Preparation of magnetic Fe₂O₃-TiO₂ nanocomposite and its photocatalytic activity under visible light irradition

The composite photocatalysts of Fe₂O₃-TiO₂ were prepared using FeCl₃ and Ti(C₄H₉O)₄ as precursors by sol-gel method. The photocatalysts were characterized by means of X-ray photoelectron spectroscopy(XPS), X-ray diffraction(XRD), scanning electron microscopy(SEM), and energy-dispersive X-ray spectroscopy(EDS), and nitrogen adsorption-desorption isotherms using the Brunauer-Emmett-Teller(BET) method. The results show that the composite consists of pure anatase TiO₂ and Fe₂O₃ with a diameter of about 15 nm. The photocatalytic activity of the Fe₂O₃-TiO₂ composite was confirmed through the photodegradation of methyl blue dye under visible light irradiation(λ>420 nm). The experimental results show that the composite photocatalysts have highly enhanced the photocatalytic efficiency in visible region when compared with each of the two pure semiconductor. The removal rate could reach the highest value under the molar fraction of Fe at 1.0%. More importantly, the magnetic properties are measured using a vibrating sample magnetometer, and the results show that the Fe₂O₃-TiO₂ photocatalyst could be separated from the solution in magnetic field after reaction and then could be recycled.