负载有钴单原子位点的二维碳氮骨架材料：可控制备及其电解水产氢性能研究

This project is focused on the design and fabrication of catalyst materials with high stability and efficiency for hydrogen evolution reaction (HER). We investigate the influences of active cites and electronic transport capacity of support materials on the catalytic performance. In order to realize the synergy effect of active materials and support materials, we design a series of materials with single atomic cobalt sites based two-dimensional CN frameworks based on the relationship of structures and properties. For this project, we firstly investigate the table structure of single atomic cobalt sites on the two-dimensional CN frameworks. Then, we design materials with various concentrations of atomic cobalt sites and different degrees of phosphorization. Next, we evaluate the properties of materials by catalytic process of HER. Based on the catalytic performance, we optimize the structure and composition of materials. By the electrochemical testing, together with the first-principle calculations, we investigate the reaction mechanism on the materials surface and reveal the influence of active atomic sites and electron transport capacity of supports on the properties of materials. This project will establish foundation to design and prepare single atomic cobalt sites based materials with high stability and efficiency in broad applications.

本项目以设计及制备高活性，高稳定性的电催化产氢材料为目标，依据“结构-性能”构效关系，从增加反应活性位点和增强载体电子输运能力出发，设计并制备出一类负载有钴单原子位点的二维碳氮骨架材料，实现活性材料与载体材料之间的有效协同作用，提高材料的催化活性和稳定性。本项目首先研究碳氮骨架稳定钴单原子位点的机制。其次，通过调控钴单原子位点的负载浓度及碳氮骨架材料的磷化程度，最终获得不同组分的材料。以电催化产氢反应来评价材料性能，反馈对材料组分的优化。通过电化学测试方法，并结合第一性原理计算来研究材料表面的电化学反应过程，揭示单原子活性位点及载体电子输运能力对材料催化性能的影响。为高效，稳定的钴单原子位点催化材料的设计与制备奠定基础。

本项目以理性设计与精准制备高效金属单原子产氢催化材料为研究目标，通过调控材料的微观形貌结构以及表界面多级次微纳结构来强化催化反应过程中的物质输运和表面反应，以实现高效的催化反应过程。项目组通过调节金属前驱体摩尔浓度制备钴（Co）单原子催化材料；进一步通过引入磷源来调节Co单原子活性位点的配位环境，以构建具有异原子配位环境的单原子活性中心来平衡优化催化反应过程中离子/分子的吸、脱附难易程度；通过在低维载体表面引入丰富的缺陷位点以实现对高浓度金属单原子的锚定与稳定；基于材料电催化产氢性能反馈调节催化材料的设计制备，以获得高效的电催化产氢性能；并结合理论计算研究和同步辐射技术探明单原子活性位点局域原子结构和电子结构，揭示材料结构与产氢性能之间的“构-效”关系。此外，基于强化物质（能量）传输和表面反应，项目组围绕具有多级次微纳结构的中空多壳层材料开展了一些研究工作，来作为对高效单原子电催化产氢材料工作的补充，为后续高效光电协同催化材料的理性设计与精准制备积累研究基础。