The physicochemical properties of nanomaterials depend on their size and shapes which are key factors for various biomedical applications. ZnO nanostructures were prepared with various shapes including nanospheres, nanoplates, and nanopyramids using hydrothermal method. ZnO nanoparticles (NPs) have antibacterial properties against Escherichia coli (E. coli) bacteria, and they have the ability to control or destroy them. Physicochemical properties of the prepared nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible absorption spectroscopy (UV-Vis), and photoluminescence spectroscopy (PL). XRD analysis confirmed that formation of the wurtzite phase of zinc oxide NPs and PL results revealed low structural defects of the produced NPs. Antibacterial activity of the produced nanostructures was probed against gram-negative E. coli bacteria. The results of antibacterial experiments exhibited that ZnO nanopyramids prepared at temperature of 70 °C have a more inhibitory effect than nanospheres and nanoplates. These indicate that the antibacterial activity of ZnO NPs depends on the morphology and shape in addition to concentration of the nanomaterial.
