Fabrication of silica nanotubes using Sb 2 Te 3 nanowires as templates

In this study, a simplified fabricating method of silica nanotubes using nanowires as templates was introduced. First, the templates were prepared with catalyst-free Sb2Te3 nanowires from Al:Ge:Sb:Te thin film by annealing at 300°C in N2 gas atmosphere. Second, they were deposited with Si using DC magnetron sputtering and then annealed at 500–800°C in N2 gas atmosphere. The annealing process vaporized the core Sb2Te3 nanowires and oxidized the outer Si wall, so that the amorphous silica nanotubes were produced. The dimensions of silica nanotubes were measured as ~150nm in the outer diameters and ~30nm in the wall thickness. We found that the contents of trace elements, which remained in the silica nanotubes, were dependent on the annealing conditions such as the temperature and duration time.