Figure of Merit of (Sb0.75Bi0.25)(2-x) In (x) Te2.8Se0.2 Single Crystals

Abstract

We have shown previously that indium doping is beneficial for thermoelectric properties of (Sb0.75Bi0.25)(2)Te-3. This effect was ascribed to a change in the magnitude and mechanism of hole scattering and a decrease in thermal conductivity. Since the state-of-the-art material for p-type legs in low-temperature applications is the quaternary Bi0.5Sb1.5Te3-y Se (y) , we have attempted to dope this material with In, hoping to improve its properties further. Indeed, the doping enhances the figure of merit of (Sb0.75Bi0.25)(2-x) In (x) Te2.8Se0.2 by more than 15% compared with the values measured on undoped (Sb0.75Bi0.25)(2)Te2.8Se0.2 below room temperature.