly in the thermal conductivity. On the other hand, quantum corrections are applied to avoid the freezing effects of phonon modes on the thermal conductivity at low temperature. In addition, the effect of potential on the thermal conductivity calculation is also studied by employing original and optimized Tersoff potentials. These findings provide a means for better understating as well as designing the efficient thermal management of 2D-SiC based electronics and optoelectronics in near future. read less NOT USED (high confidence) E. Zhang, Y.-H. Yao, T. Gao, D. Kang, J. Wu, and J. Dai, “The effect of external temperature gradients on thermal conductivity in non-equilibrium molecular dynamics simulations: From nanowires to bulk Si,” The Journal of Chemical Physics. 2019. link Times cited: 6 Abstract: Nonequilibrium molecular dynamics is widely used to calculat… read moreAbstract: Nonequilibrium molecular dynamics is widely used to calculate the thermal conductivity of various materials, but the influence of temperature gradient to thermal conductivity has received limited attention within current research studies. The purpose of this article is to explore the discrepancy between intrinsic and extrinsic thermal conductivities under different temperature gradients, which can be considered as external fields. The analyses of phonon density of states have shown that the temperature gradient plays a role in the external field, and a larger temperature gradient activates more low-frequency vibrational modes, which leads to larger thermal conductivities. Specially, the thermal conductivity increases linearly with the temperature gradient when using Stillinger-Weber (SW) potential. Moreover, a new formula was derived to satisfactorily fit the thermal conductivities of bulk Si and silicon nanowires (SiNWs) for various cell sizes, and the physical meaning of the formula was explained. It is shown that the SW potential and Tersoff potential of Si produce different thermal conductivities. By comparing the results of first principles simulations, the Tersoff potential gives rise to better description of vibrational modes. read less NOT USED (high confidence) S. Sahoo and K. Wei, “A Perspective on Recent Advances in 2D Stanene Nanosheets,” Advanced Materials Interfaces. 2019. link Times cited: 50 Abstract: Advancements in 2D nanomaterials have been impacting a wide … read moreAbstract: Advancements in 2D nanomaterials have been impacting a wide range of technology‐driven applications. Here, the authors highlight stanene, a material that comprises a monolayer of elemental tin atoms, as a new addition to the monoelemental 2D family. Recent successes in the experimental realization of stanene in supported heterostructures and in free‐standing form have expanded interest in exploring and unlocking its potential applications, as predicted from advanced theoretical calculations. Stanene exhibits several remarkable features, including a large spin–orbit gap (allowing room‐temperature electronics based on the quantum spin Hall effect), topological superconductivity, quantum anomalous Hall behavior, giant magnetoresistance, and efficient thermoelectricity. Research into stanene and stanene‐based 2D materials, both experimentally and theoretically, is suggesting immense potential for future quantum‐based electronics systems. Here, the fundamental features of stanene, progress in its synthesis, and future perspectives are discussed. read less NOT USED (high confidence) Z. Sun, K. Yuan, X. Zhang, G. Qin, X. Gong, and D. Tang, “Disparate strain response of the thermal transport properties of bilayer penta-graphene as compared to that of monolayer penta-graphene.,” Physical chemistry chemical physics : PCCP. 2019. link Times cited: 13 Abstract: In this study, strain modulation of the lattice thermal cond… read moreAbstract: In this study, strain modulation of the lattice thermal conductivity of monolayer and bilayer penta-graphene (PG) at room temperature was investigated using first-principles calculations combined with the phonon Boltzmann transport equation. The thermal conductivities of both the monolayer and the bilayer PG exhibit a robust nonmonotonic up-and-down behavior under strain despite the effect of van der Waals (vdW) interactions, and the thermal conductivities of bilayer PG under strain are significantly reduced by up to 87%. Using phonon-level systematic analysis, the variation of thermal conductivity with the increasing strain was determined by increasing the phonon lifetime in specific phonon modes, and that with the reduction of strain was determined by the decrease of both phonon group velocity and phonon lifetime. Moreover, bilayer PG shows an unexpectedly different response to strain when compared with monolayer PG, and a significantly larger reduction (>60%) in the thermal conductivity of bilayer PG is achieved when the strain reaches 10% because the interlayer interactions enhance the phonon anharmonicity of the phonon modes of ultra-low frequency. Our study shows that bilayer PG will have tremendous opportunities for application in thermal management and two-dimensional nanoscale electronic devices owing to its largely tunable thermal conductivity. read less NOT USED (high confidence) B. Mortazavi, M. Madjet, M. Shahrokhi, S. Ahzi, X. Zhuang, and T. Rabczuk, “Nanoporous graphene: A 2D semiconductor with anisotropic mechanical, optical and thermal conduction properties,” Carbon. 2019. link Times cited: 43 NOT USED (high confidence) W.-L. Tao, Y. Mu, C.-E. Hu, Y. Cheng, and G. Ji, “Electronic structure, optical properties, and phonon transport in Janus monolayer PtSSe via first-principles study,” Philosophical Magazine. 2019. link Times cited: 49 Abstract: ABSTRACT Motivated by the synthesis of a Janus monolayer, th… read moreAbstract: ABSTRACT Motivated by the synthesis of a Janus monolayer, the new PtSSe transition-metal dichalcogenide (TMD) have attracted remarkable attention due to their characteristic properties. In this work, we calculated the electronic structure, optical properties, and the thermal conductivity of the PtSSe monolayers, and performed a detailed comparison with other TMDs (monolayer PtS2 and PtSe2) using first-principles calculations. The calculated band gaps of the PtS2, PtSSe, and PtSe2 monolayers were 1.76, 1.38, and 1.21 eV, respectively, which are in good agreement with experimental data. At the same time, we observed a larger spin-orbit splitting in the electronic structure of PtSSe monolayers. The optical properties were also calculated and a significant red shift was observed from the PtS2 to PtSSe to PtSe2 monolayers. The lattice thermal conductivity of the PtSSe monolayer at room temperature (36.19 W/mK) is significantly lower than that of the PtS2 monolayer (54.25 W/mK) and higher than that of the PtSe2 monolayer (18.07 W/mK). Our results show that the PtSSe monolayer breaks structural symmetry and has the same ability to reduce the thermal conductivity as MoSSe and ZrSSe monolayers due to the shorter group velocity and the lower converged phonon scattering rate. These results may stimulate further studies on the electronic structure, optical properties, and thermal conductivity of the PtSSe monolayer in both experimental synthesis and theoretical efforts. read less NOT USED (high confidence) Y. Lysogorskiy, T. Hammerschmidt, J. Janssen, J. Neugebauer, and R. Drautz, “Transferability of interatomic potentials for molybdenum and silicon,” Modelling and Simulation in Materials Science and Engineering. 2019. link Times cited: 14 Abstract: Interatomic potentials are widely used in computational mate… read moreAbstract: Interatomic potentials are widely used in computational materials science, in particular for simulations that are too computationally expensive for density functional theory (DFT). Most interatomic potentials have a limited application range and often there is very limited information available regarding their performance for specific simulations. We carried out high-throughput calculations for molybdenum and silicon with DFT and a number of interatomic potentials. We compare the DFT reference calculations and experimental data to the predictions of the interatomic potentials. We focus on a large number of basic materials properties, including the cohesive energy, atomic volume, elastic coefficients, vibrational properties, thermodynamic properties, surface energies and vacancy formation energies, which enables a detailed discussion of the performance of the different potentials. We further analyze correlations between properties as obtained from DFT calculations and how interatomic potentials reproduce these correlations, and suggest a general measure for quantifying the accuracy and transferability of an interatomic potential. From our analysis we do not establish a clearcut ranking of the potentials as each potential has its strengths and weaknesses. It is therefore essential to assess the properties of a potential carefully before application of the potential in a specific simulation. The data presented here will be useful for selecting a potential for simulations of Mo or Si. read less NOT USED (high confidence) D. Han et al., “Phonon thermal conduction in a graphene–C3N heterobilayer using molecular dynamics simulations,” Nanotechnology. 2018. link Times cited: 51 Abstract: Two-dimensional (2D) graphene (GRA) and polyaniline (C3N) mo… read moreAbstract: Two-dimensional (2D) graphene (GRA) and polyaniline (C3N) monolayers are attracting growing research interest due to their excellent electrical and thermal properties. In this work, in-plane and out-of-plane phonon thermal conduction of GRA–C3N heterobilayer are systematically investigated by using classical molecular dynamics simulations. Effects of system size, temperature and interlayer coupling strength on the in-plane thermal conductivity (k) and out-of-plane interfacial thermal resistance (R) are evaluated. Firstly, a monotonic increasing trend of k with increasing system size is observed, while a negative correlation between thermal conductivity and temperature is revealed. The interlayer coupling strength is found to have a weak effect on the in-plane thermal conductivity of the heterobilayer. Secondly, at T = 300 K and χ = 1, the predicted R of GRA → C3N and C3N → GRA are 1.29 × 10−7 K m2 W−1 and 1.35 × 10−7 K m2 W−1, respectively, which indicates that there is no significant thermal rectification phenomenon. It can also be observed that R decreases monotonically with increasing temperature and coupling strength due to the enhanced Umklapp phonon scattering and the phonon transmission probability across the interface. Phonon density of states, phonon dispersions and participation ratios are evaluated to reveal the mechanism of heat conduction in the heterobilayer. This work contributes the valuable thermal information to modulate the phonon behaviors in 2D heterobilayer based nanoelectronics. read less NOT USED (high confidence) N. Jahan, I. A. Navid, and S. Subrina, “Thermal Conductivity of Silicene Nanoribbons: An Equilibrium Molecular Dynamics Study,” 2018 IEEE International WIE Conference on Electrical and Computer Engineering (WIECON-ECE). 2018. link Times cited: 6 Abstract: In order to gain insight into the thermal transport properti… read moreAbstract: In order to gain insight into the thermal transport properties of silicene nanoribbon (SiNR), we compute the thermal conductivity of both armchair and zigzag SiNRs using Equilibrium Molecular Dynamics (EMD) simulation. Applying Modified Embedded Atom Method (MEAM) potential, the room temperature thermal conductivities of 10 nm × 2 nm armchair and zigzag silicene nanoribbon are estimated to be 2.52 W/m-K and 2.59 W/m-K, respectively. We also investigate SiNR's thermal conductivity as a function of ribbon length, width and temperature. For both armchair and zigzag SiNRs, increasing length and width have a positive effect on thermal conductivity but for increasing temperature, it shows a decreasing trend. The very low thermal conductivity of SiNR validates the conclusion that it is a potential thermo-electric material and our study will be helpful for its use in modern small-scale silicene-based device. read less NOT USED (high confidence) T. Ouyang, E. Jiang, C. Tang, J. Li, C. He, and J. Zhong, “Thermal and thermoelectric properties of monolayer indium triphosphide (InP3): a first-principles study,” Journal of Materials Chemistry. 2018. link Times cited: 65 Abstract: Monolayer indium triphosphide (InP3) is a newly predicted 2D… read moreAbstract: Monolayer indium triphosphide (InP3) is a newly predicted 2D material with a quasi-direct electronic band gap which is predicted to exhibit fascinating adsorption efficiency, foreshadowing its potential applications in the photovoltaic and optoelectronic communities. To achieve a combination of photovoltaic and thermoelectric technologies and further boost the energy utilization rate, in this paper we systematically investigate the thermal and thermoelectric properties through combining first-principles calculations and semiclassical Boltzmann transport theory. Our calculations show that the average lattice thermal conductivity of monolayer InP3 is about 0.63 W mK−1 at room temperature, which is comparable to that of classical thermoelectric materials. Such a poor phonon transport property mainly originates from its smaller group velocity and stronger phonon–phonon scattering (including both scattering magnitude and channels). Unlike the isotopic phonon transport property, the electronic conductivity and electronic thermal conductivity of monolayer InP3 present obvious anisotropic behavior. Meanwhile, a high Seebeck coefficient is also predicted in monolayer InP3 with both n- and p-type doping due to the large electronic band gap and sharp increase in electronic conductivity. By using the electron relaxation time estimated from deformation potential theory, the room temperature thermoelectric figure of merit of monolayer InP3 is found to be as high as 2.06 (with p-type doping) and 0.61 (with n-type doping) along the armchair and zigzag directions, which are substantially larger than for black phosphorene (ZT ∼ 0.4 at room temperature). The results presented in this work shed light on the thermoelectric performance of monolayer InP3 and qualify its potential application in a multifunction device that contains both photovoltaic and thermoelectric technologies. read less NOT USED (high confidence) I. Navid and S. Subrina, “Thermal transport characterization of carbon and silicon doped stanene nanoribbon: an equilibrium molecular dynamics study,” RSC Advances. 2018. link Times cited: 12 Abstract: Equilibrium molecular dynamics simulation has been carried o… read moreAbstract: Equilibrium molecular dynamics simulation has been carried out for the thermal transport characterization of nanometer sized carbon and silicon doped stanene nanoribbon (STNR). The thermal conduction properties of doped stanene nanostructures are yet to be explored and hence in this study, we have investigated the impact of carbon and silicon doping concentrations as well as doping patterns namely single doping, double doping and edge doping on the thermal conductivity of nanometer sized zigzag STNR. The room temperature thermal conductivities of 15 nm × 4 nm doped zigzag STNR at 2% carbon and silicon doping concentration are computed to be 9.31 ± 0.33 W m−1 K−1 and 7.57 ± 0.48 W m−1 K−1, respectively whereas the thermal conductivity for the pristine STNR of the same dimension is calculated as 1.204 ± 0.21 W m−1 K−1. We find that the thermal conductivity of both carbon and silicon doped STNR increases with the increasing doping concentration for both carbon and silicon doping. The magnitude of increase in STNR thermal conductivity due to carbon doping has been found to be greater than that of silicon doping. Different doping patterns manifest different degrees of change in doped STNR thermal conductivity. Double doping pattern for both carbon and silicon doping induces the largest extent of enhancement in doped STNR thermal conductivity followed by single doping pattern and edge doping pattern respectively. The temperature and width dependence of doped STNR thermal conductivity has also been studied. For a particular doping concentration, the thermal conductivity of both carbon and silicon doped STNR shows a monotonic decaying trend at elevated temperatures while an opposite pattern is observed for width variation i.e. thermal conductivity increases with the increase in ribbon width. Such comprehensive study on doped stanene would encourage further investigation on the proper optimization of thermal transport characteristics of stanene nanostructures and provide deep insight in realizing the potential application of doped STNR in thermoelectric as well as thermal management of stanene based nanoelectronic devices. read less NOT USED (high confidence) S. Nahid, S. Nahian, M. Motalab, T. Rakib, S. Mojumder, and M. M. Islam, “Tuning the mechanical properties of silicene nanosheet by auxiliary cracks: a molecular dynamics study,” RSC Advances. 2018. link Times cited: 17 Abstract: Silicene has become a topic of interest nowadays due to its … read moreAbstract: Silicene has become a topic of interest nowadays due to its potential application in various electro-mechanical nanodevices. In our previous work on silicene, fracture stresses of single crystal and polycrystalline silicene have been investigated. Existence of defects in the form of cracks reduces the fracture strength of silicene nanosheets to a great extent. In this study, an engineering way has been proposed for improving the fracture stress of silicene nanosheets with a pre-existing crack by incorporating auxiliary cracks symmetrically in a direction perpendicular to the main crack. We call this mechanism the “Failure shielding mechanism”. An extensive molecular dynamics simulation based analysis has been performed to capture the atomic level auxiliary crack-main crack interactions. It is found that the main crack tip stress distribution is significantly changed with the presence of auxiliary cracks for loading along both armchair and zigzag directions. The effects of temperature and the crack propagation speed of silicene have also been studied. Interestingly, in the case of loading along the zigzag direction, SW defect formation is observed at the tip of main crack. This leads to a reduction of the tip stress resulting in a more prominent failure shielding in case of zigzag loading than in armchair loading. Moreover, the position and length of the cracks as well as the loading directions have significant impacts on the tip stress distribution. Finally, this study opens the possibilities of strain engineering for silicene by proposing an engineering way to tailor the fracture strength of silicene. read less NOT USED (high confidence) X. Tan, D. Wu, Q.-bo Liu, H. Fu, and R. Wu, “Spin caloritronics in armchair silicene nanoribbons with sp3 and sp2-type alternating hybridizations,” Journal of Physics: Condensed Matter. 2018. link Times cited: 9 Abstract: Finite-layer nanoribbon materials have long been considered … read moreAbstract: Finite-layer nanoribbon materials have long been considered as potential candidates for nanodevices with novel quantum effects. Here we constructed a series of ferromagnetic armchair silicene nanoribbons (ASiNRs) with sp3 and sp2-type alternating hybridizations, and found that the ASiNRs with different widths are localized in different spin-resolved electronic states. As the width parameter N is increased from 5 to 22, the ASiNR transits from indirect-gap half metallicity (HM), to indirect-gap spin semiconductor (SC), then to direct-gap SC and finally to direct-gap HM. When a temperature gradient is produced along the nanoribbons, the spin-dependent currents with the opposite flow directions are driven and a nearly perfect spin-dependent Seebeck effect (SDSE) occurs. Moreover, attributing to symmetrical spin-resolved transport channels, nearly pure thermal spin current without any accompanying charge current can be generated. In addition, for some ASiNRs with proper widths, both the thermal spin-up current and spin-down one are contributed by the electrons in energy valleys, resulting in a well-defined valley-dependent SDSE. These theoretical findings suggest that the ASiNRs with the sp3 and sp2-type alternating hybridizations can be outstanding candidates for future spin caloritronic devices. read less NOT USED (high confidence) M. Vohra, A. Nobakht, S. Shin, and S. Mahadevan, “Uncertainty quantification in non-equilibrium molecular dynamics simulations of thermal transport,” International Journal of Heat and Mass Transfer. 2018. link Times cited: 14 NOT USED (high confidence) A. Bourque and G. Rutledge, “Empirical potential for molecular simulation of graphene nanoplatelets.,” The Journal of chemical physics. 2018. link Times cited: 8 Abstract: A new empirical potential for layered graphitic materials is… read moreAbstract: A new empirical potential for layered graphitic materials is reported. Interatomic interactions within a single graphene sheet are modeled using a Stillinger-Weber potential. Interatomic interactions between atoms in different sheets of graphene in the nanoplatelet are modeled using a Lennard-Jones interaction potential. The potential is validated by comparing molecular dynamics simulations of tensile deformation with the reported elastic constants for graphite. The graphite is found to fracture into graphene nanoplatelets when subjected to ∼15% tensile strain normal to the basal surface of the graphene stack, with an ultimate stress of 2.0 GPa and toughness of 0.33 GPa. This force field is useful to model molecular interactions in an important class of composite systems comprising 2D materials like graphene and multi-layer graphene nanoplatelets. read less NOT USED (high confidence) A. Bhattacharya, P. R. Raghuvansi, and G. P. Das, “The origin of diverse lattice dynamics in the graphene family,” Journal of Physics: Condensed Matter. 2018. link Times cited: 3 Abstract: We employ first principles based density functional theory c… read moreAbstract: We employ first principles based density functional theory calculations to explore the lattice dynamics of members of the graphene family. We explore the changes observed in the lattice thermal conductivity via adopting physical models for estimating phonon lifetimes. This allows us to establish a connection between the parameters such as group velocity, Grüneisen parameter, and Debye temperature of the acoustic phonon modes and the lattice thermal conductivity. Our calculations show that the presence of buckling reduces the group velocity and the Debye temperature of the sheets down the group, and hence, reduces their lattice thermal conductivity. However, there is no linear dependence between the buckling height and the observed lowering. An increase in buckling height in sheets with different geometries of the same atomic species, beyond a certain limit, does not lead to change in the group velocity and the Debye temperature of the sheets. read less NOT USED (high confidence) Y. Hong, J. Zhang, and X. Zeng, “Thermal transport in phosphorene and phosphorene-based materials: A review on numerical studies,” Chinese Physics B. 2018. link Times cited: 19 NOT USED (high confidence) M. Z. Hossain, T. Hao, and B. Silverman, “Stillinger–Weber potential for elastic and fracture properties in graphene and carbon nanotubes,” Journal of Physics: Condensed Matter. 2018. link Times cited: 42 Abstract: This paper presents a new framework for determining the Stil… read moreAbstract: This paper presents a new framework for determining the Stillinger–Weber (SW) potential parameters for modeling fracture in graphene and carbon nanotubes. In addition to fitting the equilibrium material properties, the approach allows fitting the potential to the forcing behavior as well as the mechanical strength of the solid, without requiring ad hoc modification of the nearest-neighbor interactions for avoiding artificial stiffening of the lattice at larger deformation. Consistent with the first-principles results, the potential shows the Young’s modulus of graphene to be isotropic under symmetry-preserving and symmetry-breaking deformation conditions. It also shows the Young’s modulus of carbon nanotubes to be diameter-dependent under symmetry-breaking loading conditions. The potential addresses the key deficiency of existing empirical potentials in reproducing experimentally observed glass-like brittle fracture in graphene and carbon nanotubes. In simulating the entire deformation process leading to fracture, the SW-potential costs several factors less computational time compared to the state-of-the-art interatomic potentials that enables exploration of the fracture processes in large atomistic systems which are inaccessible otherwise. read less NOT USED (high confidence) G. Qin and M. Hu, “Thermal transport properties of monolayer phosphorene: a mini-review of theoretical studies,” Frontiers in Energy. 2018. link Times cited: 6 NOT USED (high confidence) M. Barati, T. Vazifehshenas, T. Salavati-fard, and M. Farmanbar, “Phononic thermal conductivity in silicene: the role of vacancy defects and boundary scattering,” Journal of Physics: Condensed Matter. 2017. link Times cited: 11 Abstract: We calculate the thermal conductivity of free-standing silic… read moreAbstract: We calculate the thermal conductivity of free-standing silicene using the phonon Boltzmann transport equation within the relaxation time approximation. In this calculation, we investigate the effects of sample size and different scattering mechanisms such as phonon–phonon, phonon-boundary, phonon-isotope and phonon-vacancy defect. We obtain some similar results to earlier works using a different model and provide a more detailed analysis of the phonon conduction behavior and various mode contributions. We show that the dominant contribution to the thermal conductivity of silicene, which originates from the in-plane acoustic branches, is about 70% at room temperature and this contribution becomes larger by considering vacancy defects. Our results indicate that while the thermal conductivity of silicene is significantly suppressed by the vacancy defects, the effect of isotopes on the phononic transport is small. Our calculations demonstrate that by removing only one of every 400 silicon atoms, a substantial reduction of about 58% in thermal conductivity is achieved. Furthermore, we find that the phonon-boundary scattering is important in defectless and small-size silicene samples, especially at low temperatures. read less NOT USED (high confidence) I. Sergio, M. Pruneda, L. Colombo, and P. O. Rontomé, “Thermal and transport properties of pristine single-layer hexagonal boron nitride : a first principles investigation,” Physical Review Materials. 2017. link Times cited: 12 Abstract: Molecular dynamics is used in combination with density funct… read moreAbstract: Molecular dynamics is used in combination with density functional theory to determine the thermal transport properties of the single-layer hexagonal boron nitride (SL h-BN) from ab initio calculations. Within this approach, the possible anisotropy in the thermal conductivity of SL h-BN was studied. For samples with finite length (of the order of 20 nm), we find a significant dependence of the conductivity on the transport direction. We make a direct comparison of the results obtained for two-dimensional (2D) layers and for nanoribbons with similar size, and show that, as a consequence of edge scattering, the ribbon geometry induces a significant decrease in the conductivity, and produces a strong change in the anisotropy. For the zigzag and armchair transport directions, the dependence of the thermal conductivity on the system length was also obtained, as well as its value in the 2D bulk limit case. A very small anisotropy was found for the limit of long samples, in contrast with the finite length ones. This is explained analyzing the dependence of the average square group velocities on the transport direction and the phonon frequency. read less NOT USED (high confidence) M. Cherukara, B. Narayanan, H. Chan, and S. Sankaranarayanan, “Silicene growth through island migration and coalescence.,” Nanoscale. 2017. link Times cited: 9 Abstract: We perform massively-parallel classical molecular dynamics (… read moreAbstract: We perform massively-parallel classical molecular dynamics (MD) simulations to study the long timescale monolayer silicene growth on an Ir (111) surface. We observe an intricate multi-stage growth process driven by atomic and cluster migration on the surface. Initial growth involves formation of sub-nanometer clusters via adatom surface diffusion. Subsequently, these clusters rearrange spontaneously with each additional Si atom, forming clusters containing 4-7 member rings. Growth of each cluster through adatom adhesion is accompanied by the formation of larger islands through cluster migration and coalescence. Coalescence of smaller, more mobile islands into larger clusters is aided by the internal rearrangement of rings within each cluster. This flexibility, both of clusters and their constituent atoms, allows the impinging clusters to reorient after first contact and form a more perfect union. We also report on the effect of temperature and flux on the growth process and the final nanostructure. Our study provides atomistic insights into the early stage growth mechanisms of silicene which can be significant for controlled synthesis of its 2D monolayers. read less NOT USED (high confidence) Q. Wang, X. Wang, R. Guo, and B. Huang, “Parametrization of Density Functional Tight-Binding Method for Thermal Transport in Bulk and Low-Dimensional Si Systems,” Journal of Physical Chemistry C. 2017. link Times cited: 6 Abstract: Understanding the thermal transport in different Si-based ma… read moreAbstract: Understanding the thermal transport in different Si-based materials is of both practical and academic importance because of the essential role of such materials in modern electronic and microelectromechanical applications and other areas. Conventional atomic modeling approaches such as density functional theory offer high accuracy but can hardly handle a large system, whereas the empirical potentials used in classical molecular dynamics often lack accuracy or transferability. We have thus developed a new parametrization of the Si–Si interaction of the density-functional-based tight-binding method for the atomic-scale investigation of thermal transport properties in various Si systems. We found that this parametrization can accurately predict many harmonic and anharmonic thermal transport properties in different silicon systems such as single-crystalline silicon, silicene, and silicene nanoribbons, showing excellent computational efficiency and transferability. Therefore, this Si–Si parameter set can contr... read less NOT USED (high confidence) T. Rakib, S. Saha, M. Motalab, S. Mojumder, and M. M. Islam, “Atomistic Representation of Anomalies in the Failure Behaviour of Nanocrystalline Silicene,” Scientific Reports. 2017. link Times cited: 29 NOT USED (high confidence) J. Pérez-Taborda, O. Caballero‐Calero, and MarisolMartín‐González, “Silicon‐Germanium (SiGe) Nanostructures for Thermoelectric Devices: Recent Advances and New Approaches to High Thermoelectric Efficiency.” 2017. link Times cited: 19 Abstract: Silicon and germanium present distinct and interesting trans… read moreAbstract: Silicon and germanium present distinct and interesting transport properties. However, composites made of silicon‐germanium (SiGe) have resulted in a breakthrough in terms of their transport properties. Currently, these alloys are used in different applications, such as microelectronic devices and integrated circuits, photovoltaic cells, and thermo‐ electric applications. With respect to thermoelectricity, in the last decades, Si 0.8 Ge 0.2 has attracted significant attention as an energy harvesting material, for powering space appli ‐ cations and other industrial applications. This chapter focuses on the recent advances and new approaches in silicon‐germanium (Si 1 − x Ge x ) nanostructures for thermoelectric devices with high thermoelectric efficiency obtained through magnetron sputtering. been proven to be useful in improving thermoelectric performance is to reduce dimensionality. Here, different configurations that the silicon‐germanium has been fabricated at the nanometric scale to improve its thermoelectric properties are shown. read less NOT USED (high confidence) H. Wang, G. Qin, G. Li, Q. Wang, and M. Hu, “Low thermal conductivity of monolayer ZnO and its anomalous temperature dependence.,” Physical chemistry chemical physics : PCCP. 2017. link Times cited: 44 Abstract: Two-dimensional (2D) materials have attracted tremendous int… read moreAbstract: Two-dimensional (2D) materials have attracted tremendous interest due to their fascinating physical and chemical properties and promising applications in nano-electronics, where thermal transport plays a vital role in determining the performance of devices. In this paper, we present a first-principles study of the thermal transport properties of monolayer zinc oxide (ZnO), which has potential applications in nano-electronics and thermoelectrics. The thermal conductivity of monolayer ZnO is found to be as low as 4.5 W m-1 K-1 at 300 K, which is dramatically lower than those of bulk ZnO and lots of other 2D materials. A detailed analysis is performed in the framework of Boltzmann transport theory and electronic structure to understand low thermal conductivity. Most surprisingly, the thermal conductivity of monolayer ZnO slowly decreases with temperature and does not follow the conventional 1/T law. This unusual phonon transport behavior arises from the dominant contribution of optical phonon modes to the overall thermal transport in monolayer ZnO, which has been rarely reported in the literature, and the significantly increased specific heat of the high frequency (optical) phonon modes with increasing temperature, both of which compensate the decrease in the phonon relaxation time. Our study highlights the abnormal thermal transport properties of the new 2D material and we anticipate that this research will motivate the experimentalists to further study other physical and chemical properties of monolayer ZnO for its emerging applications in thermoelectrics, thermal circuits, and nano-/opto-electronics. read less NOT USED (high confidence) J.-W. Jiang and Y.-P. Zhou, “Parameterization of Stillinger-Weber Potential for Two- Dimensional Atomic Crystals,” arXiv: Materials Science. 2017. link Times cited: 51 Abstract: We parametrize the Stillinger-Weber potential for 156 two-di… read moreAbstract: We parametrize the Stillinger-Weber potential for 156 two-dimensional atomic crystals. Parameters for the Stillinger-Weber potential are obtained from the valence force field model following the analytic approach (Nanotechnology 26, 315706 (2015)), in which the valence force constants are determined by the phonon spectrum. The Stillinger-Weber potential is an efficient nonlinear interaction, and is applicable for numerical simulations of nonlinear physical or mechanical processes. The supplemental resources for all simulations in the present work are available online in Ref. 1, including a fortran code to generate crystals' structures, files for molecular dynamics simulations using LAMMPS, files for phonon calculations with the Stillinger-Weber potential using GULP, and files for phonon calculations with the valence force field model using GULP. read less NOT USED (high confidence) C. Shao, X. Yu, N. Yang, Y. Yue, and H. Bao, “A Review of Thermal Transport in Low-Dimensional Materials Under External Perturbation: Effect of Strain, Substrate, and Clustering,” Nanoscale and Microscale Thermophysical Engineering. 2017. link Times cited: 36 Abstract: ABSTRACT Due to their exceptional electrical, thermal, and o… read moreAbstract: ABSTRACT Due to their exceptional electrical, thermal, and optical properties, low-dimensional (LD) materials are very promising for many applications, such as nanoelectronic devices, energy storage, energy conversion, and thermal management. The thermal performance of LD materials is often an important consideration in these applications. Although freestanding LD materials exhibit interesting thermal properties, they are almost never used in such a form. Instead, they are often integrated into a certain environment; for example, in a composite material or on a substrate. Due to the large surface-to-volume ratio of LD materials, the environment usually has a strong impact on the thermal transport properties of these materials. The thermal behavior of the LD materials can be completely different from the freestanding form. The effect of environmental perturbation on thermal transport properties has recently attracted a lot of research interest. In this article, we aim to provide a comprehensive review of how the typical external perturbations, including tensile strain, substrate, and clustering, can affect the thermal transport properties of LD materials. Emphasis will be placed on how these perturbations affect the lattice structure, phonon dispersion, lattice anharmonicity, and thermal conductivity. We will also summarize the achievements and the remaining challenges on this research topic. read less NOT USED (high confidence) B. Smith et al., “Temperature and Thickness Dependences of the Anisotropic In‐Plane Thermal Conductivity of Black Phosphorus,” Advanced Materials. 2017. link Times cited: 96 Abstract: The anisotropic basal-plane thermal conductivities of thin b… read moreAbstract: The anisotropic basal-plane thermal conductivities of thin black phosphorus obtained from a new four-probe measurement exhibit much higher peak values at low temperatures than previous reports. First principles calculations reveal the important role of crystal defects and weak thickness dependence that is opposite to the case of graphene and graphite due to the absence of reflection symmetry in puckered phosphorene. read less NOT USED (high confidence) R. Pablo-Pedro, H. Lopez-Rios, S. Fomine, and M. Dresselhaus, “Detection of Multiconfigurational States of Hydrogen-Passivated Silicene Nanoclusters.,” The journal of physical chemistry letters. 2017. link Times cited: 5 Abstract: Utilizing density functional theory (DFT) and a complete act… read moreAbstract: Utilizing density functional theory (DFT) and a complete active space self-consistent field (CASSCF) approach,we study the electronic properties of rectangular silicene nano clusters with hydrogen passivated edges denoted by H-SiNCs (nz,na), with nz and na representing the zigzag and armchair directions, respectively. The results show that in the nz direction, the H-SiNCs prefer to be in a singlet (S = 0) ground state for nz > na. However, a transition from a singlet (S = 0) to a triplet (S = 1) ground state is revealed for na > nz. Through the calculated Raman spectrum, the S = 0 and S = 1 ground states can be observed by the E2g (G) and A (D) Raman modes. Furthermore, H-SiNC clusters are shown to have HOMO-LUMO (HL) energy gaps, which decrease as a function of na and nz for S = 0 and S = 1 states. The H-SiNC with a S = 1 ground state can be potentially used for silicene-based spintronic devices. read less NOT USED (high confidence) N. Cortés, L. Rosales, L. Chico, M. Pacheco, and P. Orellana, “Enhancement of thermoelectric efficiency by quantum interference effects in trilayer silicene flakes,” Journal of Physics: Condensed Matter. 2017. link Times cited: 4 Abstract: In recent years, the enhancement of thermoelectric efficienc… read moreAbstract: In recent years, the enhancement of thermoelectric efficiencies has been accomplished in nanoscale systems by making use of quantum effects. We exploit the presence of quantum interference phenomena such as bound states in the continuum and Fano antiresonances in trilayer silicene flakes to produce sharp changes in the electronic transmission of the system. By applying symmetric gate voltages the thermoelectric properties can be tuned and, for particular flake lengths, a great enhancement of the figure of merit can be achieved. We show that the most favorable configurations are those in which the electronic transmission is dominated by the coupling of bound states to the continuum, tuned by an external gate. read less NOT USED (high confidence) A. Ramiere, S. Volz, and J. Amrit, “Heat flux induced blueshift of dominant phonon wavelength and its impact on thermal conductivity,” AIP Advances. 2017. link Times cited: 4 Abstract: The concept of dominant phonon wavelength is investigated in… read moreAbstract: The concept of dominant phonon wavelength is investigated in systems submitted to a heat flux at low temperatures. Using spectral energy distributions, a treatment of two-dimensional and three-dimensional structures is conducted in parallel. We demonstrate a significant reduction of the dominant phonon wavelength, up to 62%, due to a displacement of the phonon spectrum towards higher frequencies in presence of a heat flux. We name this phenomenon blueshift effect. A formula is provided to directly calculate the corrected dominant phonon wavelength. We illustrate the impact of the blueshift effect by showing that a temperature gradient of 10% at 4K yields a 20% reduction in the thermal conductivity. Therefore, ignoring the blueshift effect in a thermal model can notably alter the physical interpretation of measurements. The results suggest that an appropriate heat flux environment can improve thermoelectric device performances. read less NOT USED (high confidence) Z. Zhang, Y.-R. Yang, H. Fu, and R. Wu, “Design of spin-Seebeck diode with spin semiconductors,” Nanotechnology. 2016. link Times cited: 19 Abstract: We report a new design of spin-Seebeck diode using two-dimen… read moreAbstract: We report a new design of spin-Seebeck diode using two-dimensional spin semiconductors such as sawtooth-like (ST) silicence nanoribbons (SiNRs), to generate unidirectional spin currents with a temperature gradient. ST SiNRs have subbands with opposite spins across the Fermi level and hence the flow of thermally excited carriers may produce a net spin current but not charge current. Moreover, we found that even-width ST SiNRs display a remarkable negative differential thermoelectric resistance due to a charge–current compensation mechanism. In contrast, odd-width ST SiNRs manifest features of a thermoelectric diode and can be used to produce both charge and spin currents with temperature gradient. These findings can be extended to other spin semiconductors and open the door for designs of new materials and spin caloritronic devices. read less NOT USED (high confidence) X. Zhang, X. Gong, Y. Zhou, and M. Hu, “Tailoring thermal conductivity of AlN films by periodically aligned surface nano-grooves,” Applied Physics Letters. 2016. link Times cited: 4 Abstract: Low thermal conductivity in condensed matter is critical to … read moreAbstract: Low thermal conductivity in condensed matter is critical to a diverse range of technologies, such as high efficient thermoelectrics and thermal insulation. It is thus important to fabricate, grow, or assemble structures that can reach a low limit. For III-nitride with high intrinsic thermal conductivity, how to utilize periodic nanostructures to manipulate phonons and achieve controllable low thermal conductivity is rarely studied. Recently, periodically self-organized arrays of nano-grooves on AlN (0001) surface have been observed experimentally. Inspired by this, we perform non-equilibrium molecular dynamics simulations to explore the thermal transport in such structures. The dependence of thermal conductivity on the periodic length of the nano-grooves and the angle of the side wall is systematically studied. Remarkably, results show that the thermal conductivity has a minimum value for a critical periodic length, which is one order of magnitude lower than the counterpart bulk value. The intrinsic high ... read less NOT USED (high confidence) X. Xu, J. Chen, and B. Li, “Phonon thermal conduction in novel 2D materials,” Journal of Physics: Condensed Matter. 2016. link Times cited: 92 Abstract: Recently, there has been increasing interest in phonon therm… read moreAbstract: Recently, there has been increasing interest in phonon thermal transport in low-dimensional materials, due to the crucial importance of dissipating and managing heat in micro- and nano-electronic devices. Significant progress has been achieved for one-dimensional (1D) systems, both theoretically and experimentally. However, the study of heat conduction in two-dimensional (2D) systems is still in its infancy due to the limited availability of 2D materials and the technical challenges of fabricating suspended samples that are suitable for thermal measurements. In this review, we outline different experimental techniques and theoretical approaches for phonon thermal transport in 2D materials, discuss the problems and challenges of phonon thermal transport measurements and provide a comparison between existing experimental data. Special attention will be given to the effects of size, dimensionality, anisotropy and mode contributions in novel 2D systems, including graphene, boron nitride, MoS2, black phosphorous and silicene. read less NOT USED (high confidence) G. Qin and M. Hu, “Diverse Thermal Transport Properties of Two-Dimensional Materials: A Comparative Review.” 2016. link Times cited: 7 Abstract: The discovery of graphene led to an upsurge in exploring two… read moreAbstract: The discovery of graphene led to an upsurge in exploring two-dimensional (2D) materials, such as silicene, germanene, phosphorene, hexagonal boron nitride ( h -BN), and transition metal dichalcogenides (TMDCs), which have attracted tremendous attention due to their unique dimension-dependent properties in the applications of nanoelectronics, optoelectronics, and thermoelectrics. The phonon transport proper‐ ties governing the heat energy transfer have become a crucial issue for continuing progress in the electronic industry. This chapter reviews the state-of-the-art theoreti‐ cal and experimental investigations of phonon transport properties of broad 2D nanostructures in various forms, with graphene, silicene and phosphorene as repre‐ sentatives, all of which consist of single element. Special attention is given to the effect of different physical factors, such as sample size, strain, and layer thickness. The effect of substrate and the phonon transport properties in heterostructures are also dis‐ cussed. We find that the phonon transport properties of 2D materials largely depend on their atomic structure and interatomic bonding nature, showing a diverse intrinsic phonon behavior and disparate response to external environment. read less NOT USED (high confidence) Y. Liu, Y. Feng, Z. Huang, and X. Zhang, “Thermal Conductivity of 3D Boron-Based Covalent Organic Frameworks from Molecular Dynamics Simulations,” Journal of Physical Chemistry C. 2016. link Times cited: 13 Abstract: Covalent organic frameworks (COFs) have been widely investig… read moreAbstract: Covalent organic frameworks (COFs) have been widely investigated for use in gas storage and separation, while their thermal properties have been scarcely studied. In the study reported in this paper, the thermal conductivities of 3D boron-based COFs were investigated for the first time using molecular dynamics simulations (MD) employing the Green–Kubo method. The predicted thermal conductivities of COF-102, COF-103, COF-105, and COF-108 were on the order of 0.1 W/(m·K) at 300 K. The thermal conductivity decreased by up to 47% with the increase in temperature from 200 to 500 K. This resulting low thermal conductivity was due to the short mean free path of the phonon in the COFs, which was deduced to be 2.7–9.2 nm. The low-frequency phonon modes below 50 THz contributed mostly to heat conduction. By analyzing the phonon vibrational density of states and overlap energy between per two bonded atoms, it was revealed that the connection between phenylene rings in COF-102 and COF-103 weakens the phonon coupling ... read less NOT USED (high confidence) E. Voyiatzis and M. Böhm, “Atomic and global mechanical properties of systems described by the Stillinger–Weber potential,” Journal of Physics: Condensed Matter. 2016. link Times cited: 0 Abstract: Analytical expressions for the stress and elasticity tensors… read moreAbstract: Analytical expressions for the stress and elasticity tensors of materials, in which the interactions are described by the Stillinger–Weber potential, are derived in the context of the stress fluctuation formalism. The derived formulas can be used both in Monte Carlo and molecular dynamics simulations. As an example of possible applications, they are employed to calculate the influence of the temperature and system size on the mechanical properties of crystalline cubic boron nitride. The system has been studied by molecular dynamics simulations. The computed mechanical properties are in good agreement with available experimental data and first principle calculations. In the studied crystalline cubic boron nitride system, the employed formalism is of higher accuracy than the ‘small-strain’ non-equilibrium method. The dominant contributions to the elastic constants stem from the Born and stress fluctuation terms. An increase in the system size reduces the statistical uncertainties in the computation of the mechanical properties. A rise of the temperature leads to a slight increase in the observed uncertainties. The derived expressions for the stress and elasticity tensors are further decomposed into sums of atomic level stress and atomic level elasticity tensors. The developed factorization enables us (i) to quantify the contribution of the various chemical groups, in the case under consideration of the different atoms, to the observed mechanical properties and (ii) to determine the elastic constants with reduced computational uncertainties. The reason is that the exact values of some terms of the proposed factorization can be determined theoretically beforehand. Thus, they can be substituted in the derived formulas leading to an enhanced convergence. read less NOT USED (high confidence) L. Pereira, B. Mortazavi, M. Makaremi, and T. Rabczuk, “Anisotropic thermal conductivity and mechanical properties of phagraphene: a molecular dynamics study,” RSC Advances. 2016. link Times cited: 62 Abstract: Phagraphene is a novel 2D carbon allotrope with interesting … read moreAbstract: Phagraphene is a novel 2D carbon allotrope with interesting electronic properties which has been recently theoretically proposed. Phagraphene is similar to a defective graphene structure with an arrangement of pentagonal, heptagonal and hexagonal rings. In this study we investigate the thermal conductivity and mechanical properties of phagraphene using molecular dynamics simulations. Using the non-equilibrium molecular dynamics method, we found the thermal conductivity of phagraphene to be anisotropic, with room temperature values of 218 ± 20 W m−1 K−1 along the armchair direction and 285 ± 29 W m−1 K−1 along the zigzag direction. Both values are one order of magnitude smaller than for pristine graphene. The analysis of the phonon group velocities also shows a significant reduction in this quantity for phagraphene in comparison to graphene. By performing uniaxial tensile simulations, we studied the deformation process and mechanical response of phagraphene. We found that phagraphene exhibits a remarkable high tensile strength around 85 ± 2 GPa, whereas its elastic modulus is also anisotropic along the in-plane directions, with values of 870 ± 15 GPa and 800 ± 14 GPa for the armchair and zigzag directions, respectively. The lower thermal conductivity of phagraphene along with its predicted electronic properties suggests that it could be a better candidate than graphene in future carbon-based thermoelectric devices. read less NOT USED (high confidence) R. Su, Z. Yuan, J. Wang, and Z. Zheng, “Predicting the phonon spectra of coupled nonlinear chains using effective phonon theory,” Journal of Physics A: Mathematical and Theoretical. 2016. link Times cited: 2 Abstract: In general one-dimensional nonlinear lattices, extensive stu… read moreAbstract: In general one-dimensional nonlinear lattices, extensive studies have discovered the existence of renormalized phonons due to nonlinear interactions and found these renormalized phonons, as the energy carriers, are responsible for heat transport. Within the framework of renormalized phonons, a generic form of renormalized phonon spectrum has been derived and effective phonon theory (EPT) has been developed to explain the heat transport in general 1D nonlinear lattices. Our attention is dedicated to generalizing the EPT for two-layer nonlinear lattices and deriving the analytic expression of phonon spectra. By calculating the phonon spectra of different coupled models with EPT, it is found that the phonon dispersion relation is in good agreement with the result obtained from the spectral energy density method. It is demonstrated that the EPT of a coupled system can predict the phonon spectra of two-layer nonlinear lattices well. Thus, this finding may shed light on the prediction of heat conduction behavior in a coupled system, qualitatively, and provide a useful guide for designing thermal devices. read less NOT USED (high confidence) S. Srinivasan, U. Ray, and G. Balasubramanian, “Thermal conductivity reduction in analogous 2D nanomaterials with isotope substitution: Graphene and silicene,” Chemical Physics Letters. 2016. link Times cited: 12 NOT USED (high confidence) C. Chen, Y. She, H. Xiao, J.-wen Ding, J. Cao, and Z. X. Guo, “Enhancing the ballistic thermal transport of silicene through smooth interface coupling,” Journal of Physics: Condensed Matter. 2016. link Times cited: 5 Abstract: We have performed nonequilibrium molecular dynamics calculat… read moreAbstract: We have performed nonequilibrium molecular dynamics calculations on the length (L ?>) dependence of thermal conductivity (K ?>) of silicene both supported on and sandwiched between the smooth surfaces, i.e. h-BN, at room temperature. We find that K ?> of silicene follows a power law K∝Lβ ?>, with β ?> increasing from about 0.3–0.4 under the effect of interface coupling, showing an enhancement of the ballistic thermal transport of silicene. We also find that β ?> can be further increased to about 0.6 by increasing the interface coupling strength for the silicene sandwiched between h-BN. The increase of β ?> for the supported case is found to come from the variation of the flexural acoustic (ZA) phonon mode and the first optical phonon mode induced by the substrate, whereas the unusual increase of β ?> for the sandwiched case is attributed to the increment of velocities of all three acoustic phonon modes. These findings provide an interesting route for manipulating the ballistic energy flow in nanomaterials. read less NOT USED (high confidence) G. Qin et al., “Diverse anisotropy of phonon transport in two-dimensional group IV-VI compounds: A comparative study.,” Nanoscale. 2016. link Times cited: 180 Abstract: New classes of two-dimensional (2D) materials beyond graphen… read moreAbstract: New classes of two-dimensional (2D) materials beyond graphene, including layered and non-layered, and their heterostructures, are currently attracting increasing interest due to their promising applications in nanoelectronics, optoelectronics and clean energy, where thermal transport is a fundamental physical parameter. In this paper, we systematically investigated the phonon transport properties of the 2D orthorhombic group IV-VI compounds of GeS, GeSe, SnS and SnSe by solving the Boltzmann transport equation (BTE) based on first-principles calculations. Despite their similar puckered (hinge-like) structure along the armchair direction as phosphorene, the four monolayer compounds possess diverse anisotropic properties in many aspects, such as phonon group velocity, Young's modulus and lattice thermal conductivity (κ), etc. Especially, the κ along the zigzag and armchair directions of monolayer GeS shows the strongest anisotropy while monolayer SnS and SnSe show almost isotropy in phonon transport. The origin of the diverse anisotropy is fully studied and the underlying mechanism is discussed in details. With limited size, the κ could be effectively lowered, and the anisotropy could be effectively modulated by nanostructuring, which would extend the applications to nanoscale thermoelectrics and thermal management. Our study offers fundamental understanding of the anisotropic phonon transport properties of 2D materials, and would be of significance for further study, modulation and applications in emerging technologies. read less NOT USED (high confidence) Y. Yue, J. Zhang, X. Tang, S. Xu, and X. Wang, “Thermal transport across atomic-layer material interfaces,” Nanotechnology Reviews. 2015. link Times cited: 31 Abstract: Emergence of two-dimensional (2D) materials with atomic-laye… read moreAbstract: Emergence of two-dimensional (2D) materials with atomic-layer structures, such as graphene and MoS2, which have excellent physical properties, provides the opportunity of substituting silicon-based micro/nanoelectronics. An important issue before large-scale applications is the heat dissipation performance of these materials, especially when they are supported on a substrate, as in most scenarios. Thermal transport across the atomic-layer interface is essential to the heat dissipation of 2D materials due to the extremely large contact area with the substrate, when compared with their atomic-scale cross-sections. Therefore, the understanding of the interfacial thermal transport is important, but the characterization is very challenging due to the limitations for temperature/thermal probing of these atomic-layer structures. In this review, widely used characterization techniques for experimental characterization as well as their results are presented. Emphasis is placed on the Raman-based technology for nm and sub-nm temperature differential characterization. Then, we present physical understanding through theoretical analysis and molecular dynamics. A few representative works about the molecular dynamics studies, including our studies on the size effect and rectification phenomenon of the graphene-Si interfaces are presented. Challenges as well as opportunities in the thermal transport study of atomic-layer structures are discussed. Though many works have been reported, there is still much room in both the development of experimental techniques as well as atomic-scale simulations for a clearer understanding of the physical fundamentals of thermal transport across the atomic-layer interfaces, considering the remarkable complexity of physical/chemical conditions at the interface. read less NOT USED (high confidence) L. Cui, Y. Feng, and X. Zhang, “Enhancement of heat conduction in carbon nanotubes filled with fullerene molecules.,” Physical chemistry chemical physics : PCCP. 2015. link Times cited: 18 Abstract: Heat conduction in carbon nanopeapods (CNPs), i.e. carbon na… read moreAbstract: Heat conduction in carbon nanopeapods (CNPs), i.e. carbon nanotubes (CNTs) filled with fullerene C60 molecules, is investigated using molecular dynamics simulations. The enhancement mechanisms of CNP thermal conductivity, compared with bare CNTs, are discussed via the local heat flux onto a single atom, the relative contributions of different phonon oscillation frequencies to thermal conductivity and the phonon vibrational density of states. The result shows that filled C60 can increase the CNT thermal conductivity by up to 9.6 times in the temperature range of 100-500 K. The constructive phonon mode couplings between the tube and C60 in a frequency range of 0-20 THz, especially in x-, y-direction transverse acoustic modes and the radial breath mode, are primarily responsible for the increment of thermal conductivity. In addition, filled C60 molecules in CNPs enhance the mass transfer contribution to the total heat flux. This contribution accounts for 22-58% in CNPs, much higher than 12% in CNTs. With the temperature going up, the phonon scattering increases and the contribution from mass transfer to total heat flux decreases. Therefore, the CNP thermal conductivity decreases with rising temperature. This study sheds lights on nanoscale thermal/phonon engineering by utilization of CNTs and C60. read less NOT USED (high confidence) X. Gu and R. Yang, “Phonon transport and thermal conductivity in two-dimensional materials,” arXiv: Materials Science. 2015. link Times cited: 50 Abstract: Two-dimensional materials, such as graphene, boron nitride a… read moreAbstract: Two-dimensional materials, such as graphene, boron nitride and transition metal dichalcogenides, have attracted increased interest due to their potential applications in electronics and optoelectronics. Thermal transport in two-dimensional materials could be quite different from three-dimensional bulk materials. This article reviews the progress on experimental measurements and theoretical modeling of phonon transport and thermal conductivity in two-dimensional materials. We focus our review on a few typical two-dimensional materials, including graphene, boron nitride, silicene, transition metal dichalcogenides, and black phosphorus. The effects of different physical factors, such as sample size, strain and defects, on thermal transport in Two-dimensional materials are summarized. We also discuss the environmental effect on the thermal transport of two-dimensional materials, such as substrate and when two-dimensional materials are presented in heterostructures and intercalated with inorganic components or organic molecules. read less NOT USED (high confidence) Y. Guo and M. Wang, “Phonon hydrodynamics and its applications in nanoscale heat transport,” Physics Reports. 2015. link Times cited: 176 NOT USED (high confidence) W.-T. Xu, L. Zhu, Y. Cai, G. Zhang, and B. Li, “Direction dependent thermal conductivity of monolayer phosphorene: parameterization of Stillinger-Weber potential and molecular dynamics study,” arXiv: Mesoscale and Nanoscale Physics. 2015. link Times cited: 70 Abstract: A Stillinger-Weber interatomic potential is parameterized fo… read moreAbstract: A Stillinger-Weber interatomic potential is parameterized for phosphorene. It well reproduces the crystal structure, cohesive energy and phonon dispersion predicted by first-principles calculations. The thermal conductivity of phosphorene is further explored by equilibrium molecular dynamics simulations adopting the optimal set of potential parameters. At room temperature, the intrinsic thermal conductivities along zigzag and armchair directions are about 152.7 and 33.0 W/mK, respectively, with a large anisotropy ratio of five. The remarkably directional dependence of thermal conductivity in phosphorene, consistent with previous reports, is mainly due to the strong anisotropy of phonon group velocities, and weak anisotropy of phonon lifetimes as revealed by lattice dynamics calculations. Moreover, the effective phonon mean free paths at zigzag and armchair directions are about 141.4 and 43.4nm, respectively. read less NOT USED (high confidence) L.-chuan Zhang et al., “Tinselenidene: a Two-dimensional Auxetic Material with Ultralow Lattice Thermal Conductivity and Ultrahigh Hole Mobility,” Scientific Reports. 2015. link Times cited: 144 NOT USED (high confidence) H. Sadeghi, S. Sangtarash, and C. Lambert, “Enhanced Thermoelectric Efficiency of Porous Silicene Nanoribbons,” Scientific Reports. 2015. link Times cited: 82 NOT USED (high confidence) X. Zhang, H. Bao, and M. Hu, “Bilateral substrate effect on the thermal conductivity of two-dimensional silicon.,” Nanoscale. 2015. link Times cited: 66 Abstract: Silicene, the silicon-based counterpart of graphene, has rec… read moreAbstract: Silicene, the silicon-based counterpart of graphene, has received exceptional attention from a wide community of scientists and engineers in addition to graphene, due to its unique and fascinating physical and chemical properties. Recently, the thermal transport of the atomic thin Si layer, critical to various applications in nanoelectronics, has been studied; however, to date, the substrate effect has not been investigated. In this paper, we present our nonequilibrium molecular dynamics studies on the phonon transport of silicene supported on different substrates. A counter-intuitive phenomenon, in which the thermal conductivity of silicene can be either enhanced or suppressed by changing the surface crystal plane of the substrate, has been observed. This phenomenon is fundamentally different from the general understanding of supported graphene, a representative two-dimensional material, in which the substrate always has a negative effect on the phonon transport of graphene. By performing phonon polarization and spectral energy density analysis, we explain the underlying physics of the new phenomenon in terms of the different impacts on the dominant phonons in the thermal transport of silicene induced by the substrate: the dramatic increase in the thermal conductivity of silicene supported on the 6H-SiC substrate is due to the augmented lifetime of the majority of the acoustic phonons, while the significant decrease in the thermal conductivity of silicene supported on the 3C-SiC substrate results from the reduction in the lifetime of almost the entire phonon spectrum. Our results suggest that, by choosing different substrates, the thermal conductivity of silicene can be largely tuned, which paves the way for manipulating the thermal transport properties of silicene for future emerging applications. read less NOT USED (high confidence) S. Balendhran, S. Walia, H. Nili, S. Sriram, and M. Bhaskaran, “Elemental analogues of graphene: silicene, germanene, stanene, and phosphorene.,” Small. 2015. link Times cited: 702 Abstract: The fascinating electronic and optoelectronic properties of … read moreAbstract: The fascinating electronic and optoelectronic properties of free-standing graphene has led to the exploration of alternative two-dimensional materials that can be easily integrated with current generation of electronic technologies. In contrast to 2D oxide and dichalcogenides, elemental 2D analogues of graphene, which include monolayer silicon (silicene), are fast emerging as promising alternatives, with predictions of high degree of integration with existing technologies. This article reviews this emerging class of 2D elemental materials - silicene, germanene, stanene, and phosphorene--with emphasis on fundamental properties and synthesis techniques. The need for further investigations to establish controlled synthesis techniques and the viability of such elemental 2D materials is highlighted. Future prospects harnessing the ability to manipulate the electronic structure of these materials for nano- and opto-electronic applications are identified. read less NOT USED (high confidence) L. Pierantoni et al., “Advanced techniques for the band structure-quantum transport modeling in graphene and 2D-materials beyond graphene,” 14th IEEE International Conference on Nanotechnology. 2014. link Times cited: 0 Abstract: We report on advanced full-wave techniques, both in the freq… read moreAbstract: We report on advanced full-wave techniques, both in the frequency and energy domains, aimed at the investigation of the combined electromagnetic-coherent transport problem in pristine graphene, as well as in some 2D-materials beyond graphene, with particular attention to buckleld silicene. read less NOT USED (high confidence) L. Pierantoni et al., “Full-wave techniques for the electromagnetic-quantum transport modeling in nano-devices,” 2014 International Semiconductor Conference (CAS). 2014. link Times cited: 1 Abstract: We report on multiphysics full-wave techniques in the freque… read moreAbstract: We report on multiphysics full-wave techniques in the frequency (energy)-domain and time-domain, aimed at the investigation of the combined electromagnetic-coherent transport problem in nano-structured materials and devices, in particular carbon-based materials/devices. The quantum transport is modeled by i) discrete Hamiltonians at atomistic scale, ii) Schrödinger equation, and/or Dirac/Dirac-like eqs. at continuous level. In the frequency-domain, a rigorous Poisson-coherent transport equation system is provided. In the time-domain, Maxwell equations are self-consistently coupled to the Schrödinger/Dirac equations. read less NOT USED (high confidence) V. V. Hoang and H. T. C. Mi, “Free-standing silicene obtained by cooling from 2D liquid Si: structure and thermodynamic properties,” Journal of Physics D: Applied Physics. 2014. link Times cited: 20 Abstract: The structure and various thermodynamic properties of free-s… read moreAbstract: The structure and various thermodynamic properties of free-standing silicene have been studied by computer simulation. Models are obtained by cooling from buckling two-dimensional (2D) liquid Si via molecular dynamics (MD) simulation with Stillinger–Weber interatomic potential. The temperature dependence of total energy, heat capacity, mean ring size and mean coordination number shows that silicenization of 2D liquid Si exhibits a first-order-like behavior. The evolution of radial distribution function upon cooling from the melt also shows that solidification occurs in the system. The final configuration of silicene is analyzed via coordination, bond-angle, interatomic distance and ring distributions or distribution of buckling in the system. 2D visualization of atomic configurations clearly demonstrated that silicene obtained ‘naturally’ by cooling from the melt exhibits various structural previously unreported behaviors. We find the formation of polycrystalline silicene with clear grain boundaries containing various defects including various vacancies, Stone–Wales defects or skew rings and multimembered rings unlike those proposed in the literature. However, atoms in the obtained silicene are mostly involved in six-fold rings, forming a buckling honeycomb structure like that found in practice. We find that buckling is not unique for all atoms in the models although the majority of atoms reveal buckling of the most stable low-buckling silicene found in the literature. The buckling distribution is broad and symmetric. Our comprehensive MD simulation of a relatively large silicene model containing 104 atoms and obtained ‘naturally’ by cooling from the melt provides original insights into the structure and thermodynamics of this important 2D material. read less NOT USED (high confidence) X. Gu and R. Yang, “First-principles prediction of phononic thermal conductivity of silicene: A comparison with graphene,” Journal of Applied Physics. 2014. link Times cited: 199 Abstract: There has been great interest in two-dimensional materials, … read moreAbstract: There has been great interest in two-dimensional materials, beyond graphene, for both fundamental sciences and technological applications. Silicene, a silicon counterpart of graphene, has been shown to possess some better electronic properties than graphene. However, its thermal transport properties have not been fully studied. In this paper, we apply the first-principles-based phonon Boltzmann transport equation to investigate the thermal conductivity of silicene as well as the phonon scattering mechanisms. Although both graphene and silicene are two-dimensional crystals with similar crystal structure, we find that phonon transport in silicene is quite different from that in graphene. The thermal conductivity of silicene shows a logarithmic increase with respect to the sample size due to the small scattering rates of acoustic in-plane phonon modes, while that of graphene is finite. Detailed analysis of phonon scattering channels shows that the linear dispersion of the acoustic out-of-plane (ZA) phonon modes, which is induced by the buckled structure, makes the long-wavelength longitudinal acoustic phonon modes in silicene not as efficiently scattered as that in graphene. Compared with graphene, where most of the heat is carried by the acoustic out-of-plane (ZA) phonon modes, the ZA phonon modes in silicene only have ∼10% contribution to the total thermal conductivity, which can also be attributed to the buckled structure. This systematic comparison of phonon transport and thermal conductivity of silicene and graphene using the first-principle-based calculations shed some light on other two-dimensional materials, such as two-dimensional transition metal dichalcogenides. read less NOT USED (high confidence) S. Aghaei, “Electronic and Magnetic Properties of Two-dimensional Nanomaterials beyond Graphene and Their Gas Sensing Applications: Silicene, Germanene, and Boron Carbide.” 2017. link Times cited: 1 NOT USED (definite) G. Qin, H. Wang, Z. Qin, and M. Hu, “Activated Lone-Pair Electrons Lead to Low Lattice Thermal Conductivity: A Case Study of Boron Arsenide,” Transport. 2019. link Times cited: 2 Abstract: Reducing thermal conductivity ($\kappa$) is an efficient way… read moreAbstract: Reducing thermal conductivity ($\kappa$) is an efficient way to boost the thermoelectric performance to achieve direct solid-state conversion to electrical power from thermal energy, which has lots of valuable applications in reusing waste resources. In this study, we propose an effective approach for realizing low $\kappa$ by introducing lone-pair electrons or making the lone-pair electrons stereochemically active through bond nanodesigning. As a case study, by cutting at the (111) cross section of the three-dimensional cubic boron arsenide (c-BAs), the $\kappa$ is lowered by more than one order of magnitude in the resultant two-dimensional system of graphene-like BAs (g-BAs) due to the stereochemically activated lone-pair electrons. Similar concept can be also extended to other systems with lone-pair electrons beyond BAs, such as group III-V compounds, where a strong correlation between $\kappa$ modulation and electronegativity difference for binary compounds is found. Thus, the lone-pair electrons combined with a small electronegativity difference could be the indicator of lowering $\kappa$ through bond nanodesigning to change the coordination environment. The proposed approach for realizing low $\kappa$ and the underlying mechanism uncovered in this study would largely benefit the design of thermoelectric devices with improved performance, especially in future researches involving novel materials for energy applications. read less NOT USED (definite) M. Khalkhali, F. Khoeini, and A. Rajabpour, “Thermal transport in silicene nanotubes: Effects of length, grain boundary and strain,” International Journal of Heat and Mass Transfer. 2019. link Times cited: 20 |
SW_ZhangXieHu_2014OptimizedSW1_Si__MO_800412945727_005
