LAUSR

Abstract The degradation mechanism of ceramic matrix materials used as molten hydroxide electrolyte support for steam electrolysis cells, is not well documented. In this study, we have investigated the structural and chemical stability of non-oxide and oxide ceramics (SiC, YSZ, Li2ZrO3, LiAlO2, and SrZrO3) in the presence of molten hydroxide under oxidizing and reducing conditions with humidity levels of 3 and 85% at 550 °C. SiC, YSZ, Li2ZrO3 and LiAlO2 showed structural and chemical changes due to dissolution of the ceramic particles in the hydroxide melt followed by precipitation. The SrZrO3 powder, on the other hand, remained both chemically and structurally stable during 500 h test under both oxidizing and reducing atmospheres. The findings of a stable ceramic matrix in molten hydroxide contribute to the enhancement of the durability and performance of intermediate temperature water electrolysis system.