Preparation of a novel Fe3O4@SiO2@Ni–La–B magnetic core–shell nanocomposite for catalytic hydrogenation

Abstract

A novel Fe3O4@SiO2@Ni–La–B magnetic core–shell nanocomposite was prepared by a combination of the Stöber method and self-assembly. In this process, Fe3O4 nanoparticles were first coated with amorphous silica, forming Fe3O4@SiO2 core–shell structural nanocomposites. Ni2+ and La3+ were then loaded onto the surface of Fe3O4@SiO2, followed by reduction with KBH4 to assemble a layer of Ni–La–B onto the surface of Fe3O4@SiO2. The obtained Fe3O4@SiO2@Ni–La–B core–shell nanocomposite has high saturation magnetization (20.6emu/g), compared to that of Ni–La–B (only 0.4emu/g). This magnetic core–shell nanocomposite showed high activity and good selectivity in the catalytic hydrogenation of benzophenone to benzhydrol, and can be easily separated and recycled after reaction.