Improved crack resistance and thermal conductivity of cubic zirconia containing graphene nanoplatelets

Composites of 8 mol.% yttria-stabilized zirconia (8YSZ) with graphene nanoplatelets (GNP) have been pointed as alternative interconnectors in SOFC due to their mixed ionic-electronic conduction. Here we show that GNP addition provides rising crack-resistance behavior, with long crack toughness up to...

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Detalhes bibliográficos
Autores: Gómez-Gómez, A., Ramírez, C., Llorente, J., Garcia, A., Moreno Pedraz, Pablo Manuel, Reveron, H., Chevalier, J., Osendi, M.I., Belmonte, M., Miranzo, P.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:España
Recursos:Universidad de Salamanca (USAL)
Repositorio:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/146597
Acesso em linha:http://hdl.handle.net/10366/146597
Access Level:acceso abierto
Palavra-chave:Zirconia
Graphene nanoplatelets
Composites
R-curve
Thermal conductivity
Descrição
Resumo:Composites of 8 mol.% yttria-stabilized zirconia (8YSZ) with graphene nanoplatelets (GNP) have been pointed as alternative interconnectors in SOFC due to their mixed ionic-electronic conduction. Here we show that GNP addition provides rising crack-resistance behavior, with long crack toughness up to 78% higher than that of 8YSZ, also improving its thermal conductivity (up to 6 times for the in-plane direction). Toughness versus crack length is measured for 7 and 11 vol.% of GNP using single edge V-notched beam technique and ultrashort pulsed laser notching; and thermal behavior is analyzed by the laser flash method. Materials also have highly anisotropic coefficient of thermal expansion. These properties contribute to enhance their performance under the harsh operating conditions of SOFC, as thermal residual stresses could be reduced while significantly improving the system mechanical stability. Moreover, the heat transfer may be enhanced especially along the interface direction which would increase the system efficiency.