Thermal transport and thermoelectric properties of transition metal dichalcogenides Mo$X_2$ from first-principles calculation

TL;DR

This study uses first-principles calculations to analyze the thermal and thermoelectric properties of MoX2 monolayers, revealing MoTe2's high thermoelectric efficiency and potential for energy conversion applications.

Contribution

It provides a comprehensive theoretical analysis of MoX2 monolayers' thermoelectric properties using advanced computational models, highlighting MoTe2's superior performance.

Findings

MoTe2 has the highest ZT of 2.77 at 550 K.

MoX2 monolayers exhibit promising thermoelectric properties.

Low thermal conductivity and high electrical conductivity contribute to high ZT.

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 Mo$X_2$ ($X$ = 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 MoTe$_2$ has the highest ZT of 2.77 among the other Mo$X_2$ at 550 K due to its low thermal conductivity and high electrical conductivity. Consequently, we suggest that Mo$X_2$ 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.