The thermal conductivity of van der Waals hexagonal boron nitride/graphene heterostructure: A combined equilibrium molecular dynamics (EMD) and density functional theory (DFT) study

Abstract

Two-dimensional van der Waals (vdW) heterostructures are critical for advancing nanoscale thermal management in next-generation electronics. Hexagonal boron nitride (h-BN) and graphene, with their structural similarity and minimal lattice mismatch (1.8%), offer unique advantages as hybrid heat-spreading materials. This study investigates the thermal conductivity of single-layer h-BN/graphene (SLh-BN/SLG) heterostructures using equilibrium molecular dynamics (EMD) simulations based on the Green−Kubo method, evaluating both in-plane and out-of-plane phonon transport. Density functional theory (DFT) calculations elucidate phonon dispersion relations and interfacial interactions, revealing the critical role of low-frequency acoustic phonon modes in governing thermal transport. Results demonstrate that the SLh-BN/SLG heterostructure achieves a thermal conductivity of 1631.9 ± 26.8 Wm^–1K^–1 in the AA stacking configuration—surpassing the AB stacking configurations. This enhancement is attributed to synergistic phonon coupling at the interface, which minimizes scattering losses. The findings highlight the potential of h-BN/graphene heterostructures for efficient heat dissipation in nanoelectronics, providing a foundation for designing devices with precise thermal control.