Magnetically separable one dimensional Fe₃O₄/P(MAA-DVB)/TiO₂ nanochains: Preparation, characterization and photocatalytic activity

One dimensional (1D) magnetic Fe₃O₄/P(MAA-DVB)/TiO₂ nanochains as photocatalyst were successfully prepared by a combination of magnetic-field-induced assembly, distillation precipitation polymerization, mixed-solvent hydrolysis and modified hydrothermal method. The as-obtained multilayer core-shell hybrid nanochains were composed of Fe₃O₄ core with excellent magnetic response, polymer in the middle layer aiming to protect Fe₃O₄ from chemical corrosion and an outer TiO₂ shell for the degradation of organic contaminants. SEM, EDS, TEM, FTIR, XPS and TGA analyses indicated that P(MAA-DVB) and TiO₂ were coated on the surface of Fe₃O₄ nanochains layer by layer and the nanochains had a length of several micrometers. The results of XRD proved that the outer TiO₂ shell was anatase which was the most suitable crystal form for photocatalysis. The VSM measurements showed that the saturation magnetization of the magnetic photocatalyst was 35.2 emu/g, making it easy for the photocatalyst to be recovered and recycled by applying an external magnetic field. Moreover, the N₂ adsorption-desorption analysis demonstrated the 1D magnetic Fe₃O₄/P(MAA-DVB)/TiO₂ nanochains were porous with the BET surface area of 32 m²/g. Finally, the photodegradation of rhodamine B (RhB) by the obtained magnetic photocatalyst was investigated via UV-visible absorption spectra. It was found that this kind of 1D photocatalyst had an excellent photodegradation and recycling performance.