【作者】 李红霞；

【导师】 龚剑；

【作者基本信息】 东北师范大学 ， 无机化学， 2010， 硕士

【摘要】 近年来,纳米材料的新颖结构引起了人们广泛的兴趣,本文旨在利用低温水热方法,设计不同的液相反应路线,合成出多种形貌的Fe2O3和ZnO纳米结构。利用各种分析手段,对产物进行表征和分析,并结合晶体生长的各种因素,对氧化物的生长取向和机理进行了初步的探讨。论文的主要内容归纳如下:1.利用低温水热合成方法,在表面活性剂PEG-400的协助下,成功合成出不同形貌的三氧化二铁纳米晶体,并对产物进行了各种表征。通过改变表面活性剂的量,六亚甲基四胺的量以及反应温度等实验条件,控制合成出各种形貌的三氧化二铁纳米晶体,并根据实验结果讨论了以上反应条件影响产物形貌的原因,最后提出了晶体生长的可能机理。2.利用水热体系,以二氧化硅纳米粒子为模板,简单,有效地合成出空心α-Fe2O3纳米球。用各种测试手段,对产品进行了表征,结果表明所得空心球分散性较好,尺寸在300-350 nm之间,外壳厚度大约为50 nm,中空部分与二氧化硅的尺寸一致。最后提出了空心球的可能形成机理。3.在低温水热体系中,利用三乙醇胺作为配位剂,尿素为分散剂合成出不同的氧化锌纳米球,并用各种手段对产物进行表征。三乙醇胺在体系中作为配位剂,对晶体的生长起着一定的导向作用,而尿素能够影响纳米球表面的组成。研究了反应时间,反应物的量,温度等条件对产物形貌的影响。并测定了产物的荧光性质,提出了可能的生长机理。更多还原

【Abstract】 In recent years, nanomaterials with novel nanostructures have attracted significant attention. In this paper ,we used hydrothermal method under low temperature, designed many different solution chemical route, and synthesized Fe2O3 and ZnO nanomaterials with different morphologies. The metal oxide have been characterized and analyzed. And in base of the crystal grow condition, the crystal grow orientation and crystal grow mechanisms of the metal oxide have been discussed. The main work of this paper as following:1.By a low-temperature hydrothermal method, different morphological Fe2O3 nanocrystals have been successfully fabricated under the surfactant assistance. The samples were characterized by field emission scanning electron microscopy, energy-dispersive x-ray spectroscopy. Fe2O3 various nanostructures morphologies have been obtained by changing the conditions of the system. The reasons which affect nanostructures have been analyzed ,and finally a possible crystal grow mechanisms have been discussed.2. In the hydrothermal system,α-Fe2O3 hollow nanospheres were successfully prepared by using SiO2 nanospheres as templates. This is a simple, effective method for fabricating hollow-spheres. The hollow nano-spheres were characterized by IR spectrum, X-raydiffraction (XRD) analysis, (SEM) images, transmission electronmicroscope (TEM) and EDAX. The hollow nanospheres were disperse, the size of the hollow nanospheres ranges from 300 to 350 nm, and the shell thickness is sbout 50 nm. The inner diameters ofα-Fe2O3 hollow nanospheres were similar to the diameter of the silica microspheres. Finally , a possible crystal grow mechanisms have been discussed.3. Large-scale ZnO nanospheres were successfully synthesized via a low-temperature hydrothermal process. In this process, TEA was the ligands and CO(NH)2 was the dispersant. The samples were characterized by SEM images, XRD analysis, IR, EDAX. The results revealed that TEA played a crucial role in determining the shape of the samples. And the existence of CO(NH)2 was important to the surface of nanospheres. The affect of the react-time, temperature for the nanostures have been researched. We also investigated optical properties of the samples by PL spectroscopy. At last, we proposed a possible formation mechanism.更多还原