Ionic liquid-based electrocatalytic CO₂ reduction faces the challenge of achieving high selectivity toward value-added C₂₊ products at high reaction rate (≥ 100 mA cm⁻²). Herein, novel copper@poly(ionic liquid) (Cu@PIL) hybrids demonstrate multi-electron reduction (> 2e^–) with current densities ≥ 300 mA cm⁻². Remarkably, Cu@PIL with F^– anion exhibits high C₂₊ faradaic efficiency of 58 % with a high partial current density of 174 mA cm⁻². Further, a highest C₂₊ partial current density of 233 mA cm⁻² was also achieved. Experimental combined theoretical investigations reveal that the “individual” ionic pairs in the outer PIL layer enrich local CO₂ concentration, thereby promoting the CO₂ supply. Besides, an interfacial electric field is induced by the unbonded imidazolium moieties at Cu-PIL interface, which stabilize intermediates. Anions, differing in the electron-donating number to the imidazolium moieties, influence both the enrichment of CO₂ and the stabilization of intermediates, thus regulating current density and product selectivity.

基于离子液体的电催化CO ₂还原面临着在高反应速率 (≥ 100 mA cm ^-2 )下实现对高附加值 C ₂₊产物的高选择性的挑战。在此，新型铜@聚（离子液体）（Cu@PIL）杂化物表现出电流密度≥ 300 mA cm ^{-2 的}多电子还原（> 2e ^–）。值得注意的是，带有 F ^-阴离子的Cu@PIL表现出58% 的高 C ₂₊法拉第效率和 174 mA cm ^-2的高分电流密度。此外，最高的 C ₂₊部分电流密度为 233 mA cm ^-2也达到了。实验结合理论研究表明，外 PIL 层中的“单个”离子对增加了局部 CO ₂浓度，从而促进了 CO ₂供应。此外，Cu-PIL 界面处未键合的咪唑鎓部分会诱导界面电场，从而稳定中间体。与咪唑鎓部分的给电子数不同的阴离子影响 CO ₂的富集和中间体的稳定，从而调节电流密度和产物选择性。