Synthesis Of A New Series Of Cyclometalated Iridium Complexes Based On5-aryl-8-hydroxyquinoline And Phenanthrene Derivatives As Ligands And Red To Near-infrared Luminescent Properties

8-hydroxyquinoline metal complexes have good luminescent properties, film forming, no angular dependence, low drive voltage and become a research hotspot in recent years. They have been applied widely in military, industry, and daily life. Recently, near-infrared (NIR) OLEDs have received attention due to their potential application in medicine, biological sensors, communications. The materials used in NIR OLEDs have been limited in number, most of them being organic complexes containing trivalent rare earth ions, such as Er3+, Nd3+, Tm3+and Y3+. Only a few organic materials containing no rare earth ions display electroluminescence in the NIR region.In this paper, a new series of bis-2-phenylpyridine-5-substituted aryl-8-hydroxyquinoline iridium(Ⅲ) complexes ((C^N)2IrQp) have been synthesized, where C^N is2-phenylpyridine and Qp represents the5-substituted arly-8-hydroxyquinoline and their chemical structure, thermal stability, energy gap of Eg and photophysical properties are characterized by1HNMR,13CNMR, MS, thermal analysis, UV-VIS, photoluminescence spectra and cyclic voltammetry.These complexes produce the red phosphorescent emission and the intensity of the emission peaks at666and687nm shows nearly same at the room temperature, which is different from the properties of past synthesized8-hydroxyquinoline iridium complex. Also, we find that the absorption and emission properties of the complexes are mainly affected by the impact of the benzene ring in5-site of8-hydroxyquinoline, whereas the substituents in benzene ring have little effect on the photophysical properties of the complexes. If5site of8- hydroxyquinoline have been substituted by amino group, the emission wavelength will be blue-shifted. Moreover, the luminescence of the complexes based10-hydroxybenzo[h]quinoline as ligand will blue shift. So they are expected to become a new sort of red phosphorescent material, because intensive luminescence at room temperature.Furthermore, in this article, a serie of iridium complexes using phenanthrene derivatives as the main ligand is also synthezized, and the structure and properties of the series of the complexes are tested. Through the PL spectra test, the emission wavelength of the series of complexes in the near-infrared light-emitting wavelength ranges from690nm to703nm, and the half of peak width is relatively narrow (56nm,58nm), which means that the light-emitting is of high purity; TGA test results of the series of complexes show good thermal stability. These series of iridium complexes are expected to become a sort of excellent near-infrared organic light-emitting materials.In this paper, the research mainly concentrates on the following aspects:(1) A serie of cyclometalated iridium complexes using8-hydroxy quinoline derivative as the main ligand cyclometalated iridium complexes were synthesized;(2) A serie of iridium complexes using phenanthrene derivatives as the main ligand is synthesized;(3) Structure and performance of these two series of complexes have been tested;(4) The structure and photophysical properties of the complexes have been systematically analysised.