Catalysis Science Group, Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA, 99352, USA.
Chemistry. 2018 Nov 16;24(64):16964-16971. doi: 10.1002/chem.201801759. Epub 2018 Jul 27.
Molecular catalysts for hydrogenation of CO are widely studied as a means of chemical hydrogen storage. Catalysts are traditionally designed from the perspective of controlling the ligands bound to the metal. In recent years, studies have shown that the solvent can also play a key role in the mechanism of CO hydrogenation. A prominent example is the impact of the solvent on the thermodynamic hydride donor ability, or hydricity, of metal hydride complexes relative to the hydride acceptor ability of CO . In some cases, simply changing from an organic solvent to water can reverse the direction of hydride transfer between a metal hydride and CO . Additionally, the solvent can impact catalysis by converting CO into carbonate species, as well as activate intermediate products for hydrogenation to more reduced products. By understanding the substrate and product speciation, as well as the reactivity of the catalyst towards the substrate, the solvent can be used as a central design component for the rational development of new catalytic systems.
作为化学储氢的一种手段，用于 CO 氢化的分子催化剂得到了广泛研究。传统上，催化剂是从控制与金属结合的配体的角度来设计的。近年来，研究表明溶剂在 CO 氢化的机理中也可以起到关键作用。一个突出的例子是溶剂对金属氢化物配合物相对于 CO 的氢化物接受能力的热力学供氢体能力（hydricity）的影响。在某些情况下，只需将有机溶剂简单地替换为水，就可以改变金属氢化物和 CO 之间氢化物转移的方向。此外，溶剂可以通过将 CO 转化为碳酸盐物种来影响催化作用，并激活加氢的中间产物以生成更还原的产物。通过了解底物和产物的形态以及催化剂对底物的反应性，可以将溶剂用作合理开发新催化体系的核心设计组件。
