关键词: 磷修饰, 氧化钛, 光催化, 热稳定性, 抗菌

Abstract: The phosphorous-modified TiO₂ (P-TiO₂) was synthesized by a hydrothermal method. The as-prepared P-TiO₂ was evaluated for the degradation of methylene blue, the dechlorination of 4-chlorophenol, and the inactivation of Escherichia coli. In all these experiments, P-TiO₂ shows superior activity compared with pure TiO₂ and even better activity than the commercially available P25 in most cases. By carrying out methylene blue degradation in the presence of different scavengers, •OH radicals were found to be the dominant reactive oxidizing species. The excellent performance of P-TiO₂ was correlated with its pronounced ability to generate •OH radicals under illumination. We also found that P-TiO₂ is extraordinarily stable against annealing. Its transformation from anatase to rutile does not occur until calcination as high as 950 ºC. This phase transformation is retarded since the phosphate species on the surface of the particles acts as a barrier to grain boundary nucleation. This peculiar feature of P-TiO₂ gives it reliable performance during water decontamination even after calcination at 900 ºC since it retains a 100% anatase phase at this stage.

Key words: phosphorous modification, titanium dioxide, photocatalysis, thermal stability, antibacterial