二维单分子层材料的制备、表界面设计及光催化产氢机制研究

In view of the poor efficiency and unclear mechanism of heterogeneous photocatalytic H2 evolution reaction, this proposal will focus on photocatalytic H2 evolution over 2D monolayer materials. A controllable method for the preparation of 2D monolayer materials will be explored and established by a top-down or down-top approach. According to the features of photocatalytic H2 evolution reaction, surface engineering (including cleaning of surface atoms, induction of lattice defects and construction of surface junctions) of monolayer nanosheets will be performed for further constructing photocatalyst with a highly efficient activity, via crystal engineering, supermolecular chemistry and self-assemble strategy. The effects of constitution, crystal structure, electronic structure, surface/interface structure of photocatalyst on charge kinetics and photocatalytic activities will be investigated in detail. Combined with quantum chemical calculation, we will unravel the charge behaviors and photocatalytic H2 evolution mechanism of photocatalyst at the molecular level, as well as provide a possible theory for the guidance of designing photocatalyst with high quantum efficiency.

针对异相光催化产氢效率低和催化机制不明确等问题，本项目拟开展二维单分子层材料光催化产氢的研究。探索和建立“自上而下”或“自下而上”可控制备单分子层纳米片的方法。针对光催化产氢反应的特点，运用晶体工程学、超分子化学原理、自组装等策略调控单分子层纳米片的表面（“清洗”表面原子、诱导晶格缺陷、构建表面结），进而构筑高效产氢光催化剂。探索光催化剂的组成、晶体结构、电子结构、表界面结构对光催化剂的载流子动力学和产氢活性的影响。结合量子化学计算，从分子水平上阐明光催化剂的载流子行为和产氢机制，为构筑高效产氢光催化剂提供可能的理论。

光催化制氢被认为是一种绿色、有效、性价比高的制氢方法，在解决环境与能源问题中有着巨大的潜在应用。二维纳米片材料因其独特的晶体学结构在光催化产氢催化剂的应用中具有独特的优势。本项目基于晶体工程学，通过“自上而下”的策略合成了HNb3O8、HSr2Nb3O10、WO3、ZnS、C3N4二维纳米片，也利用“自下而上”的策略合成了CdS和SnS2二维纳米片。而后基于构-效关系，通过合理的调控二维纳米片材料的表界面，设计了具有高效光催化产氢性能的光催化剂，并探索和总结了具有不同表面性能的纳米片材料的表面调控规律，揭示其组成、表面性质、晶体结构和电子能级结构对光催化剂的载流子动力学和产氢活性的影响，为开发高效二维纳米片基产氢光催化剂提供实验基础。