A novel protocol toward perfect alignment of anodized TiO₂ nanotubes

A novel protocol toward the perfect alignment of nanotubes (NT) with very-high aspect ratios by a two-step anodization process has been reported. The phase identification and the surface-structure characterization of the samples were conducted using X-Ray Diffraction (XRD) and and Field Emission Scanning Electron Microscopy (FESEM). Highly ordered TiO2 NT arrays were prepared by a potentiostatic anodization in a two-electrode electrochemical cell. The NT in the first anodization can be readily peeled off, leaving ordered footprints of NT on the surface of the Ti substrate. The well-aligned NT can be used as effective templates for electrodeposition of high-aspect-ratio metal nanowires, which are otherwise impossible to achieve via conventional NT. The approach represents a key addition to TiO2 NT production, and have strong application potentials.