Anharmonic effects on lattice dynamics and thermal transport of two-dimensional InTe monolayer

Abstract

The lattice thermal conductivity (κl) plays a key role in the performance of thermoelectric (TE) materials, where the lower values lead to higher figure of merit values. Two-dimensional (2D) group III-VI monolayers such as InTe are promising materials for TE energy generation owing to their low κl that lead to high TE figure of merit values. In this work, we investigate the influence of the lattice anharmonicity on the lattice thermal conductivity of InTe monolayer. The thermodynamic parameters are calculated by using the self-consistent phonon (SCP) theory. The κl value of the InTe monolayer is obtained to be 0.30 Wm−1 K−1 by using the standard Boltzmann transport equation (BTE) approach, while it is 3.58 Wm−1 K−1 by using SCP + BTE approach. These results confirm the importance of the anharmonic effects on the κl value, where it was found to be significantly higher (91%) using the SCP + BTE approach than that obtained using the standard BTE approach.