Shape-Controlled Synthesis of Zinc Oxide Microcrystals via a Simple Solvothermal Process and Their Optical Properties

Abstract

In this work, the synthesis of zinc oxide (ZnO) microcrystals on a large scale with novel twinned ice-cream cones morphology without any additives have been synthesized with a facile alcohol-thermal method. It was found that other morphologies of ZnO (single ice-cream cones, dumbbell-like, hamburger-like and doughnuts-like microcrystals, etc.) could also be readily obtained by adjusting addition amount of ZnO precursor, temperature, solvent composition and surfactant. Furthermore, ZnO twinned microtubes with one end open were obtained using the mixed water and ethanol as solvent by the help of cetylpyridinium bromide (CPB). X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy(TEM), selected area electron diffraction (SAED), and the photoluminescence (PL) spectroscopy were used to characterize these products. Photoluminescence results showed that the as-synthesized ZnO microcrystals presented a narrow and sharp UV emission at 390 nm and a broad blue–green emission at above 466 nm when excited by UV light.