Thermoelectric Properties of Multinary-doped ZnO

Abstract

Changes in the thermoelectric properties of multinary-doped ZnO were investigated particularly focusing on the thermal conductivity. Binary doping of ZnO with Al and Cu significantly reduced the thermal conductivity of the oxide, whereas the electrical conductivity was strongly deteriorated. Formation of CuAl2O4 spinel phase was suggested to be responsible for both enhanced phonon scattering and reduced carrier concentration. Ternary doping of ZnO with Al, Cu, and Ga resulted in high dimensionless figure-of-merit of ZT = 0.58 at 1238 K due to the reduced thermal conductivity and improved electrical conductivity.