Large-scale and low-temperature synthesis of maize-shaped ZnO micron flowers with excellent optical properties

An experimental procedure is presented for synthesis of maize-shaped single-crystal ZnO flowers on a large scale at 60 °C for 24 h. The morphologies, purity, sizes and optical properties of the products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), standard selected area electron diffraction (SAED), Raman, UV-vis absorption and PL spectra. XRD measurement proved the formation of ZnO with wurtzite structure. The results from SEM and TEM revealed that two types of maize cob-based micro-flowers with diameter of 1-2 (mu)m were produced. SAED patterns confirmed that the product was single crystal. UV-vis absorption and PL measurement demonstrated a high quality of the products. The possible growth mechanism is also discussed.