title: Remarkable enhancement in thermoelectric performance of BiCuSeO by Cu deficiencies.
abstract: A significant enhancement of thermoelectric performance in layered oxyselenides BiCuSeO was achieved. The electrical conductivity and Seebeck coefficient of BiCu(1-x)SeO (x = 0-0.1) indicate that the carriers were introduced in the (Cu(2)Se(2))(2-) layer by Cu deficiencies. The maximum of electrical conductivity is 3 × 10(3) S m(-1) for Bicu(0.975)Seo 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 BiCu(0.975)SeO by introducing Cu deficiencies, which makes it a promising candidate for medium temperature thermoelectric applications.
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Li-Dong
authors.initials: LD
authors.lastname: Zhao
authors.forename: Yaochun
authors.initials: Y
authors.lastname: Liu
authors.forename: Jinle
authors.initials: J
authors.lastname: Lan
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Fu
authors.initials: F
authors.lastname: Li
authors.forename: Bo-Ping
authors.initials: BP
authors.lastname: Zhang
authors.forename: David
authors.initials: D
authors.lastname: Berardan
authors.forename: Nita
authors.initials: N
authors.lastname: Dragoe
authors.forename: Yuan-Hua
authors.initials: YH
authors.lastname: Lin
authors.forename: Ce-Wen
authors.initials: CW
authors.lastname: Nan
authors.forename: Jing-Feng
authors.initials: JF
authors.lastname: Li
authors.forename: Hongmin
authors.initials: H
authors.lastname: Zhu