A La2NiO4+δ/Ce0.8Sm0.2O2-δ/La2NiO4+δ symmetrical cell was prepared using a screen-printing method by sintering at 1100 oC. The electrochemical properties of the cell were examined by the impedance spectroscopy technique under zero dc bias in air between 500-700 oC. The La2NiO4+δ electrodes displayed satisfactory chemical and thermodynamic compatibilities with the Ce0.8Sm0.2O2-δ electrolyte. A comparatively low area specific resistance of 0.18 Ω cm2 at 700 oC was determined for the La2NiO4+δ electrodes. Scanning electron microscope (SEM) observation revealed that the La2NiO4+δ electrodes showed a reasonable porosity, a well-necked connection among fine grains and a tight adhesion to the electrolyte support. The desired microstructure is regarded to be responsible for the superior electrode properties of the La2NiO4+δ layers.
Keywords: La2NiO4+δ, Mixed conductor, Electrode properties, Screen-printing, Ce0.8Sm0.2O2-δ electrolyte.