ZnO micro-flowers were successfully synthesized by precipitation method via an ammonical ammonium carbonate zinc aqueous solution in presence of oleic acid. Oleic acid as additive could affect on morphology and photo-catalysis properties of ZnO particles. The structure and morphology of products were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), UV- visible spectroscopy, Raman spectroscopy and Photoluminescence (PL) analysis. ZnO with flower like morphology exhibited improved ability on the photo-catalytic degradation of Methyl Blue (MB) dye wastewater compared with sphere like nano particles under UV radiation. The higher photo-catalytic activity of the ZnO micro-flowers result from the larger content of oxygen vacancy on the surface of nano-materials as revealed by their Raman and Photoluminescence (PL) spectra features.

Keywords: ZnO, Nano-structured, Photo-catalysis, Precipitation method.