Electro- und photoreduction of carbon dioxide with heterodinuclear complexes

该项目致力于合成和研究将作为新型催化剂用于二氧化碳还原的物理化学、光和电化学性质的异双核配合物。二氧化碳的多电子还原，优先导致碳氢化合物或醇的产生，仍然是二氧化碳化学活化中的一个根本挑战。将氢化物转移催化剂[MCp*(L)Cl+(M=Ir(III)或Rh(III)；L=双齿配体)与金属羰基配合物Ru(L)(CO)2Cl2或Re(L)(CO)3CL结合在同一分子基质中的新型超分子多功能异双金属配合物是此类催化活性的有效材料。在二氧化碳还原的光催化和电催化过程中，存在两种不同的络合功能，通过p-桥联配体以电子方式偶联，并且两个金属中心在封闭的分子结构中接近，被认为是导致CO(初级两电子还原产物)直接加氢的结果，从而允许产生氢化化合物，如甲醇。本项目的主要目标是合成和详细的物理化学研究(电化学光谱)这类新型的异双金属络合物催化剂的二氧化碳还原。为了进行这项研究，这两个群体的科学互补技能将以协同功能的形式结合在一起，以设计、合成和详细研究新的双功能分子系统。对多电子反应性的机理研究，包括对前体和基本中间体的量子化学计算，将伴随着对新体系的催化性能的实际测试，以改善其性能。

The project is directed at the synthesis and the investigation of physicochemical, photo- and electrochemical properties of heterodinuclear complexes which will to be used as novel catalysts for the electro- and photocatalysis of CO2 reduction. The multielectron reduction of CO2, preferentially leading to the production of hydrocarbons or alcohols, remains a fundamental challenge in the chemical activation of CO2. New kinds of supramolecular multifunctional heterobimetallic complexes which combine in the same molecular matrix a hydride transfer catalyst such as [MCp*(L)Cl+ (M = Ir(III) or Rh(III); L = bidentate ligand) and an electrocatalyst or photocatalyst like the metal carbonyl complexes Ru(L)(CO)2Cl2 or Re(L)(CO)3Cl, capable of reducing CO2 to CO, are proposed as effective materials for this type of catalytic activity. The presence of two different complex functions, coupled electronically by p-bridging ligands, and the proximity of the two metal centres in a closed molecular structure during the photo- and electrocatalysis of CO2 reduction is believed to induce a cooperative effect with the result of direct hydrogenation of CO (the primary two-electron reduction product), allowing for the production of hydrogenated compounds, e.g. methanol. The synthesis and the detailed physicochemical study (electrochemistry spectroscopy) of such new kinds of heterobimetallic complex catalysts of CO2 reduction are the principal objective of this project. To conduct this research, the scientifically complementary skills of both groups will be brought together in a synergistic function to design, synthesize and study in detail the new bifunctional molecular systems. Mechanistic studies of multielectron reactivity, including quantum-chemical calculations of precursors and essential intermediates will accompany the actual tests of the catalytic properties of the new systems in order to improve their performance.