Thermal boundary conductance of two-dimensional MoS2 interfaces

Understanding the thermal properties of two-dimensional (2D) materials and devices is essential for thermal management of 2D applications. Here, we perform molecular dynamics simulations to evaluate the thermal boundary conductance (TBC) between one to five layers of MoS2 and amorphous SiO2 as well as between single-layer MoS2 and crystalline AlN. We also calculate the specific heat of MoS2. The results of all calculations are compared to existing experimental data. In general, the TBC of such 2D interfaces is low, below ∼20 MW m−2 K−1, due to the weak van der Waals (vdW) coupling and mismatch of phonon density of states (PDOS) between materials. However, the TBC increases with vdW coupling strength, with temperature, and with the number of MoS2 layers (which introduce additional phonon modes). These findings suggest that the TBC of 2D materials is tunable by modulating their interface interaction, the number of layers, and finding a PDOS-matched substrate, with important implications for future energy-efficient 2D electronics, photonics, and thermoelectrics.