Structure and photocatalytic properties of sintered TiO2 nanotube arrays
Abstract
One-dimensional (1D) TiO2 nanotubes perpendicular to the substrate were obtained by electrochemical oxidation of titanium foil in an acid electrolyte. In order to alter the crystallinity and the morphology of films the as-anodized amorphous TiO2 nanotube films were sintered at elevated temperatures. The evolution of the morphology was visualized via scanning electron microscopy (SEM), while the crystalline structure was investigated by X-ray diffraction (XRD) and Raman spectroscopy. The chemical composition was studied by X-ray photoelectron spectroscopy (XPS). The effects of crystallinity and morphology of TiO2 nanotube (NTs) films on photocatalytic degradation of methyl orange (MO) in an aqueous solution under UV light irradiation were also investigated. The TiO2 nanotubes sintered at 650 °C for 30 min had the highest degree of crystallinity and exhibited the best photocatalytic activity among the studied TiO2 nanotube films.