Controllable synthesis of nanostructured TiO2 by CTAB-assisted hydrothermal route

Abstract

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 (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and N₂ 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.