Preparation of TiO₂ Nanotube Arrays by Anodic Oxidation and Its Characterization

TiO2 nanotube array film was prepared on the surface of pure Ti by anodic oxidation. The effects of anodic oxidation time, oxidation voltage and annealing on the morphology and structure of the TiO2 nanotube were investigated by means of XRD and FESEM. Mechanism of the formation of nanotube arrays were discussed. The results show that ordered TiO2 nanotube array film could be prepared on the surface of pure Ti by this method. With increase of the oxidation voltage, the diameter of the nanotube increased, and tubular characteristics was obvious. With prolongation of the oxidation time, the nanotube size was more uniform and arranged more regular. Before annealing, the nanotubes were amorphous state; after annealing at 450 ℃, most of the TiO2 was anatase phases with little rutile phases.