High pressure effect on the electronic structure and thermoelectric properties of BiCuSeO: first-principles calculations

Abstract

The effects of high pressure on the electronic structure and thermoelectric properties of BiCuSeO have been investigated by using first-principles calculations and the semi-classical Boltzmann transport theory. The electronic band gap increases with increasing pressure, and the band structure near the Fermi level of BiCuSeO is modified by applying hydrostatic pressure. It is found that the electrical conductivity of BiCuSeO can be enhanced under pressure, and such dependence can be explained by the pressure-induced change of the electronic structure of BiCuSeO. Furthermore, the doping dependence of power factors of n- and p-type BiCuSeO at three different pressures are estimated, suggesting that n-type doping of this compound would be more favorable for improving the thermoelectric properties under external pressure.