Mesoporous TiO2 with wormlike structure synthesized via interfacial surfactant assisted route

A novel route to prepare mesoporous TiO2 with wormlike structure is developed via hydrolysis of titanium isopropoxide (TIP) with the surfactant (EO)20-(PPO)70-(EO)20 (P123) and with the aid of supercritical (SC) CO2 at the interface of SC CO2 and an aqueous solution. Our experimental results demonstrate that the surfactant P123 and SC CO2 play an important role in synthesizing mesoporous TiO2 because the surfactant P123 can take up directing function and SC CO2 can reduce the TIP hydrolysis reaction rate, both of which are in favor of preparing mesoporous TiO2. The resultant TiO2 products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen sorption measurements. Nitrogen analysis reveals that the mesoporous TiO2 presents high surface area (as) of 494.2 cm2/g in comparison with the TiO2 particles (as = 202.4 m2/g) and microspheres (as = 28.6 m2/g) obtained in our work. Furthermore, the mesoporous TiO2 exhibits a considerably high photocatalytic oxidation of 2-propanol applying a 200-W high-pressure Hg lamp (340 nm) as irradiation due to its high surface area.