Synthesis of core–shell nanostructured magnetic photocatalyst Fe3O4@SiO2@Ag3PO4 with excellent visible-light-responding photocatalytic activity

A core–shell nanostructured magnetic photocatalyst Fe 3 O 4 @SiO 2 @Ag 3 PO 4 with a grain size ranging from 200 to 400 nm was prepared via a facile and effective method. The as-prepared products were characterized using X-ray diffraction, high-angle annular dark field-scanning transmission electron microscopy, energy-dispersive spectroscopy, and UV–Vis diffuse reflectance spectra. The photocatalytic activity was evaluated by the degradation of 10 −5  M RhB solution under visible light irradiation with a cut-off filter ( λ  ≥ 420 nm). The results showed that nearly 100 % color removal efficiency was achieved in 45 min with the presence of Fe 3 O 4 @SiO 2 @Ag 3 PO 4 photocatalyst. Furthermore, it can be easily recollected from the solution by magnetic separation and efficiently recycled without major loss of activity due to its superior magnetic responsibility and extremely high reusability, exhibiting highly potential applications in water purification avoiding the secondary pollution.