Evaluation of La2Ce2O7 (LCO) Protection Layer for Proton Conducting Electrolyte

Abstract

Due to the susceptible reaction BaCeO3-based proton-conductors toward steam and carbon dioxide, La2Ce2O7(LCO) is proposed as a protect layer on top of solid electrolyte since LCO has shown high proton conductivity with adequate stability against steam. In the study, La(NO3)3·6H₂O and Ce(NO3)3·6H₂O were used as precursors to obtain La2Ce2O7(LCO). Particle size analyzer and XRD are applied to analysis this result. From the XRD analysis, it can be seen at the temperature range above 900°C, the reflections representing fluorite-structured LCO appeared with other reflections from BaCe0.5Zr0.3Y0.2O3-δ(BCZY) perovskite substrate. The result can also demonstrate that there is no reaction between LCO layer and BCZY substrate. It is suggested that LCO exhibits good chemical compatibility with BCZY. This synergic bilayer electrolyte design may be a feasible design to overcome the instability of Zr- or Ce-rich Ba(CeZr)O3−δ electrolysis cells against steam and CO2 for better long-term performance. The stability and protection of La2Ce2O7(LCO) on BaCe0.5Zr0.3Y0.2O3-δ(BCZY) will be evaluated based on structural and electrical properties measurement under humid and CO2 containing environment as function of time and temperatures.