Physicochemical compatibility of SrCeO{sub 3} with potential SOFC cathodes

Journal Article · Mon Oct 15 04:00:00 EDT 2007 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2007.08.004· OSTI ID:21049513

Tolchard, J ^[1]

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1. Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)

The chemical and physical compatibility of SrCeO{sub 3} is investigated with respect to LaMO{sub 3} (M=Mn, Fe, Co) and La{sub 2-x}Sr{sub x}NiO{sub 4} (x=0, 0.8), via the reaction of fine-grained powder compacts and solid-state diffusion couples. Compositions were chosen so as to give predictive insight into possible candidate materials for all-oxide electrochemical devices. Results show the primary reaction in these systems to be the dissolution of SrO from SrCeO{sub 3} into the LaMO{sub 3}/La{sub 2-x}Sr{sub x}NiO{sub 4}, and corresponding formation of La-doped CeO{sub 2}. Reaction kinetics are observed to be relatively fast, with element profiles suggesting the diffusion of Sr{sup 2+} in ceria to be surprisingly rapid. It is demonstrated that perovskite starting materials represent poor candidates for use with SrCeO{sub 3}, reacting completely to form Ruddlesden-Popper/K{sub 2}NiF{sub 4} type oxides. Reaction with La{sub 2}NiO{sub 4} is less pronounced, and formation of secondary phases suppressed for the composition La{sub 1.2}Sr{sub 0.8}NiO{sub 4}. It is thus concluded that Ruddlesden-Popper type oxides represent good candidate materials for use with a SrCeO{sub 3}-based electrolytes when doped with appropriate levels of Sr. - Graphical abstract: Assessment of the SrCeO{sub 3} proton conductor shows this material to have poor chemical compatibility with LaMO{sub 3} perovskite systems, but predicts coexistence with Ruddlesden-Popper type oxides.

• OSTI ID: 21049513
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 10 Vol. 180; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CATHODES
CERIUM OXIDES
COBALT COMPOUNDS
COMPATIBILITY
DIFFUSION
DOPED MATERIALS
ELECTROCHEMISTRY
IRON COMPOUNDS
LANTHANUM COMPOUNDS
MANGANESE COMPOUNDS
MOLYBDATES
NICKELATES
PEROVSKITE
REACTION KINETICS
SOLID OXIDE FUEL CELLS
STRONTIUM IONS
STRONTIUM OXIDES