Electrografting of organic layer on Cu-based electrode surface for improving C-C coupling during CO 2 electroreduction Duy Thai Nguyen 1 , Ngoc Huan Tran 1 , Amal Lakhal 2 , Cyril Ollivier 2 , Louis Fensterbank 1 , Marc Fontecave 1 1 College de France, France, 2 Sorbonne University, France The aqueous electrocatalytic CO 2 reduction reaction (CO 2 RR) has attracted significant attention for its potential to convert the greenhouse gas CO 2 into valuable chemicals. Copper is the most promising electrocatalysts of converting CO 2 into multicarbon (C 2+ ) products via C-C coupling reaction. However, the broad range of products (including C 1 products, such as formic acid, CO) leads to challenges in improving the selectivity of C 2+ products. In this study, various radical precusors such as aryl diazonium, iodonium, sulfonium, and silicate compounds are electrochemically grafted onto copper-based electrode surfaces to form an organic layer. This layer enhances the selectivity towards C 2+ products compared to pristine copper electrode by promoting C–C coupling reactions. Furthermore, despite the grafted layer being generated the same aryl radicals, the selectivity was varied depending on the radical precursor. This variation is attributed to residues introduced during the grafting process, which influence the reaction pathways in CO 2 RR. XPS and EDS analyses confirm the presence of these impurities, highlighting their impact on catalytic performance. References 1. D. Wakerley, S. Lamaison, F. Ozanam, N. Menguy, D. Mercier, P. Marcus, M. Fontecave, V. Mougel. Nature Materials 2019, 18, 1222; 2. C. E. Creissen, J. G. Rivera de la Cruz, D. Karapinar, D. Taverna, M.W. Schreiber, M. Fontecave. Angew.Chem. Int. Ed. 2022, 61, e202206279. 3. N. B. Watkins, Y. Wu, W. Nie, J. C. Peters, T. Agapie, ACS Energy Lett. 2023, 8, 189-195. 4. V. Corcé, L.-M. Chamoreau, E. Derat, J.-P. Goddard, C. Ollivier, L. Fensterbank, Angew. Chem. Int. Ed. 2015, 54, 11414- 11418.
P69
© The Author(s), 2025
Made with FlippingBook Learn more on our blog