Synthesis And Application Research Of The Carbazole With Conjugated Aromatic Group For Organic Light-emitting Materials

Organic light-emitting diodes(OLED) have been attracted more and moreinterests with particular advantages such as excellent luminescence properties，vastprospect applicationThe currently major efforts research is focused on searching for newlight-emitting materials and obtaining higher performance OLEDs．Up to now，redand blue light-emitting materials show poorer performance than that of green ones inred-green-blue tricolour phosphors used in fabrication of OLEDs．The carbazole derivative is a kind of cavity transmission groups．Recently，seriesof productions of the carbazole derivative show high cavity transmission ability，highluminescence efficiency and glass transformation temperature．So we chose carbazolederivatives as the base for the research hoping to synthesize some OLED materialswith good light-emitting ability and high thermal stabilities．Based on the full and careful investigation of the literature，we carded out thework including the following aspects：1．6carbazole derivatives were obtained by using Ullmann reaction．Thestructures of these compounds were characterized by GC,LC,MS,IR and so on．2．Their optical properties were characterized by UV,CV and their thermalproperties were determined by DSC. 3．Compared their properties and molecular structures based on the initialcharacterization，it was suggested that：(1) calculate the energy gape of9-phenyl-9H-carbazole,9-(anthracen-2-yl)-9H-carbazole,9-(phenanthren-9-yl)-9H-carbazole and9-(triphenylen-2-yl)-9H-carbazole based on the ultraviolet absorption spectrum andformule Eg（eV）=hc/λonset≈1241/λonset,9-(triphenylen-2-yl)-9H-carbazole has thebiggest Eg(3.372eV)，it can be used as EL material for OLED. Though the analysis ofthe data，we did not get the relation between the energy gape and the conjugatedaromatic；(2)The HOMO of four kinds of materials are between5.1～5.2eV，and thereLUMO are1.8～2.2eV,these materials can be expected as the blue host material ofthe electroluminescent material;(3)From all the materials,9-(anthracen-2-yl)-9H-carbazole has better thermal stability,the melting point of this material is247.97℃，the melting point of9-phenyl-9H-carbazole and9-(phenanthren-9-yl)-9H-carbazoleare94.32℃and94.10℃,respectively，we did not found the melting point of the9-(triphenylen-2-yl)-9H-carbazole;(4) The compounds have good solubility inorganic，which is very advantaged for OLED device fabrication using spin-coatingmethod．...