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

Abstract A facile and green template-free hydrothermal method was conducted to controllably synthesize spinel type cobalt oxides (Co3O4) with cube, truncated octahedron and octahedron morphologies. The catalytic performance over various shapes of catalysts was investigated towards CO oxidation. Among of them, the Co3O4 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 Co3+ 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.