类石墨结构MoS2/g-C3N4催化剂可见光分解水制氢及作用机制研究

Photocatalytic water splitting for hydrogen production using solar energy is one of the ideal ways to achieve the clean energy, and the optimizing of the composition and structure of the cocatalyst is one of important approaches to improving the efficiency of hydrogen production. Based on the similarity in their layered structure of MoS2 and g-C3N4, together with the high activity of hydrogen evolution catalyzed by MoS2, we propose to use MoS2 as a cocatalyst and construct MoS2/g-C3N4 ultra-thin surface junction catalyst. The optimization of the catalyst preparation, the chemical composition, optical property, surface state of the catalysts as well as the local and electronic structure of the active sites, together with the separation and interfacial migration of the photo-generated carriers will be examined in details. Combined with the hydrogen production performance, we will explore the interaction and matching between the layered cocatalyst and layered photocatalyst and study the relationship between structure and performance, thus clarify the mechanism and the regulation law in water splitting into hydrogen over MoS2/g-C3N4. This will provide the experimental basis and theoretical guidance and for the design and preparation of other photocatalysts.It is of great significance to improve the efficiency of photocatalytic water splitting into hydrogen and promote the practical application in the direct conversion of solar to chemical energy.

利用太阳能光催化分解水制氢是获取清洁能源的理想手段之一，而优化助催化剂的组成和结构是提高其制氢效率的重要途径之一。针对纯石墨相氮化碳（g-C3N4）分解水制氢的光量子效率低，基于层状化合物MoS2具有良好的催化析氢能力，该项目提出以MoS2作为g-C3N4的助催化剂，利用它们结构相似性来构筑MoS2/g-C3N4超薄表面结催化剂的新思路，将详细研究催化剂的优化制备、化学组成、光吸收特性、表面状态、活性中心以及光生载流子的分离和界面转移；探讨MoS2和g-C3N4之间的相互作用和匹配问题，结合光解水制氢性能的评价结果，揭示催化剂的构-效关系，进而阐明MoS2/g-C3N4光催化分解水制氢的作用机制，为其它光催化剂的设计和制备提供实验依据和理论指导。该研究对提高光催化分解水制氢的效率和促进太阳能直接转化为化学能的实际应用都具有重大意义。

利用太阳能光催化分解水制氢是获取清洁能源的理想手段之一，而优化助催化剂的组成和结构是提高其制氢效率的重要途径之一。针对纯石墨相氮化碳（g-C3N4）分解水制氢的光量子效率低，基于层状化合物MoS2具有良好的催化析氢能力，该项目提出了MoS2作为g-C3N4 的助催化剂，利用它们结构相似性构筑了MoS2/g-C3N4 超薄表面结催化剂，详细研究了催化剂的优化制备、化学组成、光吸收特性、表面状态、活性中心以及光生载流子的分离和界面转移；探讨了MoS2和g-C3N4之间的相互作用和匹配问题。结合光解水制氢性能的评价结果，揭示了催化剂的构-效关系，阐明了MoS2/g-C3N4光催化分解水制氢的作用机制。另外，尝试了将其它过渡金属硫化物作为助催化剂负载于g-C3N4上，研究了过渡金属硫化物/ g-C3N4在可见光分解水产氢中的应用。该研究不仅为构筑二维层状光催化剂的设计和制备提供实验依据和理论指导。同时，采用储量丰富且价格低廉的过渡金属硫化物取代贵金属作为助催化剂，促进光催化技术的推广应用。