Electrochemical Performance of PrBaCo₂O_5+δ and Sm_0.5Sr_0.5CoO_3−δ Infiltrated Ce_0.9Gd_0.1O_1.95 Cathodes

Abstract

Abstract Cathodes with PrBaCo 2 O 5+ δ (PBC) and Sm 0.5 Sr 0.5 CoO 3− δ (SSC) infiltrated on Ce 0.9 Gd 0.1 O 1.95 (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 °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 × 10 −2 and 2.27 × 10 −2 Ω cm 2 are obtained at 650 °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.%.