Synthesis And Properties Research Of Carbazole Derivatives For Organic Light-emitting Diodes

In recent years, a lot of OLEDs have been reported, but improving materials' fluorescence quantum efficiency, film properties and stabilities are still the researchers' purpose. Carbazole derivatives are a kind of important organic electroluminescent material which includes a nitrogen atom as a strong electronic donor. Carbazole derivatives also have good hole-transport property, thermal and morphological stabilities. In this dissertation, molecules based on indolo[3,2-b]carbazole derivatives have been synthesized and characterized. Several tests have been used to explore carbazoles optical properties.We designed three unreported substituted indolo[3,2-b]carbazole compounds--1,2 and 3. They were synthesized by acid-catalyzed condensation of indole with formoxyl aromatic compounds. The chemical structures were confirmed by 1H NMR and high resolution mass spectrometry. The optical properties were studied by UV-vis absorption spectroscopy and fluorescence emission spectra. The maximum absorption wavelengths of 1,2 and 3 were 287 nm,289 nm and 270 nm. And the fluorescence emission wavelengths of them were 432 nm, 435 nm and 430 nm. The fluorescence quantum yields were also calculated and compound 2 gets the highest which is 0.78. The highest occupied molecular orbital energy of 1,2 and 3 were-4.80 e,-4.70 eV and-4.84 eV which were calculated by cyclic voltammetry.