Novel Leaking-Free, Green, Double Core/Shell, Palladium-Loaded Magnetic Heterogeneous Nanocatalyst for Selective Aerobic Oxidation

Abstract

A new nanocatalyst containing Fe3O4 as a core, coated by a thin layer of SiO2, a mesoporous TiO2 shell, functionalized with diethylenetriamine (DETA) substituents and palladium nanoparticles dispersed on the surface and coordinated to organic groups was prepared. It exhibited spherical morphology with an average size of 178 nm and possess 195 m2 g−1 surface area and 2.4 nm pore diameter with a saturation magnetization of 20.7 emu g−1. Inductively coupled plasma spectroscopy proved Pd loading via porosity and functionality by DETA groups up to 10 wt% and the leaking-free property of the nanocatalyst. Furthermore, the nanocatalyst exhibited high efficiency for the selective aerobic oxidation of alcohols to aldehydes or ketones. Graphical Abstract