The Design, Synthesis And Properties Of New Blue Light Emitting Organic Materials

As one of the three primary emissive color (red, green and blue) materials utilized in full color organic light-emitting devices, blue organic electroluminescent material has always been a hot spot in the field of organic photoelectric functional materials. The derivatives of carbazole, triphenylamine and indolo[3,2-b]carbazole designed as blue-light chromophore, have drawn much attention duo to their unique structures and excellent luminous properties in the electroluminescence. Based on a overall investigation of the history and current developing situation of carbazole, triphenylamine, indolo[3,2-b]carbazole used as the blue organic electroluminescent materials, we have designed and synthesized a series of their derivatives. And we studied the properties and the application in device, which provided both experimental and theoretical referrenee to the synthesis of novel organic photoelectric functional materials. The main research contents are elaborated as follows:(1) On the basis of investigation and summarization of literatures on organic electroluminescence materials, we briefly described OLED and the structure of it, introduced the current research status of carbazole, triphenylamine and indolo[3,2-b]carbazole used as blue light emitting materials, respectively. And come up with the design ideas for the dissertation based on these.(2) Successfully synthesized fourteen compounds containing six-member ring structure in a chair conformation of carbazole and triphenylamine derivatives. All the complexes were characterized by1H-NMR,13C-NMR, ESI, FT-IR. The crystal structures of ks2and ss2were obtained, and the mechanism of their cyclization reaction was figured out. By investigating the properties of UV-Vis, fluorescence, thermal stability and the data of electrochemistry of the compounds, the results showed that two types of the derivatives were excellent blue light emitting materials with preferable thermal stability. According to the data of UV-Vis and electrochemistry, we got their HOMO and LUMO energy level values that were consistent with theoretical calculation, which can provide reference for OLEDs.(3) Via Fischer indolo reaction, Vilsmeier reaction and Friedel-Crafts acylation reaction, several indolo[3,2-b]carbazole derivatives were obtained and characterized by1H-NMR, MALDI-TOF MS. We got the crystal of YK2, YK3, YK4, and analysed the structures of them.(4) We have made compounds km2, sb2and YK2as light-emitting layer, and applied them in electroluminescence device and preliminary study their electroluminescent characteristics. The results showed that the device’s light-emitting properties are closely related to hole-transporting layer, electronic-transporting layer, light-emitting layer as well as the method and thickness of forming film into light-emitting layer. All of these provided an efficient experimental reference and data support for compounds being applied in electroluminescence devices in future.