Effects of mechanical milling on preparation and properties of CuAl1−xFexO2 thermoelectric ceramics

CuAl1−xFexO2 (x = 0, 0.1, and 0.2) thermoelectric ceramics produced by a reaction-sintering process were investigated. Pure CuAlO2 and CuAl0.9Fe0.1O2 were obtained. Minor CuAl2O4 phase formed in CuAl0.8Fe0.2O2. Addition of 10 mol% Fe lowered the sintering temperature obviously and enhanced the grain growth. At x = 0.1, electrical conductivity = 3.143 Ω−1 cm−1, Seebeck coefficient = 418 μV K−1, and power factor = 5.49 × 10−5 W m−1 K−2 at 600 °C were obtained. The reaction-sintering process is simple and effective in preparing CuAlO2 and CuAl0.9Fe0.1O2 thermoelectric ceramics for applications at high temperatures.