Imidazolate-mediated synthesis of hierarchical flower-like Co3O4 for the oxidation of toluene

Cobalt oxide (Co 3 O 4 ) materials with specific structure have shown great potential as highly efficient catalysts in the oxidation reactions. In this work, a novel hierarchical flower-like Co 3 O 4 was synthesized by the imidazolate-induced hydrothermal and subsequent thermolysis method. The effect of reaction parameters as well as the phase evolution of the flower-like structure was investigated in detail. For comparison, a rod-like Co 3 O 4 was also prepared with urea under similar conditions. The morphology-dependent effect of Co 3 O 4 towards toluene oxidation was studied. Moreover, the physicochemical properties of Co 3 O 4 were analyzed by various characterization techniques. The flower-like Co 3 O 4 catalyst presented a higher catalytic activity for toluene oxidation than the rod-like Co 3 O 4 , which was associated with hierarchical flower-like morphology, reactive exposed planes, abundant adsorbed oxygen species at surface and better low-temperature reducibility.