High Efficient and Stable Thiol-Modified Dendritic Mesoporous Silica Nanospheres Supported Gold catalysts for Gas-phase Selective Oxidation of Benzyl Alcohol with Ultra-Long Lifetime

Thiol-modified dendritic mesoporous silica nanospheres (DMSNs) supported Au catalyst were facilely prepared and used in gas-phase selective oxidation of benzyl alcohol with O2 as the oxidant. The Au/DMSNs-4.4%SH catalyst with low loading of Au (~2%) and proper amount of thiol ligand (~4.4%) achieved high conversion of benzyl alcohol (Conv. 91%) and selectivity for benzaldehyde (Sel. 98%) and unprecedented lifetime up to 820 h at 250 °C. The dramatically increased lifetime is the consequence of the strong stabilization of active gold nanoparticles by thiol ligand and the effective mass diffusion of DMSNs with opened three-dimensional mesoporous networks.