A boron-containing organic compound and an organic electroluminescent device prepared therefrom

Abstract

The present invention discloses a boron-containing organic compound and an organic electroluminescent device prepared therefrom, belonging to the technical field of semiconductors. The structure of the organic compound of the present invention is shown in general formula (1). The compound of the present invention has a narrow full width at half maximum and can be used as a green light doping material for the light-emitting layer of an organic electroluminescent device, thereby improving the color purity and lifespan of the device.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a boron-containing organic compound as an OLED doping material and an organic electroluminescent device containing the same. Background Art

[0002] Traditional fluorescent doped materials are limited by early technologies and can only use 25% of singlet excitons formed by electrical excitation to emit light. The internal quantum efficiency of the device is low (up to 25%), and the external quantum efficiency is generally less than 5%, which is far behind the efficiency of phosphorescent devices. Since the strong spin-orbit coupling of the heavy atom center enhances intersystem crossing, phosphorescent materials can effectively use singlet and triplet excitons formed by electrical excitation to emit light, making the internal quantum efficiency of the device reach 100%. However, most phosphorescent materials are expensive, have poor material stability, poor color purity, and serious device efficiency roll-off, which limits their application in OLEDs.

[0003] With the advent of the 5G era, higher requirements are placed on color rendering standards. In addition to being efficient and stable, luminescent materials also require a narrower half-width to improve the purity of the device's luminescent color. Fluorescent doped materials can achieve high fluorescence quantum and narrow half-width through molecular engineering. Blue fluorescent doped materials have achieved a phased breakthrough, and the half-width of boron materials can be reduced to below 30nm. In the green light region, which is more sensitive to the human eye, research is mainly focused on phosphorescent doped materials, but their luminescent peak shape is difficult to narrow by simple methods. Therefore, in order to meet higher color rendering standards, it is of great significance to study efficient green fluorescent doped materials with narrow half-width.

[0004] In addition, the sensitization technology combines triplet exciton-sensitizing materials with fluorescent doping materials, uses triplet exciton-sensitizing materials as exciton-sensitizing media, makes full use of triplet excitons, and transfers energy to fluorescent doping materials through energy transfer, which can also achieve 100% device quantum efficiency. This technology can make up for the shortcomings of insufficient exciton utilization of fluorescent doping materials, and effectively give play to the characteristics of high fluorescence quantum yield, high device stability, high color purity and low price of fluorescent doping materials, and has broad prospects in OLEDs applications.

[0005] Boron-based compounds with resonance structures are more likely to achieve narrow full-width at half-maximum (FWHM) luminescence. When such materials are applied in sensitization technologies, devices with high efficiency and narrow FWHM emission can be fabricated. For example, in CN 107507921 A and CN 110492006 A, a luminescent layer combination technology is disclosed, which uses a thermally activated delayed fluorescence (TADF) material with a singlet-triplet energy gap less than or equal to 0.2 eV as the host and a boron-based material as the dopant; in CN 110492005 A and CN 110492009 A, a luminescent layer combination scheme is disclosed, which uses an exciplex as the host and a boron-based material as the dopant. Both can achieve efficiency comparable to phosphorescence and a relatively narrow FWHM. Therefore, developing sensitization technologies based on narrow FWHM boron-based luminescent materials has unique advantages and strong potential in meeting the BT.2020 display standards. Summary of the Invention

[0006] In view of the above problems existing in the prior art, the present invention provides a boron-containing organic compound and an organic electroluminescent device prepared therefrom. The compound of the present invention has a narrow FWHM and can be used as a green dopant material for the luminescent layer of an organic electroluminescent device, thereby improving the color purity and lifespan of the device.

[0007] The technical solution of the present invention is as follows: A boron-containing organic compound, the structure of the boron-containing organic compound is shown in the general formula (1):

[0008]

[0009] In the general formula (1), the M ring represents any one of the following structures:

[0010]

[0011] X1, X2, and X3 each independently represent O, S, N(R4), C(R5)(R6), or Si(R7)(R8);

[0012] Ar2 represents one of a substituted or unsubstituted phenyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted carbazolyl group;

[0013] The M ring can also form a ring with Ar2;

[0014] Z each occurrence, the same or different, represents C-R1;

[0015] Z1 each occurrence, the same or different, represents C-R2;

[0016] Z2 each occurrence, the same or different, represents C-R3;

[0017] There may also be a single-bond connection between Z1 and Z2;

[0018] Each occurrence of R1, R2, and R3, which may be the same or different, represents a hydrogen atom, a deuterium atom, a tritium atom, a halogen atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C1-C 10 alkoxy group, a substituted or unsubstituted C6-C 10 aryloxy group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group, and adjacent R1s may also be connected to each other to form a ring;

[0019] Ar1 represents a hydrogen atom, a deuterium atom, a tritium atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group;

[0020] R4, R5, R6, R7, and R8 represent a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group;

[0021] The substituents for the substituent groups are each independently selected from a deuterium atom, a halogen atom, a cyano group, a C1-C 10 alkyl group, a C3-C 10 cycloalkyl group, a C6-C 30 aryl group, a C2-C 30 heteroaryl group, an amino group, or one or more of them;

[0022] The heteroatoms in the heteroaryl groups are each independently selected from one or more of oxygen, sulfur, nitrogen, and silicon atoms.

[0023] In a preferred embodiment, the structure of the organic compound is any one of general formula (2) and general formula (3):

[0024]

[0025] In general formula (2) and general formula (3), the meanings of X1, Ar1, Ar2, Z, Z1, and Z2 are the same as those defined above.

[0026] Preferred embodiment, the structure of the organic compound is any one of general formula (4) and general formula (5):

[0027]

[0028] In general formula (4) and general formula (5), the meanings of X1, Ar1, Ar2, Z, Z1, and Z2 are the same as the definitions in the above text.

[0029] Preferred embodiment, the structure of the organic compound is any one of general formula (II-1) to general formula (II-9):

[0030]

[0031] In general formula (II-1) to general formula (II-9), the meanings of Ar1, Ar2, Z, Z1, and Z2 are the same as the definitions in the above text.

[0032] Preferred embodiment, the structure of the organic compound is any one of general formula (Ⅲ-1) to general formula (Ⅲ-5):

[0033]

[0034] In general formula (Ⅲ-1) to general formula (Ⅲ-5), the meanings of X1, Ar1, and Z are the same as the definitions in the above text;

[0035] R a 、R c 、R d 、R e Each occurrence, the same or different, represents a hydrogen atom, a deuterium atom, a tritium atom, a halogen atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C1-C 10 alkoxy group, a substituted or unsubstituted C6-C 10 aryloxy group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group, and adjacent Rs can also be connected to each other to form a ring;

[0036] R b represents a deuterium atom, a halogen atom, a cyano group, a C1-C 10 alkyl group, a C3-C 10 cycloalkyl group, a C6-C 30 aryl group, a C2-C 30 heteroaryl group, an amino group;

[0037] The substituents for the substituents are each independently selected from a deuterium atom, a halogen atom, a cyano group, a C1-C 10alkyl groups having from C3 to C 10 cycloalkyl groups having from C6 to C 30 aryl groups, C2-C 30 heteroaryl groups, amino groups, or one or more of them;

[0038] The heteroatoms in the heteroaryl groups are each independently selected from one or more of oxygen, sulfur, nitrogen, and silicon atoms.

[0039] In a preferred embodiment, R1, R2, R3, Ar1, R a R b R c R d R e are each independently a hydrogen atom, a deuterium atom, a tritium atom, a halogen atom, an adamantyl group, a methyl group, a deuterated methyl group, a tritiated methyl group, a trifluoromethyl group, an ethyl group, a deuterated ethyl group, a tritiated ethyl group, an isopropyl group, a deuterated isopropyl group, a tritiated isopropyl group, a tert-butyl group, a deuterated tert-butyl group, a tritiated tert-butyl group, a cyclopentyl group, a deuterated cyclopentyl group, a tritiated cyclopentyl group, a methyl-substituted cyclopentyl group, a cyclohexyl group, a phenyl group, a deuterated phenyl group, a tritiated phenyl group, a biphenyl group, a deuterated biphenyl group, a tritiated biphenyl group, a terphenyl group, a deuterated terphenyl group, a tritiated terphenyl group, a diphenyl ether group, a methyl-substituted diphenyl ether group, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a pyridyl group, a phenyl-substituted pyridyl group, a quinolinyl group, a furyl group, a thienyl group, a benzofuryl group, a dibenzofuryl group, a dibenzothienyl group, a carbazolyl group, an N-phenylcarbazolyl group, a 9,9-dimethylfluorenyl group, a spirofluorene group, a methyl-substituted phenyl group, an ethyl-substituted phenyl group, an isopropyl-substituted phenyl group, a tert-butyl-substituted phenyl group, a methyl-substituted biphenyl group, an ethyl-substituted biphenyl group, an isopropyl-substituted biphenyl group, a tert-butyl-substituted biphenyl group, a deuterated methyl-substituted phenyl group, a deuterated ethyl-substituted phenyl group, a deuterated isopropyl-substituted phenyl group, a deuterated tert-butyl-substituted phenyl group, a deuterated methyl-substituted biphenyl group, a deuterated ethyl-substituted biphenyl group, a deuterated isopropyl-substituted biphenyl group, a deuterated tert-butyl-substituted biphenyl group, a phenyl-substituted amino group, a tert-butylbenzene-substituted amino group, a tert-butyl-substituted dibenzofuryl group, a phenyl-substituted tert-butyl group, an xanthone group, a phenyl-substituted triazine group, a phenyl-substituted boranyl group, a methoxy group, a tert-butoxy group;

[0040] R4, R5, R6, R7, and R8 represent one of the following: adamantyl, methyl, deuterated methyl, tritiated methyl, trifluoromethyl, ethyl, deuterated ethyl, tritiated ethyl, isopropyl, deuterated isopropyl, tritiated isopropyl, tert-butyl, deuterated tert-butyl, tritiated tert-butyl, cyclopentyl, deuterated cyclopentyl, tritiated cyclopentyl, methyl-substituted cyclopentyl, cyclohexyl, phenyl, deuterated phenyl, tritiated phenyl, biphenyl, deuterated biphenyl, tritiated biphenyl, terphenyl, deuterated terphenyl, tritiated terphenyl, diphenyl ether group, methyl-substituted diphenyl ether group, naphthyl, anthracenyl, phenanthryl, pyrenyl, pyridyl, phenyl-substituted pyridyl, quinolinyl, furyl, thienyl, benzofuranyl, dibenzofuranyl, dibenzothienyl, carbazolyl, N-phenylcarbazolyl, 9,9-dimethylfluorenyl, spirofluorene, methyl-substituted phenyl, ethyl-substituted phenyl, isopropyl-substituted phenyl, tert-butyl-substituted phenyl, methyl-substituted biphenyl, ethyl-substituted biphenyl, isopropyl-substituted biphenyl, tert-butyl-substituted biphenyl, deuterated methyl-substituted phenyl, deuterated ethyl-substituted phenyl, deuterated isopropyl-substituted phenyl, deuterated tert-butyl-substituted phenyl, deuterated methyl-substituted biphenyl, deuterated ethyl-substituted biphenyl, deuterated isopropyl-substituted biphenyl, deuterated tert-butyl-substituted biphenyl, tert-butyl-substituted dibenzofuranyl, phenyl-substituted tert-butyl, xanthone group, phenyl-substituted triazine group;

[0041] The substituents for the substitution groups are each independently selected from one or more of the following: deuterium atom, fluorine atom, cyano group, methyl, tert-butyl, isopropyl, phenyl, naphthyl, pyridyl.

[0042] Preferably, R1, R2, R3, Ar1, Ra, R b , R c , R d , R e are represented by the following structures:

[0043]

[0044]

[0045] Preferably, the specific structural formula of the organic compound is any one of the following structures:

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056] An organic electroluminescent device includes a cathode and an anode, and an organic light-emitting functional layer therebetween. The organic light-emitting functional layer includes a light-emitting layer, and the light-emitting layer contains the boron-containing organic compound.

[0057] In a preferred embodiment, the light-emitting layer contains a host material and a doping material, and the doping material contains the boron-containing organic compound.

[0058] In a preferred embodiment, the light-emitting layer contains a first host material, a second host material and a doping material. At least one of the first host material and the second host material is a TADF material, and the doping material contains the boron-containing organic compound.

[0059] In a preferred embodiment, the light-emitting layer contains a host material, an exciton sensitizing material and a doping material. The exciton sensitizing material is a metal element-containing complex, and the doping material contains the boron-containing organic compound.

[0060] The beneficial technical effects of the present invention are as follows:

[0061] (1) The compound of the present invention can be used as a doping material for the light-emitting layer material in an OLED device, and can emit green fluorescence under the action of an electric field, and can be applied to the fields of OLED lighting or OLED display;

[0062] (2) The compound of the present invention is used as a doping material, and a phosphorescent material is introduced as an exciton sensitizer, which can effectively improve the device life;

[0063] (3) The spectral FWHM of the compound of the present invention is narrow, which can effectively improve the device color gamut and the device luminous efficiency. Description of the Drawings

[0064] Figure 1 It is a schematic structural diagram of the materials listed in the present invention applied to an OLED device;

[0065] Among them, 1 is a transparent substrate layer, 2 is an anode layer, 3 is a hole injection layer, 4 is a hole transport layer, 5 is an electron blocking layer, 6 is a light-emitting layer, 7 is a hole blocking layer, 8 is an electron transport layer, 9 is an electron injection layer, and 10 is a cathode layer. Specific embodiments

[0066] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will be further described below in conjunction with the drawings and specific embodiments, but it is not intended to limit the present invention.

[0067] In the present invention, when describing electrodes, organic electroluminescent devices, and other structures, terms indicating directions such as "upper", "lower", "top", and "bottom" only represent the directions in a specific state, and do not mean that the relevant structures can only exist in the described directions; on the contrary, if the structure can be transformed in position, for example, inverted, the direction of the structure will be changed accordingly. Specifically, in the present invention, the "bottom" and "lower" sides of the electrode refer to the side of the electrode close to the substrate during the preparation process, and the opposite side away from the substrate is the "top" and "upper" sides.

[0068] In the present invention, substituted or unsubstituted C6-C 30 aryl and / or substituted or unsubstituted C2-C 30 heteroaryl refers to substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthracenyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted condensed tetraphenyl, substituted or unsubstituted pyrenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted p-terphenyl, substituted or unsubstituted m-terphenyl, substituted or unsubstituted A base, a substituted or unsubstituted diaminotriphenyl group, a substituted or unsubstituted perylene group, a substituted or unsubstituted indene group, a substituted or unsubstituted furyl group, a substituted or unsubstituted thienyl group, a substituted or unsubstituted pyrrolyl group, a substituted or unsubstituted pyrazolyl group, a substituted or unsubstituted imidazolyl group, a substituted or unsubstituted triazolyl group, a substituted or unsubstituted oxazolyl group, a substituted or unsubstituted thiazolyl group, a substituted or unsubstituted oxadiazolyl group, a substituted or unsubstituted thiadiazolyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted pyrimidinyl group, a substituted or unsubstituted pyrazinyl group, a substituted or unsubstituted triazinyl group, a substituted or unsubstituted benzofuryl group, a substituted or unsubstituted benzothienyl group, a substituted or unsubstituted benzimidazolyl group, a substituted or unsubstituted indolyl group, a substituted or unsubstituted quinolinyl group, a substituted or unsubstituted isoquinolinyl group, a substituted or unsubstituted quinazolinyl group, a substituted or unsubstituted quinoxalinyl group, a substituted or unsubstituted naphthyridinyl group, a substituted or unsubstituted benzoxazinyl group, a substituted or unsubstituted benzothiazinyl group, a substituted or unsubstituted acridinyl group, a substituted or unsubstituted phenazinyl group, a substituted or unsubstituted phenothiazinyl group, a substituted or unsubstituted phenoxazinyl group, a substituted or unsubstituted fluorene group, a substituted or unsubstituted dibenzofuryl group, a substituted or unsubstituted dibenzothienyl group, a substituted or unsubstituted carbazolyl group, a combination thereof or a fused ring of a combination of the foregoing groups, but not limited thereto.

[0069] The C1-C 10 The alkyl group (including a straight-chain alkyl group and a branched-chain alkyl group) refers to a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, an isobutyl group, a sec-butyl group, a neopentyl group, a n-pentyl group, an isopentyl group, an octyl group, a heptyl group, a n-decyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 1-butylpentyl group, etc., but not limited thereto.

[0070] The halogen atom described in the present invention refers to a chlorine atom, a fluorine atom, a bromine atom, etc., but not limited thereto.

[0071] The C3-C 10 The cycloalkyl group refers to a monovalent monocyclic saturated hydrocarbon group including 3 to 10 carbon atoms as ring-forming atoms. In the present text, a C4-C9 cycloalkyl group is preferably used, a C5-C8 cycloalkyl group is more preferably used, and a C5-C7 cycloalkyl group is particularly preferably used. Non-limiting examples thereof may include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a 4-methylcyclohexyl group, a 4,4-dimethylcyclohexyl group, an adamantyl group, a cycloheptyl group, etc., but not limited thereto.

[0072] As the substrate of the organic electroluminescent device of the present invention, any substrate commonly used in organic electroluminescent devices can be used. Examples are transparent substrates such as glass or transparent plastic substrates; opaque substrates such as silicon substrates. Different substrates have different mechanical strengths, thermal stabilities, transparencies, surface smoothness, and water resistances. Depending on the nature of the substrate, its usage directions are different. In the present invention, a transparent PI film substrate is preferably used. The thickness of the substrate is not particularly limited.

[0073] A first electrode is formed on the substrate, and the first electrode and the second electrode can face each other. The first electrode can be an anode. The first electrode can be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the first electrode is a transmissive electrode, it can be formed using a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO), etc. When the first electrode is a semi-transmissive electrode or a reflective electrode, it can include Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a metal mixture. The thickness of the first electrode layer depends on the material used and is generally 50 - 500 nm, preferably 70 - 300 nm, and more preferably 100 - 200 nm.

[0074] The organic functional material layer disposed between the first electrode and the second electrode sequentially includes a hole transport region, a light-emitting layer, and an electron transport region from bottom to top.

[0075] In this context, examples of the hole transport region constituting the organic electroluminescent device can include a hole injection layer, a hole transport layer, an electron blocking layer, etc.

[0076] As the materials for the hole injection layer, the hole transport layer, and the electron blocking layer, any material can be selected from known related materials for OLED devices for use.

[0077] Examples of the above materials may be phthalocyanine derivatives, triazole derivatives, triarylmethane derivatives, triarylamine derivatives, oxazole derivatives, oxadiazole derivatives, hydrazone derivatives, stilbene derivatives, pyridinoline derivatives, polysilane derivatives, imidazole derivatives, phenylenediamine derivatives, amino-substituted quinolone derivatives, styryl anthracene derivatives, styrylamine derivatives and other styrene compounds, fluorene derivatives, spirofluorene derivatives, silazane derivatives, aniline copolymers, porphyrin compounds, carbazole derivatives, polyarylalkane derivatives, polyphenylene vinylene and its derivatives, polythiophene and its derivatives, poly-N-vinylcarbazole derivatives, thiophene oligomers and other conductive polymer oligomers, aromatic tertiary amine compounds, styrylamine compounds, triamines, tetraamines, benzidine compounds, propynediamine derivatives, p-phenylenediamine derivatives, m-phenylenediamine derivatives, 1,1'-bis(4-diarylaminophenyl)cyclohexane, 4,4'-bis(diarylamino)biphenyls, bis[4-(diarylamino)phenyl]methanes, 4,4'-bis(diarylamino)terphenyls, 4,4'-bis(diarylamino)quaterphenyls, 4,4'-bis(diarylamino)diphenyl ethers, 4,4'-bis(diarylamino)diphenyl sulfides, bis[4-(diarylamino)phenyl]dimethylmethanes, bis[4-(diarylamino)phenyl]-bis(trifluoromethyl)methanes or 2,2-diphenylethylene compounds, etc.

[0078] Furthermore, according to the device matching requirements, the hole transport film layer between the electron blocking layer and the hole injection layer that constitutes the organic electroluminescent device can be a single film layer or a stacked structure of multiple hole transport materials. In this article, for the above-mentioned hole carrier conduction film layers with different functions, their film thicknesses are not particularly limited.

[0079] The hole injection layer contains a host organic material that can conduct holes, and also contains a P-type doping material with a deep HOMO energy level (the corresponding LUMO energy level will also be very deep). Based on empirical summaries, in order to achieve smooth injection of holes from the anode to the organic film layer, the HOMO energy level of the host organic material that conducts holes used in the anode interface buffer layer must have certain characteristics with the P-doping material, so as to expect the occurrence of a charge transfer state between the host material and the doping material, achieve Ohmic contact between the buffer layer and the anode, and achieve efficient injection from the electrode to hole injection conduction.

[0080] In view of the above empirical summaries, for hole-type host materials with different HOMO energy levels, different P-doping materials need to be selected to match them in order to achieve Ohmic contact at the interface and improve the hole injection effect.

[0081] Therefore, in one embodiment of the present invention, in order to better inject holes, the hole injection layer further comprises a P-type doping material with charge conductivity selected from the following: quinone derivatives such as tetracyanoquinodimethane (TCNQ) and 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinodimethane (F4-TCNQ); or hexaazatriphenylene derivatives such as 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (HAT-CN); or cyclopropane derivatives such as 4,4',4”-((1E,1'E,1”E)-cyclopropane-1,2,3-trimethylenetris(cyanomethanylidene))tris(2,3,5,6-tetrafluorobenzyl); or metal oxides such as tungsten oxide and molybdenum oxide, but not limited thereto.

[0082] In the hole injection layer of the present invention, the ratio of the hole transport material to the P-type doping material used is 99:1 - 95:5, preferably 99:1 - 97:3, by mass.

[0083] The thickness of the hole injection layer of the present invention can be 5 - 100 nm, preferably 5 - 50 nm, and more preferably 5 - 20 nm, but the thickness is not limited to this range.

[0084] The thickness of the hole transport layer of the present invention can be 5 - 200 nm, preferably 10 - 150 nm, and more preferably 20 - 100 nm, but the thickness is not limited to this range.

[0085] The thickness of the electron blocking layer of the present invention can be 1 - 50 nm, preferably 5 - 40 nm, but the thickness is not limited to this range.

[0086] After forming the hole injection layer, the hole transport layer, and the electron blocking layer, a corresponding light-emitting layer is formed on the electron blocking layer.

[0087] The light-emitting layer may comprise a host material and a doping material. The host material can be a common green host material in the art, and the doping material is a boron-containing organic compound represented by the general formula (1) of the present invention.

[0088] The light-emitting layer may comprise a single host material or a dual host material;

[0089] The dual host material comprises a first host material and a second host material. At least one of the first host material and the second host material is preferably a TADF material;

[0090] TADF materials refer to materials with thermally activated delayed fluorescence properties, characterized by a small energy difference between the first singlet excited state and the first triplet excited state. Therefore, singlet excitons and triplet excitons generated can be utilized simultaneously in the device, enabling the exciton utilization rate generated electrochemically inside the device to approach 100% as much as possible. Compared with traditional fluorescent materials, TADF materials have a higher exciton utilization rate.

[0091] The light-emitting layer may comprise a host material, an exciton sensitizing material, and a doping material;

[0092] An exciton sensitizing material refers to a material that can enable the luminescent material in the light-emitting layer to fully utilize electrochemically generated excitons, thereby enabling the light-emitting layer to finally generate the emission spectrum of the sensitized material. The exciton sensitizer may undertake functions such as exciton capture, exciton conversion, and exciton transfer in the electroluminescent device. The boron-containing organic compound represented by the general formula (1) of the present invention and the exciton sensitizing material are used in combination, which has an obvious improvement effect on problems such as device efficiency improvement, exciton annihilation in the device, and efficiency reduction.

[0093] In the light-emitting layer of the present invention, the ratio of the host material to the doping material used is 99:1 - 70:30, preferably 99:1 - 85:15, and more preferably 97:3 - 87:13, based on mass.

[0094] The thickness of the light-emitting layer can be adjusted to optimize the luminescence efficiency and driving voltage. The preferred thickness range is 5 nm to 50 nm, further preferably 10 - 50 nm, and more preferably 15 - 40 nm, but the thickness is not limited to this range.

[0095] In the present invention, the electron transport region may sequentially include, from bottom to top, a hole blocking layer, an electron transport layer, and an electron injection layer provided above the light-emitting layer, but is not limited thereto.

[0096] The hole blocking layer is a layer that blocks holes injected from the anode from passing through the light-emitting layer and entering the cathode, thereby prolonging the lifespan of the device and improving the performance of the device. The hole blocking layer of the present invention may be provided above the light-emitting layer. As the hole blocking layer material of the organic electroluminescent device of the present invention, compounds known in the prior art with hole blocking effects can be used, such as phenanthroline derivatives such as bathocuproine (referred to as BCP), metal complexes of hydroxyquinoline derivatives such as aluminum(III) bis(2-methyl-8-quinolinolato)-4-phenylphenolate (BAlq), various rare earth complexes, oxazole derivatives, triazole derivatives, triazine derivatives, pyrimidine derivatives such as 9,9'-(5-(6-([1,1'-biphenyl]-4-yl)-2-phenylpyrimidin-4-yl)-1,3-phenylene)bis(9H-carbazole), etc. The thickness of the hole blocking layer of the present invention may be 2 - 200 nm, preferably 5 - 150 nm, but the thickness is not limited to this range.

[0097] The electron transport layer can be disposed above the light-emitting layer or (if present) the hole blocking layer. The electron transport layer material is a material that can easily receive electrons from the cathode and transfer the received electrons to the light-emitting layer. Materials with high electron mobility are preferred. As the electron transport layer of the organic electroluminescent device of the present invention, electron transport layer materials known in the prior art for organic electroluminescent devices can be used. For example, metal complexes of hydroxyquinoline derivatives represented by Alq3, BAlq, and Liq, various rare earth metal complexes, triazole derivatives, 2,4-bis(9,9-dimethyl-9H-fluoren-2-yl)-6-(naphthalen-2-yl)-1,3,5-triazine (CAS No.: 1459162-51-6) and other triazine derivatives, 2-(4-(9,10-bis(naphthalen-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole (CAS No.: 561064-11-7, commonly known as LG201) and other imidazole derivatives, oxadiazole derivatives, thiadiazole derivatives, carbodiimide derivatives, quinoxaline derivatives, phenanthroline derivatives, silicon-based compound derivatives, etc. The thickness of the electron transport layer of the present invention can be 10-80 nm, preferably 20-60 nm, and more preferably 25-45 nm, but the thickness is not limited to this range.

[0098] The electron injection layer can be disposed above the electron transport layer. The electron injection layer material is generally preferably a material with a low work function, so that electrons can be easily injected into the organic functional material layer. As the electron injection layer material of the organic electroluminescent device of the present invention, electron injection layer materials known in the prior art for organic electroluminescent devices can be used. For example, lithium; lithium salts such as lithium 8-hydroxyquinoline, lithium fluoride, lithium carbonate, or lithium azide; or cesium salts, cesium fluoride, cesium carbonate, or cesium azide. The thickness of the electron injection layer of the present invention can be 0.1-5 nm, preferably 0.5-3 nm, and more preferably 0.8-1.5 nm, but the thickness is not limited to this range.

[0099] The second electrode can be disposed above the electron transport region. The second electrode can be a cathode. The second electrode can be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the second electrode is a transmissive electrode, the second electrode can include, for example, Li, Yb, Ca, LiF / Ca, LiF / Al, Al, Mg, BaF, Ba, Ag, or a compound or mixture thereof; when the second electrode is a semi-transmissive electrode or a reflective electrode, the second electrode can include Ag, Mg, Yb, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof, but is not limited thereto. The thickness of the cathode depends on the material used.

[0100] The organic electroluminescent device of the present invention may further include a packaging structure. The packaging structure may be a protective structure for preventing external substances such as moisture and oxygen from entering the organic layer of the organic electroluminescent device. The packaging structure may be, for example, a can, such as a glass can or a metal can; or a thin film covering the entire surface of the organic layer.

[0101] A method for preparing the organic electroluminescent device of the present invention includes successively laminating an anode, a hole injection layer, a hole transport layer, an electron blocking layer, an organic film layer, an electron transport layer, an electron injection layer, and a cathode, and optionally a covering layer on a substrate. In this regard, methods such as vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing, or LITI can be used, but are not limited thereto. In the present invention, vacuum evaporation is preferably used to form each of the layers. Those skilled in the art can conventionally select each process condition in the vacuum evaporation method according to actual needs.

[0102] The raw materials involved in the synthesis examples of the present invention can all be purchased from the market or prepared by conventional preparation methods in the art;

[0103] Synthesis of Compound 6 in Example 1:

[0104]

[0105] Under nitrogen protection, 10 mmol of raw material A-1, 10 mmol of raw material B-1, 15 mmol of potassium carbonate, 0.5 mmol of copper, 15 mmol of 18-crown-6, and 70 mL of dichlorobenzene were added to a three-necked flask, and the mixture was refluxed for 18 hours. After the reaction was completed, the organic layer was concentrated under reduced pressure and then purified by silica gel column chromatography to obtain intermediate a-1. LC-MS: Measured value: 492.41 ([M+H] + )), theoretical value: 491.13.

[0106] Under nitrogen protection, 10 mmol of raw material C-1, 10 mmol of NaH, and 10 mL of anhydrous DMF were added to a three-necked flask, and the mixture was stirred at room temperature for 0.5 hour. Then, 10 mmol of raw material D-1 was added, and the reaction was carried out at room temperature for 5 hours. After the reaction was completed, 50 ml of deionized water was added, and the white precipitate was filtered. The precipitate was dissolved in dichloromethane, dried over anhydrous sodium sulfate, filtered, and concentrated. Column chromatography was used for separation to obtain intermediate b-1. LC-MS: Measured value: 394.05 ([M+H] + )), theoretical value: 393.19.

[0107] Under nitrogen protection, 10 mmol of intermediate a-1, 11 mmol of intermediate b-1, 1 mmol of X-phos, 20 mmol of Cs2CO3 and a mixed solution of toluene / EtOH / H2O (80 ml / 40 ml / 40 ml) were added to a three-necked flask, and then 0.5 mmol of Pd(OAc)2 was added. The reaction was stirred at 110 °C for 12 hours. After the reaction was completed, it was extracted with dichloromethane, and then the organic phase was dried with anhydrous magnesium sulfate. The solvent was removed and purified by silica gel column chromatography to obtain intermediate c-1. LC-MS: Measured value: 761.42 ([M+H] + ), theoretical value: 760.39.

[0108] In a three-necked flask, under nitrogen protection, 2.20 mmol of boron tribromide and 1.10 mmol of intermediate c-1 were dissolved in 30 mL of 1,2,4-trichlorobenzene. After stirring at 180 °C for 20 hours, the reaction mixture was diluted with dichloromethane (50 mL), and 100 mL of sodium phosphate buffer solution with pH = 6 was added at 0 °C. The aqueous layer was separated and extracted with dichloromethane (100 mL, three times). The crude product was purified by silica gel column chromatography to obtain the target compound 6. 1 1H NMR (400 MHz, Chloroform-d) δ 7.95–7.87 (m, 2H), 7.83–7.77 (m, 1H), 7.70–7.58 (m, 2H), 7.53–7.47 (m, 2H), 7.45–7.36 (m, 4H), 7.30–7.26 (m, 4H), 7.18–7.07 (m, 5H), 7.01–6.98 (m, 2H), 1.85–1.41 (s, 9H), 1.33–1.28 (d, 18H). FWHM (measured by Horiba's Fluorolog-3 series fluorescence spectrometer in the thin film state): 29 nm.

[0109] Synthesis of Compound 25 in Example 2:

[0110]

[0111] The preparation method of intermediate b-2 is the same as that of intermediate b-1, except that raw material D-2 is used to replace raw material D-1 to obtain intermediate b-2. LC-MS: Measured value: 472.39 ([M+H]+), theoretical value: 471.10.

[0112] Add 10 mmol of intermediate b-2, 1 mmol of tetrabutylammonium bromide (nBu4NBr), 0.5 mmol of triphenylphosphine, 0.2 mmol of palladium acetate catalyst, 20 mmol of potassium carbonate and 50 mL of DMAc to a two-necked flask in sequence. Then, under nitrogen protection, heat under reflux and stir for 12 hours. After cooling, separate the liquid by liquid separation and collect the organic phase. Dry the organic phase with anhydrous sodium sulfate, then filter and concentrate the organic phase. Separate the compound by silica gel column with petroleum ether:ethyl acetate = 100:1 as the eluent to obtain intermediate d-2. LC-MS: Measured value: 392.12 ([M+H] + ), theoretical value: 391.17.

[0113] The preparation method of intermediate c-2 is the same as that of intermediate c-1, except that intermediate d-2 is used to replace intermediate b-1 to obtain intermediate c-2. LC-MS: Measured value: 759.41 ([M+H] + ), theoretical value: 758.37.

[0114] The preparation method of compound 25 is the same as that of compound 6, except that intermediate c-2 is used to replace intermediate c-1 to obtain compound 25. 1 H NMR (400 MHz, Chloroform-d) δ 8.36 (m, 1H), 7.99–7.88 (m, 2H), 7.82–7.78 (m, 1H), 7.65–7.37 (m, 7H), 7.31–7.08 (m, 7H), 7.05–6.99 (m, 2H), 1.54–1.42 (d, 18H), 1.36–1.24 (s, 9H). FWHM (measured by Horiba's Fluorolog-3 series fluorescence spectrometer in the thin film state): 28 nm.

[0115] Synthesis of compound 29 in Example 3:

[0116]

[0117] The preparation method of intermediate a-3 is the same as that of intermediate a-1, except that raw material B-3 is used to replace raw material B-1 to obtain intermediate a-3. LC-MS: Measured value: 568.29 ([M+H] + ), theoretical value: 567.16.

[0118] The preparation method of intermediate b-3 is the same as that of intermediate b-1, except that raw material C-3 is used to replace raw material C-1 and raw material D-2 is used to replace raw material D-1 to obtain intermediate b-3. LC-MS: Measured value: 472.02 ([M+H] + ), theoretical value: 471.10.

[0119] The preparation method of intermediate d-3 is the same as that of intermediate d-2, except that intermediate b-3 is used to replace intermediate b-2 to obtain intermediate d-3. LC-MS: Measured value: 392.35([M+H] + ), theoretical value: 391.17.

[0120] The preparation method of intermediate c-3 is the same as that of intermediate c-1, except that intermediate a-3 is used to replace intermediate a-1 and intermediate d-3 is used to replace intermediate b-1 to obtain intermediate c-3. LC-MS: Measured value: 835.46([M+H] + ), theoretical value: 834.40.

[0121] The preparation method of compound 29 is the same as that of compound 6, except that intermediate c-3 is used to replace intermediate c-1 to obtain compound 29. 1 H NMR(400MHz,Chloroform-d)δ8.39–8.31(m,2H),7.98–7.92(m,1H),7.83–7.77(m,1H),7.60–7.15(m,16H),7.12–6.98(m,4H),1.50–1.44(d,18H),1.35–1.27(s,9H). FWHM (measured by Fluorolog-3 series fluorescence spectrometer of Horiba in the thin film state): 30nm.

[0122] Synthesis of compound 36 in Example 4:

[0123]

[0124] The preparation method of intermediate a-4 is the same as that of intermediate a-1, except that raw material A-4 is used to replace raw material A-1 to obtain intermediate a-4. LC-MS: Measured value: 492.30([M+H] + ), theoretical value: 491.13.

[0125] The preparation method of intermediate c-4 is the same as that of intermediate c-1, except that intermediate a-4 is used to replace intermediate a-1 to obtain intermediate c-4. LC-MS: Measured value: 761.52([M+H] + ), theoretical value: 760.39.

[0126] The preparation method of compound 36 is the same as that of compound 6, except that intermediate c-4 is used to replace intermediate c-1 to obtain compound 36. 11H NMR (400 MHz, Chloroform-d) δ 7.99–7.89 (m, 2H), 7.81–7.76 (m, 1H), 7.54–7.40 (m, 8H), 7.37–7.24 (m, 4H), 7.18–7.06 (m, 5H), 6.99–6.91 (m, 2H), 3.01–1.48 (s, 9H), 1.40–1.30 (d, 18H). FWHM (measured by Horiba's Fluorolog-3 series fluorescence spectrometer in the thin film state): 27 nm.

[0127] Synthesis of Compound 46 in Example 5:

[0128]

[0129] The preparation method of intermediate a-5 is the same as that of intermediate a-1, except that raw material A-4 is used to replace raw material A-1, and raw material B-5 is used to replace raw material B-1, to obtain intermediate a-5. LC-MS: Measured value: 548.12 ([M+H] + )), theoretical value: 547.19.

[0130] The preparation method of intermediate c-5 is the same as that of intermediate c-1, except that intermediate a-5 is used to replace intermediate a-1, to obtain intermediate c-5. LC-MS: Measured value: 817.31 ([M+H] + )), theoretical value: 816.45.

[0131] The preparation method of Compound 46 is the same as that of Compound 6, except that intermediate c-5 is used to replace intermediate c-1, to obtain Compound 46. 1 1H NMR (400 MHz, Chloroform-d) δ 7.97–7.88 (m, 2H), 7.82–7.78 (m, 1H), 7.65–7.60 (m, 2H), 7.56–7.44 (m, 3H), 7.32–7.22 (m, 7H), 7.19 (m, 1H), 7.13–7.07 (m, 3H), 7.05–6.98 (m, 2H), 1.64–1.37 (s, 9H), 1.36–1.22 (m, 27H). FWHM (measured by Horiba's Fluorolog-3 series fluorescence spectrometer in the thin film state): 28 nm.

[0132] Synthesis of Compound 108 in Example 6:

[0133]

[0134] Under nitrogen protection, 10 mmol of raw material D-6, 10 mmol of raw material E-6, 15 mmol of potassium carbonate, 0.5 mmol of copper, 15 mmol of 18-crown-6 and 70 mL of dichlorobenzene were added to a three-necked flask, and the mixture was refluxed for 18 hours. After the reaction was completed, the organic layer was concentrated under reduced pressure and then purified by silica gel column chromatography to obtain raw material A-6. LC-MS: Measured value: 276.06 ([M+H] + ), theoretical value: 275.17.

[0135] The preparation method of intermediate a-6 is the same as that of intermediate a-1, except that raw material A-6 is used to replace raw material A-1 to obtain intermediate a-6. LC-MS: Measured value: 430.48 ([M+H] + ), theoretical value: 429.11.

[0136] The preparation method of intermediate c-6 is the same as that of intermediate c-1, except that intermediate a-6 is used to replace intermediate a-1 to obtain intermediate c-6. LC-MS: Measured value: 699.32 ([M+H] + ), theoretical value: 698.37.

[0137] The preparation method of compound 108 is the same as that of compound 6, except that intermediate c-6 is used to replace intermediate c-1 to obtain compound 108. 1 H NMR (400 MHz, Chloroform-d) δ8.02–7.80 (m, 3H), 7.72–7.62 (m, 3H), 7.59–7.11 (m, 16H), 7.05–6.98 (m, 2H), 6.71 (m, 1H), 1.35–1.24 (d, 18H). FWHM (obtained by testing with Horiba's Fluorolog-3 series fluorescence spectrometer in the thin film state): 26 nm.

[0138] Synthesis of compound 117 in Example 7:

[0139]

[0140] The preparation method of raw material A-7 is the same as that of raw material A-6, except that raw material E-7 is used to replace raw material E-6 to obtain raw material A-7. LC-MS: Measured value: 408.19 ([M+H] + ), theoretical value: 407.26.

[0141] The preparation method of intermediate a-7 is the same as that of intermediate a-1, except that raw material A-7 is used to replace raw material A-1 to obtain intermediate a-7. LC-MS: Measured value: 562.31 ([M+H] + ), theoretical value: 561.20.

[0142] The preparation method of intermediate c-7 is the same as that of intermediate c-1, except that intermediate a-7 is used to replace intermediate a-1 to obtain intermediate c-7. LC-MS: Measured value: 831.60 ([M+H] + ) and the theoretical value is 830.46.

[0143] The preparation method of compound 117 is the same as that of compound 6, except that intermediate c-7 is used to replace intermediate c-1 to obtain compound 117. 1 H NMR (400 MHz, Chloroform-d) δ 8.03–7.88 (m, 3H), 7.81–7.60 (m, 3H), 7.59–7.11 (m, 22H), 1.52–1.38 (s, 9H), 1.33–1.25 (d, 18H). FWHM (obtained by testing with Horiba's Fluorolog-3 series fluorescence spectrometer in the thin film state): 29 nm.

[0144] Synthesis of compound 126 in Example 8:

[0145]

[0146] The preparation method of intermediate a-8 is the same as that of intermediate a-1, except that raw material A-6 is used to replace raw material A-1 and raw material B-8 is used to replace raw material B-1 to obtain intermediate a-8. LC-MS: Measured value: 562.11 ([M+H] + ) and the theoretical value is 561.20.

[0147] The preparation method of intermediate c-8 is the same as that of intermediate c-1, except that intermediate a-8 is used to replace intermediate a-1 to obtain intermediate c-8. LC-MS: Measured value: 831.33 ([M+H] + ) and the theoretical value is 830.46.

[0148] The preparation method of compound 126 is the same as that of compound 6, except that intermediate c-8 is used to replace intermediate c-1 to obtain compound 126. 1 H NMR (400 MHz, Chloroform-d) δ 8.35 (d, 1H), 8.01–7.85 (m, 3H), 7.80–7.60 (m, 5H), 7.58–7.14 (m, 16H), 7.08–6.97 (m, 2H), 6.71 (m, 1H), 1.40–1.25 (m, 27H). FWHM (obtained by testing with Horiba's Fluorolog-3 series fluorescence spectrometer in the thin film state): 26 nm.

[0149] Synthesis of Compound 136 in Example 9:

[0150]

[0151] The preparation method of Intermediate a-9 is the same as that of Intermediate a-1, except that raw material A-9 is used to replace raw material A-1 to obtain Intermediate a-9. LC-MS: Measured value: 486.27 ([M+H] + ), Theoretical value: 485.08.

[0152] The preparation method of Intermediate c-9 is the same as that of Intermediate c-1, except that Intermediate a-9 is used to replace Intermediate a-1 to obtain Intermediate c-9. LC-MS: Measured value: 755.21 ([M+H] + ),Theoretical value: 754.34.

[0153] The preparation method of Compound 136 is the same as that of Compound 6, except that Intermediate c-9 is used to replace Intermediate c-1 to obtain Compound 136. 1 H NMR (400 MHz, Chloroform-d) δ 8.50–8.40 (m, 1H), 7.95–7.86 (m, 2H), 7.80 (s, 1H), 7.74–7.52 (m, 6H), 7.49–7.37 (m, 3H), 7.32–7.26 (m, 4H), 7.24–7.07 (m, 6H), 7.01–6.98 (m, 2H), 1.41–1.28 (d, 18H). FWHM (obtained by testing with Horiba's Fluorolog-3 series fluorescence spectrometer in the thin film state): 27 nm.

[0154] The structural characterization of the compounds obtained in each example is shown in Table 1

[0155] Table 1

[0156]

[0157] The application effects of the OLED materials synthesized in the present invention in the devices are described in detail below through Device Examples 1-9 and Device Comparative Examples 1-3. The manufacturing processes of the devices in Device Examples 2-9 and Device Comparative Examples 1-3 are exactly the same as those in Device Example 1, and the same substrate materials and electrode materials are used, and the film thicknesses of the electrode materials are also kept consistent. The difference is that the light-emitting layer materials in the devices are replaced. The layer structures and test results of each device example are shown in Tables 2 and 3 respectively.

[0158] Device Example 1

[0159] As Figure 1As shown, the transparent substrate layer 1 is a transparent PI film. The ITO anode layer 2 (with a film thickness of 150 nm) is washed, that is, washed successively with a cleaning agent (Semiclean M-L20), pure water, and then dried, and then washed with ultraviolet-ozone to remove organic residues on the surface of the transparent ITO. On the ITO anode layer 2 after the above washing, using a vacuum evaporation device, HT-1 and HI-1 with a film thickness of 10 nm are evaporated as the hole injection layer 3, and the mass ratio of HT-1 and HI-1 is 97:3. Then, HT-1 with a thickness of 60 nm is evaporated as the hole transport layer 4. Subsequently, EB-1 with a thickness of 30 nm is evaporated as the electron blocking layer 5. After the evaporation of the above electron blocking material is completed, the light-emitting layer 6 of the OLED light-emitting device is fabricated. GH-1 and GH-2 are used as the host materials, and compound 6 is used as the doping material. The mass ratio of GH-1, GH-2, and compound 6 is 69:30:1, and the film thickness of the light-emitting layer is 30 nm. After the above light-emitting layer 6, HB-1 is continuously vacuum-evaporated with a film thickness of 5 nm, and this layer is the hole blocking layer 7. After the above hole blocking layer 7, ET-1 and Liq are continuously vacuum-evaporated, and the mass ratio of ET-1 and Liq is 1:1, with a film thickness of 30 nm, and this layer is the electron transport layer 8. On the electron transport layer 8, a LiF layer with a film thickness of 1 nm is fabricated through a vacuum evaporation device, and this layer is the electron injection layer 9. On the electron injection layer 9, a Mg:Ag electrode layer with a film thickness of 80 nm is fabricated through a vacuum evaporation device, and the mass ratio of Mg and Ag is 1:9, and this layer is used as the cathode layer 10.

[0160] The application effects of the OLED materials synthesized by the present invention in the devices are described in detail below through device Examples 10-18 and device Comparative Examples 4-6. The manufacturing processes of the devices in device Examples 11-18 and device Comparative Examples 4-6 are exactly the same as those in device Example 10, and the same substrate materials and electrode materials are used, and the film thicknesses of the electrode materials are also kept consistent. The difference is that the light-emitting layer materials in the devices are replaced. The layer structures and test results of each device example are shown in Tables 2 and 3 respectively.

[0161] Device Example 10

[0162] The transparent substrate layer 1 is a transparent PI film. The ITO anode layer 2 (with a film thickness of 150 nm) is washed, that is, washed successively with a cleaning agent (Semiclean M-L20), pure water, and then dried, and then washed with ultraviolet-ozone to remove organic residues on the surface of the transparent ITO. On the ITO anode layer 2 after the above-mentioned washing, using a vacuum evaporation device, HT-1 and HI-1 with a film thickness of 10 nm are evaporated as the hole injection layer 3, and the mass ratio of HT-1 and HI-1 is 97:3. Then, HT-1 with a thickness of 60 nm is evaporated as the hole transport layer 4. Subsequently, EB-1 with a thickness of 30 nm is evaporated as the electron blocking layer 5. After the evaporation of the above-mentioned electron blocking material is completed, the light-emitting layer 6 of the OLED light-emitting device is fabricated. GH-1 and GH-2 are used as the host materials, GD-1 is used as the first doping material, and compound 6 is used as the second doping material. The mass ratio of GH-1, GH-2, GD-1, and compound 6 is 66:30:3:1, and the film thickness of the light-emitting layer is 30 nm. After the above-mentioned light-emitting layer 6, HB-1 is continuously vacuum-evaporated with a film thickness of 5 nm, and this layer is the hole blocking layer 7. After the above-mentioned hole blocking layer 7, ET-1 and Liq are continuously vacuum-evaporated, and the mass ratio of ET-1 and Liq is 1:1, with a film thickness of 30 nm, and this layer is the electron transport layer 8. On the electron transport layer 8, a LiF layer with a film thickness of 1 nm is fabricated through a vacuum evaporation device, and this layer is the electron injection layer 9. On the electron injection layer 9, a Mg:Ag electrode layer with a film thickness of 80 nm is fabricated through a vacuum evaporation device, and the mass ratio of Mg and Ag is 1:9, and this layer is used as the cathode layer 10.

[0163] The molecular structural formulas of the related materials are as follows:

[0164]

[0165] After the OLED light-emitting device is completed as described above, the anode and the cathode are connected by a well-known driving circuit, and the voltage, current efficiency, and lifetime of the device are measured. The device examples and comparative examples prepared by the same method are shown in Table 2; the test results of the voltage, current efficiency, and lifetime of the obtained devices are shown in Table 3.

[0166] Table 2

[0167]

[0168]

[0169] Table 3

[0170]

[0171]

[0172] Note: The voltage, current efficiency, and emission peak were measured using an IVL (current-voltage-luminance) test system (Suzhou Fushida Scientific Instruments Co., Ltd.); the lifetime test system is the EAS-62C type OLED device lifetime tester from System Technology Research Co., Ltd. of Japan; LT95 refers to the time it takes for the device brightness to decay to 95%; all data were measured at 10 mA / cm 2 under the test.

[0173] From the device data results in Table 3, it can be seen that compared with Device Comparative Examples 1-3, the device lifetime of the compound of the present invention in the single-doping system device is higher than that of the comparative examples; in the single-doping system device, the device efficiency also shows good results. This is because such a boron-nitrogen fused-ring parent nucleus can enhance the resonance intensity and improve the device efficiency without changing the light color; compared with Device Comparative Examples 4-6, in the double-doping system device using an exciton sensitizing material as the first doping, both the current efficiency and the device lifetime of the device are significantly improved compared to the OLED devices of known materials, and in the double-doping device, the device efficiency is also significantly improved compared to the single-doping case.

[0174] In summary, the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A boron-containing organic compound, characterized in that, The structure of the boron-containing organic compound is shown in the general formula (4): In the general formula (4), X1 represents O or S; Ar2 represents one of a substituted or unsubstituted phenyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted dibenzofuranyl group, and a substituted or unsubstituted dibenzothiophenyl group; Each occurrence of Z, which may be the same or different, represents C-R1; Each occurrence of Z1, which may be the same or different, represents C-R2; Each occurrence of Z2, which may be the same or different, represents C-R3; Z1 and Z2 may also be connected by a single bond; Each occurrence of R1, R2, and R3, which may be the same or different, represents a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a phenyl-substituted amino group, a tert-butylbenzene-substituted amino group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group; Ar1 represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group; The substituents for the substituting groups are each independently selected from one or more of a deuterium atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, and an aryl group having 6 to 30 carbon atoms; The heteroatom in the heteroaryl group is arbitrarily selected from one or more of oxygen, sulfur, nitrogen, and silicon atoms; 2. A boron-containing organic compound, characterized in that, The structure of the organic compound is shown in any one of the general formulas (Ⅲ-1) to (Ⅲ-4): In the general formulas (Ⅲ-1) to (Ⅲ-4), X1 represents O or S; Each occurrence of Z, which may be the same or different, represents C-R1; Each occurrence of R1, which is the same or different, represents a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a phenyl-substituted amino group, a tert-butylbenzene-substituted amino group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group; Ar1 represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group; R a 、R c 、R d 、R e Each occurrence, which may be the same or different, is one of a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a phenyl-substituted amino group, a tert-butylbenzene-substituted amino group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group; R b Represents a deuterium atom, a halogen atom, a cyano group, C1-C 10 alkyl group, C3-C 10 cycloalkyl group, C6-C 30 aryl group, C2-C 30 heteroaryl group; The substituents for the substituting groups are each independently selected from one or more of a deuterium atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, and an aryl group having 6 to 30 carbon atoms; The heteroatom in the heteroaryl group is arbitrarily selected from one or more of oxygen, sulfur, nitrogen, and silicon atoms; 3. The boron-containing organic compound according to claim 1, wherein R1, R2, and R3 represent one of a hydrogen atom, a deuterium atom, a halogen atom, an adamantyl group, a methyl group, a deuterated methyl group, a trifluoromethyl group, an ethyl group, a deuterated ethyl group, an isopropyl group, a deuterated isopropyl group, a tert-butyl group, a deuterated tert-butyl group, a cyclopentyl group, a deuterated cyclopentyl group, a methyl-substituted cyclopentyl group, a cyclohexyl group, a phenyl group, a deuterated phenyl group, a biphenyl group, a deuterated biphenyl group, a terphenyl group, a deuterated terphenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a pyridyl group, a phenyl-substituted pyridyl group, a quinolinyl group, a furyl group, a thiophenyl group, a benzofuranyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a carbazolyl group, an N-phenylcarbazolyl group, a 9,9-dimethylfluorenyl group, a spirofluorene group, a methyl-substituted phenyl group, an ethyl-substituted phenyl group, an isopropyl-substituted phenyl group, a tert-butyl-substituted phenyl group, a methyl-substituted biphenyl group, an ethyl-substituted biphenyl group, an isopropyl-substituted biphenyl group, a tert-butyl-substituted biphenyl group, a deuterated methyl-substituted phenyl group, a deuterated ethyl-substituted phenyl group, a deuterated isopropyl-substituted phenyl group, a deuterated tert-butyl-substituted phenyl group, a deuterated methyl-substituted biphenyl group, a deuterated ethyl-substituted biphenyl group, a deuterated isopropyl-substituted biphenyl group, a deuterated tert-butyl-substituted biphenyl group, a phenyl-substituted amino group, a tert-butylbenzene-substituted amino group, a tert-butyl-substituted dibenzofuranyl group, a phenyl-substituted tert-butyl group, an xanthone group, and a phenyl-substituted triazinyl group; Ar1 represents one of a hydrogen atom, a deuterium atom, an adamantyl group, a methyl group, a deuterated methyl group, a trifluoromethyl group, an ethyl group, a deuterated ethyl group, an isopropyl group, a deuterated isopropyl group, a tert-butyl group, a deuterated tert-butyl group, a cyclopentyl group, a deuterated cyclopentyl group, a methyl-substituted cyclopentyl group, a cyclohexyl group, a phenyl group, a deuterated phenyl group, a biphenyl group, a deuterated biphenyl group, a terphenyl group, a deuterated terphenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a pyridyl group, a phenyl-substituted pyridyl group, a quinolinyl group, a furyl group, a thienyl group, a benzofuryl group, a dibenzofuryl group, a dibenzothienyl group, a carbazolyl group, an N-phenylcarbazolyl group, a 9,9-dimethylfluorenyl group, a spirofluorene group, a methyl-substituted phenyl group, an ethyl-substituted phenyl group, an isopropyl-substituted phenyl group, a tert-butyl-substituted phenyl group, a methyl-substituted biphenyl group, an ethyl-substituted biphenyl group, an isopropyl-substituted biphenyl group, a tert-butyl-substituted biphenyl group, a deuterated methyl-substituted phenyl group, a deuterated ethyl-substituted phenyl group, a deuterated isopropyl-substituted phenyl group, a deuterated tert-butyl-substituted phenyl group, a deuterated methyl-substituted biphenyl group, a deuterated ethyl-substituted biphenyl group, a deuterated isopropyl-substituted biphenyl group, a deuterated tert-butyl-substituted biphenyl group, a tert-butyl-substituted dibenzofuryl group, a phenyl-substituted tert-butyl, an xanthenone group, a phenyl-substituted triazinyl group; The substituents for the substitution groups are optionally selected from one or more of a deuterium atom, a fluorine atom, a cyano group, a methyl group, a tert-butyl group, an isopropyl group, a phenyl group, a naphthyl group, and a pyridyl group.

4. The boron-containing organic compound according to claim 2, wherein The R1, R a , R c , R d , R e is represented by one of a hydrogen atom, a deuterium atom, a halogen atom, an adamantyl group, a methyl group, a deuterated methyl group, a trifluoromethyl group, an ethyl group, a deuterated ethyl group, an isopropyl group, a deuterated isopropyl group, a tert-butyl group, a deuterated tert-butyl group, a cyclopentyl group, a deuterated cyclopentyl group, a methyl-substituted cyclopentyl group, a cyclohexyl group, a phenyl group, a deuterated phenyl group, a biphenyl group, a deuterated biphenyl group, a terphenyl group, a deuterated terphenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a pyridyl group, a phenyl-substituted pyridyl group, a quinolinyl group, a furyl group, a thienyl group, a benzofuryl group, a dibenzofuryl group, a dibenzothienyl group, a carbazolyl group, an N-phenylcarbazolyl group, a 9,9-dimethylfluorenyl group, a spirofluorene group, a methyl-substituted phenyl group, an ethyl-substituted phenyl group, an isopropyl-substituted phenyl group, a tert-butyl-substituted phenyl group, a methyl-substituted biphenyl group, an ethyl-substituted biphenyl group, an isopropyl-substituted biphenyl group, a tert-butyl-substituted biphenyl group, a deuterated methyl-substituted phenyl group, a deuterated ethyl-substituted phenyl group, a deuterated isopropyl-substituted phenyl group, a deuterated tert-butyl-substituted phenyl group, a deuterated methyl-substituted biphenyl group, a deuterated ethyl-substituted biphenyl group, a deuterated isopropyl-substituted biphenyl group, a deuterated tert-butyl-substituted biphenyl group, a phenyl-substituted amino group, a tert-butylbenzene-substituted amino group, a tert-butyl-substituted dibenzofuryl group, a phenyl-substituted tert-butyl group, an oxanthrone group, a phenyl-substituted triazinyl group; Ar1 represents one of a hydrogen atom, a deuterium atom, an adamantyl group, a methyl group, a deuterated methyl group, a trifluoromethyl group, an ethyl group, a deuterated ethyl group, an isopropyl group, a deuterated isopropyl group, a tert-butyl group, a deuterated tert-butyl group, a cyclopentyl group, a deuterated cyclopentyl group, a methyl-substituted cyclopentyl group, a cyclohexyl group, a phenyl group, a deuterated phenyl group, a biphenyl group, a deuterated biphenyl group, a terphenyl group, a deuterated terphenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a pyridyl group, a phenyl-substituted pyridyl group, a quinolinyl group, a furyl group, a thienyl group, a benzofuryl group, a dibenzofuryl group, a dibenzothienyl group, a carbazolyl group, an N-phenylcarbazolyl group, a 9,9-dimethylfluorenyl group, a spirofluorene group, a methyl-substituted phenyl group, an ethyl-substituted phenyl group, an isopropyl-substituted phenyl group, a tert-butyl-substituted phenyl group, a methyl-substituted biphenyl group, an ethyl-substituted biphenyl group, an isopropyl-substituted biphenyl group, a tert-butyl-substituted biphenyl group, a deuterated methyl-substituted phenyl group, a deuterated ethyl-substituted phenyl group, a deuterated isopropyl-substituted phenyl group, a deuterated tert-butyl-substituted phenyl group, a deuterated methyl-substituted biphenyl group, a deuterated ethyl-substituted biphenyl group, a deuterated isopropyl-substituted biphenyl group, a deuterated tert-butyl-substituted biphenyl group, a tert-butyl-substituted dibenzofuryl group, a phenyl-substituted tert-butyl, an xanthenone group, a phenyl-substituted triazinyl group; The R b is one of a deuterium atom, a halogen atom, an adamantyl group, a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, a cyclopentyl group, a cyclohexyl group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, a pyridyl group, a quinolinyl group, a furyl group, a thienyl group, a benzofuryl group, a dibenzofuryl group, a dibenzothienyl group, a carbazolyl group, an N-phenylcarbazolyl group, a 9,9-dimethylfluorenyl group, a spirofluorene group, a phenyl-substituted amino group, a tert-butylbenzene-substituted amino group, and an xanthone group; The substituents for the substitution groups are optionally selected from one or more of a deuterium atom, a fluorine atom, a cyano group, a methyl group, a tert-butyl group, an isopropyl group, a phenyl group, a naphthyl group, and a pyridyl group.

5. A boron-containing organic compound, characterized in that, The specific structural formula of the organic compound is any one of the following structures:

6. An organic electroluminescent device, comprising a cathode and an anode, and an organic light-emitting functional layer therebetween, the organic light-emitting functional layer including a light-emitting layer, characterized in that, The light-emitting layer contains the boron-containing organic compound according to any one of claims 1-5.

7. The organic electroluminescent device according to claim 6, wherein the light-emitting layer comprises a host material and a doping material, and the doping material contains the boron-containing organic compound according to any one of claims 1-5.

8. The organic electroluminescent device according to claim 6, wherein the light-emitting layer comprises a first host material, a second host material, and a doping material, characterized in that, At least one of the first host material and the second host material is a TADF material, and the doping material contains the boron-containing organic compound according to any one of claims 1-5.

9. The organic light-emitting device according to claim 6, wherein the light-emitting layer comprises a host material, an exciton sensitizing material, and a doping material, characterized in that, The exciton sensitizing material is a complex containing a metal element, and the doping material contains the boron-containing organic compound according to any one of claims 1-5.

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