Preparation And Characterization Of Zno Nanomaterials

For the physical and chemical properties of material closely related to the size and shape of their particles, the monodispersed nanomaterials have caused great attention in recent years. As a kind of wide band-gap semiconductor, nano-structured ZnO show novel properies, which make ZnO a kind of promising material widely used in photoelectric devise, catalysis, rubber, ceramic and make-up industry. With the increasing concern on the preparation process and properties of ZnO with different size and shape, and the faster development on it's applications in various field, monodispered ZnO nanomaterial have received more and more intensive interests.In this paper, we gave a primary introduction about monodisperse nanoparticles and situation of nano-structured ZnO at present, which followed by demonstration of different-shaped ZnO made by sol-gel and thermal decomposition method. The results present ZnO with sphere, rod, diamond and hexagonal shape. With the help of X ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM) and photoluminescence (PL), can we check the properties and analyses the mechanism of the material, the out-coming are as follows:(1) Monodisperse ZnO nanoparticles with size around 5nm made by sol-gel method combined with large power ultrasonic, and ethanol solution contained Zn(AC)2 and LiOH worked as reaction agent. We demonstrate the acceleration effect on nucleation and the reason for it, analyses how these parameter such as pH value, mol proportion and the power of ultrasonic affect on the result on the rate of precipitation and size distribution.(2) Using these monodisperse ZnO nanoparticles made by sol-gel method as seeds, varying reflux times and temperature, we get ZnO nanorods of different dimension. We analysed these ZnO nanorods to make clear the mechanism of growth and applied BFDH and HP method on crystal growth. Based on BFDH and HP model, we simulated the ideal shape consisted with experimental results, which gave thereasonable explanation of mechanism of ZnO nanorods from energy perspective.(3) We get ZnO particles with different shapes through thermal decomposition method. Besides analysis of some parameters such as time, temperature, surfactant have great impact on the result. BFDH and HP method was also used to give an understanding about the mechanism of these different-shaped ZnO particles.