Composite cathode based on Fe-loaded LSCM for steam electrolysis in an oxide-ion-conducting solid oxide electrolyser

Abstract

Composite cathodes based on La0.75Sr0.25Cr0.5Mn0.5O3−δ (LSCM) can perform direct steam electrolysis; however, the insufficient electro-catalytic activity still limits the electrode performances and Faradic efficiency. In this work, Fe catalyst is loaded onto an LSCM-based composite fuel electrode and studied for direct steam electrolysis. The dependence of the conductivity of LSCM on temperature and on oxygen partial pressure is investigated and correlated to the cathode performance. The loading of Fe catalysts significantly improved the electrode performance and the Faradic efficiency without the flow of reducing gas over the cathode. The current efficiency is enhanced by 30% and 40% compared to the values with the bare LSCM-based cathode at 800 °C in 3%H2O/5%H2/Ar and 3%H2O/Ar, respectively. The synergetic effect of catalytic-active Fe and redox-stable LSCM leads to excellent stability and better cathode performance for direct steam electrolysis.