Preparation of Au/TiO2 catalyst by a liquid-phase reduction method for preferential oxidation of carbon monoxide in a hydrogen rich-stream (CO-PROX reaction)

Abstract

Au nanoparticles supported on TiO2 were prepared by a liquid-phase reduction method using HAuC1(4) 3H(2)O as the Au precursor, TiO2 as the support, a solution of ethylene glycol/water as solvent and reducing agent and sodium citrate as reducing agent and stabilizer. The Au/TiO2 catalysts were prepared usmg different routes and characterized by Energy-dispersive X-ray spectroscopy, X-ray diffraction and Transmission Electron Microscopy and tested for preferential oxidation of carbon monoxide in hydrogen-rich stream (CO-PROX reaction). The way that the Au precursor, the TiO2 support and the sodium citrate is added to the ethylene glycol/water solution strongly influences the Au nanoparticle sizes and the catalytic activity of the obtained materials.