Ca-doped RCoO3 (R = Gd, Sm, Nd, Pr) as thermoelectric materials

The electrical resistivity and Seebeck coefficient of (R0.9Ca0.1)CoO3 (R = Gd, Sm, Nd, Pr) rapidly decrease with increasing ionic radius of the rare-earth element, and the Seebeck coefficients (p-type) are fairly high at low temperatures and attain low and constant values at high temperatures; (Pr0.9Ca0.1)CoO3 shows the highest figure-of-merit, 1.3 x 10(-4) K-1 at 85 degrees C, although this rapidly decreases with temperature above 300 degrees C due to the decreasing Seebeck coefficient and increasing electronic thermal conductivity.