| The development of bromate removal technology is urgent,since bromate,disinfection by-product in drinking water,has been classified as potential carcinogen(Group 2B)by the International Agency for the Research on Cancer.Photocatalytic removal technology has become a research hotspot due to its high efficiency and stability.In this study,two series of F modified TiO2 photocatalysts with {001} crystal surface were prepared by one step hydrothermal method:F and Graphene oxide codoped TiO2(FGT),F and Fe codoped TiO2(FFeT).They were used to study the photocatalytic removal of BrO3-under UV and visible light,respectively.Combining with Transmission electron microscopy,Electron paramagnetic resonance and UV-vis diffuse reflectance spectroscopy,based on morphology,structure and optical properties of the photocatalyst,the effectiveness and mechanism of photocatalytic removal of bromate were discussed.Meanwhile,the effects of conventional anions,humic acid on bromate Photocatalytic removal by FGT were studied,and the removal efficiency in the actual water were investigated.Over 90%of bromate could be removed with a 0.05 g/L dosage of F and Graphene oxide(GO)co-doped TiO2 composite in 15 min under UV irradiation at an intensity of 26?W/cm2 and pH of 5.2.The results show that the activity of the catalyst is inhibited by the competitive adsorption and the solution pH in the actual water,but the overall removal effect is still satisfactory.The bromate solution of 100?g/L was thoroughly removed with 0.5 g/L dosage of F and Fe-codoped TiO2 composite within 1 hour under visible light.The high activity of the FGT photocatalyst is significantly enhanced attributed to the doping of GO,because of its conductive properties improving the migration velocity of photoinduced electron-hole pairs in TiO2.The light response range of FFeT series material was greatly broadens and band gap was narrowed from 2.92 to 2.55 by Fe doping,which has prominent reactivity in visible light.And in both of them,F as a morphology control agent,successfully induced the formation of {001} crystal surface to promote the migration of photogenerated electron hole pairs and effectively inhibit their complex.In addition,the modification effect of catalyst is further improved by the synergistic effects of two elements Co-doping,which has better activity and stability,providing a theoretical basis for its application in the removal of bromate. |
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