Ag-deposited silica-coated Fe_3O_4 magnetic nanoparticles catalyzed reduction of p-nitrophenol

摘要

In this paper, a novel approach was successfully developed for advanced catalyst Ag-deposited silica-coated Fe_3O_4 magnetic nanoparticles, which possess a silica coated magnetic core and growth active silver nanoparticles on the outer shell using n-butylamine as the reductant of AgNO_3 in ethanol. The as-synthesized nanoparticles have been characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), Fourier transform infrared spectra (FT-IR), vibration sample magnetometer (VSM), and have been exploited as a solid phase catalyst for the reduction of p-nitrophenol in the presence of NaBH_4 by UV-vis spectrophotometry. The obtained products exhibited monodisperse and bifunctional with high magnetization and excellent catalytic activity towards p-nitrophenol reduction. As a result, the as-obtained nanoparticles showed high performance in catalytic reduction of p-nitrophenol to p-aminophenol with conversion of 95% within 14min in the presence of an excess amount of NaBH_4, convenient magnetic separability, as well as remained activity after recycled more than 6 times. The Fe_3O_4@SiO_2-Ag functional nanostructure could hold great promise for various catalytic reactions.