A-site and B-site co-doped PrBaFe2O5+δ double perovskite as a symmetrical electrode of solid oxide fuel cell with potential of CO2 electrolysis

In this study, PrBa0.5Sr0.5Fe1.9Ge0.1O5+δ (PBSFG), the Sr and Ge doped PrBaFe2O5+δ (PBF), is investigated as a symmetrical electrode of solid oxide cells (SOCs). PBSFG has the potential to be a promising symmetrical electrode in SOCs owing to its high catalytic performance with redox stability. The concentration of oxygen vacancies and surface exchange coefficient of PBSFG are better than that of PBF. The results indicate that PBSFG exhibits not only adequate performance in the fuel cell, with a maximum power density of 1.05 W cm−2 at 800 °C, but also enhanced CO2 electrolysis performance, compared to the PBF. Specifically, in the CO2-electrolysis mode, a maximum current density of 825 mA cm−2 is measured at 850 °C and 1.5 V, which is substantially higher than that of 370 mA cm−2 measured for undoped PBF. These results demonstrate the effectiveness of Sr and Ge doping in PBF to improved CO2 electrolysis performance and notable fuel cell performance.