Molecular Electrochemical Reduction of COx-to-Methanol with Cobalt Phthalocyanines Combined Electrochemical and Spectroscopic Studies

Reduction of carbon dioxide has as main objective the production of useful organic compounds and fuels - renewable fuels - in which solar energy would be stored. Molecular catalysts can be employed to reach this goal, either in photochemical or electrochemical (or combined) contexts. They may in particular provide excellent selectivity thanks to easy tuning of the electronic properties at the metal and of the ligand second and third coordination sphere. Hybridization of the catalysts with conductive or semi-conductive materials may lead to enhance stability and new catalytic properties, as well as the development of devices (electrolyzers). Recently, we have found that Co phthalocyanine adsorbed at carbon nanotubes can convert CO2 to CO, and CO to methanol, opening the path to a cascade process for the production of CH3OH. Upon combining electrochemical and spectroscopic studies (IR, XAS), we have uncovered the reasons for such remarkable reactivity. Our most recent results will be discussed, including the insertion of this catalyst into a flow cell. References 1. E. Boutin, M. Robert et al., Angew. Chem. Int. Ed. 2019, 58, 16172-16176 2. E. Boutin, M. Robert et al. Chem. Eur. J. 2022, e202200697 3. B. Liu, M. Robert et al., submitted