配位聚合物二维纳米晶的可控合成及性质

发布时间：2018-05-30 06:51

本文选题：纳米片 + 阴离子表面活性剂　；参考：《南京邮电大学》2017年硕士论文

【摘要】：配位聚合物二维纳米材料具有高比表面积、易于成膜、表面化学可修饰等优势,使其成为当前化学和材料学家关注的焦点。本课题围绕卟啉配体、C_2、C_3对称性苯羧酸类配体,提出阴离子表面活性剂辅助策略,并成功实现了一系列不同种类配位聚合物二维纳米结构的可控合成,主要研究工作如下:1.以5,10,15,20-四(4-吡啶基)卟啉和5,10,15,20-四(4-羧基苯基)卟啉为基本构筑单元,通过阴离子表面活性剂辅助配位组装法合成了多种单分散金属卟啉纳米片,并系统研究了表面活性剂种类、反应时间和温度对纳米片合成的影响,对纳米片形貌、聚集态结构进行了系统表征,结果表明该策略成功制备了分散性、稳定性良好、尺寸均匀的M-TPyP/TCPP纳米片。通过纳米片的XRD、吸收光谱及TG数据分析,我们猜测当金属卟啉某一晶面的金属离子浓度最高,SDS会通过静电作用优先吸附于该晶面,通过封端作用限制该晶面生长速率,诱导晶体发生各向异性生长,进而抑制晶体三维方向中某一维度的生长,生成2D片状结构。2.以上述卟啉体系为研究对象,选用带不同电荷的表面活性剂CTAB及PVP,相同的实验条件下,SEM测试结果表明CTAB和PVP条件下金属卟啉晶体更倾向于生成零维、三维纳米结构,如Cu/Zn-TPyP多面体、CuTCPP花簇结构等,XRD图谱表明该条件下样品与SDS体系具有不同空间群和优势晶面,UVVis图谱中Cu/Zn-TPyP晶体Soret带吸收峰发生了蓝移,配体卟啉分子间发生了明显的H-聚集。而SDS条件下,Cu/Zn-TPyP纳米片样品吸收峰红移,均发生了典型的J-聚集。实验结果表明金属卟啉纳米晶发生了与SDS不同的生长过程,二者主要通过特定形状胶束辅助金属卟啉完成组装过程,从而实现对金属卟啉纳米晶的可控制备。3.实现了基于1,4-对苯二甲酸(H_2BDC)和1,3,5-均苯三甲酸(H_3BTC)配体的MOF-5及HKUST-1纳米片制备,并研究了SDS、CTAB及PVP对配位聚合物纳米结构形貌的影响。
[Abstract]:Coordination polymer two-dimensional nanomaterials have the advantages of high specific surface area, easy film formation and surface chemically modifiable, which make them become the focus of current chemistry and materials scientists. In this paper, a novel anionic surfactant assistant strategy was proposed around the porphyrin ligand C _ 2C _ 3 symmetric benzene carboxylic acid ligands, and a series of coordinated polymers were successfully synthesized. The main research work is as follows: 1: 1. Several mono-dispersed metalloporphyrin nanocrystals were synthesized by anionic surfactant assisted coordination assembly method, using 5 ~ (10) ~ 10 ~ (10) ~ 15 ~ (15) -tetra-4-pyridyl) porphyrin and 5 ~ (10) ~ 10 ~ (15) ~ 15 ~ (15) -tetra-4-carboxyphenyl) porphyrin as the basic building unit, and the types of surfactants were systematically studied. The effects of reaction time and temperature on the synthesis of M-TPyP/TCPP nanoparticles were investigated. The morphology and structure of the nanoparticles were systematically characterized. The results showed that the M-TPyP/TCPP nanoparticles with good dispersion, good stability and uniform size were successfully prepared by this strategy. Based on the analysis of the XRD, absorption spectra and TG data of the nanoparticles, we speculate that when the concentration of metal ions on a metalloporphyrin crystal plane is the highest, SDS will be preferentially adsorbed on the crystal surface by electrostatic action, and the growth rate of the crystal surface will be limited by the capping action. The anisotropic growth of crystals is induced, which inhibits the growth of one dimension in the three-dimensional direction of the crystal and generates 2D flake structure. 2. Taking the porphyrin system as the research object, the surface active agents CTAB and PVP with different charge were selected. The results showed that the metalloporphyrin crystals under the same experimental conditions were more inclined to form zero-dimensional and three-dimensional nanostructures under the same experimental conditions. For example, the structure of Cu/Zn-TPyP polyhedron CuTCPP clusters shows that there is blue shift in the absorption peak of Cu/Zn-TPyP crystal Soret band and obvious H- aggregation between the ligand porphyrin molecules in the Cu/Zn-TPyP crystal Soret band spectra under the condition that the sample and SDS system have different space groups and dominant crystal planes. On the other hand, the red shift of absorption peak of CuZn-TPyP nanocrystals under SDS condition is typical J-aggregation. The experimental results show that metalloporphyrin nanocrystals have a different growth process than SDS, and they mainly complete the assembly process of metalloporphyrins by special shape micelles, so as to realize the controllable preparation of metalloporphyrin nanocrystals. 3. The preparation of MOF-5 and HKUST-1 nanochips based on the ligands of 1h2BDCand 1h2BDCand 1h2BDCand H3BTC2BDC) were carried out, and the effects of PVP and DS-CTAB on the morphology of coordination polymer nanostructures were studied.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O634;TB383.1

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