One-step synthesis of Pd nanoparticles functionalized crystalline nanoporous CeO2 and their application for solvent-free and aerobic oxidation of alcohols

Abstract

Crystalline nanoporous CeO2 (CM-CeO2) has been successfully prepared through self assembly of poly 4-vinylpyridine (P4VP) template with Ce(NO3)3·6H2O precursor based on their strong acid–base interactions under high temperature (180°C) hydrothermal conditions. After calcination of the sample at 550°C in the air, crystalline nanoporous CeO2 with opened nanopores was obtained. Pd nanoparticles acted as active species could be easily introduced into the sample, which gives the sample of CM-CeO2-Pd-1.0 (where 1.0 stands for weight percentage of Pd). CM-CeO2-Pd-1.0 exhibits very good catalytic activity (Conv. 82.1%) and selectivity (97.6%) for aerobic oxidation of benzyl alcohol under solvent-free conditions. The enhanced catalytic performance of CM-CeO2-Pd-1.0 should be attributed to synergistic effects between abundant nanopores, unique oxygen storage and release properties of CM-CeO2 support. The preparation of CM-CeO2-Pd-1.0 may help develop cost-effective and efficient catalysts for aerobic oxidation of various alcohols into useful fine chemicals under mild conditions.