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

Abstract

The electrochemical performance of cathodes produced by infiltration of nitrates corresponding to the nominal compositions Co3O4, LaCoO3, and La0.6Sr0.4Co1.05O3−δ into porous backbones of Ce0.9Gd0.1O1.95 has been studied. Characterization by electrochemical impedance spectroscopy at 600◦C in air revealed that the lowest electrode polarization (Rp) value is obtained for La0.6Sr0.4Co1.05O3−δ (0.062cm2), followed by LaCoO3 (0.079cm2), andCo3O4-infiltrated cathodes (0.27cm2). 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. ©2012 The Electrochemical Society