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

To promote the electrocatalytic activity and stability of traditional La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3– 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/cm 2 at 800 °C, higher than that of the LSCF oxygen electrode with 1.38 W/cm 2 . In the SOEC mode, the current density at 1.5 V is 1.67 A/cm 2 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.