Oxygen Vacancy-Dependent Photocatalytic Selective Synthesis of an Unsaturated Amide on Spinel CuFe₂O₄

Abstract

Oxygen vacancies can change the physical and chemical properties of oxide semiconductors, which is applied to the field of ph otocatalysis, including water splitting, carbon dioxide reduction, and organic synthesis. However, the mechanism of oxygen vacancies in photocatalytic organic synthesis is still unclear. Herein, oxygen vacancies constructed on spinel CuFe 2 O 4 nanoparticles were found to trigger the photocatalytic synthesis of an unsaturated amide with high conversion and selectivity. Such superior performance was attributed to the fact that the enriched surface oxygen vacancies could increase the charge separation efficiency and optimize the reaction path, which has been demonstrated both experimentally and theoretically.

Light-assisted thermochemical reduction of CuFe2O4 within a photo-thermogravimetric analyser for solar fuel production

“…Contributions at 530.2 and 531.2 eV could be distinguished after Gaussian fitting, which are attributed to the lattice oxygen (O L ) and (O V ), respectively. Observation of a higher proportion of O V area indicates an increased concentration of O V after PTR [48].…”

“…The smaller the diameter of the circle, the higher the charge transfer rate that can be reached [47]. The reduced sample exhibited a smaller semicircle diameter than the fresh sample and cycled sample, corresponding to the enhanced charge transfer of photo-induced carriers due to the effects of V O s [48]. It could be found that the reduced sample (under illumination) showed the lowest interfacial electron transfer resistance; this confirmed that most V O s were produced in the reduced sample (under illumination).…”

Beneficial Synergistic Intermetallic Effect in ZnCo2O4 for Enhancing the Limonene Oxidation Catalysis

“…Transitional metal oxides are promising candidate catalysts in various catalytic reactions due to their storage abundance, component variety, variable oxidation states, high stability, and adjustable geometric/electronic structure. − As one of the most studied transitional metal oxides, spinel Co 3 O 4 stands out owing to its good redox capability, facile oxygen mobility, and relatively weak Co–O bond strength. − Partially substituting Co in the Co 3 O 4 lattice with a second metal is a common strategy to achieve the performance enhancement via synergistic catalysis when single Co 3 O 4 cannot meet all the requirements. Especially, well-defined bimetallic ACo 2 O 4 spinels (A = Ni, Cu, Mg, etc.…”