Synergistic Catalysis Induced by Zn-Doping for Steering CO₂ Electroreduction Pathway Toward Ethanol on Cu Catalyst

Electrocatalytic CO₂ reduction reaction (CO₂RR) offers a promising route for sustainable fuel production, yet, improving selectivity toward ethanol remains a great challenge. Here, we report a CuZn bimetallic catalyst with high-index step sites that achieves an ethanol Faradaic efficiency of 46% and stable operation for 100 h at a current density of ∼600 mA cm^{- 2}. Zn-doping does not only modulate the electronic structure of Cu, but also promotes the formation of high-index step sites. Thorough in situ spectroscopic characterizations and density functional theory calculations indicate that this dual effect enables asymmetric ^*CO adsorption in both bridge and atop configurations, thus facilitating C-C coupling and stabilizing the ^*CHCOH intermediate toward ethanol formation. Our findings highlight the synergistic role of electronic tuning and crystal facet engineering in developing efficient CO₂RR catalysts with enhanced ethanol selectivity.