【作者】 朱钰方；

【导师】 张少明； 方莹；

【作者基本信息】 南京工业大学 ， 材料学， 2003， 硕士

【摘要】 纳米ZnO是近年来发现的一种高新技术材料，是极少数几种可以实现量子尺寸效应的氧化物半导体材料。由于氧化锌粒子的超细化，使其在磁、光、电敏感材料等方面呈现出常规材料所不具备的特殊性能，因而具有广阔的应用前景。如制造气体传感器、荧光体、紫外线屏蔽材料、雷达吸波材料、高效催化剂等等。 目前，世界各国对纳米氧化锌的研究主要包括制备、微观结构、宏观物性和应用等四个方面，其中制备技术是关键，因为制备工艺过程与控制对其微观结构和宏观物性具有重要的影响。 本文用室温固相反应和液相法（直接沉淀法）制备纳米氧化锌，对其工艺进行系统的比较研究，并对所得粉体进行全面的表征，从中寻求一种简单有效、重复性好的制备工艺，合成出粒径小于50nm且分散性好的ZnO纳米粉体，为ZnO粉体的应用奠定基础。 首先根据固相反应条件，选择不同的反应体系进行实验研究，从而确定较好的固相反应体系为Zn（NO₃）₂·6H₂O+Na₂CO₃。针对此反应体系，通过XRD分析研究反应过程，发现反应物的扩散过程是整个固相反应的控制阶段。通过粒度、比表面积、XRD、SEM、TEM、FT—IR以及TG—DTA等现代测试手段对制备过程分析研究，得到固相法制备ZnO纳米粉体的最佳工艺条件为：在室温下，Na₂CO₃和Zn（NO₃）₂·6H₂0按1.50左右摩尔比混合研磨30min后移入PH值为10.8，已经加入0.5wt％阴离子型表面活性剂的碱性环境中陈化1h，洗涤多次后用无水乙醇淋洗，抽滤后在80℃下干燥，所得前驱化合物以一定升温速度加热至320℃后保温1h。制备工艺的重复性较好，得到的ZnO纳米粉体为六方晶系纤锌矿结构，粒径在10～30nm左右，分散性较好。 通过对Zn（NO₃）₂·6H₂O+Na₂CO₃反应体系进行直接沉淀法制备ZnO纳米粉体的机理探讨，发现该反应是一个一步快速反应过程，整个反应不易控制。运用粒度、比表面积、XRD、SEM、TEM、FT—IR以及TG—DTA等现代测试手段的分析研究表明，直接沉淀法也能制备出六方晶系纤锌矿结构的ZnO纳米粉体，粒径在30～80nm，但分散性、重复性不够理想。较好的工艺条件为：在20 南京工业大学硕士学位论文 摘 要℃下，ZnnyO力X溶液浓度1．50mol／l，并加入0．6w－t％的阴离于型表面活性剂，NazCOz溶液浓度 1刀mol／l，且NaaCO3／ZncyO对拓的摩尔配比为 1．75左右，电动搅拌，恒温反应 1小时左右后在 PH值为 10．8的碱性环境中洗涤多次，无水乙醇淋洗后抽滤，在80”C下干燥，320”C热分解lh。 通过对固相反应方法和直接沉淀法所制备的ZnO纳米粉体的TEMIT—IR。XRD、UV／VIS SpectrUm。粒度、比表面积、吸光度、稳定性分析，结果表明因相反应方法所制备的ZnO粉体的单颗粒粒径小、粒度分布窄、比表面积大、分散性和紫外线屏蔽特性好，因而固相反应制备ZnO纳米粉体要优于直接沉淀法。另外，固相反应方法工艺流程短，设备简单，原料易得，生产成本低廉，为ZnO纳米粉体的产业化提供了一条新的思路。更多还原

【Abstract】 Nanometer ZnO is a kind of high-technology material found recent years ago, and also is quite few kinds of oxide semiconductor materials that can realize the effect of quantum size. With studying deeply on the preparation technology, ZnO particles are becoming more smaller to nano-meter level, Which makes them take on special properties in magnetism, light, electricity sensitivity that regular materials don’t possess. So it can be applied in many fields. Such as gas induce device, fluorescence materials, UV-masked materials, radar absorbing materials, high-effect acceleration agents, and so on.At present, in all the world the study on nano-meter ZnO includes mainly four aspects: preparation, micro-structure, macro-property and applied fields. But the preparation technology is most important, because the study and control on preparation technology and process have important effect on the micro-structure and macro-property.Nano-meter ZnO is prepared by solid state reaction in common temperature and liquid state reaction (direct precipitation method) in this paper. It will study comparatively on the preparation technology systematically and will analyze the prepared powders completely, through which we will find a kind of preparation technology that uncomplicated, effective and good repetition, will gain ZnO nano-meter powders that particle diameter less than 50 nm and disperse well. It will establish applied foundation for ZnO nano-meter powders.Firstly, according to the condition of solid state reaction, we have studied the different reaction systems through experiments and made sure that the optimal solid state reaction system is Zn(NO3)2·6H2O+Na2CO3. To this reaction system, we find that the diffuse course is the control phase of the whole solid state reaction through analyzing the reaction course by XRD. The preparation process was studied by particle size analysis, ratio surface area analysis, XRD, SEM, TEM, FT-IR and TG - DTA advanced examining instruments. The optimal technology condition of preparing ZnO nano-meter powders by solid state reaction was that the Na2CO3 and Zn(NO3)2·6H2O mole ratio is about 1.50, which are blended and grinded for 30min in common temperature, take the mixture into alkalescence washing liquid for 1h whosePH value is 10.8, and have mixed 0.5wt% anion type surfactant and washed several times, after that, washed by ethanol. Then filtrate the suspending liquid, gain precursor and dry them at 80℃. The precursor are decompounded at 320℃ for In. The preparation technology was repeated well, and the ZnO nano-meter powders is hexagonal crystal wurtzite phase, particle size was from 10nm to 30nm, dispersing was good.The preparation mechanism of ZnO nano-meter powders by direct precipitation method to Zn(N63)2·6H2O+Na2CO3 system was discussed that it’s reaction is a one-step speedy reaction course and the whole reaction has difficulty in controlling. It was studied by particle size analysis, ratio surface area analysis, XRD, SEM, TEM, FT-IR and TG-DTA advanced examining instruments. Direct precipitation method can prepare the hexagonal crystal wurtzite phase ZnO nano-meter powders, particle size was from 30nm to 80nm, but dispersing and repetition was not good. The optimal technology condition was that the consistency of Zn(NO3)2 was 1.50mol/l and mixed with 0.6wt% anion type surfactant, the consistency of Na2CO3 was 1.0mol/1, and Na2CO3 /Zn(NO3)2 mole ratio was about 1.75, stirring by electro-motion, after reacting for about 1h in constant temperature, take the mixture into alkalescence washing liquid whose PH value is 10.8 and wash several times, after that, washed by ethanol. Then filtrate the suspending liquid, gain precursor and dry them at 80℃. The precuesor are decompounded at 320℃ for 1h.After studying on ZnO nano-meter powders prepared by solid state reaction and direct precipitation method by TEM, FT-IR, XRD, UV/VIS spectrum, particle size analysis, ratio surface area analysis, absorbing light, dispersing analysis, it gained ZnO nano-meter powders prepare更多还原