Drastic increase in thermoelectric power factor of mixed Sb2Te3-In2Te3 thin films

Abstract

Thermoelectric power factor is an indicator of the performance of a thermoelectric material. Attempts have been made by various techniques, like doping, to improve the thermoelectric conversion efficiency of materials. In the present study, a layer structured thermoelectric material Sb2Te3 is alloyed to In2Te3 using vacuum deposition method at 423 K to significantly enhance the power factor of ?118 ?Wm-1K?2 (at 450 K). Structurally, all films were polycrystalline in nature as clearly reflected in XRD patterns. All films were showing p-type conductivity, and electrical conductivity of In2Te3 films increased with increasing Sb2Te3 content. The seebeck coefficient is found to be higher for un-doped In2Te3 than that of Sb2Te3-In2Te3 and pure Sb2Te3 films. However, the thermoelectric power factor of 25% Sb2Te3 alloyed In2Te3 films is enhanced by 11.9 times that of In2Te3 films and 4 times that of Sb2Te3 films at 320 K. It is interesting to note that efficiency of the mixed films is higher than that of the individual films. 2019 Elsevier Ltd