纳米二氧化硅材料的绿色合成 - 图文

北京化工大学毕业设计（论文）

纳米二氧化硅材料的绿色合成

摘 要

纳米二氧化硅作为一种新型材料，在塑料、半导体材料、橡胶工业、光电材料和土木工程中占据越来越重要的地位。本文研究了在离子液体中利用溶胶-凝胶法制备纳米二氧化硅，考察了实验条件对二氧化硅颗粒形貌和大小的影响，得到了一系列有价值的实验结果。

本文讨论了乙醇对于二氧化硅制备的影响。考察了加乙醇与无乙醇两种情况下的二氧化硅形貌与分散性，实验结果表明加入乙醇的样品粒径小于无乙醇的样品，而且分散性较之更好。其次，探讨了酸碱度的不同对于样品形态与分散性的影响。

实验研究了两种不同的离子液体1-丁基-3-甲基咪唑六氟磷酸盐离子液体([C4mim]PF6)与1-十六碳基-3-甲基咪唑氯盐离子液体([C16mim]Cl)作为反应介质对二氧化硅形貌与分散性的影响，并通过透射电子电镜(TEM)对样品进行了分析，结果表明采用 1-十六碳基-3-甲基咪唑氯盐离子液体分散效果较佳。

最后，本文还研究了加料顺序对样品形貌与分散性的影响，得到了一种特殊形貌的二氧化硅微粒。结果表明，不同的实验条件对于二氧化硅的形貌有着重要的影响。

关键词：纳米二氧化硅，离子液体， 溶胶-凝胶法， 绿色合成

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北京化工大学毕业设计（论文）

The Green Synthesis of the Nano-sized Silica Materials

ABSTRACT

As a new type of material, nano-sized silica is taking more and more important place in plastic, semiconductor materials, rubber industry, photoelectricity materials and construction projects. In this article, we investigated that different experimental conditions influenced on the morphologies and particle size of the silica in the preparation with sol-gel method and obtained a series of valuable results.

In this paper, the effects of ethanol in the synthesis were discussed. It was found that the particle size of the sample prepared with ethanol was smaller than that without ethanol, and the dispersibility of the sample also was better than the latter system. In addition, we studied the influence of pH value on the sample’s shape and dispersibility. Two

different

types

of

ionic

liquid

including

1-Butyl-3-methylimidazolium hexafluorophosphate ionic liquid ([C4mim]PF6) and 1-Hexadecyl-3-methylimidazolium chloride([C16mim]Cl) were used as synthetical media and their effects on both morphologies and dispersibility of samples were elucidated by TEM. The results showed that 1-Hexadecyl-3-methylimidazolium chloride is better.

Finally, we also investigated the effect of sequence of adding materials on the shape and dispersibility. A special shape of silica particles was obtained in the experiment. The results indicated that different experimental conditions have a great effect on the shape of silica.

Key words: nano-sized silica, ionic liquid, sol-gel processes, green synthesis

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北京化工大学毕业设计（论文）

目 录

摘 要........................................................................................................Ⅰ ABSTRACT...............................................................................................Ⅱ 前 言........................................................................................................ 1 第一章 文献综述.................................................................................... 2 第1.1节 离子离子液体概述................................................................... 2 1.1.1 离子液体的历史与发展............................................................ 2 1.1.2 室温离子液体的概念................................................................ 2 1.1.3 离子液体的性质........................................................................ 3 1.1.4 离子液体的种类与特点............................................................ 4 1.1.5 离子液体的应用前景................................................................ 5 第1.2节 溶胶-凝胶法概述...................................................................... 5 1.2.1 溶胶-凝胶法概况....................................................................... 5 1.2.2 溶胶-凝胶法原理及过程........................................................... 5 第1.3节 二氧化硅颗粒制备及形成过程研究....................................... 7 第1.4节 本课题研究目的和意义及方法............................................... 8 1.4.1 论文选题的立论、目的和意义................................................ 8 1.4.2 本课题研究方法........................................................................ 9 第二章 实验部分.................................................................................. 10 第2.1节 溶胶-凝胶法生成二氧化硅的反应机理.............................. 10 第2.2节 实验设计............................................................................... 10 第2.3节 实验内容............................................................................... 11 2.3.1 试剂及仪器设备.................................................................... 11 2.3.2 实验过程................................................................................ 12 2.3.3 表征手段................................................................................ 13 第三章 结果与讨论.............................................................................. 14

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北京化工大学毕业设计（论文）

第3.1节 二氧化硅—离子液复合物结构表征................................... 14 3.1.1 透射电子显微镜照片............................................................ 14 3.1.2 傅立叶变换红外分析............................................................ 14

3.1.3 热失重分析 .......................................................................... 16

3.1.4 X-射线粉末衍射分析............................................................ 17 第3.2节 温度对反应的影响............................................................... 17 第3.3节 乙醇与水对二氧化硅形貌的影响....................................... 18

3.3.1 乙醇影响的考察.................................................................. 18

3.3.2 水量影响的考察.................................................................. 18 第3.4节 pH值对二氧化硅形貌的影响............................................. 20 第3.5节 加料顺序对二氧化硅形貌的影响....................................... 21 第3.6节 不同离子液作为反应介质的影响....................................... 22 3.6.1 二氧化硅的透射电镜照片.................................................. 22 3.6.2 调整pH值的二氧化硅透射电镜照片............................... 23 3.6.3 加乙醇后 二氧化硅的透射电镜照片................................ 23 第四章 结论........................................................................................ 25 第五章 问题与展望............................................................................ 26 第5.1节 实验的问题........................................................................... 26 第5.2节 考虑与展望........................................................................... 26 参考文献.................................................................................................. 27 致谢 ........................................................................................................ 29

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