Phonon thermal properties of graphene from molecular dynamics using different potentials

Abstract

Phonon thermal transport in graphene has attracted significant interest in recent years. Phonon thermal properties of graphene are investigated by molecular dynamics simulations using the Tersoff, Tersoff-2010, REBO, and AIREBO potentials. By calculating the phonon properties and thermal conductivity of graphene, the performance of the potentials is evaluated based on comparisons with experimental data. It shows that the Tersoff-2010 and REBO display better dispersion curves for graphene than the original Tersoff and AIREBO. The Tersoff-2010 correctly provides the Γ point phonon velocities of the LA and TA branches as well as the G peak frequency with a value of 46 THz. In addition, the acoustic phonon relaxation time derived from the Tersoff-2010 satisfies the ideal relation "τ ∝ ν." It is also found that the Tersoff-2010 provides the highest graphene thermal conductivity among the used potentials, and estimates about 30.0% contribution for flexural phonons to the total thermal conductivity. By comparison, the Tersoff-2010 potential is demonstrated to be the most suitable one to describe the phonon thermal properties of graphene.

Heat transport in two-dimensional materials by directly solving the phonon Boltzmann equation under Callaway's dual relaxation model

“…Once the discrete deviational phonon intensities are resolved, the temperature distribution and heat flux distribution can be calculated through a discretization of Eqs. (14) and (15), respectively:…”

“…The theoretical work mainly consists of two groups: molecular dynamics (MD) simulation and phonon Boltzmann equation modeling. MD simulation is often flawed by the insufficient treatment of quantum effects [14], diverse atomic interaction potential functions [15], and relatively small simulation cells. In contrast, phonon Boltzmann equation modeling is a mesoscopic approach avoiding or relieving the aforementioned three drawbacks [16,17].…”

Enhanced thermal transport across multilayer graphene and water by interlayer functionalization

“…The optimized Tersoff potential, 28,29 which may accurately display the phonon dispersion of graphene, is adopted to describe the C-C covalent interactions. 29,30 The extended simple point charge (SPC/E) model 31 is used to represent the interactions between water molecules. Carbon-water bonding and the interlayer coupling in MLG are van der Waals type, modeled by the Lennard-Jones…”

Phonon thermal properties of graphene on h-BN from molecular dynamics simulations

“…The optimized Tersoff potential 22 is adopted for C-C interactions, which gives a sound description of phonon dispersion and group velocities for graphene. 23 The Tersoff potential developed by Sevik et al 15 is used to model atomic interactions in h-BN. The interlayer interactions are described as the van der Waals type using the Lennard-Jones potentials,…”