Synthesis of polyaniline-modified Fe3O4/SiO2/TiO2 composite microspheres and their photocatalytic application

Polyaniline-modified Fe3O4/SiO2/TiO2 composite microspheres have been successfully synthesized by sol–gel reactions on Fe3O4 microspheres followed by the chemical oxidative polymerization of aniline. The synthesized multilayer-structured composites were characterized by TEM, XRD, TGA, UV–vis diffuse reflectance spectra and magnetometer. The photocatalytic activity was evaluated by the photodegradation of methylene blue under visible light. The effect of polyaniline (PANI) amounts on the photocatalytic activity was investigated. The photocatalytic activity results show that the Fe3O4/SiO2/TiO2 composites with about 2.4 wt.%–4.1 wt.% PANI could show higher photocatalytic efficiency than that of Fe3O4/SiO2/TiO2. Furthermore, the PANI-Fe3O4/SiO2/TiO2 photocatalyst could be easily recovered using a magnet.

Research highlights
► PANI-modified Fe3O4/SiO2/TiO2 photocatalysts have been synthesized.
► The amount of PANI has influence on the photocatalytic activity.
► The photocatalyst can be easily recovered through magnetic action.