Dr Zakaria Halime, Chargé de Recherche CNRS à l’Université de Paris-Saclay, Institut de Chimie Moléculaire et des Matériaux d’Orsay, donnera une conférence intitulée « From Electro- to Photo-catalysis, the Journey of a Bio-inspired Catalyst for CO2 Reduction »
Résumé : In order to store and use energy in the form of oxidant or reductant equivalents, Nature’s most successful strategies lie in the synchronization of several redox reactions orchestrated by a series of metal-enzymes. As a result of natural genetic mutations over the last four billion years, active sites of these metal enzymes evolved to perform catalytic reactions with a minimum energy consumption and high efficiency and selectivity. In these active sites, built around a metal center with an optimized geometry and redox properties, the second coordination sphere, constituted by amino acid residues, plays a major role in the reactivity of the enzyme. Inspired by the active site of Carbon Monoxide Dehydrogenase (CODH), known to catalyze the reversible reduction of CO2 to CO, we developed a series of modified iron-porphyrin catalysts where multipoint hydrogen-bonding were introduced in the second coordination sphere of the metal center. Using these modified iron-porphyrin catalysts, we were able to show that meticulous 3D positioning of these functional groups can help improve and modulate the electro- and photocatalytic performances.
