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EP-4741409-A1 - FUSED-RING CARBAZOLE TETRADENTATE METAL PLATINUM (II) COMPLEX AND USE THEREOF, AND ELECTRONIC DEVICE

EP4741409A1EP 4741409 A1EP4741409 A1EP 4741409A1EP-4741409-A1

Abstract

The present invention relates to the field of organic electroluminescence, and in particular to a fused-ring carbazole tetradentate metal platinum (II) complex and a use thereof, and an electronic device. According to the present invention, the interaction between molecules is reduced by means of the introduction of diphenyl, and a fused-ring carbazole system is introduced at different positions of carbazole to improve the component proportion of a localized state (LE) in an excited triplet state of a cyclic tetradentate platinum (II) complex, so that the cyclic tetradentate platinum (II) complex has a low shoulder peak to improve the purity of luminescence of material molecules. Materials involved in the present invention all have good chemical stability and thermal stability, and are easy to prepare evaporated OLED devices. The combination with a fluorescent doping material can balance transport of holes and electrons, and energy transfer between a subject and an object is more efficient. An organic electroluminescent device manufactured by using the compound of the present invention as a luminous layer has markedly improved current efficiency, markedly prolonged service life, and a markedly reduced tum-on voltage. In particular, the joint use with boron-containing compounds sensitized by phosphorescence materials can improve the purity of luminescence of devices.

Inventors

  • LI, GUIJIE
  • YAO, HUANHUAN
  • SHE, YUANBIN
  • CHU, Qingshan
  • WU, KONGWU

Assignees

  • Zhejiang University of Technology
  • Zhejiang Huaxian Photoelectricity Technology Co., Ltd

Dates

Publication Date
20260513
Application Date
20231204

Claims (14)

  1. A fused-ring carbazole tetradentate platinum(II) complex, characterized in that , the complex has a general structure selected from formulas (I) to (V): wherein in formulas (I) to (V), X is selected from C, O and S; R 1 -R 9 each independently represent from mono to maximum allowable substitution, or no substitution; and R 1 -R 9 are each independently selected from the group consisting of: hydrogen, deuterium (D), halogen, CN, C1-C30 alkyl, C1-C30 deuterated alkyl, C1-C30 haloalkyl, C1-C30 cycloalkyl, C1-C30 heterocycloalkyl, C6-C60 aryl, a C6-C60 fused-ring aromatic hydrocarbon group, C6-C60 heteroaryl, a C6-C60 fused heterocyclic aromatic hydrocarbon group, C6-C60 arylamino, and combinations thereof, in a case where a heteroatom is involved, the heteroatom being selected from N and O.
  2. The fused-ring carbazole tetradentate platinum(II) complex according to claim 1, characterized in that , R 1 and R 6 -R 9 are each independently selected from the group consisting of: hydrogen, deuterium, CD 3 , F, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, tert-pentyl, n-hexyl, isohexyl, sec-hexyl, tert-hexyl, n-heptyl, isoheptyl, sec-heptyl, tert-heptyl, n-octyl, isooctyl, sec-octyl, tert-octyl, n-nonyl, isononyl, sec-nonyl, tert-nonyl, phenyl, and combinations thereof.
  3. The fused-ring carbazole tetradentate platinum(II) complex according to claim 1, characterized in that , R 1 and R 6 -R 9 are each independently selected from the group consisting of: hydrogen, deuterium, CD 3 , F, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, phenyl, and combinations thereof.
  4. The fused-ring carbazole tetradentate platinum(II) complex according to claim 1, characterized in that , R 2 -R 5 are each independently selected from the group consisting of: hydrogen, deuterium, CD 3 , F, CF 3 , methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, phenyl, naphthyl, pyridyl, quinolinyl, cyclopentane, cyclohexane, five-membered heterocycle, diphenylamine, and combinations thereof.
  5. The fused-ring carbazole tetradentate platinum(II) complex according to claim 1, characterized in that , the complex is any one selected from chemical structures shown below, wherein D represents deuterium:
  6. An application of the fused-ring carbazole tetradentate platinum(II) complex according to any one of claims 1 to 5 in an electronic device, wherein the electronic device comprises one or more of an organic electroluminescent device, an organic integrated circuit, an organic field-effect transistor, an organic thin-film transistor, an organic light-emitting transistor, an organic solar cell, an organic optical detector, an organic photosensor, an organic field-quench device, a light-emitting electrochemical cell and an organic laser diode.
  7. An organic electroluminescent device, characterized in that , the organic electroluminescent device comprises a cathode, an anode and an organic functional layer between the cathode and the anode, wherein the organic functional layer contains the fused-ring carbazole tetradentate platinum(II) complex according to any one of claims 1 to 5.
  8. An organic electroluminescent device, characterized in that , the organic functional layer includes a light-emitting layer, wherein the light-emitting layer contains the fused-ring carbazole tetradentate platinum(II) complex according to any one of claims 1 to 5.
  9. The organic electroluminescent device according to claim 8, characterized in that , the light-emitting layer further includes a fluorescent dopant material, and the fluorescent dopant material is a boron-containing compound.
  10. An organic optoelectronic device, characterized in that , the organic optoelectronic device comprises: a substrate layer; a first electrode disposed on the substrate; an organic light-emitting functional layer disposed on the first electrode; and a second electrode disposed on the organic light-emitting functional layer, wherein the organic light-emitting functional layer contains the fused-ring carbazole tetradentate platinum(II) complex according to any one of claims 1 to 5.
  11. The organic optoelectronic device according to claim 10, characterized in that , the organic light-emitting functional layer further includes a fluorescent dopant material, and the fluorescent dopant material is a boron-containing compound.
  12. A composition, characterized in that , the composition contains the fused-ring carbazole tetradentate platinum(II) complex according to any one of claims 1 to 5.
  13. A formulation, characterized in that , the formulation contains the fused-ring carbazole tetradentate platinum(II) complex according to any one of claims 1 to 5.
  14. A display or lighting apparatus, characterized in that , the apparatus comprises at least one organic electroluminescent device each according to any one of claims 7 to 9.

Description

TECHNICAL FIELD The present disclosure relates to the field of organic electroluminescence, specifically to a fused-ring carbazole tetradentate platinum(II) complex and an application thereof, and an electronic device. BACKGROUND Organic light-emitting diodes (OLEDs) represent a new generation of full-color display and lighting technology. Compared to the liquid crystal display which suffers from slow response, narrow viewing angle, necessity for backlight and high energy consumption, OLEDs as self-luminous devices offer advantages such as no need for backlight, high energy efficiency, low drive voltage, quick response, high resolution and contrast, wide viewing angle and excellent low-temperature performance; and OLED devices may be fabricated to be thin and into flexible structures. In addition, OLEDs further offer advantages such as low production cost, simple manufacturing process and suitability for large-format products. Therefore, OLEDs possess broad and significant application prospects in high-end electronic products and the aerospace fields. With a gradual increase in investment, further in-depth research and development and upgrading of production equipment, OLEDs will have extensive application scenarios and promising development potential in the future. The core of the development of OLEDs lies in design and development of light-emitting materials. At present, light-emitting layers of OLED devices in use almost exclusively employs a host-guest light-emitting system, i.e., doping a host material with a guest light-emitting material. An energy gap of the host material is typically higher than that of the guest light-emitting material, such that energy is transferred from the host material to the guest light-emitting material, thereby leading to excitation and subsequent light emission of the guest light-emitting material. Common organic phosphorescent guest materials are predominantly complexes of heavy metals such as iridium(III), platinum(II) and palladium (Pd)(II). Commonly used phosphorescent organic materials 3,3'-bis(9-carbazolyl)-biphenyl (i.e., mCBP) and 2,6-bis(9-carbazolyl)-pyridine (i.e., 2,6-mCPy) possess high efficiency and high triplet energy levels, and when the materials are used as organic materials, triplet energy can be effectively transferred from the light-emitting organic materials to guest phosphorescent materials. However, mCBP exhibits high hole mobility but poor electron transport capability, and 2,6-mCPy suffers from inadequate hole transport. This causes charges in the light-emitting layers to be unbalanced, resulting in a decrease in current efficiency of devices. Moreover, heavy-metal phosphorescent organic complexes in use are mainly cyclometalated iridium(III) complex molecules, whose variety is limited. The abundance of platinum in the Earth's crust and the annual global production of platinum are both approximately ten times greater than those of iridium; and the price of IrCl3-H2O used for preparing iridium(III) complex phosphorescent materials is significantly higher than that of PtCl2 used for preparing platinum(II) complex phosphorescent materials. Additionally, the preparation of the iridium(III) phosphorescent materials involves four steps: preparation of an iridium(III) dimer, ligand exchange of an iridium (III) intermediate, synthesis of a mer-iridium(III) complex, and isomerization from mer- to fac-iridium(lll) complex. This substantially reduces an overall yield, greatly decreases utilization ratio of a starting material IrCl3·H2O, and consequently increases a production cost of the iridium(lll) phosphorescent materials. In contrast, the preparation of the platinum(II) complex phosphorescent materials consists of just one step: ligand metallation. This process affords a high utilization ratio of platinum, thereby further reducing a production cost of the platinum(II) complex phosphorescent materials. In summary, the production cost of the platinum (II) complex phosphorescent materials is much lower than that of the iridium (III) complex phosphorescent materials. Furthermore, the issue of how to reduce a height of a shoulder peak in an emission spectrum to improve color purity of light emitted by molecules of a material is particularly important for blue and deep-blue light-emitting materials, as this significantly affects efficiency and energy utilization of top-emission devices in commercial applications. However, there are still some technical challenges in the development of the platinum complex materials and devices, and improving device efficiency and lifetime remains an important research topic. Therefore, novel phosphorescent platinum(II) complexes need to be developed. SUMMARY In view of the above, the present disclosure aims to provide a fused-ring carbazole tetradentate platinum(II) complex. When used as a light-emitting layer to fabricated an organic electroluminescent device, the fused-ring carbazole tetradentate platinum(II) complex in the