Research Of Low-cost Phosphorescent Materials For OLED

With the development of organic light emitting device(OLED),the study in light-emitting materials have been recieved more and more attention.In the past decades,Iridium as well as other precious metals were usually used as phosphor in OLED.However,precious metals complexes exist some limitations,such as high cost,less resources and environmental pollution.In this aim,a great deal of interest for developing low-cost electroluminescent devices.Based on these requirements,Cu(I)complexes which are Earth-abundant and environment-benignancy have been identified as favorable candidates that could advantageously replace the well-established iridium complexes.Similar to the Ir complexes,Cu(I)complexes as phopherescent material uesd in OLED also have maximum internal quantum efficiency(IQE)100% in theory.In this paper,a series of phosphorescent mateials were synthesized at room temperature based on Cu(I)complexes by the design and synthesis of ligands.On this basis,the properties and the crystal structures of these compounds have been further investigated to reveal the relationships between the stuctures and properties.The specific contents are as follows:1.Xantphos Complexes: Series of complexes 1-9 have been successfully synthesized by using Xantphos and 3-PBO,3-CNPy,4-CNPy,2-apy,3-apy,8-Hhq.The single crystal X-ray diffraction structure shows that all complexes are ionic mononuclear complexes.Besides,it has been found that 7-9 are allomorphic type complexes.In comparison to other complexes,the emission intensity of 3-apy is significantly higher.The UV-Vis absorption showed that all transitions are MLCT character.2.BINAP Complexes: Series of complexes 10-18 have been successfully synthesized by using BINAP and 4-PBO,3-apy,2-apy,BTA,4-CNPy,4,4'-bipy,1Htri.The single crystal X-ray diffraction structure shows that all complexes are ionic mononuclear complexes.Besides,it has been found that 15,16 are allomorphic type complexes.In comparison to other complexes,the emission intensity of 3-apy is significantly higher.The UV-Vis absorption showed that all transitions are MLCT character.3.The control of material light-emitting layer properties: In this paper,light-emittinglayers are prepared by PMMA and PVP mixing with complex 19.It is found that complex 19 display good thermal stability as well as luminescent property.