Low temperature study of the structural, electronic and thermoelectric behaviors of PbS lead chalcogenide

Abstract

This paper aims to investigate the structural, electronic and thermoelectric properties of lead sulfide using the first principles calculations. The exchange-correlation potential is treated by two approximations, the local density approximation (LDA) and the generalized gradient approximation (GGA) to calculate the structural and electronic properties. The thermoelectric properties of PbS sample are well predicted by the exchange-correlation potential GGA. The calculated band structure, the density of states (DOS) and electron density shows that lead sulfide is a semiconductor with gap energy of 0.082 and 0.47eV. Finally, temperature dependent thermoelectric properties like electrical and thermal conductivity, Seebeck coefficient and power factor were calculated in detail by employing the Boltzmann transport theory under the BoltzTraP code. The PbS compound has a large power factor at high temperature with a positive Seebeck coefficient which indicates that lead sulfide is p-type semiconductor, and major carrier is predominated by holes. Therefore, it reveals that PbS can be used as promising materials for high potential thermoelectri