The authors report measurements of the electrical resistivity, Seebeck coefficient, and thermal conductivity for a series of misfit-layered oxides Ca3 Co4-x Fex O9+δ (x=0, 0.05, 0.1, 0.15, 0.2) prepared by solid state reaction. Structural parameters are refined with superspace group of X2m (0b0) s0 using powder x-ray diffraction data. With partial substitution of Fe+2 for Co+3, the resistivity decreases, while the thermopower increases simultaneously. The x=0.05 sample exhibits a higher figure of merit (Z=3.01× 10-4 K-1) than that of Ca3 Co4 O9+δ (0.33× 10-4 K-1) at 300 K, indicating much improvement of thermoelectric characteristics via partial substitution of Fe for Co.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)