Growth and spectral analysis of ZnO nanotubes

ZnO nanotubes were fabricated by vapor-phase transport using the mixture of ZnO and graphite powders in air. A self-catalyzed growth mechanism was proposed based on microstructure analysis by scanning electron microscopy, transmission electron microscopy, and x-ray diffraction. Raman scattering, integrated photoluminescence, and time-resolved photoluminescence were employed to explore the optical properties and the dynamic process. Combing with crystal structure and the spectral characteristics of the ZnO nanotubes, the charge carrier transport process was discussed.