Stable, High-Yield Ethylene Production from Vapor-Assisted Light-Driven Ethane Dehydrogenation

Ethane (C2H6) dehydrogenation (EDH) is a core industrial process for on-purpose ethylene production but is severely constrained by thermodynamics and typically requires elevated temperatures (>600 °C). Light-driven EDH (LDEDH) offers a sustainable alternative by harvesting solar energy to produce ethylene (C2H4) under mild conditions, yet its development has been hindered by low C2H4 productivity and poor operational stability (typically <12 h). Here, we realize a vapor-assisted LDEDH process in a continuous-flow reactor over Pd nanoclusters supported on an interface-engineered ZnO–TiO2 heterojunction in which a conformal TiO2 overlayer on ZnO constructs a lattice-preserving Ti–O–Zn interface that maximizes the interfacial area and enables directional charge separation tailored for oxidative EDH. Mechanistic studies reveal that this strong interfacial synergy drives photogenerated electrons to ZnO and holes to the TiO2 overlayer while Pd nanoclusters promote electron transfer and enhance C2H6 adsorption. As a result, Pd/ZnO-TiO2 achieves a record-high C2H4 productivity of 1640.9 μmol h–1 with a selectivity of 98.7%, surpassing the current state of the art by more than 7-fold and setting a new benchmark for LDEDH. In addition, the presence of water vapor not only supplies ·OH species for LDEDH but also can suppress coke deposition, which enables superior long-term stability for 152 h, largely surpassing that of the reported catalysts (typically below 12 h).