Facile and green template-free synthesis of morphology-controllable Co3O4 catalysts for CO oxidation

A facile and green template-free hydrothermal method was conducted to controllably synthesize spinel type cobalt oxides (Co 3 O 4 ) with cube, truncated octahedron and octahedron morphologies. The catalytic performance over various shapes of catalysts was investigated towards CO oxidation. Among of them, the Co 3 O 4 cube performs the best catalytic activity, which can even be comparable to those of certain noble metal catalysts. The phenomenon might be ascribed to the synergistic effects of exposed Co 3+ active sites and surface oxygen distribution on the surface of the catalyst. The results may provide significant insights for the fabrication of metal oxide catalysts for CO oxidation .