Imidazolium Ions with an Alcohol Substituent for Enhanced Electrocatalytic Reduction of CO2

Abstract Electrochemical reduction of CO 2 to CO is an attractive process for carbon capture and energy regeneration. Imidazolium ionic liquids (IMILs) are promising electrolyte catalytically active additives for this important reaction. Herein, we report functionalizing the imidazolium ion with a propanol substituent at the N site can significantly enhance the catalytic activity of IMILs, causing a positive shift of the onset potential for the CO 2 reduction by about 90 mV in an acetonitrile electrolyte. Theoretical calculations indicated that the propanol hydroxyl could bridge a local hydrogen‐bonding chain as shortcut for proton transfer, leading to a dramatic decrease of the activation barrier for the catalytic reduction of CO 2 in IMIL.