Department of Chemical Sciences, University of Padova, Via Marzolo, 1, 35131, Padova, Italy.
Laboratoire d'Electrochimie Moléculaire, Université de Paris, Laboratoire d'Electrochimie Moléculaire, CNRS, 75006, Paris, France.
ChemSusChem. 2020 Aug 21;13(16):4111-4120. doi: 10.1002/cssc.202001143. Epub 2020 Aug 3.
Iron complexes with a N O -type N,N'-bis(salicylaldehyde)-1,2-phenylenediamine salophen ligand catalyze the electrochemical reduction of CO to CO in acetonitrile with phenol as the proton donor, giving rise to 90-99 % selectivity, faradaic efficiency up to 58 %, and turnover frequency up to 10 s at an overpotential of 0.65 V. This novel class of molecular catalyst for CO reduction operate through a mononuclear Fe intermediate, with phenol being involved in the process with first-order kinetics. The molecular nature of the catalyst and the low cost, easy synthesis and functionalization of the salophen ligand paves the way for catalyst engineering and optimization. Competitive electrodeposition of the coordination complex at the electrode surface results in the formation of iron-based nanoparticles, which are active towards heterogeneous electrocatalytic processes mainly leading to proton reduction to hydrogen (faradaic efficiency up to 80 %) but also to the direct reduction of CO to methane with a faradaic efficiency of 1-2 %.
铁配合物与 N,O-型 N,N'-双（水杨醛）-1,2-苯二胺席夫碱配体催化 CO 在乙腈中的电化学还原，以苯酚作为质子供体，选择性高达 90-99%，法拉第效率高达 58%，在 0.65 V 的过电势下，周转率频率高达 10 s。这种新型的 CO 还原分子催化剂通过单核 Fe 中间体起作用，苯酚以一级动力学参与该过程。催化剂的分子性质以及席夫碱配体的低成本、易合成和功能化，为催化剂工程和优化铺平了道路。在电极表面上配位复合物的竞争电沉积导致形成铁基纳米粒子，这些纳米粒子对异相电催化过程具有活性，主要导致质子还原为氢（法拉第效率高达 80%），但也可以将 CO 直接还原为甲烷，法拉第效率为 1-2%。
