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arXiv · 2404.01311

Colossal Seebeck coefficient of thermoelectric material calculated by space charge effect, and phonon drag background

Hirofumi Kakemoto
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Abstract

Recently colossal Seebeck coefficient ($S$) has found in the several thermoelectric (TE) materials. We present colossal $S$ and large thermal electron motivate force (EMF) reproduced by space charge (SC) model, introducing multi-Debye lengths within grain boundaries (GBs) of TE materials with phonon drag (PD) effect accompanying with electron by electron-phonon interaction. In addition to $S$, the polarity reversal was also reproduced by transfer process with inner bias around SP generated from thermal EMF. Colossal $S$ and EMF for TE material were reproduced by inner SC model as a functions of averaged multi-Debye length within GBs.

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Hirofumi Kakemoto. 2024-03-09. Colossal Seebeck coefficient of thermoelectric material calculated by space charge effect, and phonon drag background. https://doi.org/10.1021/acsami.4c19044

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