Structural and Optical Properties of Well-Aligned ZnO Nanorod Arrays Grown by a Hydrothermal Method

Abstract

In this paper, vertically aligned ZnO nanorod arrays were synthesized by a simple hydrothermal process. The microstructure, morphology and optical properties of the as-prepared samples were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence spectrum (PL). The results show that the vertically aligned ZnO nanorod arrays are hexagonal wurtzite structures with the high (002)-orientation. At room temperature, the PL measurements illustrate that the as-prepared ZnO nanorod arrays exhibit a strong ultraviolet (UV) emission centered at about 378nm and a broad yellow-green emission centered at about 554 nm. A possible origin of the yellow-green emission of the ZnO nanorod arrays related to the intrinsic defect is proposed.