Potential thermoelectric performance of hole-doped Cu2O

Abstract

High thermoelectric performance in oxides requires stable conductive materials that have suitable band structures. Here we show, based on an analysis of the thermopower and related properties using first-principles calculations and Boltzmann transport theory in the relaxation time approximation, that hole-doped Cu _2 O may be such a material. We find that hole-doped Cu _2 O has a high thermopower of above 200 μ V K ^−1 even with doping levels as high as 5.2 × 10 ^20 cm ^−3 at 500 K, mainly attributed to the heavy valence bands of Cu _2 O. This is reminiscent of the cobaltate family of high-performance oxide thermoelectrics and implies that hole-doped Cu _2 O could be an excellent thermoelectric material if suitably doped.