g-C3N4基直接Z-型光催化制氢材料的构筑

Structure design and controllable fabrication of highly visible-light active photocatalytic materials are one of hotspots of photocatalytic investigations. This project will mainly focus on the controllable preparation of novel direct Z-scheme C3N4-based composite materials by hydrothermal method and sol-gel method, using the advantages of Z-photocataltic system including improved the separation efficiency between photogenerated electron and hole, and strong oxidation and reduction ability. The relation between the composite, morphology, interface microstructrue of the composites and photocatalytic properties will be investigated. The influence of interface character on the behavior of photogenerated carriers and photocatalytic activities will be discussed. The microscopic mechanisms of interface interaction and interface carriers transfer and the possible Z-scheme mechanism in enhancing photocatalytic H2-produciton activity will be carefully discussed. This investigation will provide new insight into the fabrication of Z-scheme photocatalysts and reveal the rule of Z-scheme carrier transfer and the mechanism in enhancing photocatalytic activities. The implementation of this project will provide both practical and theoretical guidance for the development of highly efficient, low cost and environmental-friendly photocatalyst materials for visible-light-driven hydrogen production, which is of great significance for the promotion of green and sustainable solar energy conversion technologies.

高活性可见光响应光催化材料的结构设计与可控制备是光催化领域的前沿和热点研究问题之一。本项目拟利用Z-型光催化系统高的光生电子-空穴对分离效率和强的氧化还原能力等独特优势，综合运用水热法、溶胶凝胶法等方法，制备无电子导体的C3N4基直接Z型可见光光催化材料，研究C3N4含量，复合光催化剂的组成、形貌、界面微结构与光催化产氢活性之间的构效关系；并详细分析光催化体系中界面特性对光生电荷行为和光催化活性的影响，结合光催化稳定性研究，揭示界面耦合作用与光生载流子界面迁移微观机制以及Z-型结构增强光催化活性的内在机理。通过本项目的研究，可以丰富Z-型光催化材料的制备方法，揭示光催化产氢过程中Z-型载流子传递的规律和增强活性的机理。本项目的实施可以为开发高效、稳定、价格低廉的环境友好型光解水材料提供重要的理论和实验依据，对推动绿色可持续太阳能转化技术而言具有重大研究意义。

本项目从提高光催化材料的光活性、量子转换效率和材料的稳定性出发，设计和制备新型的C3N4 基直接Z-型光催化材料，揭示光催化产氢过程中能量转换与直接Z-型光催化材料可见光光催化性能之间的关系。首先：选择不同的反应物等进行前驱体的共聚改性，采用不同模板制备出具有形貌、结构可控的石墨相氮化碳纳米材料（如纳米管、纳米纤维、介孔氮化碳、中空氮化碳等；通过水热、超声剥离、非金属/金属掺杂、表面酸处理等技术，制备出具带隙可调、高比表面积、高可见光利用率的C3N4 光催化材料；其次，通过共沉淀、水热和微波水热等方法可控制备具有高可见光活性和高稳定性C3N4 基直接Z-型光催化材料，研究和考察Z-型复合材料的微结构、组装基元、界面耦合作用与光催化性能之间的关系，复合光催化体系中的作用以及各组元之间的相互作用机制以及界面结构与光催化活性之间的规律；通过多种表征手段和理论计算相结合，揭示界面结构、Z-型载流子迁移途径与产氢性能的变化规律，揭示复合光催化成其产氢增强机理；最后，拓展了C3N4 基异质结复合材料在光催化产氧、降解有机污染物等方面的应用，开发了基于硫化物，氧化物半导体高性能产氢材料。本项目的实施可以为开发高效、稳定、价格低廉的环境友好型光解水材料提供重要的理论和实验依据，对推动绿色可持续太阳能转化技术而言.具有重大研究意义。