| With the rapid progress of the science and technologies, it is extremely strict for the qualities of the traditional ZnO products, so nanometer zinc oxide is the sequence of upgrading products. Nanometer zinc oxide is the functional material with manifold excellent performances and wide spread applications. In this paper, it is reviewed the present situation and the latest research progress in the preparation and application technology of nanometer zinc oxide.In this paper, firstly, according to the theoretical analysis and experimental study, the mechanism for structure and morphology control of ZnO nanoparticles prepared by homogeneous precipitation was revealed, and the temperature, agitation, feeding materials and preventing aggregation methods were investigated. The urea was used as precipitant agent and reacted with soluble Zn2+ salt solution to prepare nanometer ZnO by homogeneous precipitation method. Zinc nitrate was the best starting material of all the soluble Zn + salts. The optimum process conditions selected by orthogonal test were found as follows: molar ratio of CO(NH2)2 and Zn(NO3)2 3.5 : 1, reaction time 1.0h, reaction temperature 105℃, yield 93.80% and particles size range 11~17nm.Epitaxy of ZnO nanocrystals was prepared by homogeneous precipitation using urea and zinc nitrate as the starting materials. It was proposed that the growth units and epitaxy mechanism of ZnO nanocrystals from the view point of crystal chemistry. The epitaxy is more easily to occur along c axis, which is primarily formed by the connection of positive hexagonal cone faces p{1011} and negative hexagonal cone faces p' {1011}, secondly by the positive polar faces c(0001) and negative polar faces c(0001).When there is a higher than 9.5 pH value, the Zeta potential is higher than 30mV, and the stability of ZnO nanoparticles becomes better. During these processes, the dispersant of A and PA is more excellent than PEG and PVA.
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