Abstract
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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ACKNOWLEDGMENTS
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”.
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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
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DOI: https://doi.org/10.1557/mrc.2018.208