制备ZIF-8PAN复合材料及其气体吸附性能的研究

摘要

摘要

本文以甲醇为溶剂使用溶剂热法合成ZIF-8晶体,接着将晶体分散在PAN/DMF溶液中，然后用静电纺丝的方法制备出一系列ZIF-8/PAN复合纤维膜。对所制得的复合纤维膜进行N2吸附实验、扫描电镜（SEM）和热重（TG）的表征分析以及CO2吸附性能研究。从N2吸附曲线来看，相对于纯PAN纤维膜，ZIF-8/PAN复合纤维膜的比表面积具有很大的提高，ZIF-8负载量的增加有利于增强复合材料的孔性能。通过对SEM图进行比较，发现随着ZIF-8晶体负载量的增加，复合膜纤维表面的串珠结构也随之增加，分布也更加均匀,也即复合纤维膜表面的ZIF-8晶体随着ZIF-8负载量的增加而逐渐增加。通过对热重（TG）曲线进行分析并分别计算复合纤维膜中ZIF-8和PAN的实际含量，发现复合材料中ZIF-8的实际含量大于理论值。CO2吸附曲线结果表明了ZIF-8/PAN复合纤维膜对于CO2的吸附性能与其比表面积的趋势一致，即随着ZIF-8含量的提高，复合材料对CO2的吸附量就越高，这预示着若能优化复合纤维膜中ZIF-8的负载量，所得的复合纤维膜将会在CO2吸附应用上有很好的发展前景。

作为比较，本文还通过了原位生长法制备ZIF-8/PAN复合纤维膜并作了简单的比较。

关键词：ZIF-8，PAN，复合材料，气体吸附性能，静电纺丝，原位生长

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Abstract

Abstract

In this paper, ZIF-8 crystals were synthesized by using methanol as solvent via solvent-thermal method, and in the next step a certain amount of the obtained crystals were dispersed in PAN/DMF solution, after that a series of ZIF-8/PAN composite fiber membranes were prepared through electrostatic spinning method.

The N2 ads-desorption experiment, thermogravimetric analysis (TG), scanning electron microscopy (SEM) and CO2 adsorption tests were conducted on these prepared composite fiber membranes. From the N2 ads-desorption curves, the specific surface area of composite fiber membranes is larger than pure that of pure PAN fiber membrane, and the increasing loading of ZIF-8 crystals is benefit to enhance the pore properties of composite fiber membranes. By comparing the SEM images, the beaded structures on the surface of composite fiber membranes increased and distributed more evenly, which means the number of ZIF-8 crystals on the surface of composite membranes increased gradually with the loading of ZIF-8 increasing. By analyzing the thermo-gravimetric (TG) curve and calculating the actual content of ZIF-8 and PAN in the composite fiber membranes，respectively，we found that the actual content of ZIF-8 in the composite was larger than the theoretical value. The CO2 adsorption curves showed that the CO2 adsorption properties of ZIF-8/PAN composite fiber membranes are in perfect accordance with their specific surface area trend, which means composite fiber membranes have higher CO2 adsorption capacities with the increase of ZIF-8 contents. It indicates that if the loading of ZIF-8 can be optimized, the obtained composite fiber membranes would have great potential in the application of CO2 adsorption.

ZIF-8/PAN composite membrane was synthesized by in-situ growth method and simply characterized for comparison purpose.

Key words: ZIF-8, PAN, composite, gas adsorption properties, electrostatic spinning, in-situ growth

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目 录

目录

摘要 ................................................................................................................................................................. I Abstract ........................................................................................................................................................... II 目录 ..................................................................................................................................................................i 第一章 绪论 ................................................................................................................................................... 1

1.1 金属-有机骨架材料的简介 ........................................................................................................... 1

1.1.1 ZIFs系列材料的简介 ........................................................................................................ 2 1.1.2 ZIF-8材料的简介 .............................................................................................................. 2 1.1.3 MOFs复合材料的研究 ........................................................................................................ 4 1.2 聚丙烯腈（PAN）材料的简介 ....................................................................................................... 4 1.3 ZIF-8纳米复合材料的研究 .......................................................................................................... 5 1.4 静电纺丝 ......................................................................................................................................... 5

1.4.1 静电纺丝的影响因素 ......................................................................................................... 6 1.5 课题的提出 ..................................................................................................................................... 7 第二章 实验部分 ........................................................................................................................................... 8

2.1 原料与仪器 ..................................................................................................................................... 8

2.1.1 原料 ..................................................................................................................................... 8 2.1.2仪器设备 .............................................................................................................................. 8 2.2 ZIF-8的制备 .................................................................................................................................. 9 2.3 原位生长法制备ZIF-8/PAN复合材料 ....................................................................................... 10

2.3.1 静电纺丝法制备PAN膜 ................................................................................................... 10 2.3.2 原位生长法制备ZIF-8/PAN复合纤维膜 ....................................................................... 12 2.4 静电纺丝法混纺ZIF-8/PAN复合纤维膜 ................................................................................... 12

2.4.1 合成ZIF-8 ........................................................................................................................ 12 2.4.2 配制10%的PAN/DMF溶液 ................................................................................................ 12 2.4.3 配制10%的PAN/ZIF-8混合溶液 .................................................................................... 13 2.4.4 混合液的静电纺丝 ........................................................................................................... 13 2.5 10%PAN/ZIF-8复合纤维膜的表征 .............................................................................................. 14

2.5.1 N2吸附实验 ....................................................................................................................... 14 2.5.2 SEM表征 ............................................................................................................................ 14 2.5.3 热重分析法（TG）表征 ................................................................................................... 14 2.5.4 CO2吸附实验 ..................................................................................................................... 14

第三章 结果与讨论 ..................................................................................................................................... 15

3.1 N2吸附实验结果 ........................................................................................................................... 15

3.1.1 纯PAN纤维薄膜的N2吸附曲线 ...................................................................................... 15 3.3.2 ZIF-8/PAN复合纤维薄膜的N2吸附曲线 ....................................................................... 16 3.2 纯PAN纤维膜的形貌（SEM图） ................................................................................................ 17 3.3 ZIF-8/PAN复合纤维薄膜的形貌（SEM图） ............................................................................. 19 3.4 热重分析 ....................................................................................................................................... 19 3.5 复合材料的CO2吸附 .................................................................................................................... 21 第四章 结论与展望 ..................................................................................................................................... 23

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广东石油化工学院毕业论文：制备ZIF-8/PAN复合材料及其气体吸附性能的研究

4.1 总结 ............................................................................................................................................... 23 4.2 展望 ............................................................................................................................................... 23 致谢 .............................................................................................................................................................. 25 参考文献....................................................................................................................................................... 26

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