The Synthesis And Properties Of Organic Light-emitting Material

Small organic molecules are the targets of research in this paper. A series of organic light-emitting molecules are synthesized and their optical properties are researched.First, "green emission tail" (500-600 nm) from fluorene-based oligomers or polymers limits their applications in organic light emitting diodes (OLEDs). It is necessary to design new type of fluorene-based compounds which can suppress the appearance of "green emission tail". Based on this, we synthesized a series of aryl-substituted trispirobifluorenes. Their electrochemical, optical properties and thermal behaviors were investigated. Furthermore, "green emission tail" is not observed through annealing test.Second, efficient and stable blue electrophosphorescence remains a challenge in part because of the lack of appropriate organic charge transporting host materials with high triplet energy (E_T). Here, we synthesized three triarylphosphine oxides and investigated their properties. A few OLEDs were fabricated to investigate their properties of being electron transporting and host materials.Third, multifunctional materials play an important role in determining the stabilities,efficiency and lifetime of OLEDs. We synthesized several multifunctional compounds with carbazole as donor and 1,3,4-oxadiazole as acceptor. Their optical properties and solvation effect were investigated. It shows that there is a big dipole moment in their excited state.Fourth, relations of structure-fluorescence properties are of an important subject in material chemistry. In this paper, we synthesized some difluorene derivatives. Their fluorescence properties are investigated. Relations of fluorescence properties and structure were summarized.