Thermal transport properties of monolayer MoSe2 with defects
Two-dimensional (2D) molybdenum diselenide (MoSe2) as one of the ultrathin transition metal dichalcogenides (TMDs) has attracted considerable attention because of its potential applications in thermoelectric and nano-electronic devices. Here, the thermal conductivity of monolayer MoSe2 and its responses on simulated size and environmental temperature are studied by nonequilibrium molecular dynamics simulations. With the increase of sample length, the thermal conductivity of monolayer MoSe2 nanoribbons exhibits an enhancement whereas it is insensitive to the width. At room temperature, the thermal conductivities of monolayer MoSe2 along armchair and zigzag directions are 17.758 and 18.932 W/(m·K), respectively, which are consistent with previous results from first-principles. The impact of defects on thermal conductivity has also been studied by varying the concentration of vacancy from 0.1% to 0.5%. The results show that increase of the defect concentration will greatly suppress the thermal conductivity. The 0.5% defect concentration with Mo vacancy can result in a thermal conductivity reduction of ~43%. Such study would provide a good insight on the tunable thermal transport for potential application of not only monolayer MoSe2, but also many other TMDs.