| As industrialisation accelerates around the world,the water environment and ecosystems are threatened by a variety of harmful pollutants and we should pay more attention to these issues.Heavy metals(Cr(VI))and organic compounds(BPA)are two typical harmful pollutants in the water environment.The removal of heavy metals and organic compounds is therefore an urgent research topic that needs to be addressed.Photocatalysis has been widely considered as one of the green technologies for environmental clean-up due to its simplicity of manufacture,good reusability,high efficiency and low cost.However,most photocatalysts are powder materials and photocatalysts are not easily separated from water after use,and,nanoscale materials may have a risk of nanotoxicity to the aqueous environment,which may have harmful effects on humans and ecosystems.There is a need to explore an excellent substrate to hold them in place.One of the most promising materials,Carbon Fiber Cloth,has received a lot of attention from the scientific community because of its very good electrical conductivity,flexibility and mechanical properties.The thesis focuses on the following:(1)Hollow spherical W18O49 nanocatalysts were prepared by autoclave,and then ZnIn2S4 was homogeneously grown on the surface of W18O49 nanocatalysts bylow-temperature water bath method to form a kind of W18O49@ZnIn2S4 heterojunction with core-shell flower spherical structure.The crystalline structure,morphological characteristics,and light absorption range of the nanocatalysts were analyzed by some common characterizations.Bisphenol A and hexavalent chromium(Cr(VI))were used as the target pollutants,and the effects on photocatalytic efficiency were studied and analyzed by adjusting a series of factors such as different catalysts,initial pH values,initial concentrations of pollutants,different light sources,and different amounts of catalysts.On this basis,further studies were carried out using free radical trapping experiments.the successful preparation of W18O49@ZnIn2S4 floral spherical structure with increased floral lamellar structure led to an increase in the surface area of the composite heterojunction,which was beneficial to the adsorption of pollutants.The degradation rates of 90.10%and 98.00%could be achieved for BPA and Cr(Ⅵ)hexavalent chromium,respectively.The formation of the flower-like structure promoted the rapid transfer of carriers,while the core-shell structure increased the interfacial area and active sites.(2)The spherical W18O49 nanocatalysts were grown in situ on carbon cloth using a hydrothermal method,and then the W18O49@Znln2S4/CC nanocatalysts were prepared by homogeneous loading of ZnIn2S4 onto the W18O49/CC nanocatalysts by a low-temperature water bath method.The W18O49@Znln2S4/CC nanocatalysts were analyzed by means of characterization for their crystalline phase structure,morphology characteristics,surface elemental morphology,light absorption,photothermal analysis,and photoelectric analysis.The effects on photocatalytic efficiency were investigated by adjusting light intensity,different catalysts,initial concentration,initial pH,and number of catalyst cycles using bisphenol A and hexavalent chromium Cr(VI)as target pollutants.the hollow structure of W18O49@Znln2S4/CC improved the light utilization,while the core-shell structure increased the interfacial area and the number of active sites.The degradation rates of 98.20%and 100.00%could be achieved for bisphenol A and Cr(Ⅵ)hexavalent chromium,respectively.In addition,the oxygen vacancy in W18O49 has ligated unsaturated sites and unpaired electrons,which can lower the reaction energy barrier and promote molecular activation.Its easy recovery and high stability imply potential practical applications and provide an effective strategy for the development of a new efficient catalyst. |
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