Structural, morphological and thermoelectric properties of copper deficient and excessive Cu2-xS nanoparticles with (x=0-0.3)

Abstract

Cu2-xS emerged as a potential thermoelectric material for use in various temperature ranges. The abundance, low price, the safety of its elements, and strong performance at relatively high temperatures are among its benefits. In this study, Cu2-xS (x= 0, 0.1, 0.2, and 0.3) nanoparticles are synthesized using a hydrothermal method. The effect of copper content on the structural and thermoelectric properties has been investigated. The copper atoms have changed the phase of the Cu2-xS crystal structure due to changes in the kinetic release rate of copper. The lower Seebeck coefficient and high electrical conductivity with increasing x value or decreasing copper concentration in the Cu2-xS matrix were observed. The copper vacancies created more charge carrier concentration. The maximum Seebeck coefficient value in the Cu2.0S sample is achieved by carrier localization. The Cu1.9S sample was found to have the best thermoelectric power generation performance, with a maximum power factor value of 1.72 × 10−3 Wm−1C−2.