Effect of microstructure on electrical and mechanical properties of La5.4WO12-delta proton conductor

[EN] The relationships between microstructural characteristics and electrical as well as mechanical properties of La5.4WO12-delta (LWO54) materials were studied. Polycrystalline LWO54 samples revealed identical transport mechanisms regardless of the sample microstructure. The studied samples show pr...

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Detalhes bibliográficos
Autores: Deibert, Wendelin, Stournari, Vasiliki, Ivanova, Mariya E., Malzbender, Juergen, Beck, Tilman, Singheiser, Lorenz, Guillon, Olivier, Meulenberg, Wilhelm A., Escolástico Rozalén, Sonia|||0000-0002-7097-2425, Serra Alfaro, José Manuel|||0000-0002-1515-1106
Formato: artículo
Fecha de publicación:2018
País:España
Recursos:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/190458
Acesso em linha:https://riunet.upv.es/handle/10251/190458
Access Level:acceso abierto
Palavra-chave:Proton-Conducting ceramic membranes
Lanthanum tungstate
Mechanical properties
Conductivity
Strength
Creep
Descrição
Resumo:[EN] The relationships between microstructural characteristics and electrical as well as mechanical properties of La5.4WO12-delta (LWO54) materials were studied. Polycrystalline LWO54 samples revealed identical transport mechanisms regardless of the sample microstructure. The studied samples show predominately proton conductor behaviour below 800 degrees C and become predominant n-type and oxygen ion conductors above this temperature. The magnitude of the total conductivity is enhanced with larger grain size and lower porosity. Young's modulus decreased by 20% with increasing temperature up to 1000 degrees C regardless of grain size and atmosphere. Fracture strength was determined via ring-on-nng bending tests, yielding values that strongly depended on microstructural characteristics and homogeneity of the microstructure. Elevated temperature deformation studies revealed that creep is governed by cation diffusion mechanism.