Stabilizing the Optimal Carrier Concentration in Al/Sb-Codoped GeTe for High Thermoelectric Performance.

GeTe is a promising thermoelectric material and has attracted growing research interest recently. In this study, the effect of Al doping and AlS thus, it has long been considered as an unfavorable dopant for the optimization of GeTe-based materials. However, when Al and Sb were codoped into GeTe, the hole concentration was effectively suppressed, and the lattice thermal conductivity can be reduced. Eventually, a maximum zT of ∼2.0 at 773 K was achieved in Al&Sb-codoped Al0.01Sb0.1Ge0.89Te.