Hydrothermal synthesis of TiO2 nanotubes from one-dimensional TiO2 nanowires on flexible non-metallic substrate

TiO2 nanotubes (NTs) immobilized on carbon fibers (CFs) were successfully prepared by a hydrothermal synthesis method based on alkali treatment of TiO2 nanowires (NWs). The as-prepared CFs with TiO2-NTs (CFs/TiO2-NTs) were characterized with a field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectrometer (XPS), and Xray diffractometer (XRD). The images on FESEM and TEM show that the entire surfaces of CFs are covered by TiO2-NTs with the thickness of ca. 7.4 pm. The inner and outer diameters of TiO2-NTs are ca. 4.6 and 8.7 nm, respectively. The analyses with EDS and XPS indicate that the main elements on the surface of CFs/TiO2-NTs are C, O, and Ti. According to the analysis with XRD, the transformation from titanate NTs to anatase TiO2-NTs was realized after annealing treatment. This work may provide a novel method for immobilizing TiO2-NTs on flexible non-metallic substrates.