Substantial thermal conductivity reduction in mischmetal skutterudites Mm_xCo_4Sb_12 prepared under high-pressure conditions, due to uneven distribution of the rare-earth elements
Thermoelectric mischmetal-filled Mm(x)Co(4)Sb(12) (Mm: natural cocktail of rare-earth elements, mostly Ce and La) skutterudites have been synthesized and sintered in one step under high-pressure conditions at 3.5 GPa in a piston-cylinder hydrostatic press. Synchrotron X-ray diffraction patterns disp...
| Autores: | , , , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2019 |
| País: | España |
| Institución: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/104550 |
| Acceso en línea: | https://hdl.handle.net/20.500.14352/104550 |
| Access Level: | acceso abierto |
| Palabra clave: | 538.9 546 Thermoelectric performance Física de materiales Química inorgánica (Química) 2211 Física del Estado Sólido 2303 Química Inorgánica |
| Sumario: | Thermoelectric mischmetal-filled Mm(x)Co(4)Sb(12) (Mm: natural cocktail of rare-earth elements, mostly Ce and La) skutterudites have been synthesized and sintered in one step under high-pressure conditions at 3.5 GPa in a piston-cylinder hydrostatic press. Synchrotron X-ray diffraction patterns display a splitting of the diffraction peaks ascribed to purely Ce-, and Mm-filled skutterudite phases, which have been analyzed and confirmed by high-resolution TEM and EELS. A total thermal conductivity () of 1.51 W m(-1) K-1 is measured at 773 K for Mm(0.5)Co(4)Sb(12), below that of other filled skutterudites, which is promoted by the enhanced phonon scattering over a broad range of the phonon spectrum due to the inhomogeneous and nanoscale mischmetal inclusion. Compared to undoped CoSb3 skutterudite synthesized by conventional methods, is reduced by a factor of 3, while the power factor is also substantially enhanced. |
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