Controlled synthesis of porous flower-like TiO2 nanostructure with enhanced photocatalytic activity

Flower-like TiO2 nanostructures were successfully synthesized via the urea homogeneous precipitation method using (NH4)2TiF6 as a titanium source in aqueous solution. This approach was simple, environmentally friendly and without using template. The flower-like TiO2 nanostructures were characterized in detail with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV–vis spectrum, respectively. The flower-like TiO2 nanostructures, with diameters ranging from 150–300 nm, were assembled by primary nanoparticles and the length of the petals was approximately 60 nm. Interestingly, the surface of the flower-like TiO2 nanostructures appeared to have many pores with diameters of 10–13 nm after the sample being calcined at 550 °C, while the morphologies and sizes of the TiO2 samples did not change. The photocatalytic activity of the as-prepared samples was evaluated by photo-degradation of rhodamine B (RhB) from aqueous solution at ambient temperature. The flower-like porous TiO2 samples exhibited much higher photocatalytic activity than the flower-like TiO2 samples. All these advantages showed a bright future for this flower-like porous photocatalyst in environmental protection.