Fabrication and characterization of Fe 3 O 4 @SiO 2 @TiO 2 @Ho nanostructures as a novel and highly efficient photocatalyst for degradation of organic pollution

Abstract In this work we synthesize a novel and highly efficient photocatalyst for degradation of methyl orange and rhodamine B. In addition, a new method for synthesis of Fe 3 O 4 @SiO 2 @TiO 2 @Ho magnetic core-shell nanoparticles with spherical morphology is proposed. The crystal structures, morphology and chemical properties of the as-synthesized nanoparticles were characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDS), X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (DRS) and vibrating sample magnetometer (VSM) techniques. The photocatalytic activity of Fe 3 O 4 @SiO 2 @TiO 2 @Ho was investigated by degradation of methyl orange (MO) as cationic dye and rhodamine B (RhB) as anionic dye in aqueous solution under UV/vis irradiation. The results indicate that about 92.1% of RhB and 78.4% of MO were degraded after 120 and 150 min, respectively. These degradation results show that Fe 3 O 4 @SiO 2 @TiO 2 @Ho nanoparticles are better photocatalyst than Fe 3 O 4 @SiO 2 @TiO 2 for degradation of MO and RhB. As well as, the catalyst shows high recovery and stability even after several separation cycles.

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