First principles study of Cr poisoning in solid oxide fuel cell cathodes: Application to (La,Sr) CoO3

- Chromium poisoning in (La,Sr) CoO3 is studied employing first principles thermodynamics.
- Cr poisoning by-product is observed for a wide range of experimental CrO3 P-T conditions.
- This method can be extended to identify reaction energetics of other multicomponent systems.

Solid oxide fuel cell (SOFC) systems provide efficient and clean power. Chromium poisoning is known to deteriorate the performance of the SOFC cathodes such as La1−xSrxCoO3 (LSCO) due to the formation of undesired products. We identify the reaction products when LSCO is in a CrO3 and O2 atmosphere using first principle thermodynamics, with the assumption that gas-phase CrO3 is the Cr source. Our results correctly identify SrCrO4 as the primary Cr poisoning product as observed in experiments and also provides temperature-pressure regimes under which Cr poisoning effects may be avoided.

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