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arXiv · 1903.11801

Enhanced thermoelectricity by controlled local structure in bismuth-chalcogenides

K. Terashima·Y. Yano·E. Paris·Y. Goto·Y. Mizuguchi·Y. Kamihara·T. Wakita·Y. Muraoka·N. L. Saini·T. Yokoya
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Abstract

Spectroscopic techniques, including photoelectron spectroscopy, diffuse reflectance, and x-ray absorption, are used to investigate the electronic structure and the local structure of LaOBiS$_{2-x}$Se$_x$ thermoelectric material. It is found that Se substitution effectively suppresses local distortion, that can be responsible for the increased carrier mobility together with a change in the electronic structure. The results suggest a possible way to control thermoelectric properties by tuning of the local crystal structure of these materials.

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K. Terashima, Y. Yano, E. Paris, Y. Goto, Y. Mizuguchi, Y. Kamihara, T. Wakita, Y. Muraoka, N. L. Saini, T. Yokoya. 2019-03-28. Enhanced thermoelectricity by controlled local structure in bismuth-chalcogenides. https://doi.org/10.1063/1.5087096

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