Improved stability and high thermoelectric performance through cation site doping in n-type La-doped Mg3Sb1.5Bi0.5

Abstract

n-Type conduction in a Mg₃Sb_1.5Bi_0.5 system is achieved with La-doping at cation sites with a peak zT > 1. La-doped samples exhibit much higher doping efficiency and dopability compared to other chalcogen-doped samples. This allows greater tunability of the electronic properties. La-doping also significantly improves the thermal stability of n-type Mg₃Sb_1.5Bi_0.5 measured via a long-term Hall carrier concentration measurement.