与氯酚高亲和金属酞菁的设计合成及其与窄带隙半导体共敏化TiO2 NTs 仿生催化降解氯酚类污染物的研究

Chlorophenols are serious environmental pollutants. They are difficult to be completely mineralized. Both TiO2 nanotube arrays (TiO2 NTs) sensitized with narrow band gap compounds and heterogeneous photocatalytic systems loading with metal phthalocyanines have their own advancement in the mineralization of them. However, both the systems suffer the same weakness of low adsorption to chlorophenal. The aim of this project is to combine the advantagement of the two systems and at the same time improve the adsorption capacity of chlorophenol. In this project, metal phthalocyanines highly adopted to chlorophenols will be designed and synthesized. Then they will be coloaded with the narrow band gad compounds to TiO2 NTs. The loading method will be studied in detail and the the best technology will be choosed. After being applied in the photodegradation of 4-chlorophenl, the intermediats, and the final products will be carefully detected. The active spiecies will be detected and scanvenged to understand the dechloronation and cyclo-opening mechanism of chlorophenols. Based on this study, different metal phthalocyanines and narrow band gap compounds combination will be designed and applied in the degradatioin of other chlorophenols. Highly efficient complicated systems for complete mineralization of chlorophenols will be screened. Coloading highly chlorophenol adsopted metal phthalocyanines and narrow band gad compounds on TiO2 NTs has not been reported. The study will explore a new technology in completely mineralization of chlorophenols.

氯酚类污染物危害大，矿化难。窄带隙半导体敏化的TiO2纳米管阵列（TiO2 NTs）及负载金属酞菁仿生酶的光催化体系在氯酚矿化中各有优势。但也存在对脂溶性氯酚亲和性差的共同弱点。本项目的目的就是联合两个体系的各自优势，通过设计合成与氯酚高亲和的金属酞菁解决对氯酚亲和性差的弱点。项目将对催化剂共敏化方法详细考察，研究最佳负载技术。并以4-氯酚为模型化合物，通过对降解过程中间体、最终产物的分析；对活性物种的检测、捕捉，提出二者协同作用机制，理解氯酚脱氯，开环机理。在此基础上，指导设计并考察不同金属酞菁及窄带隙半导体组合，最终找到能最有效矿化氯酚的复合体系,深入理解氯酚矿化机制。金属酞菁及窄带隙半导体协同TiO2 NTs仿生催化降解氯酚，相关研究在国内外还属空白，研究结果将为氯酚深度净化提供新的技术途径。

基于TiO2光催化剂的光化学催化氧化技术，是最为有望商业应用的十大废水处理技术之一。如何提高TiO2对有毒有害物质的可见光催化效率，是目前研究的重要方向之一。研究以提高TiO2对有害物质亲和能力，提高其对可见光利用为目标，设计及制备窄带隙半导体及对有害物质具有高亲和能力的有机半导体共敏化的TiO2，仔细研究其催化降解酚类有机物质过程中的活性物种及降解有机中间体，提出了其可见光催化降解机理，主要是光催化还原过程而不是光催化氧化过程。并进一步通过对CrVI的催化还原研究，进一步确认了其可见光催化还原过程。