【作者】 童长钿；

【导师】 张多默； 胡新；

【作者基本信息】 中南大学 ， 冶金工程， 2004， 硕士

【摘要】 纳米氧化锌由于具有许多宏观材料所不具有的特殊性质，在磁、光、电、敏感、抗菌消毒、紫外线屏蔽等方面具有普通氧化锌产品所不具备的特殊性能和用途，展示出引人注目的应用前景。 论文基于沉淀法制备纳米粒子的化学原理，进行了单分散体系的设计，分析总结了控制反应温度、搅拌条件、加料方式和防止团聚的措施，提出了采用尿素均匀沉淀法制备出粒径可控的单分散ZnO纳米粒子。用正交设计实验对反应物配比、反应温度、反应时间等条件进行了考察，筛选出最佳工艺条件：尿素与硝酸锌的物质的量比为3.5：1；反应温度为105℃；反应时间为1.0小时，0.5gPVP和1.0g六偏磷酸钠作分散剂，这些结果为纳米ZnO的工业化生产提供了基础数据。以Zn₄CO₃（OH）₆·2H₂O为原料，采用水热法制备了氧化锌纳米晶粒。从结晶化学角度提出了晶粒的生长基元和取向连生机理，认为氧化锌晶粒取向是沿着晶轴c方向易于晶粒连生，它是由正、负六方锥面p{1011}，p{1011}面相互联结为主，其次为正、负极面c（0001）与-c（0001）。 纳米ZnO在pH值＞9.5时，其Zeta电位超过30mV，体系的稳定性提高；电解质聚合物A和PA分散ZnO的能力比非电解质聚合物PEG和PVA效果好；A分散剂的分子量影响其分散性能，低分子量有利于纳米ZnO在水中的分散；经纳米ZnO微乳液整理的涤棉织物，其紫外透过率远远低于未经整理的涤棉织物；UPF指数也超过50，具有极佳的抗紫外防护能力。更多还原

【Abstract】 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.更多还原