Cathodic polarization of strontium-doped lanthanum ferrite in proton-conducting solid oxide fuel cell

The cathodic polarization of strontium-doped lanthanum ferrite, La1−xSrxFeO3−α, was studied in the hydrogen-oxygen fuel cell using proton-conducting SrCe0.95Yb0.05O3−α as an electrolyte. The overpotential of La0.7Sr0.3FeO3−α cathode was smaller than those of other perovskite-type oxides such as La0.7Sr0.3MnO3−α and La0.7Sr0.3CoO3−α, and platinum at 773-973 K. The best cathodic performance was obtained for La0.7Sr0.3FeO3−α heat-treated at 1173 K. The cathode resistance of La0.7Sr0.3FeO3−α was independent of pO2 while that of sputtered platinum was proportional to pO2−1/4.