Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and, Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark.
Angew Chem Int Ed Engl. 2017 Jun 1;56(23):6468-6472. doi: 10.1002/anie.201701104. Epub 2017 May 3.
In a comparative study of the electrocatalytic CO reduction, cobalt meso-tetraphenylporphyrin (CoTPP) is used as a model molecular catalyst under both homogeneous and heterogeneous conditions. In the former case, employing N,N-dimethylformamide as solvent, CoTPP performs poorly as an electrocatalyst giving low product selectivity in a slow reaction at a high overpotential. However, upon straightforward immobilization of CoTPP onto carbon nanotubes, a remarkable enhancement of the electrocatalytic abilities is seen with CO becoming selectively reduced to CO (>90 %) at a low overpotential in aqueous medium. This effect is ascribed to the particular environment created by the aqueous medium at the catalytic site of the immobilized catalyst that facilitates the adsorption and further reaction of CO . This work highlights the significance of assessing an immobilized molecular catalyst from more than homogeneous measurements alone.
在对电催化 CO 还原的比较研究中，钴 meso-四(对苯基)卟啉 (CoTPP) 被用作均相和非均相条件下的模型分子催化剂。在前一种情况下，采用 N,N-二甲基甲酰胺作为溶剂，CoTPP 的电催化性能不佳，在高过电势下反应缓慢，产物选择性低。然而，当 CoTPP 简单地固定在碳纳米管上时，在水溶液中，在低过电势下，CO 被选择性还原为 CO（>90%），电催化能力得到显著增强。这种效应归因于水溶液在固定化催化剂的催化位点处产生的特殊环境，有利于 CO 的吸附和进一步反应。这项工作强调了仅从均相测量评估固定化分子催化剂的重要性。
