Fabrication of Cu (1 0 0) facet-enhanced ionic liquid/copper hybrid catalysis via one-step electro-codeposition for CO2ER toward C2

Abstract

Electrochemical reduction of CO2 (CO2ER) to high value-added multicarbon (C2+) is a viable way to promote carbon–neutral cycle. To date, copper (Cu) is reported as the most effective metal catalyst toward C2+, but it remains a challenge to achieve high selectivity and large current density. Incorporating ionic liquid in Cu-based catalysis has been proved an effective strategy, however, most reported methods are either involved too much ionic liquid (IL) as electrolyte or too complex & unstable. Herein, an ionic liquid-embedded Cu electrocatalyst (Cu-IL/GDL) was innovatively constructed through one-step electro-codeposition method, in which a kind of amino-ionic liquid, AFIL, was anchored to the gas diffusion layer (GDL) and embedded by the deposited Cu. Under the excellent synergy between Cu and AFIL, Cu-IL/GDL exhibits higher faradaic efficiency toward ethylene (C2H4, 40.67%) and C2 (C2H4 and C2H5OH, 61.39%) when directing CO2 to carbon-fiber side of electrode in H-cell. To be precise, more Cu (100) facet is stabilized by the capping effect of AFIL, being in favor for C–C coupling; meanwhile more AFIL+ is embedded by the deposited Cu, making for the initiation of CO2ER. Thus, this paper proposes a facial and effective strategy to reinforce Cu (100) facet, and couple and heighten the virtues of ionic liquid and Cu during CO2ER toward C2.