Ionic liquid-mediated synthesis of crystalline CeO2 mesoporous films and their application in aerobic oxidation of benzyl alcohol

In this work, mesoporous CeO2 crystalline film was prepared via calcining the solution of Ce(NO3)3 in ionic liquid (1-allyl-3-methylimidazolium chloride) containing cellulose. The as-prepared CeO2 film was characterized by means of different techniques including X-ray diffraction, transmission electron microscopy equipped with energy dispersive X-ray spectroscopy, scanning electron microscopy and nitrogen sorption analysis. It was indicated that the as-prepared CeO2 film was composed of numerous CeO2 crystals with size of ∼9 nm, which assembled with each other to form interconnected channels within the film. The BET specific surface area and the pore volume of the CeO2 film were estimated to be 62 m2/g and 0.15 cm3/g, respectively, based on the N2 sorption isotherms. Being used as a support, the CeO2 film was loaded with Au nanoparticles of ∼5 nm in size via the reduction of HAuCl4 with NaBH4 in aqueous solution. The as-synthesized Au/CeO2 nanocomposite demonstrated a good catalytic activity for aerobic oxidation of benzyl alcohol.