Enhanced figure of merit in nanostructured (Bi,Sb)2Te3 with optimized composition, prepared by a straightforward arc-melting procedure

Sb-doped Bi2Te3 is known since the 1950s as the best thermoelectric material for near-room temperature operation. Improvements in material performance are expected from nanostructuring procedures. We present a straightforward and fast method to synthesize already nanostructured pellets that show an...

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Detalles Bibliográficos
Autores: Serrano Sánchez, Federico, Gharsallah, Mouna, Nemes, Norbert Marcel, Biskup Zaja, Nevenko, Varela Del Arco, María, Martínez, José Luis, Fernández Díaz, María Teresa, Alonso, José Antonio
Tipo de recurso: artículo
Fecha de publicación:2017
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/91844
Acceso en línea:https://hdl.handle.net/20.500.14352/91844
Access Level:acceso abierto
Palabra clave:536
Termodinámica
2213 Termodinámica
Descripción
Sumario:Sb-doped Bi2Te3 is known since the 1950s as the best thermoelectric material for near-room temperature operation. Improvements in material performance are expected from nanostructuring procedures. We present a straightforward and fast method to synthesize already nanostructured pellets that show an enhanced ZT due to a remarkably low thermal conductivity and unusually high Seebeck coefficient for a nominal composition optimized for arc-melting: Bi0.35Sb1.65Te3. We provide a detailed structural analysis of the Bi2−xSbxTe3 series (0 ≤ x ≤ 2) based on neutron powder diffraction as a function of composition and temperature that reveals the important role played by atomic vibrations. Arc-melting produces layered platelets with less than 50 nm-thick sheets. The low thermal conductivity is attributed to the phonon scattering at the grain boundaries of the nanosheets. This is a fast and cost-effective production method of highly efficient thermoelectric materials.