A significant enhancement of thermoelectric performance in layered oxyselenides BiCuSeO was achieved. The electrical conductivity and Seebeck coefficient of BiCu1-xSeO (x = 0-0.1) indicate that the carriers were introduced in the (Cu2Se2)2- layer by Cu deficiencies. The maximum of electrical conductivity is 3 × 103 S m-1 for Bicu0.975Seo at 650 °C, much larger than 470 S m-1 for pristine BiCuSeO. Featured with very low thermal conductivity (∼0.5 W m-1 K-1) and a large Seebeck coefficient (+273 μV K-1), ZT at 650 °C is significantly increased from 0.50 for pristine BiCuSeO to 0.81 for BiCu0.975SeO by introducing Cu deficiencies, which makes it a promising candidate for medium temperature thermoelectric applications.
ASJC Scopus subject areas
- Colloid and Surface Chemistry