To systematically investigate the influence of electrolyte substrates on Sr-segregation and SrSO4 formation in (LaSr)(CoFe)O3 (LSCF) cathodes in solid oxide fuel cells, model thin films were grown on Gd-doped ceria (GDC) and on Y-doped BaZrO3 (BZY) electrolytes by pulsed laser deposition and heat treated at 800–1000 °C in synthetic air with a trace amount of SO2. A severe SrSO4 formation was observed in LSCF on GDC as compared with the BZY, especially at low temperature. The difference in Sr-segregation and SrSO4 formation on the LSCF was discussed in relation to Sr diffusion and related elemental redistribution across the interfaces.
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This work is supported in part by the New Energy and Industrial Development Organization (NEDO) project, “Basic study on the rapid evaluation method of SOFC durability”.
The supplementary material for this article can be found at https://doi.org/10.1557/mrc.2018.208.
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De Vero, J.C., Yokokawa, H., Develos-Bagarinao, K. et al. Influence of electrolyte substrates on the Sr-segregation and SrSO4 formation in La0.6Sr0.4Co0.2Fe0.8O3_δ thin films. MRS Communications 9, 236–244 (2019). https://doi.org/10.1557/mrc.2018.208