基于光催化水裂解制氢新型金属-TiO2结构设计、强相互作用和界面活性位探究

目前金属-TiO2光催化制氢依然缺乏新颖结构与独特功能催化材料，且与金属-载体强相互作用、界面活性位的关系尚不清楚。为此本项目拟构建新型核壳空心球结构Au(CoOx)/TiO2/Pt，系统考察金属尺寸、分散位置、状态和TiO2表面化学对金属-载体强相互作用的影响，以实现能级与界面匹配且可见光响应的高效制氢材料；结合先进的电子显微（STEM）、原位能谱（XPS、EPR）和原位红外探针分子吸附表征手段探究金属-载体之间相互作用方式（嵌入式、电子式、键合式），以期揭示相互作用-界面-性能之间构效关系；以气固相水分子裂解为模型反应，结合原位FTIR、EPR和瞬态光谱等技术重点探究金属界面活性位、水分子在表面吸附、活化和转化过程，分析光生电子在界面上的扩散、迁移路径，阐明金属-TiO2界面活性位在水裂解过程中起到的作用。项目实施将对开发新功能材料有良好的指导作用，为光催化制氢的工业应用打下理论基础。

At present metal-TiO2 photocatalytic hydrogen production still lacks catalytic materials with novel structures and unique functions. At the same time the relationship with metal-carrier strong interaction and the interfacial active sites is still unclear. Towards this hurdle, this proposal will focus on three aspects: (1) construct new core-shell hollow spheres structured Au(CoOx)/TiO2/Pt and investigate the relationship of metal-support interaction with metal size, dispersion, location, state and TiO2 surface chemistry systematically. It is aimed to engineer a nanostructure with visible light response for efficient H2 production; (2) combine advanced microscopic (e.g., STEM), in situ X-ray spectroscopic (e.g., XPS, EPR) and in situ FTIR probe molecule adsorption techniques to investigate how metal species interact with TiO2 (chemical bonding, embedded within support, or electronic adhesion). The goal is to understand the relationship between metal-support interaction, interface and performance, and clarify the role of metal-support interaction in water splitting; (3) using gas-solid phase water splitting to H2 as a model reaction, we will investigate the interfacial sites of metal-TiO2 and track the adsorption, activation, and conversion of H2O molecule on the photocatalyst interface by in situ FTIR and EPR. We also combine transparent spectroscopies and electrochemical analysis methods to study the transfer of photo-excited electrons on the metal-support interface. Hence, this proposal can provide guidelines in developing new functional materials and lay a good foundation for the industrial application of photocatalytic H2 evolution.