Controllable synthesis of nanostructured TiO2 by CTAB-assisted hydrothermal route

In this study, steerable nanosized TiO2 was prepared by a novel and facile cetyltrimethyl ammonium bromide (CTAB)-assisted hydrothermal process. Different from traditional hydrothermal methods, diverse amounts of CTAB and TiO2 nanopowders were added into a NaOH aqueous solution for hydrothermal reaction. The products were characterized by thermogravimetric differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), transmission electron microscopy ITEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and N-2 adsorption-desorption. The results show that adding 0.04 mol L-1 CTAB in the hydrothermal reaction contributes to the efficient preparation of TiO2 nanotubes. It is found that the length of TiO2 nanotubes can be tuned from 50 nm to several hundred nanometers by simply adjusting the CTAB concentration from 0.01 to 0.04 mol L-1. It is noteworthy that the as-prepared TiO2 consists of nanosheets with the further increased amount of CTAB to 0.2 mol L-1. Furthermore, the possible formation mechanism of nanosized TiO2 with controllable morphology obtained from the CTAB-assisted hydrothermal method was also proposed.