论文总字数：21415字

摘 要

介孔二氧化硅分子筛MCM-41，具有有序的六方孔道结构、易于修饰的孔表面，普遍用于吸附分离、催化和环境治理等范畴。另外，介孔分子筛合成方式多样，主要有溶胶-凝胶法、水热合成法，室温合成法、微波合成法、相转变法等。本论文概述了介孔二氧化硅分子筛MCM-41的特性、合成方式以及有机功能化的方式及应用前景。

偶氮苯及其衍生物的光致异构特性，使得它在光照刺激下可由顺式构型向反式构型转变，同时发生空间尺寸及分子极性的改变，是一种可逆的光响应分子。本课题通过将偶氮本衍生物引入介孔二氧化硅MCM-41，制备具有光控分子开关的智能吸附剂。在紫外光照下，分子开关打开，偶氮苯衍生物构型由反式转变为顺式，导致MCM-41孔道内表面的活性位点被偶氮苯分子链遮蔽。在此情况下，只有尺寸较小的吸附质分子才能进入分子开关与活性位之间的狭小空间，两者发生分子间相互作用，而尺寸较大的吸附质则无法接触活性位，从而实现选择性吸附。此后，经可见光光照关闭分子开关，将活性位暴露，通过解吸剂将吸附质洗脱，从而实现高效再生。

关键词：MCM-41 偶氮苯 光响应 选择性 吸附分离

The preparation of Azobenzene functionalized adsorbent in response to light and performance exploration

Abstract

MCM-41, having an ordered hexagonal pore structure, and ease of modification of the surface hole, widely used in adsorption, catalysis, separation and other fields, and the mesoporous molecular sieve synthesis methods varied, mainly the sol-gel method, hydro-thermal synthesis method, temperature synthesis, microwave synthesis, phase transformation method. This paper first discusses the significance of azobenzene and mesoporous molecular sieves study outlines the characteristics of MCM-41 mesoporous molecular sieves, organic synthesis and functional.

The photo-isomerization of azobenzene molecule from trans to cis configuration, responsive to external light exposure, is reversible. Here, smart adsorbents equipped with photo-regulated molecular switches are successfully fabricated by introducing of AB derivative to the mesoporous silica MCM-41. By photo-stimulated isomerization of azobenzene units, the molecular switches are reversibly on/off according to UV/visible light stimuli. When the molecular switches are turned on by UV light, the formation of trans-cis isomerization makes the active sites on the internal pore surface of MCM-41 obstructed by cis configuration molecular chains. On this occasion, the bonding sites are only accessible to small molecules, because they can enter the relatively small space between the bonding sites and molecular switches, which makes selective adsorption achieved. After the molecular switches are reversibly turned off by visible light, the bonding sites are exposed to let go adsorbed molecules freely with desorption solvent, thus realizing efficient regeneration. Accordingly, the smart adsorbent exhibits the ability of both selective adsorption and efficient desorption with photo-regulated molecular switches, which is highly expected for adsorptive separation but impossible to realize by traditional adsorbents with fixed pore surface properties. Our conception breaks the tradition that adsorbents always possess fixed pore surface properties, leading a promising direction in exploiting a new generation of adsorbents with a smart characteristic. The present strategy may open a new path for the development of smart adsorbents by using diverse stimuli-responsive groups (e.g. thermo, magnet, and pH) as molecular switches to realize adsorptive separation processes with high efficiency and low energy consumption

Key Words：MCM-41; Azobenzene; light responsive; selectivity; adsorptive separation;

目 录

摘 要 I

Abstract II

第一章 绪论 1

1.1 引言 1

1.2 介孔分子筛MCM-41 1

1.2.1 MCM-41分子筛的特征 1

1.2.2 MCM-41介孔分子筛的合成方法 2

1.3 介孔分子筛MCM-41的有机功能化 2

1.3.1 嫁接法 2

1.3.2共缩聚法 3

1.3.3 “组合”合成法 3

1.4 偶氮苯的光响应性 4

第二章 实验仪器及实验方法 5

2.1 实验仪器和材料 5

2.2 吸附剂的制备 6

2.2.1 光响应分子 6

2.2.2 光响应吸附剂 6

2.3 样品的表征 6

2.3.1 X射线衍射 6

2.3.2 比表面积和孔结构 7

2.3.3 傅里叶变换红外光谱 7

2.3.4 核磁共振 7

2.3.5 热重 7

2.3.6 元素分析 7

2.3.7 紫外-可见漫反射光谱 8

2.4 吸附性能测试 8

2.4.1 不同分子尺寸的染料溶液的配制 8

2.4.2 染料的标准曲线 8

2.4.3 吸附实验 8

2.4.4 脱附实验 9

第三章 负载AB-TPI的光响应吸附剂的制备及性能研究 10

3.1 引言 10

3.2 结果与讨论 10

3.2.1 光响应分子AB-TPI的表征 10

3.2.2 光响应吸附剂的表征 12

3.2.3 吸附性能研究 19

3.3 本章小结 22

第四章 结论与展望 24

4.1 结论 24

4.2 展望 24

参考文献 25

致谢 27

第一章 绪论

1.1 引言

在紫外或可见光照射下，偶氮苯及其衍生物具有光致异构化性。它的这种性质可导致化合物在光作用下发生多种其他性能的改变，利用这一特点，这类物质可作光开关，光信息存储，蛋白质折叠，人工分子马达，和其他微机械光学特性的物质。芳香族含氮化合物偶氮苯，其晶体为橙红色片状，能溶于醇、醚、苯、冰醋酸等有机溶剂，不溶于水。它的用途与它含氮氮双键的结构有关联，染料和分析试剂这方面用的较多。偶氮聚合物在光信息存储材料、非线性光学材料、液晶材料、纳米材料等领域有着广泛应用。

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