Rapid synthesis of recyclable and reusable magnetic TiO2@Fe3O4 for degradation of organic pollutant

The effect of calcination temperature and catalyst dosage on degradation rate of methyl orange has been investigated and 0.04 g TiO2 with 700 °C calcination temperature was selected as the object of doping due to its higher degradation efficiency (99% in less than 1 h), Fe3O4 modified with citric acid was used to improve the recovery and reuse of catalyst, the effect of doping amount of Fe3O4 on the photo-catalytic efficiency of methyl orange has been discussed, and the results showed that the methyl orange degraded above 97% with 20 mg Fe3O4 doped into TiO2 when the TiO2@Fe3O4 was used three times. The particles were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photo-electron spectroscopy; the magnetic properties were measured by PPMS-DynaCool type vibrating magnetometer; the composite showed excellent magnetic response with saturation magnetization of 9.5 emu g−1. Zeta-potential analysis indicated that TiO2 (3.6 mV) and Fe3O4 (− 16.8 mV) are linked by electrical attraction, demonstrating that doping of Fe3O4 is beneficial to the recycle and reuse of catalyst and improves the photo-catalytic efficiency, and TiO2@Fe3O4 is suitable for industrial production.