A nanohybrid self-assembled from exfoliated layered vanadium oxide nanosheets and Keggin Al13 for selective catalytic oxidation of alcohols

Abstract

A nanoscale hybrid material (V₂O₅–Al₁₃) for highly efficient alcohol oxidation is synthesized through electrostatic self-assembly between oppositely charged Keggin Al₁₃ polyoxocations and exfoliated V₂O₅ nanosheets. The analyses by X-ray diffraction, electron microscopy, X-ray photoelectron spectroscopy and structural consideration based on charge balance indicate that the Keggin Al₁₃ ions could be sparsely distributed in the nanosheet galleries. The as-prepared catalyst successfully achieved high catalytic activity toward alcohols (96.8% sel.) with the oxygen molecule as an ideal oxidant under mild conditions. Also, the nanohybrid showed an outstanding adsorption capability for benzyl alcohol (773 mg g⁻¹). In comparison to individual exfoliated V₂O₅ nanosheets and bulk V₂O₅, the V₂O₅–Al₁₃ nanohybrid catalyst exhibited superior catalytic activity and selectivity under the same experimental conditions. The results highlight the outstanding functionality of the V₂O₅–Al₁₃ nanohybrid as an efficient oxidation catalyst. A detailed study of its structure–activity relationship showed that the high performance of the V₂O₅–Al₁₃ nanohybrid is attributed to the adsorption–catalysis synergistic effect between V₂O₅ and Al₁₃.