Abstract: A B-S-co-doped TiO2 photocatalyst (TiO2-B-S) was prepared by the hydrothermal method.X-raydiffraction, ultraviolet-visible diffuse reflectance spectroscopy, andX-rayphotoelectron spectroscopy were applied to characterize the crystalline structure, light absorbing ability, and the chemical state of boron and sulfur in the photocatalysts. The results of photocatalytic degradation of methyl orange demonstrated that the TiO2-B-S catalyst prepared at 240 ℃ for12 hexhibited the highest photocatalytic activity, and the degradation ratio of methyl orange were 99.8% and 81% under UV light irradiation for 50 min and sunlight irradiation for 230 min, respectively. The characterization results revealed that TiO2-B-S is in conformity with the anatase TiO2, and the doping of boron and sulfur ions could efficiently inhibit the grain growth. Doped boron was present as the form of B3+in B-doped TiO2 samples, forming a possible chemical environment likeTi-O-B. The higher UV-visible light photocatalytic activity of co-doped TiO2 was attributed to the doped boron, which lowered the band gap and resulted in a localized crystal deformation. The doping of B and S enhanced the surface acidity and visible light absorption ability of TiO2. Photocatalytic activity of TiO2-B-S was enhanced due to the synergistic effect of B and S.

Key words: boron, sulfur, co-doping, titania, ultraviolet-visible photocatalytic activity, methyl orange, degradation