Orientation‐Entropy‐Mediated Derivative Cu Sites for Selective CO ₂ Electroreduction to Ethylene

Electrocatalytic conversion of CO 2 to ethylene (C 2 H 4 ) provides a sustainable route for decarbonized chemical manufacturing. Cu‐based catalysts are uniquely capable of driving the C−C coupling essential for C 2 H 4 formation, yet their practical implementation is limited by uncontrollable dynamic reconstruction that deteriorates both selectivity and stability. Here, we develop an orientation‐entropy‐mediated regulation strategy to programmatically direct the structural evolution of Cu 2 O toward highly active sites for C 2 H 4 electrosynthesis. Remarkably, the medium‐entropy Cu 2 O catalyst achieves a high C 2 H 4 Faradaic efficiency of ∼75% at an industrial‐level current density of 400 mA cm −2 and operates stably for over 80 h. Operando spectroscopy combined with experimental analysis reveals that entropy‐regulated Cu sites establish an optimized kinetic balance between C−C coupling and competing *CO hydrogenation, thereby promoting the energetically preferred formation of the key *CO−*COH intermediate. Preliminary techno‐economic analysis projects an additional profit of $566 per ton of C 2 H 4 , and life‐cycle assessment demonstrates an overall ∼42% reduction in environmental impact compared to conventional production routes.