Abstract: In this paper, ZnO, TiO₂ and Zn ²⁺ doped TiO₂ nanoparticles were prepared by chemical precipitation and sol-gel method, respectively, and characterized by means of XRD and FS spectra. We mainly investigated the relationships between the photoluminescence performance and photocatalytic activity of the as-prepared samples as well as the photoluminescence mechanism. The results show that ZnO and TiO₂ nanoparticles exhibit obvious FS signals by excitation with the light of higher energy than band-gap energy, and the intensity of FS signals decreased with increasing the temperature of thermal treatment. It should be pointed that the FS signal structure of ZnO and TiO₂ samples are similar, which was possibly related to their similar structure of electronic energy band. It could be demonstrated that FS signals are mainly originated from the energy level of exciton and surface states resulting mainly from surface oxygen vacancies and adsorbed oxygen species. Zn ²⁺ dopant made the FS intensity of TiO₂ nanoparticle increase, due to the increase in the content of surface oxygen vacancies and defects. In addition, during the experiment of photocatalytic oxidation of phenol, the orders of the photocatalytic activity of as-prepared samples were the same as that of the FS intensity, namely, the stronger the FS intensity, the higher the activity. This was the reason that FS spectra mainly resulted from the surface oxygen vacancies during the photoluminescence process, while surface oxygen vacancies were favourable for the photocatalytic oxidation reaction.

Key words: ZnO, TiO₂, Nanoparticle, Photoluminescence, Photocatalysis