3,4-噻吩二羧酸、1,10-邻菲罗啉与稀土配合物的荧光性质及对硝基苯的检测

Fluorescence Properties and the Detection of Nitrobenzene of Lanthanides Complex with 3,4-Thiophenedicarboxylic Acid and 1,10 Phenanthroline

3,4-噻吩二羧酸（3,4-H2tdc）,1,10-邻菲罗啉（phen）和稀土硝酸盐经水热法合成三种配合物Ln2（Htdc）2（tdc）2（phen）2（H2O）4（Ln=Eu 1,Gd 2,Tb 3）,并用X-射线单晶衍射分析方法测定了配合物1-3晶体结构,配合物1-3为双核分子。每个金属离子周围有2个3,4-tdc,1个3,4-Htdc,1个phen和2个配位水分子,配位数为9。配合物1和3在紫外灯下显强红光和绿光,其荧光发射光谱,在619和545 nm出现最大发射峰,分别对应于Eu（Ⅲ）离子的^5D0→^7F2和Tb（Ⅲ）离子的^5D4→^7F5跃迁。配合物2在425 nm观察到来自基于配体的π^＊→π最大发射峰。不同溶剂分子对配合物1荧光有不同程度的影响,基于荧光猝灭机理,配合物1具有选择性检测硝基苯污染物的能力。

3,4-thiophenedicarboxylic acid（3,4-H2tdc） as the first ligand,1,10-phenanthroline（phen） as the auxiliary ligand,three complexes Ln2（Htdc）2（tdc）2（phen）2（H2O）4（Ln=Eu 1,Gd 2,Tb 3） were synthesized with hydrothermal method.Single-crystal X-ray diffraction analysis reveals that complexes 1-3 were isostructural crystallize and both of complexes are binuclear molecules.In the complexes 1-3,the coordination number is nine.Each metal is bound to two 3,4-tdc ligand,one 3,4-Htdc ligand,one phen and two water molecule.Complexes 1 and 3 display the red and green light under UV lamp,corresponding the characteristic peaks from 619 nm（^5D0→^7F2） and 545 nm（^5D4→^7F5）.Complex 2 expresses a broad band at 425 nm is attributed to π^＊→π transition.Furthermore,under the excitation wavelength of 329 nm,the effects of different solvents on complex 1was discussed and complex 1 could be a potential luminescent probe for detecting nitrobenzene through fluorescence quenching mechanism.