Luminescent Coordination Soft Matters:Emission And Chemosensing

Part I:The research on organic light-emitting diodes (OLEDs) has drawn tremendous attention of scientists since the end of the1980s. Compared to the first and second generation displays, OLEDs have many advantages, such as self-emitting property, high luminous efficiency, full color capability, wide viewing angle, high contrast, low power consumption, low weight, potentially large area color displays and flexibility. The typical OLED device is composed of a cathode, an electron transport layer, an emitting layer, a hole transport layer and an anode. The study of OLEDs is mainly on the optimization of manufacturing processes and development of new emitting materials.8-Hydroxyquinoline aluminum (Alq3) is an excellent OLED material since it has the properties of high glass-transition temperature (Tg), excellent charge mobility and high luminous efficiency etc. The Alq3is hard to use in industrial manufacturing due to its poor solubility in routine solvents. An Atom Transfer Radical Polymerization (ATRP) initiator based on an8-hydroxyquinoline derivative and a monomer based on a carbazole derivative were synthesized and polymers with various molecular weights were obtained. The optical properties of the polymeric macroligands and their corresponding metal complexes (Al3+and Zn2+) were studied. The complexes showed good solubility in organic solvents, film-forming capability and excellent luminescence properties. Such complexes have the potential to for OLED applications.Part II. Metal ion detection has been an important topic in the fluorescent chemosensor technology. Compared to the traditional methods, the fluorescent chemosensor counterpart has many advantages, such as high sensitivity and selectivity. The macrocycle (S)-6based on binaphthol (BINOL) was synthesized and the fluorescence properties of (S)-6in methanol toward various metal cations were studied. Both Zn2+and Cd2+enhanced the fluorescence of (S)-6mostly at the original emission wavelength and the addition of Hg2+caused a strong emission at a much longer wavelength of λ=570nm, while the others quenched the fluorescence of (S)-6. Furthermore,(S)-6shows an off-on-off fluorescent response toward Hg2+. The time-depended density functional framework (TD-DFT) calculation provides strong evidence regarding to the large red shift in the absorption of the complex of (S)-6and Hg2+. We show that (S)-6is an excellent fluorescent probe since it can detect Hg2+selectively and sensitively.