Nanohybrid Self-Assembled by Exfoliated Layered Vanadium Oxide Nanosheets with 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 analysis by X-ray diffraction, electron microscopy, X-ray photoelectron spectrum and structural consideration based on charge balance indicate that 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 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 experiment condition. The result highlights 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 V2O5-Al13 nanohybrid is attributed to the adsorption-catalytic synergistic effect between V2O5 and Al13.