Effects of impurities on silver–(ZrO2)0.92(Y2O3)0.08 interface morphology in solid oxide cells

Material interactions at elevated temperatures are major contributors to long-term degradation in solid oxide cells (SOC). The use of silver in SOC electrodes is promising due to its good catalytic activity at reduced operating temperatures and chemical stability with other SOC materials. However, no significant studies have been conducted on the interfaces between silver-based electrodes and common SOC electrolyte materials such as yttria-stabilized zirconia (YSZ). A symmetric cell configuration with applied voltage bias has been used to investigate interfaces between silver-based electrodes and YSZ electrolytes at 750 °C. Surface porosity and undulations, as well as trace impurities were observed on the YSZ surfaces using electron microscopy and energy dispersive X-ray spectroscopy. The applied voltage bias enhances the migration of impurities from the electrodes to the silver–YSZ interfaces. The impurities affect the YSZ surface energy characteristics, leading to YSZ surface diffusion and undulation formation.