Thermoelectric properties of Ca_1-xY_xMnO₃ and Ca_0.9Y_0.1-yFe_yMnO₃ perovskite compounds

Polycrystalline Ca1-xYxMnO3 (x = 0.0; 0.1; 0.3; 0.5; 0.7) and Ca0.9Y0.1-yFeyMnO3 (y = 0.00; 0.01; 0.03; 0.05) compounds were prepared by solid-state reaction. X-ray diffraction (XRD) analysis revealed all XRD peaks of all the samples as identical to the orthorhombic structure. The thermoelectric properties of these compounds were investigated from 300 K to 1200 K.

It was found that the studied samples are n-type thermoelectric material with thepower factor (PF) of the undoped (x = 0.0) sample was 1.8 × 10-4 Wm1 K2 at about 1150 K and the PF of x = 0.1 sample was 1.0 × 10-4 Wm1 K2 in the temperature range of (300 K ÷ 850 K), it was higher than the PF of the x = 0.0 sample in the same temperature range.

With the system of Ca0.9Y0.1-yFey MnO3, the power factor of the y = 0.01 sample was 1.4× 10-4 Wm-1K-2 at 950 K, it was higher than that for the undoped sample CaMnO3 in the temperature range of (300 K ÷ 950 K).