The catalytic performance of perovskite composite oxide catalyst La 0.9 K 0.1 CoO3 coated on catalyst supports by traditional solid state reaction method and sol-gel method were investigated by a series of experiments. The result shows that the catalytic performance of the La 0.9 K 0.1 CoO3 perovskite composite oxide catalyst synthesized by sol-gel method is superior to that synthesized by solid state reaction method, having lower ignition temperature of the diesel soot particulates, lower start temperature of NOx treatment, and lower concentration of byproduct CO.
