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Enhanced Thermoelectric Performance of c-Axis-Oriented Epitaxial Ba-Doped BiCuSeO Thin Films.

ABSTRACT: We reported the epitaxial growth of c-axis-oriented Bi1-xBaxCuSeO (0?? x ??10%) thin films and investigated the effect of Ba doping on the structure, valence state of elements, and thermoelectric properties of the films. X-ray photoelectron spectroscopy analysis reveal that Bi3+ is partially reduced to the lower valence state after Ba doping, while Cu and Se ions still exist as +?1 and -?2 valence state, respectively. As the Ba doping content increases, both resistivity and Seebeck coefficient decrease because of the increased hole carrier concentration. A large power factor, as high as 1.24 mWm-1 K-2 at 673 K, has been achieved in the 7.5% Ba-doped BiCuSeO thin film, which is 1.5 times higher than those reported for the corresponding bulk samples. Considering that the nanoscale-thick Ba-doped films should have a very low thermal conductivity, high ZT can be expected in the films.

SUBMITTER: Yuan D

PROVIDER: S-EPMC6261905 | biostudies-other | 2018 Nov

REPOSITORIES: biostudies-other

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Enhanced Thermoelectric Performance of c-Axis-Oriented Epitaxial Ba-Doped BiCuSeO Thin Films.

Yuan Dachao D Guo Shuang S Hou Shuaihang S Ma Yuejin Y Wang Jianglong J Wang Shufang S

Nanoscale research letters 20181128 1

We reported the epitaxial growth of c-axis-oriented Bi1-xBaxCuSeO (0 ≤ x ≤ 10%) thin films and investigated the effect of Ba doping on the structure, valence state of elements, and thermoelectric properties of the films. X-ray photoelectron spectroscopy analysis reveal that Bi3+ is partially reduced to the lower valence state after Ba doping, while Cu and Se ions still exist as + 1 and - 2 valence state, respectively. As the Ba doping content increases, both resi ...[more]

PMID: 30488129

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