Electroreduction of CO 2 to Formate with Low Overpotential using Cobalt Pyridine Thiolate Complexes

作者：Subal Dey, Tanya K. Todorova, Marc Fontecave, Victor Mougel · 发表于：Angewandte Chemie International Edition · 年份：2020 · DOI：10.1002/anie.202006269 · 被引用次数：73 · 研究领域：CO2 Reduction Techniques and Catalysts、Ionic liquids properties and applications、Advanced battery technologies research

Abstract Electrocatalytic CO 2 reduction to value‐added products provides a viable alternative to the use of carbon sources derived from fossil fuels. Carrying out these transformations at reasonable energetic costs, for example, with low overpotential, remains a challenge. Molecular catalysts allow fine control of activity and selectivity via tuning of their coordination sphere and ligand set. Herein we investigate a series of cobalt(III) pyridine‐thiolate complexes as electrocatalysts for CO 2 reduction. The effect of the ligands and proton sources on activity was examined. We identified bipyridine bis(2‐pyridinethiolato) cobalt(III) hexaflurophosphate as a highly selective catalyst for formate production operating at a low overpotential of 110 mV with a turnover frequency (TOF) of 10 s −1 . Electrokinetic analysis coupled with density functional theory (DFT) computations established the mechanistic pathway, highlighting the role of metal hydride intermediates. The catalysts deactivate via the formation of stable cobalt carbonyl complexes, but the active species could be regenerated upon oxidation and release of coordinated CO ligands.