Oxide-ion thermopower of acceptor-doped perovskites: The impact of inter-defect interactions

The effect of inter-defect interaction on the hopping thermopower α in acceptor-doped oxides is considered on the example of wide-gap AIIBIV1–xRIIIxO3–δ perovskites with oxide-ion charge carriers. It is shown that acceptor-bound states of defects and inter-carrier correlations essentially affect α and its dependence on dopant content and temperature even at low doping level. The method of determining the correct charge carriers concentration and heat of transport from thermopower data for such systems is discussed. The presented results can also be useful for understanding thermoelectric phenomena caused by other types of hopping charge carriers in various acceptor-doped oxides promising for electrochemical applications.