Abstract:La0.4Sr0.6Co0.7Fe0.2Nb0.1O3-δ-Gd0.2Ce0.8O2-δ (LSCFN-GDC) with high catalytic performance was synthesized by one-step co-synthesis method for developing a symmetrical reversible solid oxide cell (SOC) electrode. Electrolyte-supported symmetrical SOCs were fabricated by tape-casting and screen-printing methods with La0.8Sr0.2Ga0.83Mg0.17O3-δ (LSGM) as the electrolyte and LSCFN-GDC as both anode and cathode. The configuration of SOC is LSCFN-GDC||LSGM||LSCFN-GDC. Solid oxide fuel cell (SOFC) and solid oxide electrolysis cell (SOEC) modes were used to test the performance of SOCs. The results show that the maximum power densities are 1.036, 0.996, 0.479, and 0.952 W/cm2 under the atmosphere of fuel gas of H2 (3% H2O), H2 (0.01% H2S), CH4, and C3H8 at 850 °C, respectively. The current density at the electrolytic voltage of 1.3 V is 0.943 A/cm2 during the electrolysis of H2 (50% H2O). LSCFN-GDC has good coking-resistance, sulfur-tolerance, and redox stability, and its stable performance can be sustained for 700 h under the atmosphere of H2 (0.01% H2S), CH4, H2 (3% H2O), and H2 (50% H2O). The results indicate that the one-step method is a facile and optimized fabrication procedure of electrode and LSCFN-GDC||LSGM||LSCFN-GDC SOCs have great potential in further application.