Regulating Interfacial Hydrogen-Bonding Networks by Implanting Cu Sites with Perfluorooctane to Accelerate CO₂...

Efficient CO₂ electroreduction (CO₂RR) to ethanol holds promise to generate value-added chemicals and harness renewable energy simultaneously. Yet, it remains an ongoing challenge due to the competition with thermodynamically more preferred ethylene production. Herein, we presented a CO₂ reduction predilection switch from ethylene to ethanol (ethanol-to-ethylene ratio of ~5.4) by inherently implanting Cu sites with perfluorooctane to create interfacial noncovalent interactions. The 1.83 %F-Cu₂O organic-inorganic hybrids (OIHs) exhibited an extraordinary ethanol faradaic efficiency (FE_ethanol) of ∼55.2 %, with an impressive ethanol partial current density of 166 mA cm^-2 and excellent robustness over 60 hours of continuous operation. This exceptional performance ranks our 1.83 %F-Cu₂O OIHs among the best-performing ethanol-oriented CO₂RR electrocatalysts. Our findings identified that C₈F₁₈ could strengthen the interfacial hydrogen bonding connectivity, which consequently promotes the generation of active hydrogen species and preferentially favors the hydrogenation of *CHCOH to *CHCHOH, thus switching the reaction from ethylene-preferred to ethanol-oriented. The presented investigations highlight opportunities for using noncovalent interactions to tune the selectivity of CO₂ electroreduction to ethanol, bringing it closer to practical implementation requirements.