The thermoelectric properties of Ba3 Co2 O 6 (CO3)0.7 have been investigated using prismatic single crystals elongated along the c axis. Ba3 Co 2 O6 (CO3)0.7 has a pseudo-one-dimensional structure similar to that of 2H perovskite-type BaCoO3 and contains CoO6 octahedral columns running parallel to the c axis. The prismatic crystals are grown by a flux method using a K2 CO3 - BaCl2 flux. The electrical conductivity (σ) along the columns (c axis) exhibits a metallic behavior (670-320 S cm-1 in the temperature range of 300-1100 K), whereas the temperature dependence of the electrical conductivity perpendicular to the c axis is semiconducting. The Seebeck coefficient (S) along the columns is positive and greater than 100 μV K-1 over the measured temperature range (116-128 μV K-1). Ba3 Co2 O6 (CO 3) 0.7 shows power factors (σ S2) of 5.5× 10-4 -9.0× 10-4 W m-1 K -2 above room temperature, relatively high values for an oxide material.
ASJC Scopus subject areas
- Physics and Astronomy(all)