水中难降解有机污染物的吸附富集-光电催化协同去除研究

The organic pollutants, one of the main contaminants in water at present, have a direct impact on water quality. The removal of organic pollutants in water is one of the key contents of research on environmental pollutants controlling. This subject focus on decontaminating the low concentration of organic pollutants in water by adsorption concerted and catalytic degradation to mineralize the organic pollutants completely via graphene-photocatalyst hybrid hydrogel. The graphene-photocatalyst hybrid hydrogel with high specific surface area and network structure can be obtained via the hybrid of graphene oxide and the photocatalyst and the controllable reduction and crosslinking of the graphene oxide hybrid layer. The controlling rules of the specific surface area and network structure of the hybrid hydrogel and regulating factors of the surface groups will be revealed. The adsorption law, adsorption mechanism and adsorption kinetics of typical pollutants by the hybrid hydrogel will be investigated. The mechanism and regularity of adsorption concerted and in situ photocatalytic degradation by the hybrid hydrogel will be revealed. The intrinsic relationship between the reduction of graphene oxide and the regularity of adsorption and photoelectro-catalytic degradation and mineralization mechanism will be demonstrated. The new method of adsorption concerted photocatalytic degradation and mineralization of pollutants in water will be established. The project will provide new solutions to the key problems of controlling organic pollutants in water and promote the development of environmental chemistry.

水中有害有机物是目前水环境的主要污染物之一，直接影响了用水质量。水中有机污染物的去除研究也是污染物控制研究的重要内容之一。本课题拟通过石墨烯杂化光催化剂水凝胶，对水中低浓度有机污染物进行吸附富集-催化降解的协同净化，实现有机污染物的彻底矿化去除。通过氧化石墨烯与光催化剂的杂化作用及表面杂化氧化石墨烯的可控还原交联，可获得具有高比表面积、网状结构的石墨烯杂化光催化剂水凝胶；研究并揭示该复合水凝胶的高比表面积、网状结构调控规律及表面基团功能化的影响因素；揭示复合水凝胶对典型污染物的吸附规律、吸附机理及吸附动力学；揭示复合水凝胶对污染物的吸附富集与原位光催化降解的协同作用规律和机理；揭示水凝胶中氧化石墨烯的还原度与光电协同催化降解有机污染物的规律和矿化机理；建立水中有害有机污染物质的吸附富集-催化降解矿化的新方法。项目的实施为水中有机污染物控制关键问题的解决提供新思路，可促进环境化学学科的发展。

水体污染物组成复杂，通常含有有机染料、酚类污染物、抗生素、重金属离子等，对生态环境、人类健康产生巨大威胁。探索开发高效、安全、环保的水污染物处理方法对环境污染物控制具有重要意义。本项目从环境污染物降解的关键科学问题入手，开发新型光催化材料，开发污染物新型吸附富集材料，开发污染物新型吸附富集-光催化/光电催化协同降解体系，揭示其中的普遍科学规律。成功获得多种高性能、宽光谱响应的新型光催化剂，开发具有核壳结构的复合光催化剂，为进一步探索开发光电协同的污水处理体系提供基础。成功建立一系列高比表面、三维网状结构的石墨烯复合水凝胶光催化的制备方法，获得石墨烯-TiO2、石墨烯-C3N4、石墨烯-Bi2WO6、石墨烯-BiPO4等一系列结构相似、性能各异的水凝胶。成功揭示石墨烯复合水凝胶光催化剂的形成机制及其网状结构调控规律，并将其进一步广泛拓展，获得一系列基于琼脂、聚苯胺、SiO2等材料的新型凝胶光催剂，实现静态/动态体系下对于亚甲基蓝、甲基橙、苯酚、双酚A等有机环境污染物的高效吸附富集-光催化协同降解。成功揭示复合水凝胶光催化剂的吸附富集过程与原位光催化降解的协同去除机制，大比表面的三维网络结构对于水中污染物发挥吸附富集作用，有效提高光催化、光电催化处理通量。成功构筑基于g-C3N4薄膜光电极、g-C3N4/TiO2复合薄膜光电极、苝酰亚胺超分子薄膜光电极、石墨烯-TiO2复合凝胶光电极等光电催化降解体系。成功建立完整的吸附富集-光电催化降解协同处理的一体化高效去除水中难降解有机污染物、重金属离子的新方法。系统研究复合光电极表面状态、光催化剂结构、辐射光源、偏压大小等因素对催化降解性能的影响规律。成功揭示吸附富集与光电协同催化降解机理和污染物的矿化机理。本项目成功揭示吸附富集机制以及污染物去除的热力学因素和动力学过程，为环境污染物的治理提供科学依据，促进环境化学、材料化学、物理化学等多个学科进一步发展。