EDTA-assisted fabrication of TiO2 core–shell microspheres with improved photocatalytic performance

Three dimensional (3D) TiO2 core–shell microspheres were successfully synthesized by a one-step hydrothermal method using ethylenediaminetetraacetic acid (EDTA) as the assistant agent. The sample was characterized by XRD, EDX, SEM, TEM, and BET. The photocatalytic activity of TiO2 core–shell microspheres for the degradation of methyl orange (MO) aqueous solution was measured by UV–vis absorption spectroscopy. The XRD result shows that the TiO2 core–shell microspheres are crystalline without further sintering treatment. Furthermore, the core–shell microspheres exhibit higher photocatalytic activity than that of commercial TiO2 (Degussa P25) for oxidation of MO under UV light irradiation. The enhanced photocatalytic activity is due to the high BET surface area of the sample, which might possess more surface reaction sites and can adsorb and transport more dye molecules.