Synthesis and Catalytic Property of Au/Titania Nanocomposites on the Photolytic Degradation of Methyl Orange

Abstract

Tetra-n-butyl titanate was used to synthesize a precursor titania (TiO2) gel by sol-gel method, which was successfully employed to prepare TiO2 powders by calcinating at variant temperatures. The anatase phase TiO2 was obtained at 500°C according to XRD analysis, which was selected as the support for nanogold catalysts. The reduction of HAuCl4 by tetrakis(hydroxymethyl)phosphonium chloride (THPC) was used to immobilize Au nanoparticles on the as-prepared anatase TiO2, which was compared with the normal deposition-precipitation (DP) method. SEM and UV-vis analyses indicate that the THPC-Au/TiO2 has a larger loading of Au and stronger photocatalytic activity than the DP-Au/TiO2, which offers a simple way to prepare strong Au/TiO2 photocatalysts with low Au consumption.