A class of orange-light iridium complexes and their application in organic electro-whitening or orange-light devices

Abstract

The invention discloses organic optical iridium coordination compounds and application thereof in an organic electro-generated white or orange optical device. The orange optical iridium coordinate compounds have a structural formula as formula 1 or formula 2 which is shown in the specification, wherein R1 can be trifluoromethyl or pentafluoroethyl, R4 can be trifluoromethyl or pentafluoroethyl or R1=R4, R2 is selected from hydrogen, methyl, ethyl and halogen or halogen-substituted methyl or ethyl, R3 is independently selected from hydrogen, methyl, ethyl, halogen or halogen-substituted methyl or ethyl or R2=R3, and the halogen is fluorine, chlorine, bromine or iodine. The invention has the advantages as follows: a fluorine-containing modified iridium coordination compound can be used for effectively lowering vibrating frequency, reducing non-radiative transition and increasing electroluminescence efficiency; a film prepared by using a fluorine atom-containing modified coordination compound has better feature; self-quenching behaviors are restrained by steric hindrance of CF3; and charge transfer balance performance is increased by very good current carrier transmission performance, so that an efficient doped organic electro-generated luminescent device can be manufactured.

Description

technical field [0001] The invention belongs to the technical field of organic electroluminescence, and in particular relates to the synthesis of orange iridium complexes based on 2-phenylbenzothiazole nitrogen heterocycles as ligands and the use of such materials in white organic light-emitting diodes (WOLEDs) in the application. Background technique [0002] Heavy metal complexes with phosphorescent emission have attracted sufficient attention in organic light-emitting diodes (OLEDs) due to their good color purity, high quantum efficiency, short phosphorescence lifetime, and high photothermal stability. In particular, modified cyclic metal ligands (C ∧ N ligand) can control the luminescence of the complexes to be tunable in the entire visible light range, which is beneficial to realize full-light and white-light displays. Tuning phosphorescence emission can usually be achieved by changing the C ∧ Substituent groups on N ligands, such as ppy(2-phenyl-pyridinato-C 2 ,N),...

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Problems solved by technology

But when an electron-withdrawing substituent is introduced into the 5-position, the weak π-donating effect of the fluorine atom on the electron density of the HOMO will counteract the electron-withdrawing effect of the fluorine atom, thus reducing the bandgap width.

Although these methods for modifying phosphorescent emission by introducing electron-donating or electron-withdrawing groups have been recognized, the development of phosphorescent materials that can easily modify emission by modifying the electronic structure of ligands has not yet reached a satisfactory level.

[0004] In addition, the LUMO energy level of the 2-phenylbenzothiazole iridium complex is relatively high. If no modification is made, the electrons will have a higher potential barrier when injected from the cathode.

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