Facile synthesis of nano-sized ZnO by direct precipitation method

In this contribution we are presenting a simple precipitation method to synthesize zinc oxide (ZnO) nanoparticles using zinc nitrate and urea in aqueous solution. The obtained precipitated compound was calcined and structurally characterized by Powder X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and UV-Vis spectroscopic techniques. The powder X-ray data indicates that the calcined compound exhibits hexagonal (Wurtzite) structure with space group of P63mc (No. 186). The thermal behavior of as-prepared compound was examined and it indicates that there is no further mass loss above 450 °C. Scanning electron micrographs show uniform spherical like morphology of ZnO. The TEM results reveal that the particle sizes were in the order of 30–50 nm and the average particle size is around 35 nm. The FT-IR result shows the existence of OH, NO2 , CO, CO2 groups in uncalcined sample. The band gap was higher for synthesized ZnO particles than their bulk counterparts. The results indicate that urea is an attractive material that can be used as precipitation agent for preparing ZnO.