Alloying to increase the band gap for improving thermoelectric properties of Ag2Te

Abstract

Ag₂Te simultaneously shows high mobility and low thermal conductivity, however the relatively low band gap of ∼0.2 eV prevents it from achieving high thermoelectric figure of merit, zT, in the high temperature phase. In this study, the band gap of Ag₂Te has been increased enabling a zT of unity by forming alloys and composites with PbTe, thereby demonstrating the importance of exploiting potentially good thermoelectrics among these small band gap semiconductors and similar materials.