碳点负载钌基双金属纳米晶的可控制备和电解水产氢性质研究

The electrocatalytic splitting of water via the hydrogen evolution reaction (HER) is an important process for highly efficient energy conversion by hydrogen production, and the key problem is to obtain a low-cost, high-efficiency and stable catalyst. In this proposal, RuM@CDs (M is Fe3+, Co2+, Ni2+ etc) catalysts will be prepared by heat treatment methods through assembling Ru3+, MX+ with carbon dots, which is easy to prepare, modify, doping and rich in resources. The defect of CDs and the morphology, particle size, dispersion of RuM@CDs will be tailored by controlling the crystallinity of CDs, the metal loading, the ratio of Ru to M, hetero atom type and content and optimizing the technological parameter during the preparation process. The crystallinity, hetero atom type and content, metal loading, Ru/M ratio, preparation process parameters, etc. will be optimized. The process of cross-linking carbonization about CDs, nucleation, growth of RuM nanocrystalline will be studied by in-situ characterization to expose the influence of the intrinsic mechanism about the microstructure of RuM@CDs. Thereafter, RuM@CDs will be tested for the hydrogen product of electrocatalytic splitting of water. The partial atomic and electronic structure of Ru-M, RuM-CDs, RuM-water and CDs-water interfaces will be studied by in-situ characterization and theoretical calculations to clear reaction mechanism, thereby clarifying the structure-activity relationship at the atoms and molecular level. Finally, the regulation of CDs and RuM to enhance catalytic activity will be proposed. The achievement of this proposal would provide the idea and implications for the reasonable design of the highly active metal-carbon based catalysts.

电解水制氢（HER）是氢能的高效来源之一，其关键在于获得低成本、高效、稳定的催化剂。本项目拟以易制备、易修饰、易掺杂、资源丰富的碳点（CDs）为构筑基元，与Ru3+，M（M为Fe3+、Co2+、Ni2+等廉价金属离子）进行组装，热处理制备CDs负载RuM双金属纳米晶催化剂（RuM@CDs）；优化CDs结晶性及杂原子种类和含量、金属负载量及Ru/M比例、制备工艺参数等，调控RuM的形貌、尺度、分散性和CDs的化学环境、缺陷等，采用原位技术表征RuM纳米晶的成核、生长和CDs的交联碳化，揭示影响RuM@CDs微观结构的内在机制；测试RuM@CDs的HER性能，采用原位表征和理论计算解析Ru-M、RuM-CDs、RuM-水和CDs-水界面的局域原子和电子结构，明确反应历程，澄清原子、分子水平上的构效关系，提出增强催化活性的有效方法。为理性设计高效碳-金属复合HER催化剂提供新思路和理论指导。

电解水制氢（HER）是氢能的高效来源之一，其关键在于获得低成本、高效、稳定的催化剂。本课题通过合理且科学地选取小分子前体，通过自下而上的策略，获得多种具有不同结构的高质量碳点（CDs）；同时通过电子透射显微镜、原子力显微镜，拉曼光谱、荧光光谱仪等对所得碳点的结构和性能进行表征，优化实验条件，实现具有优异电子传输性能的高结晶碳点的可控制备。本项目开发了多种以碳点为载体的碳点基电催化剂并用于HER，实现了高效率、高稳定的电解水。考察了碳点与金属之间的相互作用以及构效关系，发现并提出了一种基于CDs自组装和交联拼接的CDs基电催化剂的生成机制。通过原位红外，球差透射电镜和同步辐射X射线吸收光谱，辰华电化学工作站等表征分析手段，深入研究了CDs基电催化剂的组成，结构和催化性能，同时研究了不同热处理条件和多种金属间的协同效应对CDs基电催化剂的析氢影响，构建了一种具有普适性的CDs基电催化剂的合成和优化策略。