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

TL;DR

This paper investigates how grain boundaries in polycrystalline MoS2 affect thermal transport, using a multiscale modeling approach combining molecular dynamics and finite element analysis to provide insights into 2D material heat conduction.

Contribution

It introduces a multiscale modeling framework to quantify thermal conductivity in polycrystalline TMDs, specifically MoS2, considering grain boundary effects.

Findings

Grain boundaries significantly influence thermal transport in MoS2.

The multiscale approach accurately predicts thermal conductivity.

Insights applicable to other 2D materials and structures.

Abstract

Transition metal dichalcogenides (TMDs) represent a large family of high-quality 2D materials with attractive electronic, thermal, chemical, and mechanical properties. Chemical vapour 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 modelling. Insight provided by this investigation can be useful to evaluate the effective thermal transport along a wide variety of 2D materials and structures.