Fe3O4@SiO2-L-Cu(II): An efficient and easily recoverable catalyst for reducing/degrading environmental pollutants in aqueous medium

Abstract In the present study, a magnetically recoverable catalyst is synthesized through immobilizing copper (II) over the Fe3O4@SiO2 nanoparticles (NPs) surface [Fe3O4@SiO2-L-Cu (II)] (L = pyridine-4-carbaldehyde thiosemicarbazide). Accordingly, synthesized catalysts were determined and characterized by energy dispersive X-ray spectrometry (EDS), Fourier transforms infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), vibrating sample magnetometer (VSM), and thermogravimetric-differential thermal analysis (TG-DTA) procedures. Using [Fe3O4@SiO2-L-Cu (II)], 4-Nitrophenol (4-NP), Cr(VI), and organic dyes, e.g., Methylene blue (MB) and Congo Red (CR) were reduced in aqueous media. As shown by results of Catalytic performance investigations, [Fe3O4@SiO2-L-Cu (II)] performance was outstanding concerning reduction reactions in mild conditions. Remarkable attributes of this method are high efficiency, removal of a homogeneous catalyst, easy recovery from the reaction mix, and uncomplicated route. The amount of activity in this catalytic system was almost constant after several stages of recovery and reuse. The results show that the catalyst was efficient and easily recoverable in the successive run without a significant loss of catalytic efficiency.