Designing a dumbbell-brush-type Co3O4 for efficient catalytic toluene oxidation

A series of cobalt oxide (Co3O4) catalysts in dumbbell-brush-type, mesoporous nanosheets and nanorods morphologies were successfully prepared and used as catalysts for toluene oxidation. Tailoring Co3O4 morphology not only changed their physico-chemical properties but also remarkably enhanced their catalytic performance, and the formation of oxygen species of different reactivity. Dumbbell-brush-type Co3O4 exhibited the best catalytic activity due to abundant surface Co3+ species, which contributed to superficial oxygen mobility and the formation of more reactive oxygen species. In situ DRIFTS studies confirmed the presence of key reaction intermediates, such as benzaldehyde, benzoate, carbonate and formate species.