萘甲酸功能化的聚砜与Eu(Ⅲ)离子所形成的高分子-稀土配合物的制备及其荧光发射特性

Florescence emission character of polymer-rare earth ion complex formed by naphthoic acid-functionalized polysulsone and Eu(Ⅲ)

采用大分子反应法,将萘甲酸(NA)键合在聚砜(PSF)侧链,制得萘甲酸功能化的聚砜PSFNA。以PSFNA为大分子配基,以邻菲罗啉(Phen)为小分子配体,与Eu(Ⅲ)离子配位,分别制备了二元高分子-稀土发光配合物PSF-(NA)3-Eu(Ⅲ)与三元高分子-稀土发光配合物PSF-(NA)3-Eu(Ⅲ)-(Phen)1。采用红外光谱(FT-IR)和紫外吸收光谱(UV)对配合物进行了表征,对配合物的化学结构与发光性能的关系进行了深入研究,并应用Antenna效应理论,从微观机理上分析了实验结果。同时也制备了配合物的固体薄膜,考察了固体薄膜的荧光发射性能。研究结果表明,键合在PSFNA侧链的配基NA能有效地敏化Eu(Ⅲ)离子的荧光发射,大分子配基PSFNA与Eu(Ⅲ)离子所形成的二元或三元高分子-稀土配合物,均能发射出很强的Eu(Ⅲ)离子的特征荧光。但是,键合在PSFNA侧链的配基NA对Tb(Ⅲ)离子的荧光发射无敏化作用,还会发生由中心离子激发态到配基三线态的逆向能量转移。第二配体的协同配位效应使三元配合物的荧光发射强度高于二元配合物。

Naphthoic acid （NA） ligand was attached on the side chains of polysulfone （PSF） by using the poly- mer reaction method,obtaining naphthoic acid-functionalized polysulfone PSFNA. The luminous secondary pol ymer-rare earth complex PSF-（NA）a Eu（ III ） and the ternary complexes PSF-（NA）： Eu（ Ill ）-（Phen）l and PSF- （NA）a Eu（ II1 ）-（Bipy）l were prepared by the coordination of Eu（ III ） ion with PSFNA as a macromolecular lig and small molecular phenanthroline （Phen）, respectively. The complexes were characterized by FT IR and UV absorption spectra, and the relationship between their florescence emission properties and chemical structures was investigated in depth. The corresponding experimental results were explained from the view of micro-mech- anism with antenna effect theory. The experimental results formed by the coordination of PSFNA and Eu（ ]1I ） ion can show that all of the secondary and ternary complexes emit the strong characteristic fluorescence of Eu（ ]]1 ） ion,suggesting that the NA ligand bonded on the side chains of PSFNA can effectively sensitized the fluores cence emission of Eu（ ]]1 ） ion. The NA ligand bonded on the side chains of PSFNA has no sensibilization for the fluorescence emission of Tb（ I]I ） ion,in contrast,a energy back transfer from the excited state of Tb（ I]] ） ion to the triplet state of the NA ligand will occur. The florescence emission intensity of the ternary complex was stronger than that of the secondary complex owing to the synergism coordination effect of the first and second ligands.