Improvement in thermoelectric properties of CuAlO2 by adding Fe2O3

Fe addition up to x = 0.1 in CuAl1−xFexO2 (0 ≤ x ≤ 0.2) led to an increase in electrical conductivity with an increase in Fe content because of increases in the grain size, density, and carrier density. On the other hand, Fe substitution up to x = 0.1 caused a decrease in the Seebeck coefficient due mainly to an increase in carrier density. The highest value of power factor (1.1 × 10−4 W m−1 K−2) was attained for CuAl0.9Fe0.1O2 at 1140 K. We have demonstrated in the present study that Fe addition is highly effective for enhancing high-temperature thermoelectric properties of CuAlO2.