(i) Molecular Catalysis of Electrochemical Reactions.
(ii) Principles and Applications to Small Molecules Activation.

Abstract

Solar-driven electrochemical splitting of water to molecular hydrogen and oxygen, along with the reduction of carbon dioxide are small molecule transformations that hold promise as routes of storing sunlight in energy-dense chemical bonds. Activation penalties require the help of catalysts, usually transition metal derivatives. We will provide the basic principles of molecular catalysis of electrochemical reactions based on the use of cyclic voltammetry as an analytical tool. 1 Then several examples will be discussed: (i) catalysis of the CO2-to-CO conversion with iron porphyrins to illustrate how mechanism analysis can lead to an intelligent design of a catalyst; 2 (ii) catalysis of hydrogen production conversion with iron porphyrins emphasizing the role of a cocatalyst; 3 (iii) catalysis of the O2-to-H2O conversion with manganese porphyrins showing the crucial role of proton couple electron transfer (PCET) in the process; 4 finally (iv) catalysis of N2O electroreduction to N2 to illustrate the differences between redox catalysis and chemical catalysis. 5


References

1. Savéant, J-M.; Costentin, C. Elements of Molecular and Biomolecular Electrochemistry, 2nd Ed., Wiley, 2019, Chap. 5.
2. Costentin, C.; Savéant, J-M. Nat. Rev. Chem. 2017, 1, 0087.
3. Margarit, C. G.; Asimow, N. G.; Thorarinsdottir, A.; Costentin, C.; Nocera, D. G. ACS Catal. 2021, 11, 4561-4567.
4. Passard, G; Dogutan, D. K.; Qiu, M.; Costentin, C.; Nocera, D. G. ACS Catalysis 2018, 8, 8671-8679.
5. (a) Deeba, R.; Molton, F.; Chardon-Noblat, S.; Costentin C. ACS Catal. 2021, 11, 6099-6103. (b). Deeba, R.; Chardon-Noblat, S.; Costentin, C. Chem. Sci. 2021, 12, 12726-12732.


Biography

Professor Cyrille Costentin received his undergraduate education at Ecole Normale Supérieure in Cachan and pursued his graduate studies at the University Paris Diderot (Paris 7), where he received his Ph.D. in 2000. He joined the faculty at the University of Paris Diderot as associate professor in 2001. He was promoted professor in 2007. His area of expertise includes mechanisms and reactivity in electron transfer chemistry with particular recent emphasis on electrochemical and theoretical approaches to proton-coupled electron transfer processes and catalytic processes for small molecule activation. He is an expert in molecular electrochemistry and was a Visiting Scholar at Harvard University from 2016 to 2019 working with Prof. D. G. Nocera. In September 2019 he joined the Département de Chimie Moléculaire at the Université Grenoble-Alpes.