The O transport properties and the performance of the composite La0.6Sr0.4Co0.2Fe0.8O3−δ/Ce0.8Ge0.2O2−x, were investigated. Using the isotopic exchange depth profiling technique with secondary ion mass spectroscopy, the O tracer diffusion coefficient, D* and the surface exchange coefficient k were measured. The measured D* values of the composite material were higher than that of the non-composite diffusion coefficient values, while the k values were similar to the non-composite material at all temperatures. The area-specific resistance of the porous composite cathode was measured by impedance spectroscopy. A performance improvement was observed below 650C when compared to a non-composite cathode. This improvement was mainly attributed to the improvement in the O tracer diffusion coefficient of the composite.

Oxygen Transport in La0.6Sr0.4Co0.2Fe0.8O3−δ/Ce0.8Ge0.2O2−x Composite Cathode for IT-SOFCs. A.Esquirol, J.Kilner, N.Brandon: Solid State Ionics, 2004, 175[1-4], 63-7