Morphology study of 1D ZnO nanorods

Abstract

Four kinds of new one-dimensional nanostructures, celery-shaped nanorods, needle-shaped nanorods, twist fold-shaped nanorods, and awl-shaped nanorods of ZnO, have been grown on single silicon substrates by an Au catalyst assisted thermal evaporation of ZnO and active carbon powders. The morphology and structure of the pre- pared nanorods are determined on the basis of field-emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD). The photoluminescence spectra (PL) analysis noted that UV emission band is the band-to-band emission peak and the emission bands in the visible range are attributed to the oxygen vacancies, Zn interstitials, or impurities. The field-emission properties of four kinds of ZnO nanorods have been invested and the awl-shaped nanorods of ZnO have preferable characteristics due to the smallest emitter radius on the nanoscale in the tip in comparison with other nanorods. The growth mechanism of the ZnO nanorods can be explained on the basis of the vapor–liquid– solid (VLS) processes.