Construction Of Double Z-scheme V₂O₅/FeVO₄/Fe₂O₃ Composite Photocatalyst And Study On Photocatalytic Activity

Water pollution in our country has always been one of the important environmental problems concerned by the public.Due to the large discharge of medical and pharmaceutical wastewater,and the incomplete absorption of organisms,a large number of antibiotic pollutants are discharged directly or indirectly into the water body.The antibiotic pollutants in the environment will lead to the emergence of more resistant bacteria and resistance genes in natural water bodies,resulting in the disturbance of the microbial system in the natural environment.At the same time,its potential carcinogenic,teratogenic,mutagenic risk,will also have a serious harm to human society.Therefore,the removal of antibiotic pollutants in water has become an urgent problem.In recent years,photocatalytic technology has caught increasing attention of more researchers owing to its environmental-friendliness,economy and high-efficiency.However,most efforts of studies are aimed at the preparation and photocatalytic degradation of Z-scheme photocatalysts,and the problems of narrow light absorption width,high electron-hole recombination efficiency and low efficiency of Z-scheme synthesis have not been well solved.Therefore,in this study,a ternary double Z-scheme V₂O₅/FeVO₄/Fe₂O₃ composite photocatalytic system was prepared by in-situ synthesis and applied in the photocatalytic degradation of organic pollutants.In this study,a double Z-scheme composite photocatalyst was prepared by in-situ synthesis,and the photocatalytic degradation experiments were carried out under visible light irradiation with NFX,as the target contaminant.The photocatalytic activity of V₂O₅/FeVO₄,Fe₂O₃/FeVO₄ and V₂O₅/FeVO₄/Fe₂O₃ were compared.The effects of photocatalyst calcination temperature and time,catalyst particle proportion,initial concentration and catalyst dosage on the photocatalytic degradation of NFX were investigated.The degradation ability of different pollutants and the reusability of V₂O₅/FeVO₄/Fe₂O₃ composite photocatalysts were investigated.The mechanism of catalytic degradation of organic pollutants using the ternary double Z-scheme V₂O₅/FeVO₄/Fe₂O₃ composite photocatalytic system was also proposed.The results show that the double Z-scheme V₂O₅/FeVO₄/Fe₂O₃ composite photocatalytic system can be constructed effectively adopting in-situ synthesis.Under visible light irradiation,the V₂O₅/FeVO₄/Fe₂O₃ has higher photocatalytic activity and stronger photocatalytic degradation ability to NFX solution.When the dosage of the catalyst was 1.00 g/L,and the initial concentration was 2.5 mg/L,the%degradation NFX was91.78%at visible light irradiation for 180 min.In addition,in this study,the degradation ability of V₂O₅/FeVO₄/Fe₂O₃ for different organic pollutants was compared.The results showed that the composite photocatalyst had certain degradation ability for five different organic pollutants,and the sequence of%degradation is listed:AO>MB>CV>TC>NFX.Also,the V₂O₅/FeVO₄/Fe₂O₃ has good visible-light photocatalytic stability and reusability.In the process of photocatalytic degradation of organic pollutant can produce a large number of h⁺,·OH and·O₂^-.Thus,the double Z-scheme V₂O₅/FeVO₄/Fe₂O₃ composite photocatalytic system has good photocatalytic activity under visible light irradiation and has potential applications in the field of photocatalytic degradation of organic pollutants.