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arXiv · 2006.12747

Phonon Scattering Mechanism in Thermoelectric Materials Revised via Resonant X-ray Dynamical Diffraction

Adriana Valério·Rafaela F. S. Penacchio·Maurício B. Estradiote·Marli R. Cantarino·Fernando A. Garcia·Sérgio L. Morelhão·Niamh Rafter·Stefan W. Kycia·Guilherme A. Calligaris·Cláudio M. R. Remédios
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Abstract

Engineering of thermoelectric materials requires an understanding of thermal conduction by lattice and electronic degrees of freedom. Filled skutterudites denote a large family of materials suitable for thermoelectric applications where reduced lattice thermal conduction attributed to localized low-frequency vibrations (rattling) of filler cations inside large cages of the structure. In this work, a multi-wavelength method of exploiting X-ray dynamical diffraction in single crystals of CeFe$_4$P$_{12}$ is presented and applied to resolve the atomic amplitudes of vibrations. The results suggest that the vibrational dynamics of the whole filler-cage system is the actual active mechanism behind the optimization of thermoelectric properties.

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Adriana Valério, Rafaela F. S. Penacchio, Maurício B. Estradiote, Marli R. Cantarino, Fernando A. Garcia, Sérgio L. Morelhão, Niamh Rafter, Stefan W. Kycia, Guilherme A. Calligaris, Cláudio M. R. Remédios. 2020-06-23. Phonon Scattering Mechanism in Thermoelectric Materials Revised via Resonant X-ray Dynamical Diffraction. https://doi.org/10.1557/mrc.2020.37

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