Pd–La0.6Sr0.4Co0.2Fe0.8O3– composite as active and stable oxygen electrode for reversible solid oxide cells

To promote the electrocatalytic activity and stability of traditional La0.6Sr0.4Co0.2Fe0.8O3–δ (LSCF) oxygen electrodes in reversible solid oxide cells (RSOCs), conventional physical mixed method was used to prepare the Pd-LSCF composite oxygen electrode. The cell with Pd-LSCF|GDC|YSZ|Ni-YSZ configuration shows perfect electrochemical performance in both solid oxide fuel cell (SOFC) mode and solid oxide electrolysis cell (SOEC) mode. In the SOFC mode, the cell achieves a power density of 1.73 W/cm2 at 800 °C, higher than that of the LSCF oxygen electrode with 1.38 W/cm2. In the SOEC mode, the current density at 1.5 V is 1.67 A/cm2 at 800 °C under 50 vol% steam concentration. Moreover, the reversibility and stability of the RSOCs were tested during 192 h long-term reversible operation. The degradation rate of the cell is only 2.2%/100 h and 2.5%/100 h in the SOEC and the SOFC modes, respectively. These results confirm that compositing Pd with the LSCF oxygen electrode can considerably boost the electrochemical performance of LSCF electrode in RSOCs field.