Synthesis of size-tunable mesoporous anatase titania spheres by a template-free method

A facile route was presented to fabricate mesoporous anatase titania spheres at low temperature; the titania precursor sphere was prepared through a template-free process and then treated by the boiling water. X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM) were adopted to characterize the morphology and crystal structure of the products. The adsorption properties and photocatalytic activities were also investigated. The results indicated that the porous structure and anatase nanocrystals were gradually formed from the surface to the interior of the titania precursor spheres with increasing treatment time. Moreover, there was little change in the size of the spheres during boiling water treatment, thus the size of the mesoporous anatase titania spheres could be easily tailored by controlling the diameter of precursor spheres. The as-prepared product showed excellent adsorption capacity and photocatalytic activity than the commercial P25 due to its high specific surface area.