On the microscopic view of the low thermal conductivity of buckling two-dimensional materials from molecular dynamics

Abstract

Thermal transport properties of two-dimensional (2D) materials have been extensively investigated. However, the microscopic view from the atomic motion is lacking. In this paper, the thermal transport in buckling 2D Germanene, Arsenene, and Antimonene are studied based on molecular dynamics (MD) simulations with systematical comparison to graphene. It was found that the thermal conductivity of the buckling structures is 20 ∼ 60 times lower than that of graphene due to the softened phonon modes in the buckling structures. Besides, the phonon modes with frequency in 0 ∼ 5 THz are contributing to the discrepancy in the overall thermal conductivity among buckling structures.