The photocatalytic reduction of CO2 with heterodinuclear catalysts based on earth abundant metals

基于地球丰富金属的异双核催化剂光催化还原CO2

• 批准号: 403846015
• 负责人: Dr. Matthias Schwalbe
• 金额: --
• 依托单位: Department of Chemistry
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/403846015?language=en
• 关键词: photocatalytic; reduction; CO2; heterodinuclear; catalysts

Our goal is the development and in detail investigation of catalytic systems for the light-driven reduction of carbon dioxide. A major aim is to compare inter- and intramolecular systems that are based on the same combination of photosensitizer and catalyst. The photosensitizer units as well as the catalytic units will be based on non-noble metal compounds, such as chromium and molybdenum complexes in first case and iron, cobalt and nickel complexes in later case. Their catalytic performance will be determined in dependence of the used solvent, sacrificial electron donor and other relevant parameters. Photosensitizer-catalyst dyads with varying linker units are synthesized as intramolecular systems. The close vicinity of the two metal units in the intramolecular system should favor an electron transfer event towards the catalytic unit and the overall compound architecture should slow down a detrimental back electron transfer. The selective reduction of carbon dioxide to carbon monoxide, formic acid or even methane will be explored. Product selectivity should be achieved with the right choice of reaction conditions, type of catalytically active metal center and ligand architecture. The second major goal is obtaining more insight into the energy and electron transfer processes within the photocatalytic systems (inter- as well as intramolecular). Thus, extended spectroscopic studies will be performed to determine the photophysical properties, e.g. lifetime of charge-separated states, of the compounds starting from the ground state as well as from reduced species. The isolation and characterization of intermediates should add another piece to the puzzle of understanding the proceeding processes, which should lead to the proposal of a refined reaction mechanism – especially for the heterodinuclear compounds.

我们的目标是开发和详细研究用于光驱动还原二氧化碳的催化系统。一个主要目的是比较基于光敏剂和催化剂的相同组合的分子间和分子内系统。光敏剂单元以及催化单元将基于非贵金属化合物，例如在第一种情况下的铬和钼络合物以及在后一种情况下的铁、钴和镍络合物。它们的催化性能将取决于所使用的溶剂、牺牲电子供体和其他相关参数。具有不同连接基单元的光敏剂-催化剂二联体被合成为分子内系统。分子内系统中两个金属单元的紧密邻近应有利于朝向催化单元的电子转移事件，并且整体化合物结构应减缓有害的反向电子转移。将探索将二氧化碳选择性还原为一氧化碳、甲酸甚至甲烷。产物选择性应通过正确选择反应条件、催化活性金属中心的类型和配体结构来实现。第二个主要目标是获得更多的洞察光催化系统内的能量和电子转移过程（以及分子内）。因此，将进行扩展的光谱研究，以确定化合物从基态开始以及从还原物质开始的物理性质，例如电荷分离态的寿命。中间体的分离和表征应该为理解进行过程的难题增加另一块拼图，这应该导致提出一个精炼的反应机理-特别是对于异双核化合物。