WO2020211125A1 - Matériau à fluorescence retardée activé thermiquement, procédé de préparation correspondant et dispositif à diode électroluminescente organique - Google Patents

Matériau à fluorescence retardée activé thermiquement, procédé de préparation correspondant et dispositif à diode électroluminescente organique Download PDF

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WO2020211125A1
WO2020211125A1 PCT/CN2019/085638 CN2019085638W WO2020211125A1 WO 2020211125 A1 WO2020211125 A1 WO 2020211125A1 CN 2019085638 W CN2019085638 W CN 2019085638W WO 2020211125 A1 WO2020211125 A1 WO 2020211125A1
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activated delayed
compound
delayed fluorescent
layer
thermally activated
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PCT/CN2019/085638
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Chinese (zh)
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罗佳佳
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武汉华星光电半导体显示技术有限公司
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Publication of WO2020211125A1 publication Critical patent/WO2020211125A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D413/00—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and oxygen atoms as the only ring hetero atoms
    • C07D413/14—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and oxygen atoms as the only ring hetero atoms containing three or more hetero rings
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/06—Luminescent, e.g. electroluminescent, chemiluminescent materials containing organic luminescent materials
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/60—Organic compounds having low molecular weight
    • H10K85/649—Aromatic compounds comprising a hetero atom
    • H10K85/657—Polycyclic condensed heteroaromatic hydrocarbons
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2211/00—Chemical nature of organic luminescent or tenebrescent compounds
    • C09K2211/10—Non-macromolecular compounds
    • C09K2211/1018—Heterocyclic compounds
    • C09K2211/1025—Heterocyclic compounds characterised by ligands
    • C09K2211/1029—Heterocyclic compounds characterised by ligands containing one nitrogen atom as the heteroatom
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2211/00—Chemical nature of organic luminescent or tenebrescent compounds
    • C09K2211/10—Non-macromolecular compounds
    • C09K2211/1018—Heterocyclic compounds
    • C09K2211/1025—Heterocyclic compounds characterised by ligands
    • C09K2211/1029—Heterocyclic compounds characterised by ligands containing one nitrogen atom as the heteroatom
    • C09K2211/1033—Heterocyclic compounds characterised by ligands containing one nitrogen atom as the heteroatom with oxygen

Definitions

  • the invention belongs to the technical field of electroluminescent materials, and particularly relates to a thermally activated delayed fluorescent material, a preparation method thereof, and an organic electroluminescent diode device.
  • OLED display panels have active light emission without backlight, high luminous efficiency, large viewing angle, fast response speed, large temperature adaptation range, relatively simple production and processing technology, and drive
  • the advantages of low voltage, low energy consumption, lighter and thinner, flexible display and huge application prospects have attracted the attention of many researchers.
  • the principle of the OLED device is that under the action of an electric field, holes and electrons are injected from the anode and the cathode respectively, through the hole injection layer, the hole transport layer, the electron injection layer, and the electron transport layer, respectively, to form excitons in the light emitting layer.
  • Exciton radiation attenuates luminescence.
  • organic electroluminescent materials have a great impact on the performance of the devices.
  • the light-emitting layer of an OLED device generally contains a host material and a guest material, and the light-emitting guest material that plays a leading role is very important.
  • the light-emitting guest materials used in early OLED devices were fluorescent materials. Since the ratio of singlet and triplet excitons in OLED devices is 1:3, the theoretical internal quantum efficiency (IQE) of OLED devices based on fluorescent materials is only It can reach 25%, which greatly limits the application of fluorescent electroluminescent devices. Due to the spin-orbit coupling of heavy atoms, heavy metal complex phosphorescent materials can simultaneously use singlet and triplet excitons to achieve 100% IQE.
  • the pure organic thermally activated delayed fluorescence (TADF) material has a molecular structure combining electron donor (D) and electron acceptor (A).
  • D electron donor
  • A electron acceptor
  • the molecule has a small minimum single triplet energy difference ( ⁇ E) ST ), so that the triplet excitons can return to the singlet state through the reverse intersystem crossing (RISC), and then through the radiation transition to the ground state to emit light, so that the singlet and triplet excitons can be used at the same time, and 100% can also be achieved IQE.
  • TADF materials For TADF materials, fast reverse intersystem crossing constant (k RISC ) and high photoluminescence quantum yield (PLQY) are necessary conditions for the preparation of high-efficiency OLED devices. At present, TADF materials with the above conditions are still relatively scarce compared to heavy metal Ir complexes.
  • the purpose of the present invention is to provide a thermally activated delayed fluorescent material, which has an ultrafast reverse inter-system crossing rate and high luminous efficiency, is a blue-green TADF compound with significant TADF characteristics, and can be used as an organic electroluminescent diode Light-emitting layer material.
  • Another object of the present invention is to provide a method for preparing a thermally activated delayed fluorescent material, which is easy to operate and has a high yield of the target product.
  • Another object of the present invention is to provide an organic electroluminescent diode device, which uses the thermally activated delayed fluorescent material as the light-emitting layer material, thereby improving the light-emitting efficiency of the device.
  • the present invention provides a thermally activated delayed fluorescent material, which has a chemical structure shown in the following formula 1:
  • R represents a chemical group as an electron donor, R is in the 1, 3, 4 or 5 position in the pyridine group, X is One of them.
  • the chemical group R of the electron donor is selected from any one of the following groups:
  • the thermally activated delayed fluorescent material is compound 1, compound 2 or compound 3.
  • the structural formulas of compound 1, compound 2 and compound 3 are as follows:
  • the present invention also provides a preparation method of thermally activated delayed fluorescent material, and its chemical synthesis route is as follows:
  • the general structural formula of the halogenated raw material is Wherein, Br is at the 1, 3, 4 or 5 position in the pyridine group;
  • the general structural formula of the electron-donor-containing compound is R-H, where R represents a chemical group as an electron donor.
  • the chemical group R of the electron donor is selected from any one of the following groups:
  • the electron-donating compound is phenoxazine
  • the halogenated raw material is raw material 1, raw material 2 or raw material 3, and the structural formulas of raw material 1, raw material 2 and raw material 3 are respectively
  • the present invention also provides an organic electroluminescent diode device, including a substrate, a first electrode provided on the substrate, an organic functional layer provided on the first electrode, and a second electrode provided on the organic functional layer ;
  • the organic functional layer includes one or more organic film layers, and at least one of the organic film layers is a light-emitting layer;
  • the light-emitting layer includes the thermally activated delayed fluorescence compound as described above.
  • the light-emitting layer is formed by vacuum evaporation or solution coating.
  • the material of the light-emitting layer is a mixture of a host material and a guest material, and the guest material is selected from one or more of the thermally activated delayed fluorescence compounds described above.
  • the substrate is a glass substrate, the material of the first electrode is indium tin oxide, and the second electrode is a double-layer composite structure composed of a lithium fluoride layer and an aluminum layer;
  • the organic functional layer includes multiple organic film layers, the multilayer organic film layer includes a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer, wherein the material of the hole injection layer is molybdenum trioxide
  • the material of the hole transport layer is TCTA
  • the material of the electron transport layer is TmPyPB
  • the host material is mCBP.
  • the present invention has the following advantages and beneficial effects:
  • the present invention designs a thermally activated delayed fluorescent material with significant TADF characteristics by fine-tuning the structure and position of the electron donor group, and realizes the fine-tuning of the material's emission spectrum from blue to green light;
  • the thermally activated delayed fluorescent material of the present invention is a TADF compound with a lower single triplet energy level difference, an ultrafast reverse intersystem crossing rate and high luminous efficiency, when it is used as a luminescent material in an organic light-emitting display device At this time, the luminous efficiency of the organic light-emitting display device can be improved, and the organic electroluminescent diode devices based on the thermally activated delayed fluorescent material of the present invention have achieved very high device efficiency.
  • Figure 1 is a diagram of HOMO and LUMO energy levels of compounds 1-3 prepared in specific examples 1-3 of the present invention
  • Figure 2 is a photoluminescence spectrum of compound 1-3 prepared in specific examples 1-3 of the present invention in a toluene solution at room temperature;
  • Fig. 3 is a schematic diagram of the structure of the organic electroluminescent diode device of the present invention.
  • the synthetic route of target compound 1 is as follows:
  • the synthetic route of target compound 2 is as follows:
  • raw material 2 (2.09g, 5mmol), phenoxazine (2.2g, 12mmol), palladium acetate (90mg, 0.4mmol) and tri-tert-butylphosphine tetrafluoroborate (0.34g, 1.2 mmol), sodium tert-butoxide (1.16 g, 12 mmol) was added to the glove box, 60 mL of toluene that had been dewatered and deoxygenated was injected under an argon atmosphere, and reacted at 120° C. for 24 hours.
  • the synthetic route of target compound 3 is as follows:
  • raw material 3 (2.09g, 5mmol), phenoxazine (2.2g, 12mmol), palladium acetate (90mg, 0.4mmol) and tri-tert-butylphosphine tetrafluoroborate (0.34g, 1.2 mmol), sodium tert-butoxide (1.16 g, 12 mmol) was added to the glove box, 60 mL of toluene that had been dewatered and deoxygenated was injected under an argon atmosphere, and reacted at 120° C. for 24 hours.
  • Figure 1 shows the orbital arrangement of compound 1-3. It can be clearly seen from Figure 1 that the highest electron occupied orbital (HOMO) and lowest electron unoccupied orbital (LUMO) of compound 1-3 are arranged in In different units, complete separation is achieved, which helps to reduce the energy difference ⁇ EST between systems, thereby improving the ability of reverse intersystem crossing.
  • Figure 2 shows the photoluminescence spectra of Compound 1-3 in a toluene solution at room temperature. For compounds 1-3, the lowest singlet energy level S1 and the lowest triplet energy level T1 of the molecule were simulated and calculated.
  • Examples 1-3 The relevant data of Examples 1-3 are shown in Table 1. It can be seen from Table 1 that the ⁇ Est of all the compounds is less than 0.3ev, which achieves a small singlet and triplet energy level difference, and has an obvious delayed fluorescence effect.
  • PL Peak represents the photoluminescence peak
  • S1 represents the singlet energy level
  • T1 represents the triplet energy level
  • ⁇ EST represents the difference between the singlet and triplet energy levels.
  • OLED organic electroluminescent diode
  • the organic electroluminescent diode device using the thermally activated delayed fluorescent material of the present invention as the guest material of the light-emitting layer may include a substrate 9, an anode layer 1, a hole injection layer 2, and a cavity which are sequentially arranged from bottom to top.
  • the substrate 9 is a glass substrate
  • the material of the anode 1 is indium tin oxide (ITO)
  • the substrate 9 and the anode 1 together constitute ITO glass.
  • the material of the hole injection layer 2 is molybdenum trioxide (MoO 3 ), the material of the hole transport layer 3 is TCTA, and the material of the light-emitting layer is a mixture of the activated delayed fluorescent compound of the present invention and mCBP.
  • the material of the electron transport layer 5 is TmPyPB.
  • the cathode has a double-layer structure composed of a lithium fluoride (LiF) layer and an aluminum (Al) layer.
  • TCTA refers to 4,4',4”-tris(carbazol-9-yl)triphenylamine
  • mCBP refers to 3,3'-bis(N-carbazolyl)-1,1'-biphenyl
  • TmPyPB refers to 1,3,5-Tris(3-(3-pyridyl)phenyl)benzene.
  • the organic electroluminescent diode device can be manufactured according to a method known in the art, and the specific method is: sequentially vapor-depositing a 2nm thick MoO 3 film, a 35nm thick TCTA film, and a DPEPO on the cleaned ITO glass under high vacuum conditions. Add activated delayed fluorescent compound, 40nm thick Tm3PyPB film, 1nm thick LiF film and 100nm thick Al film.
  • the device as shown in Figure 3 is made by this method, and the specific device structures are as follows:
  • the current-brightness-voltage characteristics of devices 1-3 are completed by the Keithley source measurement system (Keithley 2400 Sourcemeter, Keithley 2000 Currentmeter) with a calibrated silicon photodiode, and the electroluminescence spectrum is performed by the French JY company SPEX CCD3000 spectrometer All measurements are done in room temperature atmosphere.
  • the performance data of devices 1-3 are shown in Table 2 below.
  • CIEy is the y coordinate value of the standard CIE color space.
  • the present invention studies the influence of the electron donor position on the material performance by adjusting the position of the electron donor with isomerism, and designs a thermally activated delayed fluorescent material with significant TADF characteristics to realize the material luminescence.
  • the spectrum is adjusted from blue-green light to green light; when the present invention further applies the thermally activated delayed fluorescent material to the guest material of an organic electroluminescent diode device, it can effectively improve the luminous efficiency of the organic electroluminescent diode device, based on
  • the organic electroluminescent diode device of the thermally activated delayed fluorescent material of the present invention has a very high device efficiency.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Electroluminescent Light Sources (AREA)

Abstract

La présente invention concerne un matériau à fluorescence retardée activé thermiquement, un procédé de préparation correspondant et un dispositif à diode électroluminescente organique. Le matériau à fluorescence retardée activé thermiquement a une formule générale structurale telle que représentée dans la formule I : R représente un groupe chimique en tant que donneur d'électrons, R est situé au niveau de la première position, de la troisième position, de la quatrième position ou de la cinquième position d'un groupe pyridyle, et X est l'une des formules. Le matériau à fluorescence retardée activé thermiquement selon la présente invention a un taux de croisement intersystème inverse ultra-rapide et un rendement lumineux élevé, est un matériau TADF à lumière bleue-verte ayant des caractéristiques TADF significatives, et peut améliorer de manière efficace l'efficacité lumineuse d'un dispositif à diode électroluminescente organique lorsqu'il est incorporé dans celui-ci en tant que matériau de couche luminescente, le dispositif à diode électroluminescente organique basé sur le matériau à fluorescence retardée activé thermiquement fourni par la présente invention présente ainsi une efficacité de dispositif très élevée.
PCT/CN2019/085638 2019-04-16 2019-05-06 Matériau à fluorescence retardée activé thermiquement, procédé de préparation correspondant et dispositif à diode électroluminescente organique WO2020211125A1 (fr)

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CN201910305986.6A CN110003194A (zh) 2019-04-16 2019-04-16 热活化延迟荧光材料及其制备方法与有机电致发光二极管器件
CN201910305986.6 2019-04-16

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CN110563633B (zh) * 2019-08-30 2022-11-08 武汉华星光电半导体显示技术有限公司 蓝光热活化延迟荧光材料及其制备方法、电致发光器件
CN113620973B (zh) * 2021-07-16 2024-05-07 西北工业大学 一种热活化延迟荧光材料及其制备方法和应用
CN114478487A (zh) * 2022-02-21 2022-05-13 上海天马微电子有限公司 一种有机化合物、有机发光显示面板及其应用
CN114702446A (zh) * 2022-05-11 2022-07-05 山西华辉光电科技有限公司 一种高效窄带深蓝光热活化型延迟荧光材料及制备与应用

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