Abstract: The influence of Pt as a promoter on the photocatalytical performance of nitrogen-doped TiO₂ was described. The sample was characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-Vis diffuse reflectance spectroscopy, photoelectrochemistry, and photoluminescence. The degradation of methyl orange in aqueous solution under visible light irradiation was used to evaluate the photocatalytic activity of the sample. The modification of N-TiO₂ with Pt did not change the crystal structure and the mesoporous structure of TiO₂. The loading of Pt enhanced the material absorption in visible light region, which is assigned to background absorption that has detrimental effect on photocatalytic activity. However, the highly dispersed Pt on the surface of N-TiO₂ remarkably altered the surface structure (surface state) of N-TiO₂, contributing largely to the enhanced photocatalytic activity of nitrogen-doped TiO₂.

Key words: nitrogen doped, titania, promoter, platinum, photocatalyst, visible light degradation