Rapid characterization of thermoelectric properties of composition spread (La_(1-x)Ca_x)VO_3 films

摘要

Vanadium oxides possess various interesting properties due to multivalence of a vanadium atom and attract our interest as a target material for the exploration of new applications. We investigated vanadates (La_(1-x)Ca_x)VO_3 with a perovskite structure as thermoelectric (TE) materials because heavy electrons in vanadates are expected to generate large thermopower. To proceed the investigation of thermoelectric properties of the composition spread library more efficiently, we devised a new instrument of multi-channel measurement of their thermoelectric properties. The polarity of Seebeck coefficients changed from positive (0 ≤ x ≤ 0.2) to negative (0.2 ≤ x ≤ 1.0), and the composition where the film shows the highest power factor in our investigated range is around pure LaVO_3 (x ≈ 0).