PA-24 Co3O4 Nanorods for Low Temperature Oxidation of Carbon Monoxide

Abstract: Co3O4 nanorods were found to be not only sufficiently active for CO oxidation at a temperature as low as-77℃, but also sustainably stable in a stream of normal feed gases containing moisture. The reaction rate of CO oxidation over the Co3O4 nanorods with very low apparent activation energy of 22 kJ/mol was at least one order of magnitude larger than those over the conventional nanoparticles. High-resolution transmission electron microscopy observation proved that the single crystal Co3O4 nanorods predominantly exposed the {110} planes that favor the presence of octahedrally coordinated Co3+ species, which may act as the active sites for CO oxidation. The above results indicate a possibility of replacing noble metals with morphology-controlled base metal oxides in the currently used catalysts for automotive-emissions control, particularly, during the cold-start transient