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 ...