Development of oxygen electrodes for reversible solid oxide fuel cells with scandia stabilized zirconia electrolytes

La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) and La0.8Sr0.2MnO3 − δ (lanthanum strontium manganite)/YSZ (yttria stabilized zirconia) are tested as alternative reversible electrodes in 10Sc1CeSZ (scandia and ceria stabilized zirconia) based cells. Microstructure of the electrodes is optimized to assure good catalytic activity for oxygen reduction in fuel cell mode and oxygen evolution in electrolysis mode. High performance in electrolysis and fuel cell mode was obtained for samples using LSCF (lanthanum strontium cobalt ferrite) and LSM/YSZ electrodes. AC impedance experiments performed under different potential loads reveal the reversibility for both electrodes. At 850 °C, the sample with the LSCF electrode becomes completely reversible and the ASRtotal of the cell in both electrolysis and fuel cell mode is 0.73 Ω cm2.