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arXiv · 1409.2189

Enhancement of thermoelectric properties by Se substitution in layered bismuth-chalcogenide LaOBiS2-xSex

Yoshikazu Mizuguchi·Atsushi Omachi·Yosuke Goto·Yoichi Kamihara·Masanori Matoba·Takafumi Hiroi·Joe Kajitani·Osuke Miura
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Abstract

We have investigated the thermoelectric properties of the novel layered bismuth chalcogenides LaOBiS2-xSex. The partial substitution of S by Se produced the enhancement of electrical conductivity (metallic characteristics) in LaOBiS2-xSex. The power factor largely increased with increasing Se concentration. The highest power factor was 4.5 uW/cmK2 at around 470 deg. C for LaOBiS1.2Se0.8. The obtained dimensionless figure-of-merit (ZT) was 0.17 at around 470 deg. C in LaOBiS1.2Se0.8.

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Yoshikazu Mizuguchi, Atsushi Omachi, Yosuke Goto, Yoichi Kamihara, Masanori Matoba, Takafumi Hiroi, Joe Kajitani, Osuke Miura. 2014-09-12. Enhancement of thermoelectric properties by Se substitution in layered bismuth-chalcogenide LaOBiS2-xSex. https://doi.org/10.1063/1.4900953

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