Phase assembly and electrical conductivity of spark plasma sintered CeO2–ZrO2 ceramics

Ce x Zr1−x O2 (x = 0.10, 0.16 and 0.33) nanocrystalline powders were obtained by a two-step synthesis technique and sintered by spark plasma sintering (SPS). As consequence of the reduction of Ce4+ to Ce3+ species by carbon in the graphite environment in SPS, phase assemblies including tetragonal, m...

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Detalhes bibliográficos
Autores: Poyato Galán, Rosalía, Cruz Torres, Sylvia Andrea, Cumbrera Hernández, Francisco Luis, Moreno, Berta, Chinarro Martín, Eva, Odriozola Gordón, José Antonio
Formato: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2014
País:España
Recursos:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/73631
Acesso em linha:https://hdl.handle.net/11441/73631
https://doi.org/10.1007/s10853-014-8361-6
Access Level:acceso abierto
Palavra-chave:CeO2–ZrO2
Spark plasma sintering
Pyrochlore
Electrical conductivity
Descrição
Resumo:Ce x Zr1−x O2 (x = 0.10, 0.16 and 0.33) nanocrystalline powders were obtained by a two-step synthesis technique and sintered by spark plasma sintering (SPS). As consequence of the reduction of Ce4+ to Ce3+ species by carbon in the graphite environment in SPS, phase assemblies including tetragonal, monoclinic and pyrochlore phases were generated in the ceramics during the sintering process. The electrical conductivity was highly dependent on phase assembly and atmosphere (N2, H2 and O2). A significant decrease in the activation energy was noticed in the ceramics with high pyrochlore content when measuring the conductivity in H2 atmosphere, consequence of the strong reduction promoted in these ceramics during the measurement. Equal conduction behavior with similar activation energy was observed in all the ceramics when measuring in O2 atmosphere