The ZnO-Ag core-shell nanoparticle in ethanol was prepared by photoreduction and colloidal methods. The experimental results obtained from the absorption spectrum, fluorescence spectrum and electron microscopy revealed that the structure of the hybrid particle is ZnO core covered with Ag. The thickness of silver layer formed on ZnO core can be controlled by the concentration of Ag+ and the time of UV irradiation.In addition, the electrical properties of the charge double layer of the ZnO particle greatly affect the formation of ZnO-Ag hybrid particle.
The mechanism of the formation of ZnO nanoparticle by mixing zinc acetateand sodium hydrokide in ethanol solution was studied. It has been found that there aretwo patliways to obtain ZnO nanoparticle: one is a fast process which is characterizedby the direct dehydration of Zn(OH)2 when Zn2+ is in excess; another is a slow processwhich is featured by the formation of [Zn(OH)4]2- complex and the subsequent nucleationof ZnO particle when OH- is in excess.
