Strong thermal transport along polycrystalline transition metal dichalcogenides revealed by multiscale modeling for MoS₂

Transition metal dichalcogenides (TMDs) represent a large family of high-quality 2D materials with attractive electronic, thermal, chemical and mechanical properties. Chemical vapor deposition (CVD) technique is currently the most reliable route to synthesis few-atomic layer thick and large-scale TMDs films. However, the effects of grain boundaries formed during the CVD method on the properties of TMDs nanomembranes have remained less explored. In this study, we therefore aim to investigate the thermal conduction along polycrystalline molybdenum disulfide (MoS₂) as the representative member of TMDs nanomembranes family. This goal was achieved by developing a combined atomistic-continuum multiscale method. In the proposed approach, reactive molecular dynamics simulations were carried out to assess thermal contact conductance of diverse grain boundaries with various defects configurations. The effective thermal conductivity along the CVD grown polycrystalline and single-layer MoS₂ was finally acquired by conducting finite element modeling. Insight provided by this investigation can be useful to evaluate the effective thermal transport along a wide variety of 2D materials and structures.