Multiscale modelling of heat conduction in all-MoS2 single-layer heterostructures

Abstract

Successful isolation of atom thick molybdenum disulfide (MoS₂) films has opened promising routes toward its practical applications in nanoelectronics. Recently, experimental fabrication of single-layer MoS₂ membranes made from semiconducting (2H) and metallic (1T) phases was successfully accomplished in order to reach advanced MoS₂ heterostructures with tunable electronic properties. A comprehensive understanding of the heat conduction properties of these heterostructures plays a crucial role not only for the overheating concerns in nanoelectronics but also for the design of specific systems such as thermoelectric nanodevices. In this investigation, we accordingly explore the thermal conductivity along all-MoS₂ heterostructures by developing a combined atomistic-continuum multiscale model. In this approach, molecular dynamics simulations were employed to compute the thermal conductivity of pristine 2H and 1T phases and also the thermal contact conductance between 1T and 2H phases. Properties obtained from the atomistic simulations were finally used to construct macroscopic samples of MoS₂ heterostructures using the finite element method. Our investigation confirms the possibility of finely tuning the heat transport along MoS₂ heterostructures by controlling the domain size and the concentration of different phases. Findings from our multiscale model provide useful insight regarding the thermal conduction response of all-MoS₂ heterostructures.