Characterisation and photocatalytic properties of titania–silica mixed oxides doped with Ag and Pt

TiO2–SiO2 mixed oxides have been synthesised and modified by Ag and Pt deposition. Due to the effect of the silica on the mixed oxide, the prepared materials presented high surface areas and stabilised anatase as the only crystalline phase after calcination at 700 °C. Even using the same photodeposition experimental conditions, the yield for metal deposition depended highly on the metal considered, being much lower for Ag deposition. XPS studies permitted to estimate metal dispersion and oxidation state of the different samples, being both factors of high importance regarding photocatalytic improvement by metal deposition.

Figure optionsDownload high-quality image (109 K)Download as PowerPoint slideResearch highlights▶ Experimental parameters of photodeposition: high influence on final properties. ▶ Deposition yield and oxidation state depend highly on the kind of deposited metal. ▶ XPS study allows an estimation of the dispersion of metal particles. ▶ Addition of silica leads to surface area and anatase phase stabilisation. ▶ High improvement of photocatalytic activity achieved by Pt photodepostion.