Electrified Acetylene Removal From Ethylene Streams Enabled by Facet‐Engineered Cu–TiO ₂ Interfaces

ABSTRACT

Removal of trace acetylene from ethylene is essential for polymer‐grade olefin production, yet current thermocatalytic purification requires elevated temperatures and hydrogen input. Here we report an electrified route for acetylene removal from ethylene streams using facet‐engineered Cu–TiO ₂ interfaces. By tuning the exposed facets of anatase TiO ₂ , we regulate the interfacial electronic interaction with supported Cu nanoclusters and thereby the balance among acetylene hydrogenation, hydrogen evolution, and carbon–carbon coupling. Among the catalysts examined, Cu–TiO ₂ {001} provides the most effective interfacial environment for selective acetylene‐to‐ethylene conversion, delivering an ethylene Faradaic efficiency (FE) of 95.4% under acetylene‐rich feed. Under purification‐relevant acetylene‐lean conditions, a 25 cm ² flow electrode suppresses residual acetylene to below 5 ppm while maintaining H ₂ FE below 5% during prolonged operation. Combined spectroscopy and theory indicate that the {001} facet strengthens Cu–TiO ₂ electronic coupling, stabilizes the Cu electronic structure and key hydrogenation intermediates under operating conditions, and disfavors competing pathways. Techno‐economic analysis supports the process potential of this electrified purification strategy.