Immobilization of a Molecular Re Complex on MOF‐derived Hierarchical Porous Carbon for CO<sub>2</sub> Electroreduction in Water/Ionic Liquid Electrolyte
Domenico Grammatico, Huan Ngoc Tran, Yun Li, Silvia Pugliese, Laurent Billon, Bao‐Lian Su, Marc Fontecave
Abstract
The development of molecular catalysts for CO2 electroreduction within electrolyzers requests their immobilization on the electrodes. While a variety of methods have been explored for the heterogenization of homogeneous complexes, a novel approach using a hierarchical porous carbon material, derived from a metal–organic framework, is reported as a support for the well-known molecular catalyst [Re(bpy)(CO)3Cl] (bpy=2,2’-bipyridine). This cathodic hybrid material, named Re@HPC (HPC=hierarchical porous carbon), has been tested for CO2 electroreduction using a mixture of an ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate, EMIM) and water as the electrolyte. Interestingly, it catalyzes the conversion of CO2 into a mixture of carbon monoxide and formic acid, with a selectivity that depends on the applied potential. The present study thus reveals that Re@HPC is a remarkable catalyst, enjoying excellent activity (turnover numbers for CO2 reduction of 7835 after 2 h at −1.95 V vs. Fc/Fc+ with a current density of 6 mA cm−2) and good stability. These results emphasize the advantages of integrating molecular catalysts onto such porous carbon materials for developing novel, stable and efficient, catalysts for CO2 reduction. The authors declare no conflict of interest. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.