Thermal transport across the CoSb3–graphene interface

Abstract

CoSb₃ shows intrinsically excellent electric transport performance but high thermal conductivity, resulting in low thermoelectric performance. The use of graphene to form heterogeneous interfaces shows great potential for significantly lessening the lattice thermal conductivity (κ_L) in CoSb₃-based composites. Molecular dynamics (MD) simulations are carried out in the present work to study the interfacial thermal conductance across the CoSb₃–graphene interface in the temperature range of 300 K to 800 K. The interfacial thermal conductance exhibits irregular fluctuations with temperature and CoSb₃ length. Furthermore, we explored the effect of graphene layers on the interfacial heat transport of the CoSb₃–graphene system. The results demonstrate that graphene layers affect the interfacial thermal conductance due to the suppression of heat flux in multilayer graphene across the c-axis. The phonon density of states (PDOS) of the CoSb₃–graphene system reveals a decreased low-frequency vibration mode at 0–7 THz and an enhanced high-frequency vibration mode compared with those of CoSb₃, indicating that thermal transport can be effectively suppressed by the addition of graphene.