Thermal transport and thermoelectric properties of transition metal dichalcogenides MoX 2 from first-principles calculation

Abstract

The properties of two-dimensional (2D) materials have been extensively studied and applied in various applications. Our interest is to theoretically investigate the thermal transport and thermoelectric properties of the 2D transition metal dichalcogenides MoX 2 (X=S, Se, Te). We employ density functional theory and Boltzmann transport theory with relaxation-time approximation to calculate the electronic and transport properties. We also implemented the kinetic-collective model to improve the calculation of lattice thermal conductivity. Our calculations indicate that MoTe2 has the highest ZT of 2.77 among the other MoX 2 at 550 K due to its low thermal conductivity and high electrical conductivity. Consequently, we suggest that MoX 2 monolayers hold promise as materials for energy conversion devices due to their relatively high ZT. Moreover, these results could be beneficial to design 2D material-based high-performance thermoelectric devices.