High Temperature Thermoelectric Properties of Dy-doped CaMnO3 Ceramics

Dy-doped CaMnO3 ceramics have been synthesized by co-precipitation method combined with the solid-state reaction. Phase composition and microstructure analysis indicate that high density and pure CaMnO3 phase can be achieved. The electric conductivity can be enhanced by Dy doping, and result in a slight increase of the thermal conductivity. The highest dimensionless figure of merit ZT of 0.15 has been obtained at 973 K for x = 0.02 sample, which is about 4 times larger than that of the pure CaMnO3, which indicate that CaMnO3 can be a promising candidate for n-type thermoelectric material at high temperature.