A novel perovskite-based proton conductor for solid oxide fuel cells

A perovskite-based electrolyte, Ca-substituted YAlO3, has been synthesized by the citrate gel process. The conductivity of Y0.9Ca0.1AlO3-δY0.9Ca0.1AlO3-δ has been studied by AC impedance spectroscopy in controlled atmospheres in the temperature range 300–800 °C. The material has been found to be a mixed conductor with dominant p-type electronic conduction at elevated temperatures and a combined protonic conduction below 600 °C in wet conditions. The H/D isotope effect on conductivity confirms the presence of protonic conductivity between 400 and 600 °C.