La2 − x Sr x NiO4 + δ materials were investigated as cathodes for the electrochemical reduction of oxygen on a Ce1.9Gd0.1O1.95 (CGO10) electrolyte using cone-shaped electrodes together with electrochemical impedance spectroscopy. The area-specific resistance (ASR) of the La2 − x Sr x NiO4 + δ nickelates towards the reduction of oxygen is equal to the ASR of perovskites; however, it is not as low as for the best Fe–Co-based perovskites. The lowest ASR is found for the compound La1.75Sr0.25NiO4 + δ with an ASR of 23.8 Ωcm2 measured on a cone-shaped electrode in air at 600 °C. It is suggested that difference in oxide ionic conductivity of the nickelates is the main cause for the different activity of the nickelates towards the electrochemical reduction of oxygen.
- Fuel Cells and hydrogen
- Flue gas purification