Interfacial thermal conductance in graphene/MoS2 heterostructures.

Using non-equilibrium molecular dynamics simulations, we investigate the thermal transport in van der Waals heterostructures consisting of alternating multilayer graphene and multilayer MoS 2 . It is found that the thermal conductance at graphene/MoS 2 (G/M) interface is much lower than that at graphene/graphene (G/G) and MoS 2 /MoS 2 (M/M) interfaces. This low interfacial thermal conductance is attributed to the low friction at G/M interface, which significantly reduces the contribution of shearing modes to the thermal conductance. It is also found that there is no thermal rectification at the G/M interface as the thermal conductance is independent on the heat flux direction. Moreover, the interfacial thermal conductance can be effectively tuned by cross-plane strain. More specifically, a 5% tensile strain is able to reduce the interfacial thermal conductance by 70%; while a 5% compressive strain is able to increase the thermal conductance by 150%. Unexpectedly, the G/M interfacial thermal conductance is found to increase with increasing the defect density near the interface, which is in strong contrast to the in-plane thermal conductivity. This unexpected increase in thermal conductance can be explained by the enhanced phonon coupling at the G/M interface arising from the enhanced interface friction caused by the defects. [ABSTRACT FROM AUTHOR]