Smart Electrode Surfaces by Electrolyte Immobilization for Electrocatalytic CO Conversion.

The activity and selectivity of molecular catalysts for the electrochemical CO reduction reaction (CORR) are influenced by the induced electric field at the electrode/electrolyte interface. We present here a novel electrolyte immobilization method to control the electric field at this interface by positively charging the electrode surface with an imidazolium cation organic layer, which significantly favors CO conversion to formate, suppresses hydrogen evolution reaction, and diminishes the operating cell voltage. Those results are well supported by our previous DFT calculations studying the mechanistic role of imidazolium cations in solution for CO reduction to formate catalyzed by a model molecular catalyst.