CO 2 electroreduction is among the most promising approaches used to transform this green-house gas into useful fuels and chemicals. Ionic liquids (ILs) have already proved to be the adequate media for CO 2 dissolution, activation, and stabilization of radical and ionic electrochemical active species in aqueous solutions. In general, IL electrolytes reduce the overpotential, increase the current density, and allow for the modulation of solution pH, driving product selectivity. However, little is known about the main role of these salts in the CO 2 reduction process the assumption that ILs form solvent-separated ions. However, most of the ILs in solution are better described as anisotropic fluids and display properties of an extended cooperative network of supramolecular species. That strongly reflects their mesoscopic and nanoscopic organization, inducing different processes in CO 2 reduction compared to those observed in classical electrolyte solutions. The major aspects concerning the relationship between the structural organization of ILs and the electrochemical reduction of CO 2 will be critically discussed considering selected recent examples.

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Electrocatalysis of CO2 reduction in aqueous electrolytes containing the ionic liquid (IL) 1‐n‐butyl‐2,3‐dimethylimidazolium acetate ([BMMIm][OAc]) and DMSO proceeded at low overpotentials (−0.9 V vs. Ag/AgCl) at commercially‐available Au electrodes, with high selectivity for CO production (58 % faradaic efficiency at −1.6 V vs. Ag/AgCl). 0.43 mol CO2 per mol IL could be absorbed into the electrolyte at atmospheric pressure, forming bicarbonate and providing a constant supply of dissolved CO2 to the surface of the electrode. Electrocatalysis of CO2 reduction in the electrolyte was facilitated by stabilization of CO2 radical anions by the imidazolium cations of the IL and buffer‐like effects with bicarbonate.

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