超薄铋基氧化物/碳纤维三维复合材料组成、结构调控及其光催化性能研究

印染废水的处理一直都是工业废水处理的难点，本项目围绕BiOX(X=Cl、Br、I)可见光催化剂在处理印染废水时面临的光催化效率低、难以回收利用等关键科学问题，通过构筑超薄二维结构，提高其对可见光的捕获能力，并为光催化反应提供更多的活性位点；通过与Bi2O3、Bi2S3等窄禁带半导体材料复合形成异质结，拓宽其光谱响应范围，提高光生电子-空穴的分离效率。为解决粉末光催化剂易团聚、固液分离难、不易回收利用等问题，将铋基氧化物负载在煤基活性碳纤维上，利用碳纤维较大的比表面积和发达的孔隙结构吸附聚集污染物，同时使催化剂暴露出更多的催化活性位点。通过本项目的研究，建立光催化效率高、性能稳定、易回收利用等优点的超薄铋基氧化物/碳纤维三维复合材料的制备方法；研究微观结构、能带结构、暴露晶面、异质结界面对光生电子-空穴分离、转移的影响，阐明有机污染物的光降解机理，为印染废水的处理提供新新思路和新途径。

The treatment of printing and dyeing wastewater is always difficulty in industrial wastewater treatment. This project focuses on the key scientific problems faced by visible-light-driven photocatalyst BiOX (X=Cl, Br, I) in the treatment of printing and dyeing wastewater, such as low photocatalytic efficiency and difficult to recycle. By constructing ultrathin two-dimensional structure, it can improve the ability of BiOCl to capture visible light and provide more active sites for photocatalytic reaction. The heterojunction is formed by combining BiOX with narrow band gap semiconductors such as Bi2O3 and Bi2S3 to broaden the spectral response range and improve the separation efficiency of the photoinduced electron-hole pairs. Bismuth-based oxide will be loaded on coal-based activated carbon fiber to solve the problems of easy agglomeration, difficult separation, and low recycling rate of the powder photocatalyst. Furthermore, the larger specific surface area and developed pore structure of carbon fiber are used to absorb and collect pollutants, and more active sites are exposed at the catalyst surface. The preparation method of ultrathin bismuth-based oxide/carbon fiber three-dimensional composites the advantages of high photocatalytic efficiency, stable performance and easy recycling will be established through the implementation of this project.The influence of microstructure, energy band structure, exposed crystal surface and heterojunction interface on the separation and transfer of photogenerated electrons and holes are studied, and the mechanism of organic pollutant degradation on the catalyst surface will be elucidated, which provide a new way for the treatment of printing and dyeing wastewater.