Synthesis and characterization of mesoporous TiO2 with wormhole-like framework structure Original Research Article

A neutral templating route for preparing mesoporous TiO2 with wormhole-like framework and high surface area is demonstrated based on self-assembly between a neutral amine surfactant (dodecylamine) and a neutral inorganic precursor (tetrabutyl titanate). The effects of the variation of surfactant-to-Ti alkoxide ratio and the aging temperature on mesoporous TiO2 are investigated. Powder X-ray diffraction (XRD) and the transmission electron microscopy (TEM) measurements have been used to characterize the mesostructure that forms at room temperature as well as the calcined materials. The XRD patterns and the TEM images confirm that these materials have the disordered hexagonal wormhole-like topology. The thermogravimetric analysis (TGA) showed that the ethanol extraction is an efficient approach to remove the surfactant template. The pore diameters and the surface areas of materials, evaluated from the N2-sorption isotherms, indicate average pore diameters of about 3.0 and 5.0 nm, and surface areas about 246 and 124 m2/g for calcination at 300 and 350 °C, respectively. The mesoporous TiO2 is formed due to the presence of the hydrogen-bonding interactions between neutral template and inorganic precursors, which are supposed to self-assemble around the surfactant head groups.