Effects of the Structure of TiO[sub 2] Nanotube Array on Ti Substrate on Its Photocatalytic Activity

Abstract

A novel oriented TiO 2 nanotube ͑TN͒ array on Ti substrate was fabricated by using an electrochemical method. The structure and surface morphology of the TN array was examined by Raman spectroscopy and scanning electronic microscopy, respectively. The photocatalytic activity of the TN arrays was evaluated by the removal of methylene blue in aqueous solution. The effects of structure and morphology of the TN array on its photocatalytic activity were investigated. It was observed that the crystal structure, morphologies, and nanotube sizes were greatly influenced by anodization voltage and calcination temperature. The shift of absorption edges shorter wavelengths were ascribed to the quantum effect of the tube wall thickness. The TN arrays prepared at 20 V and calcined at 450°C have the highest photocatalytic activity due to an increase in the anatase crystal phase and an increase in surface area. When the calcination temperature was higher than 450°C, the photocatalytic activity of the TN array decreased, which was ascribed to excessive rutile content and a decrease in surface area resulting from the sintering and growth of TiO 2 crystallites.

One-Dimensional Titanium Dioxide Nanomaterials: Nanotubes

“…First experiments were carried out for tubes grown in aqueous electrolytes 671,[679][680][681] and it was observed that they may be more efficient than comparable Degussa P25 layers 671 .…”

Toward tailored functionality of titania nanotube arrays: Interpretation of the magnetic-structural correlations

“…6,7 Thus, investigation of these properties is anticipated to lead to a better understanding of factors promoting higher photocatalytic efficiencies. [8][9][10] In this study, ordered arrays of amorphous titania NTs are synthesized by room-temperature electrochemical anodization of titanium foil in the presence of fluorine ions, followed by elevated-temperature crystallization treatments (200-450°C) in oxygen-rich (O 2 ), oxygen-deficient (Ar) and reducing (H 2 ) environments, to modify the NTs' crystal structure, morphology and electronic properties. The crystal structure, morphology and magnetic properties of the NTs in their as-anodized and annealed states were examined by x-ray diffractometry (XRD), scanning electron microscopy (SEM) and superconducting quantum interference device (SQUID) magnetometry.…”

Formation of porous anodic titanium oxide films in hot phosphate/glycerol electrolyte

“…Self-organized porous anodic titanium oxide films have attracted much attention mainly due to their wide potential applications, including dye-sensitized solar cells [1][2][3], photocatalysis [4][5][6][7][8][9][10][11], self-cleaning, electrochromism, sensors [12][13][14] and biomedical application [15]. The porous anodic titanium oxide films, usually with nanotubular structures, are formed in fluoride-containing 3 electrolytes [16,17].…”