Potential thermoelectric performance of hole-doped Cu₂O

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 Cu₂O may be such a material. We find that hole-doped Cu₂O has a high thermopower of above 200 μV K^-1 even with doping levels as high as 5.2 × 10²⁰ cm^-3 at 500 K, mainly attributed to the heavy valence bands of Cu₂O. This is reminiscent of the cobaltate family of high-performance oxide thermoelectrics and implies that hole-doped Cu₂O could be an excellent thermoelectric material if suitably doped.