Surface Cuprous Ion Incorporated In Ceria For Highly Selective CO₂ Electroreduction To Ethylene

Metallic copper is the sole known catalyst for electrochemical CO₂ reduction reaction to directly yield a variety of value-added hydrocarbon products.However,Cu-based catalysts have high overpotential,poor catalytic selectivity and stabilization.At present,Cu-based catalysts are mainly oxidation-derived copper,and the Cu⁺ions are the catalytic active sites and easily reduced to Cu⁰ during catalytic reaction,resulting in poor catalytic stabilization.Seeking an effective catalyst alternative to oxidation-derived copper remains an enormous challenge.We report here a novel electocatalyst based on the surfacial cuprous copper（Cu⁺）incorporated into ceria（Cu-CeO₂）.（1）We have incorporated Cu ions into the CeO₂ by Deposition-participation method and controlled the Cu⁺content on the surface of Cu-CeO₂ by different copper ions content and annealing atmosphere.With XRD,Raman and other test method,combined with the structural simulation,the stuctuture of Cu-CeO₂ is the Cu is substitutional incorporation of copper into ceria lattice.（2）We performed electrochemical CO₂ reduction reaction test with Cu-CeO₂ and achieved a highly selective catalysis for ethylene.Cu²⁺and Cu⁰ were excluded by XPS and Auger spectra.The Cu⁺content of Cu-CeO₂ was analyzed.The linear relationship between the selectivity of C₂H₄ and Cu⁺on the surface of Cu-CeO2 was verified.It is further demonstrated that the active site is Cu⁺rather than Cu or OD Cu.With this structure,the Cu⁺can be more stable.（3）The theoretical calculations indicate that Cu⁺facilities binding CO₂ as a reactant and CO as a key intermediate;Cu⁺prefers*CH₂-*CH₂ and*CCO coupling to*CH₂ protonation,resulting in higher selectivity to C₂H₄ than CH₄.Therefore,our Cu-CeO₂ catalyst may become a substitute for oxidation-derived copper catalysts in the CRR field and has a broader application prospect.