Molecular Electrocatalyst Enables Direct Electrochemical Capture and Conversion of CO ₂ up to Atmospheric Concentration

Abstract

ABSTRACT The conversion of low‐concentration CO 2 streams into fuel is highly desirable for industrial applications, avoiding energy‐intensive CO 2 capture and concentration. Here, we report a highly active molecular electrocatalyst, fac ‐[Mn(CO) 3 (bis‐MeNHC)(MeCN)] + ( 1‐MeCN + ), which enables the direct electrochemical reduction of near‐atmospheric CO 2 concentrations to CO with up to 100% Faradaic efficiency. Voltammetric analysis at varying CO 2 concentrations reveals a clear transition between distinct kinetic regimes, shifting from pure kinetic control to a regime dominated by CO 2 depletion. Kinetic analysis in the 5%–100% CO 2 range reveals a first‐order dependence on substrate concentration. Infrared spectroelectrochemistry confirms that the electrogenerated anionic catalyst remains active under extremely diluted CO 2 conditions. Computational modeling further supports that the CO 2 ‐to‐CO conversion mediated by the doubly reduced species is kinetically accessible at atmospheric CO 2 levels. This work demonstrates molecular electrocatalysis even at CO 2 concentrations as low as 420 ppm (i.e. atmospheric CO 2 partial pressure).