| 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...
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