石墨氮化碳层间/表面结构调控及活性氧增强灭活水中病原微生物的机理研究

严格控制再生水利用过程中的病原微生物，是亟待解决的水安全问题之一。光催化作为一种新型水消毒技术具备经济、安全、清洁等优点，限制其实际应用的关键因素是光催化材料活性。本项目拟以石墨相氮化碳（g-C3N4）聚合物半导体构建可见光响应下的高效光催化灭活体系，通过g-C3N4层间掺杂与表面官能团的原位协同调控策略，增强体相光生电荷分离、表/界面电荷转移与活性氧（ROS）生成，提高ROS作用下的病原体灭活效率；探明复杂水环境条件下，不同环境因素对光催化灭活病原菌的促进或抑制效应，构建特征因子与灭活效率模型关系；结合理论计算与实验深入理解g-C3N4能带结构与表面微结构，对增强分子氧活化能力和诱导活性氧生成途径的内在规律，澄清体系中活性氧胁迫下抗菌活性与细胞应激响应，阐明g-C3N4结构优化与光催化作用下病原体细胞结构破坏与死亡的机制，为推进再生水利用中光催化消毒技术的应用和发展提供基础理论依据。

It is one of the urgent water security issues for strictly controlling the pathogenic microorganisms in the reclaimed water. As a novel water disinfection technology, photocatalysis possesses many advantages, such as low-cost, safety and clean, while the key factor limiting for its practical application is the photocatalytic activity. This project will construct a highly efficient visible light-response photocatalytic disinfection system based on the polymer semiconductor g-C3N4. And through the in-situ coordinating strategy for the g-C3N4 interlayer doping and surface functional groups, the bulk charge separation, interface charge transfer and interface reactive oxygen species (ROS) generation could be enhanced, and resulting in the improving inactivated pathogens under the ROS mechanism. The effects of different environmental factors on photocatalytic inactivation in the complex water environment will be analyzed, as well as the model relationship between environmental factors and inactivation efficiency. Combined with theoretical calculation and experiments, it can be deeply understanding that the energy band structure and surface microstructure of g-C3N4 on enhancing oxygen activation ability and inducing ROS generation pathway. It can be clarified that the antibacterial activity and stress response of cells inducing by reactive oxygen species in the photocatalytic system. The mechanism of destruction and death of pathogen cell in photocatalysis by the modified g-C3N4 will be analyzed. Our results will provide a basic theoretical basis for the development and application of photocatalytic disinfection technology in the reclaimed water reusing.