Metal Ions With 8 - Hydroxyquinoline Derivatives Complex Synthesis And Fluorescence Properties

Not only were the kinds, characteristics and luminescent principles of organic electroluminescent materials as well as the relationship between molecular configuration and the luminescent properties reviewed, but also the advances of electroluminescent materials of quinolinolato complex were summarized and the research prospects of organic electroluminescent materials were viewed. The new complexes of bis(2-phenyl-8-hydroxyquinolato)zinc and 2-phenyl-8 -hydroxyquinolatolithium were synthesized and its luminescent properties were respectively studied in order to father disclose its fluorescence characteristics and to get new organic luminescent materials.The melting point of bis(2-phenyl-8-hydroxyquinolato)zinc with good thermal stability is 270.5 "C . By comparison the luminescent properties of bis (2-phenyl-8-hydroxyquinolato) zinc with bis (8-hydroxyquinolato) zinc, the former not only has a new excitation peak at 465nm, but its emission peak located at 521 run has a red shift about 26 run, compared to that of the later located at 495 ran. It is possibly suggested that the mechanism of different fluorescence properties of both above mentioned is ascribed to the formation of the new transition energy level caused by the substitution of phenyl moiety, which father leads to the change of the HOMO of molecular and narrow the energy gap between HOMO and LUMO, so it results in the appearance of new excitation band and red shift of emission band. In addition, the solvent effects on the fluorescence properties of bis (2-phenyl-8-hydroxyquinolato)zinc in various solvents were studied. According to emission spectra of bis(2-phenyl-8-hydroxyquinolato) zinc in various organic solvents, it is shown that the presentation of blue or red shit of emission band is ascribed to the general solvent effect and the special solvent effect.By comparison of luminescent properties of 2-phenyl-8-hydroxyquinolato lithium with 8-hydroxyquinolatolithium, the former not only has a new excitation peak at 425nm, but its emission peak located at 492 nm has a red shift about 37nm, compared to that of the later located at 455 nm. Not only are these results similar tothat of bis (2-phenyl-8-hydroxyquinolato)zinc with bis (8-hydroxyquinolato)zinc, but the variation of mechanism of luminescent properties for the above two groups are also similar. The difference of fluorescence properties between bis (2-phenyl-8-hydroxyquinolato)zinc and 2-phenyl-8-hydroxyquinolatolithium is probably related to the metal electronegativity.The 2-bisphenyl-8-hydroxyquinoline was synthesized and its fluorescence property was firstly measured. Its emission bands are located at 377, 518.5, and 707.5 nm, respectively. As for its reason, it is possibly suggested that there are conjugated systems with different energy level and the electron transition is occurred.