Electrochemical evaluation of La2NiO4+δ as a cathode material for intermediate temperature solid oxide fuel cells

• Effects of preparation conditions on electrode properties of La2NiO4+δ are studied.
• The optimal conditions for preparing La2NiO4+δ cathode are determined.
• The single cell with La2NiO4+δ cathode shows modified electrochemical performance.
• Applying an Au layer on La2NiO4+δ cathode surface improves the performance.

La2NiO4+δ powders were synthesized using a polyaminocarboxylate complex precursor method. La2NiO4+δ electrodes were prepared on Ce0.8Sm0.2O1.9 (SDC) substrates using a screen-printing technique. The microstructure feature and electrocatalytic activity of the electrodes were investigated with respect to the calcination temperature of the starting powders and sintering temperature of the electrodes. The effects of microstructure features on the electrochemical properties of La2NiO4+δ electrodes have been inspected. Moreover, the electrochemical performance of the La2NiO4+δ cathode has been evaluated based on a Ni-SDC anode supported single cell. The single cell showed a modified electrochemical performance compared with the literature results, attaining a maximum power density of 295 mW cm−2 at 800 °C. For the single cell, applying an Au layer onto the La2NiO4+δ cathode led to an evident reduction of ohmic resistance and a substantial enhancement of the maximum power density to 464 mW cm−2.