Preparation and characterization of Fe3O4/SiO2/CdS nanocomposites as efficient magnetic photocatalysts for the reduction of nitro compounds under visible LED irradiation

A series of magnetic Fe3O4/SiO2/CdS nanocomposites were synthesized through a facile and convenient method. The characterization of the prepared nanocomposites was performed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), vibrating sample magnetometer (VSM), UV-Vis spectroscopy, and UV-vis diffuse reflectance spectroscopy (DRS). The prepared magnetic photocatalysts were first utilized for the photocatalytic reduction of nitro compounds under visible LED irradiation. The Fe3O4/SiO2/CdS nanocomposites exhibited enhanced photoactivity compared with the bare CdS and commercial CdS (Aldrich). The results demonstrated that Fe3O4/SiO2/CdS nanocomposites have potential to provide a promising visible light driven photocatalyst for the selective reduction of nitro compounds to corresponding amines under mild conditions. The prepared photocatalyst can be recovered by magnetic separation and successfully reused for 3 cycles.