Controllable preparation of TiO₂ nanotube arrays on Ti foil substrates

TiO₂ nanotubes were prepared by anodic oxidation method using HF electrolyte solution and NH₄F electrolyte solution on the titanium foil substrate. The morphology and crystal structures of the nanotube arrays were characterized. The structures of TiO₂ nanotube arrays prepared by HF acid aqueous solution are not clear and regular. However, TiO₂ nanotube arrays prepared by NH₄F / organic ethylene glycol electrolyte are more orderly and clear. By controlling the composition of the electrolyte, anodic oxidation voltage and anodization time parameters, TiO₂ nanotube arrays with a highly ordered and controllable process were obtained on the Ti foil substrate.