abstract
A series of alkaline-earth aluminosilicate glass-ceramics (GCs) were appraised with respect to their suitability as sealants for solid oxide fuel cells (SOFCs). The parent composition with general formula Ca(0.9)MgAl(0.1)La(0.1)Si(1.9)O(6) was modified with Cr(2)O(3) and BaO. The addition of BaO led to a substantial decrease in the total electrical conductivity of the GCs, thus improving their insulating properties. BaO-containing GCs exhibited higher coefficient of thermal expansion (CTE) in comparison to BaO-free GCs. An extensive segregation of oxides of Ti and Mn, components of the Crofer22 APU interconnect alloy, along with negligible formation of BaCrO(4) was observed at the interface between GC/interconnects diffusion couples. Thermal shock resistance and gas-tightness of GC sealants in contact with yttria-stabilized zirconia electrolyte (8YSZ) was evaluated in air and water. Good matching of CTE and strong, but not reactive, adhesion to the solid electrolyte and interconnect, in conjunction with a high level of electrical resistivity, are all advantageous for potential SOFC applications. (C) 2009 Elsevier B. V. All rights reserved.
keywords
CRYSTALLIZATION
subject category
Chemistry; Electrochemistry; Energy & Fuels; Materials Science
authors
Goel, A; Tulyaganov, DU; Kharton, VV; Yaremchenko, AA; Ferreira, JMF
our authors
Aleksey Yaremchenko
Principal Researcher
José Maria da Fonte Ferreira
Associate Professor with Aggregation
Vladislav Kharton
Invited Principal ResearcherGroups
3 - Carbon Materials, Composites and Functional Coatings
5 - Biomedical and Biomimetic Materials
acknowledgements
This study was financially supported by University of Aveiro, CICECO and FCT, Portugal (SFRH/BD/37037/2007).