  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 that hole doped Cu2O may be such a material. We
find that hole-doped Cu2O has a high thermopower of above 200 microV/K even
with doping levels as high as 5.5x10 20 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.
