A novel complex nano-structured Au@TiO2 gold catalyst has been prepared. Au precursor could be transformed into Au@TiO2/MCM-22 with the complex nano-structured using two different methods. Samples were characterized by XRD, FT-IR, UV-vis, TEM, ICP-AES and N2 adsorption-desorption. It is found that gold was anchored on the TiO2/MCM-22 as small size and uniform particles with the average diameters in the range of 5 - 9 nm. Catalytic results show that such nano-gold catalysts display excellent catalytic performance for cyclohexane oxidation. Au@TiO2/MCM-22 catalyst with the gold content of 0.5 wt% exhibits extremely exceptionally catalytic activity (12.81%) and high turnover frequency (52,121 h-1), which may be ascribed to the synergistic effects of Au and TiO2 in the complex nano-structured catalyst Au@TiO2/ MCM-22. Because of the strong metal support interaction, aggregation of active sites (Au nanoparticles) during the oxidation reaction is effectively prohibited and the catalytic activity is essentially retained.
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