TiO2/FeOOH纳米复合结构晶格匹配与光化学协同作用机制

Based on the modulation of multiphase nanocomposite structure with the environsensitively photocatalytic activity,it's put forward that environment mineral materials should be mainly developed from dispersive mineral grains loading catalysts to a stable two-dimensions large size film with "multiphase ordered composite system "which has highly photochemical activity to deal with pollutants. Through regulating and assembling of multiphase composite structure of TiO2 (anatase and rutile phase)and FeOOH (goethite)in the nanometer scale with use of SAMs on quartz glass and mineral substrates, the highly active and stable composite film with photocatalytic coupling enhancement effect under visible light will be synthesized in the light of different Fe/Ti ratio and phase structure,and the lattice matching of nano-phases and their interfacial structures as well as energy bands will be investigated. In the interactional system of the multiphase film with harmful organics and heavy metal ions in aqueous solution,the coupling enhancment effect of visible light photocatalytic oxidation degradation and photochemistry removal of heavy metal ions will be studied completely. From the analyses of microstructure of the ordered composite film,interface chemistry and polyphase interfacial structure of iron and titanium oxide,the mechanism of photocatalytic coupling and photochemical synergistic effect will be carried out,and the nano-composite structure will be optimized to improve the responsiveness, removal efficiency of environment targets and stability of the film in the stimulation of visible light. It's possible to provide theoretical basis for environmental restoration and high-technology of water treatment of organic and heavy metal pollutant in the soil and water environmental system.

从调控具有环境敏感的光化学活性的多相纳米复合结构着手，提出将目前以分散型矿物颗粒负载催化剂为主的环境矿物材料发展为稳定的大尺寸二维薄膜为主的高活性"多相有序复合系统"来处理环境污染物的研究。通过单分子层自组装技术在纳米尺度上调控组装TiO2（锐钛矿和金红石相）和FeOOH（针铁矿）的多相复合结构，在基底上构建不同Fe/Ti比和矿物相结构的稳固复合层，协同产生可见光催化耦合增强效应。力图从分子识别和晶格匹配理论角度，研究低温水溶液中纳米锐钛矿、金红石相的晶相调控机制及铁钛氧化物多相界面结构的匹配生长机理；并系统研究复合结构对水溶液中有害有机物具有耦合增强的可见光催化氧化降解和重金属离子的光化学协同去除机理。从界面结构、能带和界面化学揭示光化学协同作用机制，指导优化纳米相复合结构提高其可见光激发下对环境目标物的响应性、去除率和稳定性，为土壤-水污染的环境修复与处理技术提供理论基础。

将目前主要以分散型矿物颗粒负载催化剂为主的环境矿物材料，转变为稳定的大尺寸二维薄膜为主的高活性"多相有序复合系统"。从不同方面考察其处理环境污染物效果，并探究其光化学降解机理。主要从分子识别和晶格匹配理论角度，研究低温水溶液中纳米锐钛矿、金红石相的晶相调控机制及铁钛氧化物多相界面结构的匹配生长机理；并研究复合结构对有机物溶液具有耦合增强的可见光催化氧化降解光化学协同去除机理。从界面结构、能带和界面化学揭示光化学协同作用机制。研究主要通过“分子自组装”法，在纳米尺度上调控形成TiO2（主要为锐钛矿和金红石相）和FeOOH（晶型主要为针铁矿型）的多相复合结构。在石英玻璃及矿物基底上构建具有不同Fe-Ti含量及不同的矿物相结构的稳固复合层，以模拟印染废水甲基橙、罗丹明B和模拟抗生素废水甲砜霉素溶液为光催化降解目标物，提出了局域吸附-可见光催化氧化协同作用的耦合增强效应模型。最后对光催化过程中铁钛纳米复合材料在固液界面上，由光引发的铁的多重氧化还原反应过程进行了初步研究。为进一步优化纳米相复合结构提高其可见光激发下对环境目标物的响应性、去除率和稳定性，制定水体及土壤环境修复与处理方案提供有效的理论依据。