Novel horseshoe-shaped ZnO nanorods and their optical properties

Large areas of ZnO horseshoe-shaped nanorods have been fabricated vertically on MgO-coated Si (1 1 1) substrates by chemical vapor deposition method. The well-aligned nanorod arrays were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscope (HRTEM), energy-dispersive X-ray spectroscopy (EDS), and photoluminescence spectroscopy (PL). The results show that the nanorods are perfect single crystals with hexagonal wurzite structure along the [0 0 0 1] growth direction. The nanorods have regular horseshoe shape, and the diameter of the rods rang 70-99 nm while the length is about 600 nm. The PL spectrum exhibits a strong peak at 500.8 nm and two relatively weak emission bands centered at 387.7 nm and 648.6 nm, which indicates that the ZnO arrays are of excellent optical quality. (C) 2011 Elsevier B.V. All rights reserved.