Regulating the local microenvironment on porous Cu nanosheets for enhancing electrocatalytic CO2 reduction selectivity to ethylene

Abstract

Local microenvironments of the ECO₂RR play an important role in tuning the adsorption energy of crucial intermediates, which helps enhance ECO₂RR selectivity. Different types of organic polymers were used in this work to modify porous Cu NSs to regulate the local microenvironment and enhance the selectivity of the ECO₂RR to C₂H₄. It is found that when porous Cu NSs are modified with anionic polystyrene vinylbenzyl methylimidazolium chloride (PSMIM), the selectivity of C₂H₄ reaches (62.34 ± 1.48)%, while the selectivity of C₂H₄ on the cationic perfluorosulfonic acid polymer Nafion-modified electrode is only (25.41 ± 1.80)%. CO-DRIFTS, in situ ATR-SEIRAS, and molecular dynamics simulation prove that the presence of PSMIM facilitates the adsorption of CO gas and *CO intermediates on the electrode. High *CO coverage is advantageous for the dimerization of *CO, leading to an enhanced selectivity of C₂H₄. Developing PSMIM-Cu NS electrodes is expected to further accelerate the practical application of porous Cu NSs for the ECO₂RR to produce C₂H₄.