Development of porous cathode powders for SOFC and influence of cathode structure on the oxygen electroreduction kinetics

Meso/macroporous La1−xSrxCoO3−δ powder with the specific surface area higher than 140 m2 g−1 has been synthesized from the corresponding nitrates, using solution thermal decomposition method. These nanopowders have been used for preparation of SOFC cathodes, demonstrating lower oxygen electroreduction activation energy than that for less porous cathodes prepared from the powders synthesized using traditional solid state reaction method. To increase macroporosity of the cathodes the special pore forming agent has been added into the raw cathode paste. The very low total polarization resistance and activation energy values have been obtained for oxygen electroreduction, depending on the cathode porosity and potential applied.