Controlling the Morphology of Polymeric Precursor-Derived ZnO Flower-Like Structures

Authors

  • Uma Choppali,

    Corresponding author
    1. Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76203
      †Author to whom correspondence should be addressed. choppali@unt.edu
    Search for more papers by this author
  • Brian P. Gorman

    1. Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76203
    Search for more papers by this author

  • L. Klein—contributing editor

†Author to whom correspondence should be addressed. choppali@unt.edu

Abstract

The study of the mechanisms of formation and growth of ZnO nanostructures is crucial as they have the potential to find applications in opto-electronic devices. ZnO nanostructures of different morphologies have been synthesized using a low-temperature polymeric precursor process. Controlling the Zn cation and nitric acid concentrations, flower-like morphology of the ZnO nanostructures could be synthesized with excellent reproducibility. Besides chemistry, the effects of spin-coating variables on morphology were also investigated. The results show that the morphology of the flowers is controlled by Zn2+ ion concentration, whereas spin speed and film thickness are responsible for the size variations. All obtained ZnO structures reveal a polycrystalline hexagonal wurtzite structure and strong UV photoluminescence along with lattice defects. Polar surfaces of ZnO promoting multilayer Volmer–Weber growth play a crucial role in the development of these flower-like structures. Possible mechanisms for variations of morphology with synthesis parameters are discussed.

Ancillary