Electrochemical Performance of PrBaCo2O5+δ and Sm0.5Sr0.5CoO3-δ Infiltrated Ce0.9Gd0.1O1.95 Cathodes

Cathodes with PrBaCo2O5+delta (PBC) and Sm0.5Sr0.5CoO3-delta (SSC) infiltrated on Ce0.9Gd0.1O1.95 (CGO) backbones are prepared using metal nitrates as precursors and ethanol as wetting agent. Electrochemical impedance spectra (EIS) are measured from cathode/CGO/cathode symmetrical cells in 400-650 degrees C under humidified air. The results indicate that interfacial area specific resistance (ASR) value decreases and then increases with infiltrate loading and minimum values occur at 50 wt.% loading (relative to sum of infiltrate and backbone) for both PBC and SSC infiltrates. ASR values of PBC infiltrated cathodes are lower than that of corresponding SSC infiltrated cathodes in general, and in particular ASR values as low as 1.36 x 10(-2) and 2.27 x 10(-2) Omega cm(2) are obtained at 650 degrees C in air for 50 wt.% PBC and 50 wt.% SSC infiltrated cathodes, respectively. Conductivity values of CGO electrolyte increase with infiltrate loading and agree with the reported values when the loading reaches 50 wt.%.