基于4-(2,4-二羧基苯氧基)邻苯二甲酸配体的锌配位聚合物的合成、结构及其荧光传感性能

基于H₄dpa和bpy(H₄dpa=4-(2,4-二羧基苯氧基)邻苯二甲酸,bpy=4,4''-联吡啶)为配体,在水热条件下设计、合成了金属锌配位聚合物(Zn-CP)Zn(H₂dpa)(bpy)_1.5]_n (1),并用元素分析、红外光谱、X射线单晶衍射等对其进行了结构表征。在1中相邻Zn²⁺与H₂dpa^2-离子和bpy配位形成的一维双链结构,相邻的一维双链通过氢键作用扩展形成三维超分子网结构。荧光研究表明:1是一种灵敏度高、选择性好、多响应的荧光传感器,可用于农药和硝基爆炸物的检测。有趣的是,2,4,6-三硝基苯(TNP)和嘧霉胺(Pth)对1的荧光发射显示出明显的猝灭效果,而抑霉唑(Ima)对1有荧光增强效果。此外,通过紫外可见吸收光谱、荧光寿命以及X射线光电子能谱探究了1的荧光传感机理。

Synthesis, structure, and fluorescence sensing properties of zinc coordination polymers based on 4-(2,4-dicarboxylic phenoxyl) phthalic acid ligand

A zinc coordination polymer(Zn-CP)based on H₄dpa and bpy ligands (H₄dpa=4-(2,4-dicarboxylic phenoxyl) phthalic acid, bpy=4,4''-dipyridine), namelyZn(H₂dpa)(bpy)_1.5]_n (1), has been hydrothermal synthesized and structurally characterized by elemental analyses, IR spectroscopy and single-crystal X-ray diffraction analysis. 1 shows 1D double chain based on Zn²⁺ ion, H₂dpa^2- and bpy ligand. The adjacent 1D double chains further expand into a 3D supramolecular network through hydrogen bonding. Fluorescence studies show that 1 is a fluorescence sensor with high sensitivity, good selectivity, and multiple responses, which can be used for the detection of pesticides and nitro explosives. Interestingly, 2,4,6-trinitrobenzene (TNP), and pyrimethanil (Pth) had an obvious quenching effect on the fluorescence emission of 1, while imazalil (Ima) had an enhancement effect on the fluorescence of 1. In addition, the fluorescence mechanism was investigated by means of UV-Vis absorption spectrum, fluorescence lifetime, and X-ray photoelectron spectroscopy.