Molecular‐level insight on CO2 electroreduction to formate facilitated by triazole ionic liquid interfacial microhabitat

Abstract

AbstractThe interfacial microhabitat induced by functionalized ionic liquid (IL) electrolyte can effectively improve product selectivity for CO2 electroreduction. The multiple interactions in IL electrolytes affect the ions, CO2, proton distribution, and the protonation reaction, which are relevant to product selectivity. However, the specific effects are still unclear. Herein, molecular dynamics simulation and density functional theory were combined to reveal the regulatory mechanisms. The results showed that the dipolar interaction between CO2 and [124Triz]− cooperating the hydrogen bonds between [124Triz]− and H2O facilitates the accumulation of H atoms around C atoms of CO2. Moreover, the strong polar [124Triz]− induces protons to attack the C atoms of CO2, which results in lower free energy (−0.10 eV) for the formation of *HCOO intermediate and promotes the formation of formate, compared with the free energy of 0.43 eV for [NTf2]−. This work reveals the [124Triz]− regulatory mechanism for high formate selectivity.