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arXiv · 1810.07344

Understanding Phonon Scattering by Nano-Precipitates in Potassium-Doped Lead Chalcogenides

Zhao Wang·Xiaolong Yang·Dan Feng·Haijun Wu·Jesus Carrete·Li-Dong Zhao·Chao Li·Shaodong Cheng·Biaolin Peng·Guang Yang·Jiaqing He
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Abstract

We present a comprehensive experimental and theoretical study of phonon scattering by nanoprecipitates in potassium-doped PbTe, PbSe and PbS. We highlight the role of the precipitate size distribution measured by microscopy, whose tuning allows for thermal conductivities lower than the limit achievable with a single size. The correlation between the size distribution and the contributions to thermal conductivity from phonons in different frequency ranges provides a physical basis to the experimentally measured thermal conductivities, and a criterion to estimate the lowest achievable thermal conductivity. The results have clear implications for efficiency enhancements in nanostructured bulk thermoelectrics.

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Zhao Wang, Xiaolong Yang, Dan Feng, Haijun Wu, Jesus Carrete, Li-Dong Zhao, Chao Li, Shaodong Cheng, Biaolin Peng, Guang Yang, Jiaqing He. 2018-10-17. Understanding Phonon Scattering by Nano-Precipitates in Potassium-Doped Lead Chalcogenides. https://doi.org/10.1021/acsami.6b14266

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