Preparation of CuCrO₂ Hollow Nanotubes from an Electrospun Al₂O₃ Template

A hollow nanostructure is attractive and important in different fields of applications, for instance, solar cells, sensors, supercapacitors, electronics, and biomedical, due to their unique structure, large available interior space, low bulk density, and stable physicochemical properties. Hence, the need to prepare hollow nanotubes is more important. In this present study, we have prepared CuCrO₂ hollow nanotubes by simple approach. The CuCrO₂ hollow nanotubes were prepared by applying electrospun Al₂O₃ fibers as a template for the first time. Copper chromium ions were dip-coated on the surface of electrospun-derived Al₂O₃ fibers and annealed at 600 °C in vacuum to form Al₂O₃-CuCrO₂ core-shell nanofibers. The CuCrO₂ hollow nanotubes were obtained by removing Al₂O₃ cores by sulfuric acid wet etching while preserving the rest of original structures. The structures of the CuCrO₂-coated Al₂O₃ core-shell nanofibers and CuCrO₂ hollow nanotubes were identified side-by-side by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. The CuCrO₂ hollow nanotubes may find applications in electrochemistry, catalysis, and biomedical application. This hollow nanotube preparation method could be extended to the preparation of other hollow nanotubes, fibers, and spheres.