Pt/Co3O4/3DOM Al2O3: Highly effective catalysts for toluene combustion

Three-dimensionally ordered macro-/mesoporous alumina (3DOM Al2O3)-supported cobalt oxide and platinum nanocatalysts (xPt/yCo(3)O(4)/3DOM Al2O3, Pt mass fraction (x%) = 0-1.4%, Co3O4 mass fraction (y%) = 0-9.2%) were prepared using poly(methyl methacrylate) templating, incipient wetness impregnation and polyvinyl alcohol-protected reduction. The resulting xPt/yCo(3)O(4)/3DOM Al2O3 samples displayed a high-quality 3DOM architecture with macropores (180-200 nm in diameter) and mesopores (4-6 nm in diameter) together with surface areas in the range of 94 to 102 m(2)/g. Using these techniques, Co3O4 nanoparticles (NPs, 18.3 nm) were loaded on the 3DOM Al2O3 surface, after which Pt NPs (2.3-2.5 nm) were uniformly dispersed on the yCo(3)O(4)/3DOM Al2O3. The 1.3Pt/8.9Co(3)O(4)/3DOM Al2O3 exhibited the best performance for toluene oxidation, with a T-90% value (the temperature required to achieve 90% toluene conversion) of 160 degrees C at a space velocity of 20000 mL g(-1) h(-1). It is concluded that the excellent catalytic performance of the 1.3Pt/8.9Co(3)O(4)/3DOM Al2O3 is owing to well-dispersed Pt NPs, the high concentration of adsorbed oxygen species, good low-temperature reducibility, and strong interaction between the Pt and Co3O4 NPs, as well as the unique bimodal porous structure of the support. (C) 2016, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.