Thermoelectric properties of BiPbCuSeO oxyselenides.

In this work, BiPbCu SeO ( = 0, 0.02, 0.06, and 0.08) compounds were synthesized by a solid state reaction followed by spark plasma sintering. The effect of simultaneous Bi to Pb substitution and Cu vacancy introduction on thermoelectric properties was investigated systematically. The power factor was significantly enhanced, contributing to the increase in the value. As a result, the of 0.75 at 773 K was obtained for the BiPbCuSeO sample. To reveal the factors constraining the of BiPbCuSeO-based oxyselenides, a further careful analysis of literature data was performed. We highlighted that for Pb-doped oxyselenides, the power factor is almost independent of the synthesis technique, while the lattice thermal conductivity is the main property determining and is highly affected by the synthesis method.