基于含吡啶基多羧酸配体构筑的配位聚合物的合成、结构及性质研究

发布时间：2018-07-10 08:04

  本文选题：含吡啶基多羧酸 + 溶剂热合成　； 参考：《内蒙古大学》2017年硕士论文

【摘要】：近些年来,配位聚合物因结构的独特性和新颖性使其在非均相催化、分子或离子识别、分子磁体、荧光材料和非线性光学材料等诸多领域具有广阔的应用前景,因此合理的设计和构筑配位聚合物依然是研究者们的科研热点。本文以含吡啶基多羧酸和有机羧酸为配体,通过调节金属盐与配体比例、反应温度及时间、溶剂组成等条件,在水热、溶剂热条件下进行自组装合成了 15个稀土或过渡金属配位聚合物,并对它们的结构和相关性质进行了研究。以4-(吡啶-3-氧基)-邻苯二甲酸(H2ppda)为主配体,分别与对苯二甲酸(H2bdc)、联苯二甲酸(H2pbdc)、草酸(H2C204)等辅助配体,在水/乙醇体系中,成功构筑了三个系列14例结构新颖的镧系配合物。配合物均为二维层状构型,未配位的醚键O原子活性位点存在于二维层中,由于辅助配体轴向长度的不同,所以形成了三种不同大小的平面网格,网格的大小分别为:5.981 × 11.387 A,6.031 × 15.667 A,6.263×6.041 A;二维层均通过分子间氢键构成三维超分子结构。三个系列配合物的Ln-O平均键长均随着Ln(Ⅲ)离子半径的减小而减小,体现了镧系收缩效应。测试了配位聚合物1-14的热重、红外、元素分析和PXRD等性质;此外,发现3-Gd配合物离子之间具有铁磁性相互作用;同时,对发光的配位聚合物1-2,4-5,7-8,10-11,13-14进行了荧光性质的测定;研究发现,它们均表现出稀土的特征发射峰。其中配合物4-Tb不仅可以作为检测痕量硝基苯(NB)的荧光探针,而且还可以选择性检测Fe3+和Cr2O72-离子;配合物9-Tb可以作为选择性检测Al3+离子和CO32-离子的双功能荧光探针。利用X-射线光电子能谱、X-射线粉末衍射、紫外可见吸收光谱对荧光检测的机理进行了较详尽的研究,并且分别对硝基苯分子、一些金属离子和无机阴离子不同的荧光探针机理进行了详细的解释和推断。通过4-(2,2';6',2"-三吡啶)-4'-1,2-邻苯二甲酸(H2tbda)配体合成了一个配位聚合物,其分子式为[Zn(tbda)]n(15),配合物15为一维链状结构,通过π…π相互作用形成二维结构,研究了配合物15的热稳定性、红外、元素分析、PXRD、荧光等性质。发现15具有很高的热稳定性。
[Abstract]:In recent years, coordination polymers have been widely used in heterogeneous catalysis, molecular or ion recognition, molecular magnets, fluorescent materials and nonlinear optical materials due to their unique structure and novelty. Therefore, rational design and construction of coordination polymers is still a hot research topic for researchers. In this paper, with pyridyl polycarboxylic acid and organic carboxylic acid as ligands, by adjusting the ratio of metal salt to ligand, reaction temperature and time, solvent composition, etc. Fifteen rare earth or transition metal coordination polymers were synthesized by solvothermal self-assembly and their structures and properties were studied. With 4- (pyridine-3-oxy) -phthalic acid (H2ppda) as the main ligand and terephthalic acid (H2bdc), biphenyl dicarboxylic acid (H2pbdc), oxalic acid (H2C204) as auxiliary ligands, three novel lanthanide complexes were successfully constructed in water / ethanol system. All the complexes are of two dimensional layered configuration. The active sites of O atoms of uncoordinated ether bonds exist in the two dimensional layers. Due to the different axial lengths of the auxiliary ligands, three kinds of planar grids of different sizes have been formed. The mesh size is 5.981 脳 11.387 An 6.031 脳 15.667 An 6.263 脳 6.041 A. Two-dimensional layer is composed of three-dimensional supramolecular structure by intermolecular hydrogen bonding. The average Ln-O bond length of the three series of complexes decreases with the decrease of Ln (鈪，

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