Preparation of honeycomb porous La_(0.6)_Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3_δ)-Gd_(0.2)Ce_(0.8)O__(2-δ) composite cathodes by breath figures method for solid oxide fuel cells

摘要

Honeycomb porous La_(0.6)_Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3_δ)-Gd_(0.2)Ce_(0.8)O__(2-δ) (LSCF-GDC) composite cathodes are prepared using the breath figures (BFs) method with nontoxic and easily available water droplets as templates. The fabrication of honeycomb porous membranes is realized in a relatively humid environment, using a volatile solvent. The microstructure and morphology of the membranes produced are investigated by scanning electron microscopy (SEM). The SEM micrographs suggest that experimental conditions, such as ambient temperature, relative humidity, and concentration of polymer and LSCF-GDC powder, which have direct influence on the solvent evaporation affects the pore structure of the porous membranes. Electrochemical impedance spectroscopy (EIS) is used to evaluate the polarization resistance of LSCF-GDC composite cathodes prepared at different experimental conditions. The honeycomb porous LSCF-GDC composite cathode showing average pore diameter of 10 μm illustrates the lowest polarization resistance.