Pd nanoparticles supported on pyrazolone-functionalized hollow mesoporous silica as an excellent heterogeneous nanocatalyst for the selective oxidation of benzyl alcohol

Abstract

Hollow mesoporous silica nanoparticles (HMSNs), by exploiting both their organo-functionalized surface and porous shell were chosen as the ideal support for the immobilization of palladium nanoparticles (Pd-NPs). The HMSNs were created by acidic removal of Fe3O4 nanoparticles from silica-coated Fe3O4 core-shell. The catalyst was prepared following surface modification of HMSNs by (3-chloropropyl)-triethoxysilane (CPTES), functionalization by pyrazolone-based ligand, and stabilization of Pd-NPs on HMSNs. The resulting catalyst was fully characterized by different analytical techniques. This new heterogeneous catalyst showed high catalytic activity and excellent selectivity in the selective oxidation of benzyl alcohols in ethanol at ambient temperature. Easy separation by centrifuge and reusability for five successive cycles without significant loss of catalytic activity were some advantages of this catalyst.