Surfactant-free precipitation synthesis, growth mechanism and photocatalytic studies of ZnO nanostructures

Different morphologies of ZnO nanostructures such as spherical-like, rod-like and flower-like were successfully synthesized by a facile and surfactant-free precipitation method in different NaOH concentrations. The as-synthesized ZnO nanostructures were characterized by field-emission scanning electron microscopy, energy dispersive X-ray, X-ray diffraction and fourier transform infrared spectroscopy. The results showed that the as-synthesized ZnO nanostructures were wurtzite hexagonal phase pure ZnO and well crystalline. It was also observed that the spectral properties of the as-synthesized ZnO nanostructures can be altered at different NaOH concentrations. A possible formation mechanism of the different ZnO nanostructures was discussed in term of the crystal nucleation and crystal growth direction. The photocatalytic tests revealed that the as-synthesized ZnO nanostructures were promising photocatalysts in remediation of water contaminated of organic pollutants under UV light irradiation.