Structuring Cu Membrane Electrode for Maximizing Ethylene Yield from CO₂ Electroreduction

Electrocatalytic ethylene (C₂H₄) evolution from CO₂ reduction is an intriguing route to mitigate both the energy and environmental crises; however, to acquire industrially relevant high productivity and selectivity at low energy cost remains to be challenging. Membrane assembly electrode has shown great prospect and tailoring its architecture for maximizing C₂H₄ yield at minimum voltage with long-term stability becomes critical. Here a freestanding Cu membrane cathode is designed and constructed by electrochemically depositing mesoporous Cu film on Cu foam to simultaneously manage CO₂, electron, water, and product transport, which shows an extraordinary C₂H₄ Faradaic efficiency of 85.6% with a full cell power conversion efficiency of 33% at a current density of 368 mA cm^-2, heading the techno-economic viability for electrocatalytic C₂H₄ production.