Thermal conductivity of biaxial-strained MoS2: sensitive strain dependence and size-dependent reduction rate

Abstract

The effect of biaxial tensile strain on the thermal transport properties of MoS₂ is investigated by combining first-principles calculations and the Boltzmann transport equation. The thermal conductivities of single layer MoS₂ are found to be heavily suppressed by the applied strains; even a moderate biaxial tensile strain, 2 ~ 4%, could result in a 10 ~ 20% reduction in the thermal conductivity. Most interestingly, the reduction rate of thermal conductivity is size-dependent, which is due to different dominant phonon scattering mechanisms at different sizes of MoS₂ samples. The sensitive strain dependence of thermal conductivity indicates that strain engineering could be an effective method to enhance the figure of merit for thermoelectric applications of MoS₂.