Microemulsion Synthesis Of Nano The Znco <sub> 3 </ Sub>, Of Zno

This thesis studied on the preparation, characterization and capability of nanosized zinc carbonate and zinc oxide. Using microemulsion method, we synthesized nanosized zinc carbonate and zinc oxide, which were characterized for the morphology, size and particle size distribution etc. The kinetic parameters of thermal decomposition reaction of nanosized zinc carbonate were determined, while the absorptivity of ultraviolet and visible light of nanosized zinc oxide in aqueous solution was studied.The microemulsion system has been chosen that consisted of CTAB/butanol/ octane/saline solution. The influences of the concentration of the surfactant and reactant on the diameter of nanoparticles were studied and the kinetic parameters of thermal decomposition reaction were determined. It can be shown from experimental results, the diameter of the droplet in the W/O microemulsion which have dissolved reactant zinc nitrate and sal volatile is between 4.9 nm and 7.7 nm, 6.2 nm and 12.4 nm, respectively. Nanosized zinc carbonate prepared by the method of microemulsion has shown good dispersion, narrow distribution and light agglomeration. The particle size of nanosized zinc carbonate is between 5 nm and 40 nm, and its kinetic parameters of thermal decomposition reaction-activation energy E and reaction order n are 110 kJ.mol-1 and 0.9, respectively.Nanosized zinc oxide was obtained by decomposing nanosized zinc carbonate that had been prepared. XRD showed that the data of the product accorded with those of JCPDS card of hexagonal zinc oxide. TEM showed that the prepared zinc oxide particles with diameter in the range of 5 ?40 nm had good dispersion, light agglomeration and uniform distribution. It was showed from the determinable results of the size distribution that nanosized zinc oxide had narrow distribution. The experimental facts indicated that the microemulsion method has its particular merits in the aspect of preparing nanosized particles.This thesis finally studied on the absorptivity of ultraviolet and visible light of nanosized zinc oxide in aqueous solution. The experimental results showed that nanosized zinc oxide has the particular optical performance, namely it has good transparency in visible light zone, and exhibits strong wide band absorption in ultraviolet zone, especially has very strong the capability of absorption to UVA with 360 ~ 380 nm. Using thecharacteristic of strong wide band absorption of nanosized zinc oxide in ultraviolet zone, it can be alone employed as the component of sun-screening agent to protect the skin by efficiently absorbing the ultraviolet ray.