基于离子自组装构建的超分子纳米材料及其功能

发布时间：2018-05-19 23:26

本文选题：超分子 + 离子自组装　；参考：《山东大学》2016年硕士论文

【摘要】：超分子化学带动了纳米材料、有机凝胶、有机-无机杂化材料和生物分子材料等新材料的发展。超分子自组装策略被广泛应用于制备各种功能性材料。作为超分子自组装方法之一,离子自组装(ISA)为将简单的构筑单元组装成规则的(well-defined)、离散的(discrete)超分子结构提供了一条有效且通用的路线。这种基于静电作用的策略由于具有普适性、简单和便宜等优点而引起了研究者的关注。在本文中,我们合成了多种表面活性离子液体,并选择合适的带相反电荷的分子,应用离子自组装策略制备了超分子材料。论文的内容主要分为以下四个部分：第一章介绍了与本论文密切相关的基础知识以及近几年国内外在采用离子自组装策略制备超分子纳米材料领域的研究进展,并提出了本论文的立题依据和研究思路。第二章采用表面活性剂与有机小分子进行离子自组装制备了超分子纳米材料。(1)基于离子自组装策略,使用羧基功能化表面活性离子液体—N-癸基-N’-羧甲基咪唑溴([N-C10, N'-COOH-Im]Br)与刚果红(CR)染料分子构建了有强荧光性质且同时具有pH和温度双重响应的超分子材料。发现CR/[N-C10,N'-COOH-Im]Br (摩尔比为1：2)体系在pH为3.2的水溶液中组装成1D的细长纤维。值得注意的是当pH继续增大至9.0时,1D纤维逐渐变成2D平面结构(如竹叶状结构、梭形、圆盘状和矩形状结构)。尤为有趣的是,形成的1D和2D超分子材料之间的相互转变是可逆的。同时,我们也发现随着温度的升高,纳米纤维会逐渐聚集成纤维束。此外,当pH在3.2和9.0之间变化时,制备的1D和2D超分子材料具有荧光开关的性质。静电作用、疏水作用和π-π堆积被证明是形成CR/[N-C10, N'-COOH-Im]Br超分子材料的主要驱动力,Gauss优化结果表明刚果红分子的二聚体之间的π-π堆积也起着重要的作用。(2)利用成本较低廉的商用表面活性剂—二(2-乙基己基)磺基琥珀酸酯钠(NaAOT)与染料分子罗丹明6G通过离子自组装制备了长度达到2厘米的纤维。这种纤维展现了很好的机械强度和良好的柔韧性,同时具有强荧光性质和有机半导体性质。在超分子材料的形成过程中出现了一个非常罕见的现象,纳米颗粒首先链状生长,然后再折叠聚集成宏观纤维。在此基础上探究了宏观纤维的形成机理。(3)基于超分子自组装策略,偶氮苯羧酸在pH=3.2的水溶液中能够自组装形成纳米棒,当pH升高到6.5时,形成多边形材料；在紫外光照下纳米棒完全消失,形成纳米球。仅通过改变基于偶氮苯羧酸分子与模板分子(β-环糊精；[N-C, N'-COOH-Im]Br,n=10,12,14；CTAB)之间的弱相互作用,在表面活性剂的辅助作用下能够调控形成鼠尾草(salvia officinalis)状纤维、细长纤维,纳米颗粒和球状颗粒的聚集体等形状的超分子材料。其中,将[N-C10, N'-COOH-Im]Br水溶液加入到β-CD/偶氮羧酸钠复合物体系中,得到的鼠尾草(salvia officinalis)状材料极其罕见。循环伏安实验和密度泛函理论(DFT)优化计算表明,这种材料具有优良的光电性能,在形成光电器件方面具有潜在的应用价值。第三章通过表面活性离子液体与多金属氧化簇(POM)进行离子自组装构筑了超分子纳米材料,并研究了其在催化和生物方面的应用。(1)通过离子自组装策略,在水溶液中将带有相反电荷的表面活性离子液体([N-C10, N'-COOH-Im]Br)包覆在K eggin型多金属氧化簇(磷钨酸)的表面,形成了具有pH响应、有良好的电化学性质和催化性质的有机-无机杂化材料。这种基于POM的杂化材料在降解染料分子方面表现出了良好的催化活性。尤其有趣的是由于表面活性离子液体与多金属氧化簇之间存在着静电作用,pH的变化能够驱动杂化材料的解组装与再组装,同时能够使得杂化材料的催化活性重新恢复。更有意义的是相比于传统的催化剂,这种新型POM/[N-C10, N'-COOH-Im]Br催化剂即使在黑暗的条件下也能催化反应,同时这种具有pH响应的催化剂能够解决异相催化剂中普遍存在的催化剂中毒问题。(2)在水溶液中,通过离子自组装制备了表面活性离子液体([N-C12, N'-COOH-Im]Br)/稀土包覆的多金属氧化簇Na9EuWio036-32H20 (Eu-POM)超分子纳米球。发现这些单分散性的超分子球具有pH调控的可逆自组装性质和优良的光致发光性质。有趣的是,制备的[N-C12,N'-COOH-Im]Br/Eu-POM超分子纳米球导致了Eu-POM 荧光性质的猝灭,这种猝灭机制是因为Eu-POM与表面活性离子液体之间存在的氢键阻断了POM中d1电子的跃迁。然而,随着pH的升高,[N-C12, N'-COOH-Im]Br去质子化,形成的超分子纳米球解组装,使得材料的荧光光学性质完全恢复。基于pH驱动超分子球的解组装与再组装以及具有浊度和荧光性质的双重检测信号特征,我们将其应用于生物分子脲酶和重金属离子的检测中。此外,甲基橙(MO)作为客体分子很容易被包覆到超分子球中,通过外界环境的刺激响应去控制超分子球的解组装,能够使得被包覆在其中的客体分子被释放出来。这表明刺激响应型的Eu-POM/[N-C12, N'-COOH-Im]Br超分子材料在药物缓释方面也具有潜在的应用价值。(3)在水溶液中,制备了具有超长荧光寿命(3.758 ms)和高量子产率(25.17%)的稀土包覆的多金属氧化簇(Eu-POM)/Gemini型表面活性剂(1,2-双(十六烷基咪唑)-溴乙烷,[C16-2-C16im]Br2)杂化球。发现这种杂化材料具有良好的生物相容性,能够在生物细胞中作为生物探针应用于生物成像。第四章将多金属氧化簇(POM)和十六烷基三甲基溴化铵(CTAB)通过离子自组装制备了具有两亲性质的超分子复合物。然后利用两亲性超分子复合物和温度敏感型离子液体——三氟乙酸四丁基鳞([P4444][CF3COO])构建了一个新型的催化体系。[P4444][CF3COO]在25℃时能够在水中形成类微乳液,两亲性超分子复合物能够溶解到类微乳液的液滴中。当温度升高至35℃时,离子液体和水发生相分离,超分子复合物会随着离子液体与水的分离而留在离子液体相中。我们将这种温度驱动的异相分离体系应用到了催化方面。在25℃下经紫外光照(365 nm)照射30 min后,发现POM/CTAB超分子复合物能够催化重铬酸钾,将Cr(Ⅵ)变成Cr(Ⅲ)。当升温至35℃时,溶有超分子复合物的离子液体相与Cr(III)水溶液发生相分离。POM/CTAB-[P4444][CF3COO]催化体系在经多次循环使用之后仍保持良好的催化活性。因此这种新型催化体系在克服异相催化剂的中毒现象方面具有良好的应用前景。
[Abstract]:Supramolecular chemistry has led to the development of nanomaterials, organogels, organic-inorganic hybrid materials and biomaterials. Supramolecular self-assembly strategies are widely used in the preparation of various functional materials. As one of the supermolecule self-assembly methods, ISA (well-def) is used as a rule to assemble simple construction units (well-def Ined), the discrete (discrete) supramolecular structure provides an effective and universal route. The strategy based on the electrostatic action has attracted the attention of researchers because of its universality, simplicity and simplicity. In this paper, we synthesized a variety of surface active ionic liquids and selected appropriate molecules with opposite charges. The supramolecular materials are prepared by the ion self-assembly strategy. The main contents of this paper are divided into four parts: the first chapter introduces the basic knowledge which is closely related to this paper and the research progress in the field of using the ion self-assembly strategy to prepare the supramolecular nanomaterials at home and abroad in recent years, and puts forward the basis and research of this paper. The second chapter uses the surface active agent and the organic small molecules to prepare the supramolecular nanomaterials. (1) based on the ion self-assembly strategy, the carboxyl functionalized surface active ionic liquids - N- decyl -N '- carboxymethyl imidazolium bromide ([N-C10, N'-COOH-Im]Br) and the Congo red (CR) dyes - have been constructed with strong fluorescence properties and CR/[N-C10, N'-COOH-Im]Br (mole ratio is 1:2) system is assembled into slender fibers of 1D in pH 3.2 water solution. It is worth noting that when pH continues to increase to 9, 1D fiber gradually becomes a 2D plane structure (such as bamboo, shuttle, disc and rectangle). It is particularly interesting that the transformation between the 1D and 2D supramolecular materials is reversible. At the same time, we also find that as the temperature increases, the nanofibers will gradually integrate into the fiber bundles. In addition, when pH changes between 3.2 and 9, the prepared 1D and 2D supramolecular materials have the properties of the fluorescent switches. Electrostatic action, hydrophobicity and PI. The pion accumulation is proved to be the main driving force for forming CR/[N-C10, N'-COOH-Im]Br supramolecular materials. Gauss optimization results show that the pion pion accumulation between the two polymers of the Congo red molecules also plays an important role. (2) use of the cheaper commercial surface active agent - two (2- ethyl hexyl) sulfonylsuccinate sodium (NaAOT) and dye molecule Luo Dan 6G was prepared by ion self-assembly to produce a fiber with a length of 2 centimeters. The fibers exhibit good mechanical strength and good flexibility, with strong fluorescence and organic semiconductors. A very rare phenomenon occurs during the formation of supramolecular materials. The nanocrystalline particles are first linked and then refolded. On the basis of this, the formation mechanism of macro fiber is explored. (3) based on the supramolecular self-assembly strategy, azobenzene carboxylic acid can form a nanorod in the aqueous solution of pH=3.2 and form a polygon material when the pH rises to 6.5; the nanospheres are completely disappeared under ultraviolet light. The weak interaction between azobenzene carboxylic acid molecules and template molecules (beta cyclodextrin; [N-C, N'-COOH-Im]Br, n=10,12,14; CTAB) can be used to regulate the formation of sage (Salvia officinalis) like fibers, slender fibers, nanoparticles and spherical particles in the form of supermolecular materials. [N-C10, N'-COOH-Im]Br aqueous solution is added to the sodium azo carboxylate complex system of beta -CD/. The obtained sage (Salvia officinalis) like material is extremely rare. Cyclic voltammetry and density functional theory (DFT) optimization results show that this material has excellent photoelectric energy and has potential application value in the formation of optoelectronic devices. In the third chapter, the supramolecular nanomaterials are constructed by self assembly of surface active ionic liquids and polymetallic oxide clusters (POM), and their applications in catalytic and biological aspects are studied. (1) the surface active ionic liquids ([N-C10, N'-COOH-Im]Br) with opposite charges (N'-COOH-Im]Br) are coated in K egg in aqueous solution by the ion self assembly strategy. The surface of in type polymetallic oxide cluster (phosphotungstic acid) has formed an organic inorganic hybrid material with pH response, good electrochemical properties and catalytic properties. This hybrid material based on POM shows good catalytic activity in the degradation of dye molecules. It is especially interesting that the surface active ionic liquid and polymetallic oxide cluster are the most interesting. There is an electrostatic interaction between them. The change of pH can drive the disassembly and reassembly of the hybrid materials, and the catalytic activity of the hybrid materials can be restored. It is more significant that the new type of POM/[N-C10, the N'-COOH-Im]Br catalyst, can catalyze the reaction even in the dark conditions. The catalysts with pH response can solve the ubiquitous catalyst poisoning problems in heterogeneous catalysts. (2) in aqueous solution, surface active ionic liquids ([N-C12, N'-COOH-Im]Br) / Rare Earth Coated polymetallic oxide cluster Na9EuWio036-32H20 (Eu-POM) supermolecule nanospheres are prepared by self assembly in aqueous solution. The subspheres have pH controlled reversible self assembly properties and excellent photoluminescence properties. Interestingly, the prepared [N-C12, N'-COOH-Im]Br/Eu-POM supramolecular nanospheres cause the quenching of Eu-POM fluorescence properties. This quenching mechanism is because the hydrogen bonds between Eu-POM and surface active ionic liquids block the transition of D1 electrons in POM. With the increase of pH, [N-C12 and N'-COOH-Im]Br are protonated and formed by supermolecular nanospheres, which make the fluorescence optical properties of the material completely restored. Based on the dual detection signal characteristics of the pH driven supramolecular spheres and the turbidity and fluorescence properties, we apply it to the urease and heavy gold of the biomolecules. In addition, the methyl orange (MO) is easily encapsulated into a supramolecular sphere as an guest molecule. It can be controlled by the response of the external environment to control the assembly of the supramolecular sphere. It can be released by the guest molecules coated in it. This indicates that the Eu-POM/[N-C12, N'-COOH-Im]Br supramolecular material that stimulates the response to the response type is in the form of supramolecular molecules. Drug release also has potential application value. (3) in aqueous solution, a rare earth coated polymetallic oxide cluster (Eu-POM) /Gemini surfactant (1,2- double (sixteen alkyl imidazole) bromo ethane, [C16-2-C16im]Br2) hybrid spheres with a long fluorescence lifetime (3.758 MS) and a high quantum yield (25.17%) was prepared. In the fourth chapter, polymetallic oxide clusters (POM) and sixteen alkyl three methyl ammonium bromide (CTAB) are prepared by self assembly of polymetallic oxide clusters (POM) and sixteen alkyl groups, and then use two amphiphilic supramolecular complexes and thermosensitive ions. Liquid - three FLUOROACETIC acid four butyl scale ([P4444][CF3COO]) constructed a new catalytic system,.[P4444][CF3COO], to form a microemulsion in water at 25 C. Two Pro supramolecular complexes can be dissolved in a droplet of a microemulsion. When the temperature rises to 35, the separation of the liquid from the water and the supramolecular complex can be found. With the separation of the ionic liquid and water in the ionic liquid phase, we applied the temperature driven heterogenous separation system to the catalytic aspect. After irradiation of 30 min by ultraviolet light (365 nm) at 25 C, it was found that the POM/CTA B supermolecule complex could catalyze potassium dichromate and transform Cr (VI) into Cr (III). The ionic liquid phase of the subcomplex and the Cr (III) aqueous solution phase separation.POM/CTAB-[P4444][CF3COO] catalytic system still maintains good catalytic activity after repeated use. Therefore, this new catalytic system has a good application prospect in overcoming the toxic phenomenon of heterogeneous catalyst.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O641.3;TB383.1

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