Abstract: The Au/TiO2 photocatalysts were prepared by the deposition-precipitation method. Three different crystal forms of TiO2 were used as supports. The influence of crystal form of TiO2 on photocatalytic decomposition of gaseous ozone over Au/TiO2 was studied. The photocatalysts were characterized by ultraviolet-visible diffuse reflectance spectroscopy,X-rayphotoelectron spectroscopy (XPS), and surface photovoltage spectroscopy (SPS). The results showed that the photocatalytic activity of the catalysts was in the order Au/P25>Au/Anatase>Au/Rutile, in agreement with the order of the photocatalytic activity of pure TiO2. The photocatalytic activity of the catalysts increased obviously by loading Au. The results of Au 4f XPS showed that the ability of transferring electron from TiO2 to Au clusters was obviously different in three kinds of TiO2. The synergistic effect was responsible for the different activity of Au/TiO2. The SPS signals were consistent with photocatalytic activity: the stronger the SPS signal, the faster the separation rate of photoinduced electron-hole pairs, the higher the photocatalytic activity.

Key words: crystal form, supported gold catalyst, titania, photocatalytic decomposition, ozone