CN-117285558-B - Organic electroluminescent material containing boron nuclear receptor and application thereof in luminescent device

Abstract

An organic electroluminescent material containing boron nuclear receptor and application thereof in luminescent devices, belonging to the technical field of organic electroluminescent materials. When designing molecules, we choose to embed the elements such as heavy atoms sulfur, selenium and the like into the nitrogen-containing aromatic hydrocarbon skeleton, and utilize the heavy atom effect to accelerate the exciton reverse cross-over process. Meanwhile, due to the electron-deficient property of boron atoms, elements such as oxygen, sulfur and the like are bridged to form a boron-containing acceptor core with higher fluorescence quantum efficiency, and the boron-containing acceptor core is connected with a multi-resonance nitrogen-containing arene skeleton to prepare a luminescent material with the advantages of two TADF molecules, which is easy to synthesize and film, has the advantages of charge transfer characteristics of both multi-resonance type and donor-acceptor type molecules, and is used as a guest material for preparing a luminescent layer of an organic electroluminescent device, so that a device with high efficiency and low efficiency roll-off is obtained.

Inventors

• ZHANG ZUOLUN
• FAN XIANGYU

Assignees

• 吉林大学

Dates

Publication Date

20260512

Application Date

20230925

Claims (7)

1. 1. The organic electroluminescent material containing boron nuclear acceptor has the structure shown in one of the general formulas I, II and III: A. A 1 , which are identical or different, are independently selected from oxygen, sulfur, selenium or sulfonyl; X is independently selected from CR 1 2 , oxygen, sulfur, selenium, carbonyl, or sulfonyl; R, R 1 are each independently selected from substituted or unsubstituted C 1 ～C 10 alkyl, substituted or unsubstituted C 6 ～C 30 aryl, substituted or unsubstituted C 3 ～C 30 heteroaryl, and substituents are selected from C 1 ～C 10 alkyl, C 6 ～C 30 aryl, C 3 ～C 30 heteroaryl.
2. 2. An organic electroluminescent material comprising boron-containing core acceptor according to claim 1 wherein R is independently selected from C 1 ～C 4 alkyl, substituted or unsubstituted C 6 ～C 30 aryl, and R 1 is independently selected from C 1 ～C 4 alkyl, substituted or unsubstituted C 6 ～C 30 aryl.
3. 3. An organic electroluminescent material comprising boron-containing core acceptor according to claim 2 wherein R is independently selected from methyl, isopropyl, tert-butyl or phenyl, and R 1 is independently selected from methyl or m-xylene.
4. 4. The organic electroluminescent material as claimed in claim 3, wherein the organic electroluminescent material comprises a boron-containing core acceptor having a structural formula as shown in one of the following, Me, iPr, t-Bu, ph and MX respectively represent methyl, isopropyl, tertiary butyl, phenyl and m-dimethylphenyl.
5. 5. An organic electroluminescent device comprises an anode layer, a cathode layer and an organic functional layer arranged between the anode layer and the cathode layer, wherein the organic functional layer comprises a hole transmission area, a luminescent layer and an electron transmission area, and is characterized in that the luminescent layer contains the organic electroluminescent material containing the boron-containing nuclear receptor as claimed in any one of claims 1-4.
6. 6. An organic electroluminescent device as claimed in claim 5, wherein the organic electroluminescent material comprising a boron-containing core acceptor is used as a guest doping material in combination with other host materials.
7. 7. A display screen or a display panel, characterized in that the organic electroluminescent device as claimed in claim 6 is used in the display screen or the display panel.

Description

Organic electroluminescent material containing boron nuclear receptor and application thereof in luminescent device Technical Field The invention belongs to the technical field of organic electroluminescent materials, and particularly relates to an organic electroluminescent material containing a boron nuclear receptor and application thereof in a luminescent device. Background Organic Light Emitting Diodes (OLEDs) are a new generation of display device technology in the display field, and have been rapidly developed once they have been developed by virtue of their flexibility and flexibility, wide viewing angle, light emission, and rapid response speed. The organic electroluminescence technology can be mainly applied to illumination and display, commercial production of OLEDs is realized in display application in the display field, flagship products of various panel factories are formed, and light color adjustability can be realized to a large extent in the illumination field due to modification of the OLEDs by organic molecules, so that the organic electroluminescence technology represents a gradually brand-new angle of products in the market. The organic electroluminescent device includes a functional layer and a light emitting layer. The light-emitting layer is typically composed of a host material, which typically acts as a medium for energy transfer and to prevent the quenching of fluorescence aggregation due to excessive concentrations, and a guest material, which is typically doped in the host material as a carrier for photon radiation. From the utilization rate of excitons, the traditional fluorescent material can only utilize 25% of excitons, which greatly reduces the efficiency of the device, the second-generation phosphorescent material can utilize all excitons, but the luminescent material usually contains heavy metals such as platinum, iridium and the like, so that the cost is high, the commercial production is not favored, and the new-generation heat-activated delayed fluorescent material (TADF: THERMALLY ACTIVATED DELAYED Fluorescence) realizes triplet exciton luminescence through reverse gap crossing, and is usually composed of rich and cheap elements such as C, H, O, N and the like, and the cost is low. However, TADF-OLEDs generally require a compromise between the contradictory two aspects of small singlet energy level differences and large oscillator strength in molecular design. But also in terms of device performance, such as brightness, lifetime, etc., further optimization is required. Since the emergence of TADF materials with a B/N-strong polycyclic aromatic skeleton as a core structure, many researchers have attracted attention, the highest energy occupied orbital (h O m O) and the lowest energy unoccupied orbital (LUMO) are defined at adjacent positions and the fluorescence quantum efficiency (PLQY) is very high due to their multiple resonance properties, and the half-peak width is narrowed due to their strong rigid skeleton. In recent years, a strong rigid polycyclic aromatic skeleton with simple synthesis and high fluorescence quantum efficiency is presented, the compound realizes the property of multiple resonance by utilizing N, C atomic electronegativity difference, and then the nitrogen-containing aromatic hydrocarbon multiple resonance skeleton of indolocarbazoles is derived. However, TADF-OLEDs of multiple resonance nature typically have large singlet energy differences, and therefore the rate of reverse gap cross-over is low for most of these compounds. Classical acceptor-donating TADF molecules, however, may be helpful for reverse interstitial crossover rates if this feature can be applied in molecular design due to the small singlet energy level difference. Disclosure of Invention The invention combines two strong molecular rigidity multiple resonance mother cores to synthesize the novel organic electroluminescent material containing boron nuclear receptor. When designing molecules, we choose to embed the elements such as heavy atoms sulfur, selenium and the like into the nitrogen-containing aromatic hydrocarbon skeleton, and utilize the heavy atom effect to accelerate the exciton reverse cross-over process. Meanwhile, due to the electron-deficient property of boron atoms, the boron-containing acceptor core is widely applied to the fields of organic electroluminescent devices, organic solar cells and the like by a plurality of scientists, boron-containing acceptor cores with higher fluorescence quantum efficiency formed by bridging elements such as oxygen, sulfur and the like are used, the boron-containing acceptor cores are connected with multiple resonance nitrogenous aromatic hydrocarbon frameworks to prepare the luminescent material with the advantages of two types of TADF molecules, the luminescent material is easy to synthesize and film, the luminescent material has the advantages of charge transfer characteristics of both multiple resonance type molecules and don