Electrodes for Solid Oxide Fuel Cells Based on Infiltration of Co-Based Materials

The electrochemical performance of cathodes produced by infiltration of nitrates corresponding to the nominal compositions Co3O4, LaCoO3, and La0.6Sr0.4Co1.05O3-delta into porous backbones of Ce0.9Gd0.1O1.95 has been studied. Characterization by electrochemical impedance spectroscopy at 600 degrees C in air revealed that the lowest electrode polarization (R-p) value is obtained for La0.6Sr0.4Co1.05O3-delta (0.062 Omega cm(2)), followed by LaCoO3 (0.079 Omega cm(2)), and Co3O4-infiltrated cathodes (0.27 Omega cm(2)). The surprisingly good performance of LaCoO3- and Co3O4-infiltrated cathodes demonstrate the peculiarities encountered at the nanoscale and raise questions on the necessity of Sr doping if the electrocatalyst is formed as nanoparticles using the infiltration technique. (C) 2012 The Electrochemical Society. [DOI:10.1149/2.020204esl] All rights reserved.