The Morphology and Evolution of Zinc Oxide Flowers Like by Direct Synthesis and Sequential Nucleation Growth
N. Elizondo, R. Obregon, E. Perez
University of North Texas, US
Keywords: zinc oxide, flowers, synthesis, morphology
Abstract:The morphology evolution characteristics of ZnO nanostructures were systematically studied from dense rods to ZnO flowers like. The ZnO flowers like were prepared by direct decomposition of a Zn(OH)42– precursor. Zinc oxide with a diversity of well-defined morphologies was synthesized. Flowerlike ZnO built up by nanorods was obtained by treating Zn(OH)42– precursor in an aqueous solution. The sequential nucleation growth method consisted of a multistep synthesis of complex nanostructured films. It begins with substrate preparation for heterogeneous nucleation of oriented nanocrystals by seeding the substrate with nanoparticles of the desired film material. New crystals grew on the surfaces of the primary rods when bifunctional diaminoalkane molecules were added to the solution. Systematical condition-dependent experiments were compared comprehensively to reveal the formation and detailed growth process of ZnO nanosized crystallites and aggregates; this imposes an effect on the morphology evolution. The experimental results studied by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy indicated that the precursor, solution basicity, and reaction temperature and pressure as well as time were responsible for the variations of ZnO morphologies. High-quality crystallinity and orientational alignment, are all important for efficient electron and photon transport in applications such as photovoltaics and lasers.