(La0.75Sr0.25)0.95Mn0.5Cr0.5O3 as the cathode of solid oxide electrolysis cells for high temperature hydrogen production from steam

Ni/YSZ cathodes are generally utilised for steam electrolysis; however such electrodes can only operate under reducing conditions. In an atmosphere with low content of H2 or without H2, especially under low current conditions, cathodes based on (La0.75Sr0.25)0.95Mn0.5Cr0.5O3 (LSCM) provide a promising alternative. Solid Oxide Electrolysis Cells with LSCM cathodes were tested under external potential load at temperatures between 750 °C and 1000 °C using 3% steam/Ar/4% H2 and 3% steam/Ar, and promising polarisation impedance data were obtained in both atmospheres, especially in the gas without H2. I–V curves from LSCM cells in 3% steam/Ar have sigmoidal shape indicative of chemical changes in the LSCM occurring in addition to electrolysis. Despite these features, considerably improved performance is found compared to Ni-based electrodes in low hydrogen conditions.