合成了高分子金属配合物聚8-羟基喹啉镓(Gaqq3)n。利用红外吸收光谱、X射线衍射谱(XRD)研究了配合物的分子结构、物相结构;利用热重(TG)分析研究了配合物的热稳定性;利用紫外吸收光谱、荧光激发和发射光谱研究了该配合物的光物理性能。结果表明:(Gaqq3)n的热分解温度为443.6℃,具有较高的热稳定性。(Gaqq3)n的紫外吸收带位于250~500nm,存在较强的带尾吸收,表明禁带中存在带隙缺陷态。(Gaqq3)n的荧光激发带位于380~456nm,荧光发射峰位于568nm,为橙红光发射。光学带隙2.49eV。与Gaq3相比,荧光强度有所减弱,这是由于次甲基相连的两个喹啉环的扭曲导致了(Gaqq3)n的刚性和共平面性不好;由于分子共轭体系的增大,使(Gaqq3)n分子的π电子更加离域化,导致了荧光发射峰发生了红移。(Gaqq3)n有望在有机电致发光器件和有机光伏器件中得到应用。
A ligand 5,5'-methylene-bis (8-hydroxyquinoline) (Hqq) was synthesized by condensation reaction at low temperature and was subsequently coordinated to gallium ions to prepare the polymer of tis(5,5'-methylene-bis (8-hydroxyquinoline)gallium (Gaqq3)n. Both chemical structure and phase structure of the ligand and complexes were characterized by Infrared absorption spectrum and X-ray diffraction (XRD). The thermal stability of the complexes was studied by thermogravimetry (TG). The photo-physical properties of the complexes were investigated by ultraviolet absorption spectrum (UV), fluorescence excitation spectrum and emission spectrum. The result indicated that (Gaqq3)n is a thermally stable material, whose decomposition temperature is 443. 6 ℃. The ultraviolet absorption bands of (Gaqq3)n are in the range of 250-500 um, with a relatively strong band tail absorption between 500 and 650 nm, which shows that the band-gap defect states exists in the forbidden band. The fluorescence excitation band of (Gaqq3)n is located at 380-456 um, and (Gaqq3)n. emits orange-red fluorescence with the emission peak at 568 nm, which shows that the fluorescence emission of (Gaqqa)n is mainly attributed to the charge transfer transitions from phenol to ring pyridine ring, while the π→π^* transition of benzene ring is deactivated by non-radiative transition, and makes no contribution to fluorescence emission. (Gaqq3)n optical band gap is 2.49 eV. Compared with the fluorescence emission peak of Gaq3, the fluorescence intensity of (Gaqq3)n decreases, which is attributed to the distortion of the two quinoline rings connected to the methylene, hence leads to the poor rigidity and coplanarity of (Gaqq3)n, thus affects fluorescence emission intensity. Because of the extending of the molecular conjugation system, π electron of (Gaqq3)n is more delocalized, resulting in the redshift of fluorescence emission peak. (Gaqq3), is expected to be applied in organic ligh