Deposition of Au nanoparticles into mesoporous SiO2 SBA-15

Au/SiO2 SBA-15 materials were prepared using supercritical CO2 (scCO2) and by wet impregnation. First, SiO2 was functionalized with thiol groups at different grafting densities 3-(Mercaptopropyl)trimethoxysilane dissolved in scCO2. The support then impregnated HAuCl4·3H2O scCO2 modified EtOH. Wet impregnation of the supports ethanol also performed. Materials calcined 500 °C to remove organic matter promote particle growth. on highest density showed Au NP between 2.5 5 nm homogeneously distributed within mesopores. Slightly larger NPs obtained low a bimodal size distribution particles up 7 located inside mesopores ones 10–20 external surface. A possible reaction mechanism proposed. These can be used catalysis, sensing biomedicine.