磁性可见光双驱动微马达的可控构筑及对水体细菌杀灭的增强机制研究

水体中存在的大量致病微生物严重威胁人类健康，传统半导体光催化剂应用于水体细菌杀灭仍然存在两个关键瓶颈问题：靶向效率低且需要宏观搅拌才能与微观细菌接触。本项目以具有卓越可见光光催化性能的Fe-BiOM（M=I，Br）微球为基底，通过化学还原法可控构筑具有Janus结构的磁性可见光双驱动Fe-BiOM/Au微马达，同时，以Au作为连接单元，修饰具有高效识别捕获细菌的生物分子；以水体中常见的病原微生物 E. coli 及 S. aureus 作为模式菌来评价其杀菌效果；探究微马达的组成、结构、性能之间的构效关系；深入研究多重改性手段对磁性可见光双驱动微马达的光吸收、光生载流子分离效率、能带结构、运动特点、对细菌的特异性识别-捕获-杀灭等过程的协同作用，挖掘其关键性、实质性的对水体细菌光催化杀灭增强机制。该研究可为开发新型光催化材料提供理论与实验基础，为水体病原微生物污染治理提供新思路。

The microbial contamination of water poses great threat to human health. However, inactivation of the waterborne pathogens by using traditional photocatalysts are severely hampered by two major bottleneck issues: i) the low bacteria-targeting efficiency; ii) the added macro-stirring becomes necessary to initiate the microscopic contact between bacteria and the catalyst in these systems. This project creatively proposes a novel research idea to improve the photocatalytic inactivation activity towards bacteria in water by controllable construction of the dual magnetic/visible light driven micromotors based on the Fe-BiOM (M=I，Br) microsphere with excellent visible light photocatalytic activity. Meanwhile, the micromotor was further modified with the bioreceptors that can highly selective capture bacteria via the adsorption of mercapto self-assembled monolayers (SAMs) on Au surface. Then, the photocatalytic antibacterial activity of the micromotors will be systematically investigated against the typical pathogenic microorganisms such as E. coli and S. aureus in water. The structure-activity relationships between composition-structure-catalytic performance of the micromotors will also be explored. Finally, the effect of multi-strategy on photoelectric characteristics of the micromotors，including the visible-light absorption properties, the separation of photogenerated electron–hole pairs and the band structure, the motion properties and the specific recognition-capture-killing of bacteria will be deeply investigated, revealing its critical and substantial effects attributed to the enhanced mechanism of bacterial killing. Collectively, this project will provide theoretical and experimental foundation for designing novel photocatalyst, and give new insights into controlling pathogenic microorganism pollution in water.