Facile synthesis of monodispersed nanocrystalline anatase TiO2 particles with large surface area and enhanced photocatalytic activity for degradation of organic contaminant in wastewaters

Monodispersed nanocrystalline anatase TiO2 particles have been successfully synthesized via a facile hydrothermal process, combined with encircling hexamethylenetetramine protectors. The products are characterized in detail by X-ray diffraction, Raman spectra, and transmission electron microscope. Experimental results indicate that the catalysts possess monodispersed nanocrystalline anatase structure with small particles (∼6 nm) and large surface area (286 m2 g−1), which are attributed to encircling hexamethylenetetramine protectors for inhibiting the undesirable grain growth. The obtained monodispersed nanocrystalline anatase TiO2 particles exhibit better photocatalytic activity than that of Degussa P25 TiO2 for degradation of highly toxic 2,4-dichlorophenol in wastewaters under UV irradiation, which is ascribed to the small particle size and large surface area offering more active sites, and the improved crystallinity in favor of the separation of photogenerated electron–hole pairs.

► Monodispersed nanocrystalline anatase TiO2 was synthesized via the hydrothermal method.
► They possess uniform small particle size of 6 nm and large surface area of 286 m2 g−1.
► They exhibited better photocatalytic activity than that of commercial P25 TiO2.