Abstract
ABSTRACT
Electrochemical CO
2
reduction to ethylene requires Cu sites that simultaneously enrich carbon intermediates, promote C–C coupling, and suppress hydrogen evolution at high current density. Heteroatom doping is widely used to tune Cu‐based catalysts. However, conventional single‐dopant strategies typically impose either electron donation or electron withdrawal, limiting their ability to balance these coupled interfacial processes. Herein, a Y single‐atom and Cl co‐modified Cu
2
O catalyst (Y
0.19
‐Cu
2
O‐Cl) is developed to create lattice‐confined donor–acceptor pairs for bidirectionally modulating Cu electronic states. Formation energy calculations prove the favorable thermodynamics of Y–Cl co‐doping configuration. HAADF‐STEM, XPS, and XAS support atomically dispersed Y, retained Cl‐containing species, and coupled charge redistribution within the Cu
2
O‐derived matrix. In situ Raman/ATR‐SEIRAS and density functional theory calculations reveal that Y favors *CO enrichment, whereas Cl modifies hydrogen adsorption; the two dopants synergistically regulate Cu
+
active sites and lower the C–C coupling energy barrier from 0.75 to 0.39 eV. Consequently, the catalyst achieves an FE
C2H4
of 62.5% at 656.6 mA cm
−2
and maintains higher ethylene selectivity than the singly modified controls, establishing donor–acceptor electronic pairing as a strategy for industrial‐grade current densities for CO
2
electroreduction.