Janus Al2STe monolayer: A prospective thermoelectric material

Abstract Two dimensional materials based on chalcogenides are showing exciting thermoelectric efficiency. Recent experimental synthesisation of several Janus monolayers inspire investigation of novel materials. In this paper, we study the thermoelectric performance of the novel Janus Al2STe monolayer using Density Functional theory. We found that Janus Al2STe monolayer is an indirect band gap semiconductor with an energy gap of 1.17 eV and is dynamically stable. The transport coefficients such as Seebeck coefficient, electrical conductivity, power factor, and electronic thermal conductivity are evaluated using BoltzTraP2 code based on Boltzmann transport theory within constant relaxation time approximation. The dependence of relaxation time on temperature has been approximated with the deformation potential theory. Further, the lattice component of thermal conductivity has been obtained using ShengBTE code. The calculated value of ZT shows that both n-type and p-type Janus monolayer have outstanding thermoelectric performance. From the evaluated results, we conclude that Janus Al2STe monolayer can be used as a propitious candidate in the fabrication of thermoelectric devices.