Laboratoire de Chimie Moléculaire, CNRS et Ecole Polytechnique
Vendredi 5 octobre à 14h (salle Magat) :
“Proton-Coupled Electron Transfer : from Molecular Models to Catalytic Systems”
Résumé
Proton-Coupled Electron Transfer (PCET) reactions are found to be ubiquitous in nature, and are involved in numerous natural and artificial processes. The understanding of such transfer mechanism is crucial to get a more comprehensive glimpse of complex biological processes, as well as a better view of the potential implication of PCET reactions in the catalytic activation of small molecules (e.g. H2O, O2 or CO2). This would conceivably end up in the depiction of crucial parameters to obtain economically viable molecules / materials towards the development of cheap, sustainable and robust catalysts.
Through different examples involving molecular [1] and nanomaterials [2], we will illustrate how electrochemistry, and notably cyclic voltammetry, can help the understanding of different types of PCET reactions.
[1] Costentin, C. ; Robert, M. ; Savéant, J.-M. ; Tard, C., Inserting a hydrogen-bond relay between proton exchanging sites in proton-coupled electron transfers. Angew. Chem. Int. Ed. 2010, 49 (22), 3803 ;
Costentin, C. ; Hajj, V. ; Robert, M. ; Savéant, J.-M. ; Tard, C., Concerted heavy-atom bond cleavage and proton and electron transfers illustrated by proton-assisted reductive cleavage of an O–O bond. Proc. Natl. Acad. Sci. U. S. A. 2011, 108 (21), 8559 ;
Savéant, J.-M. ; Tard, C., Proton-coupled electron transfer in azobenzene-hydrazobenzene couples with pending acid-base functions. Hydrogen-bonding and structural effects. J. Am. Chem. Soc. 2014, 136 (25), 8907.
[2] Costentin, C. ; Di Giovanni, C. ; Giraud, M. ; Savéant, J.-M. ; Tard, C., Nanodiffusion in electrocatalytic films. Nat. Mat. 2017, 16 (10), 1016.
