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.

Keywords:

• Au/TiO₂ nanocomposite
• deposition-precipitation
• methyl orange
• photolysis
• reduction

Acknowledgments

The work was supported by the National Natural Science Foundation of China (Grant No. 21163004), the Guangxi Natural Science Foundation (Grant No. 2010GXNSFC013006), and the Scientific Research Foundation for Returned Scholars, Ministry of Education of China.