Hierarchical Co 3 O 4 nanostructures in-situ grown on 3D nickel foam towards toluene oxidation

Abstract Herein, a facile strategy for the in-situ growth of Co-based oxide precursors with unique hierarchical architectures oriented aslant or perpendicular to the Ni surfaces was reported. Toluene was chosen as probe molecule to evaluate their catalytic performance over the synthesized integrated Co-based oxide catalysts. The morphology of integrated Co-based oxide catalysts contained intercrossed frizzy nanosheets (NS), nanowires (NW), columnar nanoclusters (NC) and coral-like microspheres. The structure-performance relationship (SPR) is further confirmed via using H 2 -TPR, XPS, Raman spectrum. The Co 3 O 4 NC on Ni foam exhibited the excellent catalytic activity for toluene oxidation (T 100  = 270 °C, 50 °C lower than that of Co 2 AlO 4 arrays with coral-like microspheres). The excellent catalytic performance of Co 3 O 4 NC catalyst might be resulted from its lower-temperature reducibility, lattice distortion of spinel structure and abundant surface-adsorbed oxygen. The findings of this work provide a new perspective on the design of the high-efficiency integrated catalysts for VOCs combustion.