Template-free synthesis of uniform TiO2 mesoporous microspheres with enhanced photocatalytic activity

TiO2 mesoporous microspheres assembled from uniform nanoparticles were successfully synthesized by a template-free hydrothermal method with acetic acid (HAc) and H2O using tetrabutyl orthotitanate (TBOT) as a precursor. The morphology, crystal structure, surface area, and photocatalytic activity of the as-prepared TiO2 were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), N2 adsorption-desorption analysis, and UV-visible diffuse reflectance spectroscopy. The characteristics of obtained products included a good crystalline anatase phase, higher surface area and stronger absorption to UV light wavelength than Degussa commercial P25. Moreover, the cationic rhodamine-B (RhB) dye is used as the target pollutant to characterize the adsorption performance and photocatalytic activities. Photocatalytic measurements show that mesoporous TiO2 microspheres exhibit improved photocatalytic activity of RhB compared with Degussa commercial P25 photocatalyst.