SnSe: Kx intermetallic thermoelectric polycrystals prepared by arc-melting
Neutron powder diffraction and thermoelectric characterization of SnSe:Kx intermetallic alloys are presented. Nanostructured ingots were prepared by arc-melting elemental tin and selenium along with potassium hydride. Up to x = 0.1 of K can be incorporated into SnSe. Rietveld refinement of the diffr...
| Autores: | , , , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2022 |
| País: | España |
| Institución: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/91198 |
| Acceso en línea: | https://hdl.handle.net/20.500.14352/91198 |
| Access Level: | acceso abierto |
| Palabra clave: | 538.9 Low thermal conductivity Transport properties Skutterudites Electron Impact Charge Merit PBTE Física de materiales 2211 Física del Estado Sólido |
| Sumario: | Neutron powder diffraction and thermoelectric characterization of SnSe:Kx intermetallic alloys are presented. Nanostructured ingots were prepared by arc-melting elemental tin and selenium along with potassium hydride. Up to x = 0.1 of K can be incorporated into SnSe. Rietveld refinement of the diffractograms locates potassium on the Sn site in the high-temperature Cmcm structure. However, in the low-temperature Pnma structure, K cannot be localized by difference Fourier maps, indicating the incorporation of K in a disordered form in the interlayer space. STEM-EELS indicates the incorporation of K into the SnSe grains. The resistivity upon K-doping at intermediate temperatures decreases by 1–2 orders of magnitude, but at high temperature is higher than the undoped SnSe. The Seebeck coefficient of K-doped SnSe remains p-type and almost temperature independent (400 μV/K for x = 0.1). The ultralow thermal conductivity of undoped SnSe decreases further upon K-doping to below 0.3 W/m K. |
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