Titanium oxide nanotubes, nanofibers and nanowires

A simple one-step hydrothermal reaction among TiO2 powders and alkaline solution has been developed to synthesize low-dimensional titanate nanostructures. The morphologies of the obtained nanomaterials depend on the process parameters: the structure of raw material, the nature and concentration of alkaline solution, reaction temperature and time, which suggests that the nanostructure synthesis could be controllable. Trititanate nanotubes with the diameters of about 10 nm were synthesized via the hydrothermal reaction of TiO2 crystals of either anatase or rutile phase and NaOH solution in the temperature range of 100–160 °C. Nanofibers with an interlinked structure were formed when amorphous TiO2 or commercial TiOSO4 was treated with NaOH at 100–160 °C. Pentatitanate nanoribbons with high aspect ratio were obtained by autoclaving of either crystalline or amorphous TiO2 in NaOH solution at the temperature above 180 °C. Octatitanate nanowires with the diameters of 5–10 nm were prepared from TiO2 particles treated with KOH solution. These nanostructures were analyzed by a range of methods including powder X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), energy-dispersive X-ray spectroscopy (EDX) and infrared spectroscopy (IR).