刚性硝基—联苯羧酸和吡啶羧酸配体功能性配位聚合物的构筑及磁性、荧光性能研究

发布时间：2018-04-17 03:11

  本文选题：配位聚合物 + 镧系金属有机框架　； 参考：《西北大学》2017年硕士论文

【摘要】：金属-有机框架化合物(Metal-organic Frameworks,MOFs)作为配位聚合物(Coordination Polymers,CPs)中最具研究潜力的重要一员,自上世纪90年代以来,经历了飞速的发展。在这个过程中,研究者们对其纷繁复杂的结构做了系统、深刻的研究总结,并逐渐将研究重心过渡至挖掘它们的潜在应用价值上。具有气体吸附分离、分子识别、催化、磁性等优良性能的功能性MOFs被广泛构筑、研究。MOFs自组装合成是一个复杂的反应过程,在众多影响因素中,有机配体由于其分子尺寸不同、具有不同的官能团和配位点及对称性的差异等,在决定目标产物的结构和性能时扮演了非常重要的角色。尤其是具有灵活配位模式的刚性多羧酸配体和官能化修饰的具有多配位点的N-杂环羧酸类配体往往能构筑结构多变,性能优异,骨架稳定的MOFs。此外,在改良功能性配合物性能时,中心金属离子的电子结构对其性能起到了决定性的作用,镧系金属离子因为其独特的4f轨道而在磁性和荧光等方面具有的特殊性能而被化学家们广泛用于开发高性能的MOFs材料。遵循以上的构筑策略,本论文选用了带硝基的联苯-3'-硝基-3,4',5-三羧酸(H3L1)配体和两个同分异构的吡啶羧酸配体2-(3,5-间苯二甲酸)-5-吡啶甲酸(H3L2)和3-(3,5-间苯二甲酸)-6-吡啶甲酸(H3L3)配体为构筑基元用来设计合成功能性配合物。在晶体工程分子自组装原理的指引下,采用水热溶剂热法成功合成了以下配合物:[LnL1(H2O)3].3H2O·0.75DMF(1-7)(Ln=Dy(1),Eu(2),Tb(3),Gd(4),Er(5),Ho(6),和 Yb(7));[Ln2(L2)2(H2O)4(DMA)].DMA·3H20(Ln= Dy(8),Eu(9),Ho(10),Tb(11),Gd(12),Yb(13)和Er(14);[Zn4(L1)2(H2O)(OH)2](15);[Zn3(L3)2(H2O)]·4H20(16);[Zn3(L3)2(bipy)(H2O)6]2H20(17)。配合物1-7和8-14分别为两个系列典型的Ln-MOFs,各自具有相同的结构,并具有优良的磁学和光学性质。单晶X射线研究表明,配合物15是一例具有罕见的7核金属簇的结构,相邻的两个金属簇利用配体连接,构筑起三维的空间结构。配合物16和17是利用d1()电子组态金属与H3L3设计合成的,因此都具有一定的荧光性能。本论文对合成的配合物进行了 X-射线粉末衍射(PXRD)、元素分析、红外光谱(IR)和热重分析(TGA)等基本表征。此外,对以上提及性质做了系统的探究。
[Abstract]:Metal-organic frameworks (MOFs), as one of the most promising coordination polymers, have experienced rapid development since the 1990s.In this process, the researchers made a systematic and profound summary of their complicated structures, and gradually transferred the research focus to excavating their potential application value.Functional MOFs with excellent properties such as gas adsorption and separation, molecular recognition, catalysis and magnetism have been widely constructed. Self-assembly synthesis of MOFs is a complex reaction process. Among many factors, organic ligands have different molecular sizes.Different functional groups, coordination points and symmetry play a very important role in determining the structure and properties of the target products.In particular, rigid polycarboxylic acid ligands with flexible coordination modes and N-heterocyclic carboxylic acid ligands with functionalized functionalization are often able to construct MOFs with variable structure, excellent performance and stable skeleton.In addition, the electronic structure of the central metal ions plays a decisive role in improving the properties of the functional complexes.Lanthanide metal ions have been widely used by chemists to develop high performance MOFs materials due to their special magnetic and fluorescent properties due to their unique 4f orbitals.Follow the above construction strategy,In this thesis, the ligand of biphenyls with nitro biphenyls, biphenyls, nitro, tricarboxylic acid, trichlorocarboxylic acid, and two isomerized pyridine carboxylic acid ligands, 2-Py, 5-pyridine-5-pyridinic acid, H3L2) and 3-triphenylalanedioic acid-6-pyridinoic acid (H3L3), were used as constructors for the construction of the ligands in this thesis.Design and synthesis of functional complexes.鍦ㄦ櫠浣撳伐绋嬪垎瀛愯嚜缁勮�呭師鐞嗙殑鎸囧紩涓�,閲囩敤姘寸儹婧跺墏鐑�娉曟垚鍔熷悎鎴愪簡浠ヤ笅閰嶅悎鐗�:[LnL1(H2O)3].3H2O路0.75DMF(1-7)(Ln=Dy(1),Eu(2),Tb(3),Gd(4),Er(5),Ho(6),鍜，

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