Zeolite confinement and defect engineering steering the photocatalytic conversion of CO2 to C2H4

Abstract

The photocatalytic reduction of carbon dioxide (CO₂) into high-value-added chemicals represents a promising strategy to address the energy crisis and global warming. Among various reduction products, the selective generation of ethylene (C₂H₄) remains particularly challenging. In this study, Ag and Cu_xO nanoparticle co-modified zeolite TS-1 (Ag–Cu_xO/TS-1) was successfully synthesized via a combined ion exchange and in situ reduction approach. Under simulated solar light irradiation, the optimized Ag–Cu_xO/TS-1 catalyst achieves efficient CO₂-to-C₂H₄ conversion, yielding a remarkable C₂H₄ production rate of 2.02 μmol g⁻¹ h⁻¹ with 100% selectivity toward C₂H₄. The remarkable activity and selectivity originate from the uniform dispersion of active sites, and the intimate interfacial contact of Cu_xO and Ag and its optimized CO₂ adsorption and broad-spectrum light harvesting capability collectively promote the separation of photogenerated charges and facilitate enrichment of *CO and C–C coupling, as proven by in situ Raman spectroscopy. Moreover, the catalyst demonstrates excellent recyclability, maintaining over 80% of its initial activity after four consecutive reaction cycles. This work highlights the potential of coupling plasmonic metals with zeolite-based confinement environments and defect engineering, providing a feasible strategy for the efficient and selective conversion of CO₂ into value-added C₂ products.