Electroluminescent material and organic electroluminescent device

Abstract

The application belongs to the technical field of organic electroluminescent materials, and provides an electroluminescent material and an organic electroluminescent device, wherein the electroluminescent material comprises a combination of a first organic material and a second organic material, the first organic material has a structure as shown in formula I, and the second organic material has a structure as shown in formula II. Through structural design and synergistic compounding of the two types of organic materials, the electroluminescent material has excellent photoelectric performance, higher carrier mobility and material stability, realizes balanced transmission of carriers, and is used in the organic electroluminescent device, so that the device has excellent luminous efficiency and stability, the device voltage is reduced, the device life is significantly prolonged, the comprehensive performance of the device is improved, and the requirements for high-performance materials in current panel and display manufacturing are fully met.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic electroluminescent materials, and particularly relates to an electroluminescent material and an organic electroluminescent device. BACKGROUND

[0002] In recent years, optoelectronic devices based on organic materials have developed very rapidly and gradually become a research hotspot in the field. Examples of organic optoelectronic devices include organic light-emitting diodes (OLEDs), organic field-effect transistors, organic photovoltaic cells, organic sensors, etc., among which the development of OLEDs is particularly rapid and has achieved commercial success in the field of information display. OLEDs can provide high-saturation red, green and blue colors, and full-color display devices made of OLEDs do not require an additional backlight source, and have the advantages of colorful, flexible, light and thin, low cost, high efficiency, low energy consumption, etc.

[0003] The core of an OLED device is a multi-layer thin film structure containing various functional organic materials. Common functional organic materials include hole injection materials, hole transport materials, hole blocking materials, electron injection materials, electron transport materials, electron blocking materials, light-emitting host materials, and light-emitting guest materials (dyes), etc. When powered on, electrons and holes are injected and transported to the light-emitting region and recombine there, generating excitons and emitting light.

[0004] Current OLEDs can be divided into fluorescent light-emitting, phosphorescent light-emitting, thermally activated delayed fluorescence, and thermally activated sensitized fluorescence according to the light-emitting mechanism. Common fluorescent light-emitters mainly utilize the singlet excitons generated when electrons and holes combine to emit light, and are still widely used in various OLED products. Some metal complexes (such as iridium complexes, platinum complexes) can utilize both triplet excitons and singlet excitons for light emission, and are called phosphorescent light-emitters, which can improve the energy conversion efficiency by up to 4 times compared to traditional fluorescent light-emitters. Thermally activated delayed fluorescence (TADF) promotes the transition of triplet excitons to singlet excitons, and can effectively utilize triplet excitons to achieve high light-emitting efficiency without using metal complexes. Thermally activated sensitized fluorescence (TASF) technology uses materials with TADF properties to sensitize light-emitters through energy transfer, which can also achieve high light-emitting efficiency.

[0005] Although products using OLED technology have been commercialized, there is still a need to continuously improve the performance of devices such as efficiency, voltage, and lifetime to meet people's pursuit of high-quality display effects. Therefore, there is an urgent need in the art to develop more types and higher performance organic materials, which are applied to organic electroluminescent devices to make the devices have better light-emitting effect. SUMMARY

[0006] To address the shortcomings of existing technologies, the present invention aims to provide an electroluminescent material and an organic electroluminescent device. Through the structural design of the first organic material and the second organic material and their mutual compounding, the electroluminescent material possesses excellent photoelectric properties and carrier transport characteristics. It is particularly suitable as the main material of the light-emitting layer in organic electroluminescent devices, which can effectively improve the luminous efficiency and lifespan of the device and reduce the voltage.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides an electroluminescent material comprising a combination of a first organic material and a second organic material; the first organic material having a structure as shown in Formula I:

[0009] Formula I.

[0010] In Formula I, X1 and X2 are each independently selected from N, O or S, and one of X1 and X2 is N.

[0011] In Formula I, Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-C30 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups.

[0012] In Formula I, L1, L2, and L3 are each independently selected from any one of the following: single bond, substituted or unsubstituted C6-C30 arylene, and substituted or unsubstituted C3-C30 heteroarylene. When L1 is a single bond, it represents that Ar1 and N atoms are directly connected by a single bond; when L2 is a single bond, it represents that a fused ring structure is directly connected to N atoms by a single bond; when L3 is a single bond, it represents that a dibenzofuran structure is directly connected to N atoms by a single bond.

[0013] In Formula I, R1 is selected from any one of deuterium, substituted or unsubstituted C1-C30 straight-chain or branched alkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C6-C30 arylamino, and substituted or unsubstituted C3-C30 heteroarylamino.

[0014] In Formula I, R2, R3, R4, and R5 are each independently selected from any one of deuterium, halogen, cyano, substituted or unsubstituted C1-C30 straight-chain or branched alkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C6-C30 arylamino, and substituted or unsubstituted C3-C30 heteroarylamino; at least two adjacent groups among R1, R2, R3, R4, and R5 are not connected or are linked by chemical bonds to form a ring.

[0015] In this invention, "at least two adjacent groups among R1, R2, R3, R4, and R5 are not connected" means that the group is only connected to the C atom through a single bond; "at least two adjacent groups among R1, R2, R3, R4, and R5 are connected to form a ring through chemical bonds" means that in addition to being connected to the C atom through chemical bonds, adjacent groups are also connected through chemical bonds, thereby forming a fused ring structure. The same descriptions will have the same meaning in the following text and will not be repeated hereafter.

[0016] In Formula I, a, b, c, d, and e represent the number of substituents R1, R2, R3, R4, and R5, respectively. a is an integer selected from 1 to 3, for example, 1, 2, or 3; b and c are each independently selected from 0 to 4, for example, 0, 1, 2, 3, or 4; d and e are each independently selected from 0 to 2, for example, 0, 1, or 2; 0 ≤ c + d + e ≤ 7.

[0017] It should be noted that when a ≥ 2, multiple (at least 2) R1 groups are the same or different groups. When b is 0, it indicates that there are no substituents on the corresponding benzene ring, and all four sites on the benzene ring are hydrogen atoms; when b ≥ 2, the two R2 groups are the same or different groups. The expressions for c, d, and e are similar, and for the sake of brevity, they will not be repeated. Similar descriptions in the following text have similar meanings.

[0018] The substituents in Ar1, Ar2, L1, L2, L3, R1, R2, R3, R4, and R5 are each independently selected from at least one of deuterium, C1-C20 straight-chain or branched alkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C2-C20 alkenyl, C1-C20 alkoxy, carboxyl, nitro, cyano, amino, hydroxyl, mercapto, C1-C20 alkylsilyl, C1-C20 alkylamino, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 aryl, and C3-C30 heteroaryl, and the substituents are optionally substituted with deuterium; at least two adjacent groups in the substituents are not connected to each other or are connected to each other by chemical bonds to form a ring, and each substituent is independently not connected to the adjacent ring structure or is connected to each other by chemical bonds to form a ring.

[0019] In this invention, "each of the substituents is independently not connected to the adjacent ring structure" means that the substituent is only connected to the C atom through a single bond; "each of the substituents is independently connected to the adjacent ring structure through chemical bonds to form a ring" means that the substituent, in addition to being connected to the C atom through chemical bonds, is also connected to the adjacent ring through chemical bonds, thereby forming a fused ring structure. The same descriptions will have the same meaning in the following text and will not be repeated hereafter.

[0020] In this invention, the dashed arc in Formula I represents the conjugated double bond in the pentagonal ring, that is, the structure of the first organic material is as shown in Formula I1 or Formula I2, preferably the structure shown in Formula I1:

[0021] .

[0022] In Equation I1, X1 is either O or S. In Equation I2, X2 is either O or S.

[0023] The second organic material has a structure as shown in Formula II:

[0024] Formula II.

[0025] In Formula II, Ar3 and Ar4 are each independently selected from any one of substituted or unsubstituted C6-C30 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups.

[0026] In Formula II, L4 is selected from any one of a single bond, a substituted or unsubstituted C6-C30 arylene, or a substituted or unsubstituted C3-C30 heteroarylene; when L4 is a single bond, it means that the triazine structure and the dibenzofuran structure are directly linked by a single bond.

[0027] In Formula II, R6 is selected from any one of deuterium, halogen, cyano, substituted or unsubstituted C1-C30 straight-chain or branched alkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C6-C30 arylamino, and substituted or unsubstituted C3-C30 heteroarylamino; at least two adjacent groups in R6 are not connected or are linked by chemical bonds to form a ring.

[0028] In Formula II, f represents the number of substituents R6, and f is an integer selected from 0 to 4, for example, it can be 0, 1, 2, 3 or 4.

[0029] The substituents in Ar3, Ar4, L4, and R6 are each independently selected from at least one of deuterium, C1-C20 straight-chain or branched alkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C2-C20 alkenyl, C1-C20 alkoxy, carboxyl, nitro, cyano, amino, hydroxyl, mercapto, C1-C20 alkylsilyl, C1-C20 alkylamino, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 aryl, and C3-C30 heteroaryl, and the substituents are optionally substituted with deuterium; at least two adjacent groups in the substituents are not connected or are linked to form a ring by chemical bonds; each of the substituents is independently not connected to an adjacent ring structure or is linked to form a ring by chemical bonds.

[0030] In this invention, the "substituted or unsubstituted" group can replace one substituent or multiple substituents. When there are multiple substituents (at least two), they can be the same or different substituents. The same expression used below has the same meaning. Unless otherwise specified, the selection range of substituents in the first organic material shown in Formula I and the second organic material shown in Formula II is as shown above and will not be repeated.

[0031] The electroluminescent material provided by the present invention comprises a combination of a first organic material and a second organic material. Among them, the first organic material has an arylamine structure shown in Formula I, which contains dibenzofuran and a specific phenanthro[1,9-bc]oxazole / phenanthro[1,9-bc]thiazole structure, and has a high hole mobility; the second organic material has a structure shown in Formula II, which contains a triazine structure with electron-withdrawing properties and a specific dibenzofuran structure, endowing it with excellent planar conjugation properties, good electron mobility and good stability. Through the structural design and synergistic compounding of two types of organic materials with specific structures, the electroluminescent material of the present invention has excellent optoelectronic properties and carrier transport properties, can obtain higher mobility and better carrier transport effect, promote the rapid transfer of excited state excitons, endow the device with lower voltage, higher luminous efficiency, longer lifespan and excellent comprehensive performance, and fully meet the requirements for high-performance materials in current panel and display manufacturing.

[0032] It should be noted that for the convenience of description in the present invention, the possible functions of each group / feature of the organic compound are described separately, but this does not mean that these groups / features act independently. In fact, the reason for obtaining good performance is essentially the optimized design of the entire molecular structure, which is the result of the synergistic effect between each group, rather than the effect of a single group.

[0033] The following are the preferred technical solutions of the present invention, but do not limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the purpose and beneficial effects of the present invention can be better achieved.

[0034] In the present invention, for the description of chemical elements, unless otherwise specified, the concept of isotopes with the same chemical properties is included. For example, hydrogen (H) includes 1 H (protium), 2 H (deuterium, D), 3 H (tritium, T), etc.; carbon (C) includes 12 C, 13 C, etc.

[0035] In the present invention, the hydrogen at any site in the first organic material can be optionally replaced by deuterium, and the hydrogen at any site in the second organic material can be optionally replaced by deuterium.

[0036] In the present invention, the halogen can be fluorine, chlorine, bromine or iodine. The same description involved below has the same meaning.

[0037] In the present invention, unless otherwise specified, the heteroatoms of heteroaryl are selected from N, O, S, P, B, Si or Se, preferably N, O or S. The heteroatoms of heterocyclic alkyl are selected from N, O, S, P, B, Si or Se, preferably N, O or S.

[0038] In this invention, the way the ring structure is represented by "—" indicates that the connection point is located at any position on the ring structure where bonding can occur.

[0039] In this invention, "—*" and "*" both represent the linking site of a functional group.

[0040] In this invention, the expression Ca-Cb represents that the group has ab carbon atoms. Unless otherwise specified, the number of carbon atoms does not include the number of carbon atoms of the substituents.

[0041] In this invention, "each independently" means that when there are multiple subjects, they can be the same or different from each other.

[0042] In this invention, C6-C30 can all be C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26 or C28, etc.

[0043] C3-C30 can all be C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26 or C28, etc.

[0044] C1-C30 can all be C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C20, C22, C24, C26 or C28, etc.

[0045] C2-C30 can all be C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C20, C22, C24, C26 or C28, etc.

[0046] C1-C20 can all be C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.

[0047] C3-C20 can all be C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.

[0048] C2-C20 can all be C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.

[0049] In this invention, the C6-C30 aryl group, preferably C6-C24 aryl group, includes monocyclic aryl and fused-ring aryl groups. A monocyclic aryl group refers to a group containing at least one phenyl atom; when containing at least two phenyl atomes, the phenyl groups are linked by single bonds, including but not limited to: phenyl, biphenyl, terphenyl, tetraphenyl, etc. A fused-ring aryl group refers to a group containing at least two aromatic rings, where the aromatic rings share two adjacent carbon atoms fused together, including but not limited to: naphthyl (1-naphthyl, 2-naphthyl), anthraceneyl (1-anthrayl, 2-anthrayl, 9-anthrayl), phenanthryl, indene, fluorenyl and their derivatives (9,9-dimethylfluorenyl, 9,9-diethylfluorenyl, 9,9-dipropylfluorenyl, 9,9-dimethyl ... Examples of aryl groups include 9-dibutylfluorenel, 9,9-dipentylfluorenel, 9,9-dihexylfluorenel, 9,9-diphenylfluorenel, 9,9-dinaphthylfluorenel, phenylmethylfluorenel, spirodifluorenel, benzo[a]fluorenel, etc.), fluoranyl, triphenylene, pyrene (1-pyrene, 2-pyrene, 4-pyrene), peryl, alkyl, triphenylene, and tetraphenyl (1-tetraphenyl, 2-tetraphenyl, 9-tetraphenyl), etc. It should be noted that monocyclic aryl groups and fused-ring aryl groups linked by single bonds also fall under the aryl group category, such as phenylnaphthyl, naphthylphenyl, phenylnaphthylphenyl, and binaphthyl.

[0050] The C3-C30 heteroaryl group, preferably a C3-C20 heteroaryl group, includes monocyclic heteroaryl groups or fused-ring heteroaryl groups. A monocyclic heteroaryl group means that the molecule contains at least one heteroaryl group. When the molecule contains one heteroaryl group and other groups (such as aryl, heteroaryl, etc.), the heteroaryl group and other groups are connected by a single bond, exemplarily including but not limited to: pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, furanyl, thiophene, pyrroleyl, bipyridinyl, phenylpyridinyl, pyridylphenyl, pyrimidinylphenyl, etc. The term "fused-ring heteroaryl" refers to a molecule containing at least one aromatic heterocycle and one aromatic ring (aromatic heterocycle or aromatic ring), and the two share two adjacent atoms fused together in a group, including but not limited to: quinolinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, benzofuranyl, benzothiopheneyl, isobenzofuranyl, isobenzothiopheneyl, indolyl, dibenzofuranyl, dibenzothiopheneyl, naphthobenzofuranyl, naphthobenzothiopheneyl, carbazoleyl and its derivatives (N-phenylcarbazoleyl, N-naphthylcarbazoleyl, benzocarbazoleyl, dibenzocarbazoleyl, indolocarbazoleyl, azacarbazoleyl, etc.), acridineyl, phenothiazinyl, phenotoxazinyl, hydrogenated acridineyl, etc. It should be noted that heteroaryl groups connected by single bonds, as well as aryl groups connected by single bonds, also fall under the category of heteroaryl groups, such as phenyldibenzofuranyl, phenyldibenzothiophenyl, dibenzothiophenylphenyl, dibenzofuranylphenyl, etc.

[0051] Specific examples of the C6-C30 arylene group can be exemplified by removing one hydrogen atom from the aryl group examples above, resulting in a divalent group; specific examples of the C3-C30 heteroarylene group can be exemplified by removing one hydrogen atom from the heteroaryl group examples above, resulting in a divalent group.

[0052] In this invention, a specific example of the C6-C30 arylamino group is a monovalent group obtained by substituting at least one hydrogen atom in -NH2 with the aforementioned aryl group. A specific example of the C3-C30 heteroarylamino group is a monovalent group obtained by substituting at least one hydrogen atom in -NH2 with the aforementioned heteroaryl group.

[0053] In this invention, the C6-C30 aryloxy group is a monovalent group formed by attaching the aforementioned aryl group to O. Specific examples of the C3-C30 heteroaryloxy group include monovalent groups obtained by attaching the aforementioned heteroaryl group to O.

[0054] The C1-C30 straight-chain or branched alkyl group, preferably C1-C16 straight-chain or branched alkyl group, more preferably C1-C10 straight-chain or branched alkyl group, includes, but is not limited to: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-methylbutyl, n-pentyl, isopentyl, neopentyl, n-hexyl, neohexyl, 2-ethylhexyl, n-octyl, n-heptyl, n-nonyl, n-decyl, etc.

[0055] A specific example of the C1-C20 alkylsilyl group is a monovalent group obtained by substituting at least one hydrogen atom in -SiH3 with the aforementioned straight-chain or branched alkyl group. A specific example of the C1-C20 alkylamino group is a monovalent group obtained by substituting at least one hydrogen atom in -NH2 with the aforementioned straight-chain or branched alkyl group.

[0056] Specific examples of the C1-C30 alkoxy and C1-C20 alkoxy groups can be exemplified by the monovalent groups obtained by connecting the above-mentioned straight-chain or branched alkyl groups with O.

[0057] The C2-C20 alkenyl group, preferably C2-C10 alkenyl group, contains at least one C=C, and includes, but is not limited to: vinyl, propenyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, butadienyl, pentadienyl, etc.

[0058] The C3-C30 cycloalkyl, C3-C20 cycloalkyl, preferably C3-C10 cycloalkyl, includes monocycloalkyl or polycycloalkyl. Monocycloalkyl refers to an alkyl group containing a single ring structure, while polycycloalkyl refers to a structure formed by two or more cycloalkyl groups sharing one or more carbon atoms on a ring; exemplary examples include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and adamantyl.

[0059] Specific examples of the C2-C20 heterocyclic alkyl group can be exemplified by a monovalent group formed by replacing one of the ring carbon atoms in the aforementioned cycloalkyl group with a heteroatom. The heteroatom is preferably N, O, or S, and includes, but is not limited to, epoxy group, oxetane group, tetrahydrofuranyl group, tetrahydrothiophenyl group, tetrahydropyrroleyl group, tetrahydropyranyl group, piperidinyl group, piperazineyl group, dioxaneyl group, morpholinyl group, etc.

[0060] Preferably, the first organic material has a structure as shown in Formula IA:

[0061] Formula IA.

[0062] Where X1 is O or S; Ar1, Ar2, L1, L2, L3, R1, R2, R3, R4, R5, a, b, c, d and e have the same range of limitation as in Equation I.

[0063] Preferably, the first organic material has a structure as shown in Formula I-1 or Formula I-2, and more preferably has a structure as shown in Formula I-1:

[0064] ;

[0065] Where X1 is O or S; Ar1, Ar2, L1, L2, L3, R1, R2, R3, R4, R5, a, b, c, d and e have the same range of limitation as in Equation I.

[0066] Preferably, the first organic material has a structure as shown in any one of Formula I-1-1, Formula I-1-2, Formula I-1-3, and Formula I-1-4, and more preferably, a structure as shown in any one of Formula I-1-1, Formula I-1-2, and Formula I-1-3.

[0067] ;

[0068] Wherein, X1 is O or S, more preferably O; Ar1, Ar2, L1, L2, L3, R1, R2, R3, R4, R5, a, b, c, d and e have the same range of limitation as in Formula I.

[0069] Preferably, Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, C18, etc.) aryl groups and substituted or unsubstituted C5-C20 (e.g., C5, C6, C9, C10, C12, C14, C15, C16, or C18, etc.) heteroaryl groups.

[0070] Preferably, Ar1 and Ar2 are each independently selected from any one of the following groups, whether substituted or unsubstituted:

[0071]

[0072] ;

[0073] In this context, —* represents the linking site of a functional group.

[0074] Y1 is selected from O, S, NR 11 or CR 12 R 13 Any one of them.

[0075] Y2 is selected from O or S.

[0076] R 11 R 12 R 13 R 14 Each is independently selected from any one or a combination of at least two of the following: C1-C20 straight-chain or branched alkyl, C6-C30 aryl, C3-C30 heteroaryl, and C2-C20 alkenyl; The R 12 and R 13 They can be either not connected or linked together by chemical bonds to form a ring.

[0077] Preferably, the R 11 R 12 R 13 R 14 Each of the following is independently selected from any one or a combination of at least two of the following: C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl groups, C2-C10 (e.g., C3, C4, C5, C6, C7, C8, C9, etc.) alkenyl groups, and C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.). Further preferred are any one of C1-C6 straight-chain or branched alkyl groups, phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, and naphthylphenyl groups. Even more preferred are methyl or phenyl groups.

[0078] Preferably, the R 12 and R 13 They can form spirofluorene groups either without bonding or by chemical bonds.

[0079] Preferably, the substituents in Ar1 and Ar2 are each independently selected from deuterium, C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl groups, C3-C10 (e.g., C4, C5, C6, C7, C8, C9, etc.) cycloalkyl groups, C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, C18, etc.) aryl groups, and C3-C20 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C15, C16, C18, etc.) heteroaryl groups, or combinations of at least two of them; each substituent is independently not connected to the adjacent ring structure or is connected to the ring structure by a chemical bond to form a ring.

[0080] Preferably, the substituents in Ar1 and Ar2 are each independently selected from deuterium, C1-C6 straight-chain or branched alkyl, phenyl, naphthyl, biphenyl, and pyridyl, and more preferably from deuterium, methyl, ethyl, isopropyl, isobutyl, tert-butyl, tert-amyl, phenyl, naphthyl, biphenyl, and pyridyl.

[0081] More preferably, Ar1 and Ar2 are each independently selected from any one of the following unsubstituted or deuterated groups:

[0082] ;

[0083] In this context, —* represents the linking site of a functional group.

[0084] More preferably, the Ar2 is selected from any one of the following groups that are unsubstituted or deuterated: phenyl, naphthyl, biphenyl, terphenyl, pyridyl.

[0085] Preferably, L1, L2, and L3 are each independently selected from any one of single-bonded, substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C13, C14, C15, C16, or C18, etc.) arylene, and substituted or unsubstituted C5-C20 (e.g., C6, C7, C8, C9, C10, C12, C14, C15, C16, or C18, etc.) heteroaryl.

[0086] Preferably, L1, L2, and L3 are each independently selected from any one of the following groups: single bond, substituted, or unsubstituted:

[0087] ;

[0088] In this context, —* represents the linking site of a functional group.

[0089] Preferably, R1 is selected from substituted or unsubstituted C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl groups, substituted or unsubstituted C2-C10 (e.g., C3, C4, C5, C6, C7, C8, etc.) alkenyl groups, substituted or unsubstituted C3-C10 (e.g., C4, C5, C6, C7, C8, etc.) cycloalkyl groups, and substituted or unsubstituted C6-C20 (e.g., C4, C5, C6, C7, C8, etc.) cycloalkyl groups. Aryl groups (C6, C9, C10, C12, C14, C16, C18, etc.), substituted or unsubstituted C3-C20 groups (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, etc.), heteroaryl groups (C6-C24 groups (e.g., C6, C9, C10, C12, C14, C16, C18, C20, C22, etc.), arylamino groups (C6, C9, C10, C12, C14, C16, C18, C20, C22, etc.), substituted or unsubstituted C Any one of the following 6-C24 (e.g., C6, C9, C10, C12, C14, C16, C18, C20, C22, etc.) heteroarylamino groups, further preferably any one of the following substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C5-C8 cycloalkyl, substituted or unsubstituted C6-C20 aryl, substituted or unsubstituted C3-C20 heteroaryl, substituted or unsubstituted C6-C20 arylamino, substituted or unsubstituted C6-C20 heteroarylamino groups, further preferably any one of the following substituted or unsubstituted groups: C2-C8 alkenyl, cyclohexyl, phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, naphthylphenyl, binaphthyl, pyridyl, di(phenyl)amino, di(biphenyl)amino, (phenyl)(biphenyl)amino, (phenyl)(pyridyl)amino, (biphenyl)(pyridyl)amino, di(pyridyl)amino.

[0090] Preferably, any two adjacent groups in R1 are not connected or are connected by chemical bonds to form a benzene ring.

[0091] And / or, preferably, the R2 is selected from deuterium, substituted or unsubstituted C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl, substituted or unsubstituted C2-C10 (e.g., C3, C4, C5, C6, C7, C8, etc.) alkenyl, substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C14, C16, C18, etc.) aryl, substituted or unsubstituted Any one of the C3-C20 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, etc.) heteroaryl groups, further preferably any one of the substituted or unsubstituted C6-C20 aryl groups, substituted or unsubstituted C3-C20 heteroaryl groups, and further preferably any one of the substituted or unsubstituted groups of the following: phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, naphthylphenyl, binaphthyl, pyridyl.

[0092] Preferably, any two adjacent groups in R2 are not connected or are connected by chemical bonds to form a benzene ring.

[0093] Preferably, the substituents in R1 and R2 are each independently selected from deuterium, C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl groups, C3-C10 (e.g., C4, C5, C6, C7, C8, C9, etc.) cycloalkyl groups, C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) alkoxy groups, and C6-C20 (e.g., C6, C9, C10, C2 ... At least one of the following: aryl (C12, C13, C14, C15, C16 or C18, etc.) and heteroaryl (C3-C20, such as C4, C5, C6, C9, C10, C12, C14, C15, C16 or C18, etc.), further preferably at least one of deuterium and C1-C6 straight-chain or branched alkyl groups, more preferably deuterium, methyl, ethyl, n-propyl, isopropyl, isobutyl, tert-butyl, isobutyl, isopentyl, tert-pentyl, neopentyl or tert-pentyl.

[0094] Preferably, R3, R4, and R5 are each independently selected from any one of deuterium, substituted or unsubstituted C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl groups, substituted or unsubstituted C3-C10 (e.g., C4, C5, C6, C7, C8, C9, etc.) cycloalkyl groups, substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl groups, and substituted or unsubstituted C3-C20 (e.g., C4, C5, C6, C9, C10, C12, C14, C15, C16, or C18, etc.) heteroaryl groups, preferably deuterium, C1-C6 straight-chain or branched alkyl groups, phenyl, naphthyl, biphenyl, or terphenyl.

[0095] It should be noted that the first organic material may optionally be replaced by deuterium; taking the total amount of hydrogen in the first organic material (the total amount of hydrogen before deuteration) as 100%, the number of deuterium is denoted as n. D Then n D It can range from 0% to 100%, for example, it can be 0, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100%, etc.

[0096] The number of deuterium (n) D A value of 0 indicates that the first organic material has not been replaced by deuterium, and the number of deuterium (n) D The value of 100% indicates that all hydrogen in the first organic material is replaced by deuterium.

[0097] Preferably, n D =0, or 5%≤n D ≤100%, further preferred 10%≤n D ≤100%, and even more 20%≤n D ≤90%.

[0098] As a preferred embodiment of the present invention, the first organic material comprises any one or a combination of at least two of the following compounds:

[0099] .

[0100] In the aforementioned compound structures, the number in the upper right corner of the square brackets indicates the number of D atoms in the molecular structure. For example, in P148, "d15" means that 15 H atoms in the molecular structure are replaced by D atoms. Other similar expressions are similar and will not be repeated here.

[0101] Preferably, the second organic material has a structure as shown in any one of Formula II-1, Formula II-2, or Formula II-3, and more preferably has a structure as shown in Formula II-1 or Formula II-2:

[0102]

[0103] ;

[0104] Ar3, Ar4, L4, R6 and f have the same range of definition as in Equation II.

[0105] And / or, f is selected from an integer of 1 to 4, preferably, f is selected from an integer of 1 to 3, and more preferably 1 or 2. When f ≥ 2, the plurality of (at least 2) R6 are the same or different groups.

[0106] Preferably, R6 is selected from any one of substituted or unsubstituted C6-C30 (e.g., C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, or C28, etc.) aryl groups, and substituted or unsubstituted C3-C30 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, or C28, etc.) heteroaryl groups. More preferably, it is selected from any one of the following groups: phenyl, biphenyl, terphenyl, naphthyl, naphthylphenyl, phenylnaphthyl, binaphthyl, anthracene, fluoranthyl, phenanthrene, triphenylene, phenylphenyl, fluoranthylphenyl, phenanthrene, phenyl fluoranthyl, phenylphenanthrene, phenyl triphenylene, phenyl phenanthrene.

[0107] Preferably, the second organic material has a structure as shown in any one of Formula II-1-1, Formula II-1-2, Formula II-1-3, Formula II-2-1, Formula II-2-2, and Formula II-2-3; more preferably, it has a structure as shown in any one of Formula II-1-1, Formula II-1-2, Formula II-2-1, and Formula II-2-2; and even more preferably, it has a structure as shown in Formula II-1-2 or Formula II-2-1.

[0108] ;

[0109] Ar3, Ar4 and L4 have the same range of definition as in Equation II.

[0110] R 61 Selected from any of the substituted or unsubstituted C6-C30 (e.g., C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, or C28, etc.) aryl groups, and substituted or unsubstituted C3-C30 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, or C28, etc.) heteroaryl groups, preferably any of the substituted or unsubstituted groups from the following: phenyl, biphenyl, terphenyl, naphthyl, naphthylphenyl, phenylnaphthyl, binaphthyl, anthracene, fluoranthyl, phenanthrene, triphenylene, phenylphenyl, fluoranthylphenyl, phenanthrene, phenyl fluoranthyl, phenylphenanthrene, phenyl triphenylene, phenyl phenanthrene.

[0111] More preferably, the R 61 Selected from any one of the following groups:

[0112] .

[0113] R6' is selected from any one of deuterium, halogen, cyano, substituted or unsubstituted C1-C30 straight-chain or branched alkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C6-C30 arylamino, and substituted or unsubstituted C3-C30 heteroarylamino, preferably deuterium or substituted or unsubstituted C1-C10 (e.g., C2, C3, C4, C5, C6, C7). Any one of the following: straight-chain or branched alkyl groups (C8, C9, etc.), substituted or unsubstituted C3-C10 (e.g., C4, C5, C6, C7, C8, C9, etc.) cycloalkyl groups, substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16 or C18, etc.) aryl groups, substituted or unsubstituted C3-C20 (e.g., C4, C5, C6, C9, C10, C12, C14, C15, C16 or C18, etc.) heteroaryl groups, preferably deuterium, C1-C6 straight-chain or branched alkyl groups, phenyl, naphthyl, biphenyl, or terphenyl.

[0114] f1 represents the number of substituents R6', which is an integer selected from 0 to 3, for example, it can be 0, 1, 2 or 3, preferably 0 to 1.

[0115] Preferably, Ar3 and Ar4 are each independently selected from any one of substituted or unsubstituted C6-C26 (e.g., C6, C9, C10, C12, C14, C15, C16, C18, C20, C22, C24, C25, etc.) aryl groups and substituted or unsubstituted C5-C20 (e.g., C5, C6, C9, C10, C12, C14, C15, C16, or C18, etc.) heteroaryl groups.

[0116] Preferably, Ar3 and Ar4 are each independently selected from any one of the following groups, whether substituted or unsubstituted:

[0117] ;

[0118] In this context, —* represents the linking site of a functional group.

[0119] Y3 is selected from O, S, NR 21 or CR 22 R 23 Any one of them.

[0120] Y4 is selected from O or S.

[0121] R 21 R 22 R 23 R24 Each is independently selected from any one or a combination of at least two of the following: C1-C20 straight-chain or branched alkyl, C6-C30 aryl, C3-C30 heteroaryl, and C2-C20 alkenyl; The R 22 and R 23 They can be either not connected or linked together by chemical bonds to form a ring.

[0122] Preferably, the R 21 R 22 R 23 R 24 Each of the following is independently selected from any one or a combination of at least two of the following: C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl groups, C2-C10 (e.g., C3, C4, C5, C6, C7, C8, C9, etc.) alkenyl groups, and C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.). Further preferred are any one of C1-C6 straight-chain or branched alkyl groups, phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, and naphthylphenyl groups. Even more preferred are methyl or phenyl groups.

[0123] Preferably, the R 22 and R 23 They can form spirofluorene groups either without bonding or by chemical bonds.

[0124] Preferably, the substituents in Ar3 and Ar4 are each independently selected from deuterium, C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl groups, C3-C10 (e.g., C4, C5, C6, C7, C8, C9, etc.) cycloalkyl groups, C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, C18, etc.) aryl groups, and C3-C20 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C15, C16, C18, etc.) heteroaryl groups, or combinations of at least two of them; each substituent is independently not connected to the adjacent ring structure or is connected to the ring structure by a chemical bond to form a ring.

[0125] Preferably, the substituents in Ar3 and Ar4 are each independently selected from deuterium, C1-C6 straight-chain or branched alkyl, phenyl, naphthyl, biphenyl, and pyridyl, and more preferably from deuterium, methyl, ethyl, isopropyl, isobutyl, tert-butyl, tert-amyl, phenyl, naphthyl, biphenyl, and pyridyl.

[0126] Preferably, Ar3 and Ar4 are each independently selected from any one of the following unsubstituted or deuterated groups:

[0127] ; where —* represents the linking site of the group.

[0128] Preferably, L4 is selected from any one of single-bonded, substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C13, C14, C15, C16 or C18, etc.) arylene, and substituted or unsubstituted C5-C20 (e.g., C6, C7, C8, C9, C10, C12, C14, C15, C16 or C18, etc.) heteroaryl.

[0129] Preferably, the L4 is selected from any one of the following groups: single bond, substituted or unsubstituted.

[0130] ;

[0131] In this context, —* represents the linking site of a functional group.

[0132] As a preferred embodiment of the present invention, the second organic material comprises any one or a combination of at least two of the following compounds:

[0133] .

[0134] In particular, in this invention, the second organic material does not use the following compounds:

[0135]

[0136] .

[0137] Preferably, the mass percentage of the first organic material in the electroluminescent material is 1-99%, such as 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95%, and more preferably 35-75%.

[0138] As a preferred embodiment of the present invention, the electroluminescent material contains 1-99% by mass of the first organic material, preferably 30-80%, more preferably 35-75%, with the remainder being the second organic material.

[0139] In a second aspect, the present invention provides an application of the electroluminescent material as described in the first aspect, wherein the electroluminescent material is applied to an organic electronic device.

[0140] Preferably, the organic electronic device includes an organic electroluminescent device, an optical sensor, a solar cell, a lighting element, an organic thin-film transistor, an organic field-effect transistor, an organic thin-film solar cell, an information tag, an electronic artificial skin sheet, a sheet-type scanner, or electronic paper.

[0141] Preferably, the electroluminescent material is applied to an organic electroluminescent device, and more preferably to a red organic electroluminescent device.

[0142] Preferably, the electroluminescent material is used as a light-emitting layer material in an organic electroluminescent device, more preferably as a host material of the light-emitting layer, and even more preferably as a host material of the red light-emitting layer.

[0143] Thirdly, the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer disposed between the first electrode and the second electrode, the organic layer comprising the electroluminescent material as described in the first aspect.

[0144] Preferably, the organic layer includes a light-emitting layer, wherein the light-emitting layer includes an electroluminescent material as described in the first aspect.

[0145] Preferably, the thickness of the light-emitting layer is 10-60 nm, for example, it can be 12 nm, 15 nm, 18 nm, 20 nm, 22 nm, 25 nm, 28 nm, 30 nm, 32 nm, 35 nm, 38 nm, 40 nm, 42 nm, 45 nm, 48 nm, 50 nm, 52 nm, 55 nm or 58 nm, more preferably 20-50 nm, and more preferably 30-45 nm.

[0146] Preferably, the electroluminescent material is used as the main material of the light-emitting layer.

[0147] As a preferred embodiment of the present invention, the electroluminescent material serves as the main material of the light-emitting layer. It is a dual-main-material system. The first organic material (first main material) is a hole-type main material with good hole transport capability; the second organic material (second main material) is an electron-type main material, mainly responsible for electron transport in the light-emitting layer. The synergistic combination of the two organic materials can achieve a balance between hole and electron transport, avoid the large accumulation of charge carriers at the interface, suppress non-radiative transitions, improve exciton utilization, promote the rapid transfer of excited-state excitons to the guest light source, and significantly improve the overall performance of the device, such as efficiency, lifetime, and voltage.

[0148] Preferably, the light-emitting layer comprises a host material and a dopant material, wherein the host material comprises an electroluminescent material as described in the first aspect.

[0149] Preferably, the doping material (also known as "dye", "guest material", "dopant") is a phosphorescent doping material, and more preferably a red phosphorescent doping material.

[0150] Preferably, based on the mass of the main material as 100%, the mass of the dopant material is 0.1-10%, for example, it can be 0.2%, 0.5%, 0.8%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8% or 9%, etc.

[0151] Preferably, the mass of the doped material is 0.1-10% based on the mass of the electroluminescent material as 100%, for example, 0.2%, 0.5%, 0.8%, 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8% or 9%, etc.

[0152] Preferably, the organic layer further includes a hole transport region and an electron transport region.

[0153] Preferably, the hole transport region includes any one or a combination of at least two of the following: a hole injection layer, a hole transport layer, and an electron blocking layer.

[0154] Preferably, the electron transport region includes any one or a combination of at least two of the electron injection layer, electron transport layer, and hole blocking layer.

[0155] In a preferred embodiment, the organic electroluminescent device (OLED device) includes a first electrode and a second electrode, and an organic layer located between the electrodes. The organic layer can be further divided into multiple regions, such as a hole transport region, a light-emitting layer, and an electron transport region; the light-emitting layer contains the electroluminescent material provided by this invention.

[0156] In a preferred embodiment, the organic electroluminescent device includes a first electrode, a plurality of light-emitting functional layers (organic layers), and a second electrode arranged sequentially. The organic layers include a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer arranged sequentially, with the hole injection layer in contact with the first electrode (anode). The organic layer (preferably the light-emitting layer) contains the electroluminescent material provided by this invention.

[0157] In a preferred embodiment, a substrate can be used below the first electrode or above the second electrode. The substrate is made of glass or polymer material with excellent mechanical strength, thermal stability, water resistance, and transparency. Furthermore, the substrate used for a display can also contain thin-film transistors (TFTs).

[0158] In a preferred embodiment, the first electrode can be formed by sputtering or depositing a material used as the first electrode on a substrate. When the first electrode is used as the anode, it can be a transparent conductive oxide material such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), zinc oxide (ZnO), or any combination thereof. When the first electrode is used as the cathode, it can be a metal or alloy such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), ytterbium (Yb), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), or any combination thereof.

[0159] Organic layers can be formed on electrodes using methods such as vacuum thermal evaporation, spin coating, and printing. The compounds used as organic layers can be small organic molecules, large organic molecules, or polymers, as well as combinations thereof.

[0160] The hole transport region is located between the anode and the emissive layer. The hole transport region can be a single-layer hole transport layer (HTL), including single-layer hole transport layers containing only one compound and single-layer hole transport layers containing multiple compounds. Alternatively, the hole transport region can be a multilayer structure including at least one of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL); wherein the HIL is located between the anode and the HTL, and the EBL is located between the HTL and the emissive layer.

[0161] The material for the hole transport region may be selected from, but is not limited to, phthalocyanine derivatives such as CuPc, conductive polymers or polymers containing conductive dopants such as polyphenylene ethylene, polyaniline / dodecylbenzenesulfonic acid (Pani / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphorsulfonic acid (Pani / CSA), polyaniline / poly(4-styrenesulfonate) (Pani / PSS), aromatic amine derivatives, wherein the aromatic amine derivatives include compounds shown below HT-1 to HT-51; or any combination thereof.

[0162] .

[0163] The hole injection layer is located between the anode and the hole transport layer. The hole injection layer can be a single compound material or a combination of multiple compounds. For example, the hole injection layer can be one or more compounds of HT-1 to HT-51 described above, or one or more compounds of HI-1 to HI-3 described below; it can also be one or more compounds of HT-1 to HT-51 doped with one or more compounds of HI-1 to HI-3 described below.

[0164]

[0165] The light-emitting layer includes a host material (the electroluminescent material provided in this invention) and light-emitting dyes (i.e., dopants) capable of emitting different wavelength spectra. The light-emitting layer can also be a monochromatic light-emitting layer emitting a single color such as red, green, or blue. Multiple monochromatic light-emitting layers of different colors can be arranged in a planar pattern according to pixel design, or they can be stacked together to form a colored light-emitting layer. When different colored light-emitting layers are stacked together, they can be separated from each other or connected to each other. The light-emitting layer can also be a single colored light-emitting layer capable of simultaneously emitting different colors such as red, green, and blue.

[0166] Depending on the technology used, the light-emitting layer material can be various, including fluorescent electroluminescent materials, phosphorescent electroluminescent materials, and thermally activated delayed fluorescence materials. An OLED device can employ a single light-emitting technology or a combination of different technologies. These different light-emitting materials, categorized by technology, can emit light of the same color or different colors.

[0167] In one aspect of the invention, the light-emitting layer employs phosphorescent electroluminescence technology. The main material of the light-emitting layer includes the electroluminescent material provided by the present invention, namely, a combination of a first organic material and a second organic material.

[0168] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent doping material of the light-emitting layer may be selected from, but is not limited to, one or more combinations of RPD-1 to RPD-28 listed below.

[0169] .

[0170] In one aspect of the present invention, an electron blocking layer (EBL) is located between the hole transport layer and the light-emitting layer. The electron blocking layer may be, but is not limited to, one or more compounds of HT-1 to HT-51 described above.

[0171] The organic layer may also include an electron transport region between the light-emitting layer and the cathode. The electron transport region can be a single-layer electron transport layer (ETL), including single-layer electron transport layers containing only one compound and single-layer electron transport layers containing multiple compounds. The electron transport region may also be a multilayer structure including at least one of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL); wherein the HBL is located between the light-emitting layer and the ETL, and the EIL is located between the cathode and the ETL.

[0172] In one aspect of the present invention, the electron transport layer material may be selected from, but not limited to, one or more combinations of ET-1 to ET-73 listed below.

[0173] .

[0174] In one aspect of the invention, a hole blocking layer (HBL) is located between the electron transport layer and the light-emitting layer. The hole blocking layer may employ one or more compounds of ET-1 to ET-73 described above.

[0175] The device may also include an electron injection layer located between the electron transport layer and the cathode. The electron injection layer material includes, but is not limited to, one or more combinations of the following: LiQ, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca, Mg, Yb.

[0176] Fourthly, the present invention also provides a display device, the display device comprising the organic electroluminescent device as described in the third aspect.

[0177] Preferably, the display device includes a display screen or a display panel.

[0178] The present invention also provides an electronic device, which includes the aforementioned display device.

[0179] Compared with the prior art, the present invention has the following beneficial effects:

[0180] The electroluminescent material provided by this invention, through the structural design and synergistic compounding of the first organic material and the second organic material, possesses excellent photoelectric properties, higher carrier mobility, and material stability, achieving balanced carrier transport. When used in organic electroluminescent devices, it is particularly suitable as the host material for the luminescent layer, effectively regulating the injection / transport balance of holes and electrons, preventing excessive carrier accumulation at the interface, promoting energy transfer between host and guest materials, resulting in excellent luminous efficiency and stability, reducing device voltage, significantly extending device lifespan, and improving the overall performance of the device. This fully meets the current requirements for high-performance materials in panel and display manufacturing. Detailed Implementation

[0181] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention.

[0182] In one specific embodiment, the first organic material can be prepared by an organic synthesis method known in the prior art; for example, it can be prepared by the following representative synthetic route:

[0183] ;

[0184] Among them, X1, X2, Ar1, Ar2, L1, L2, L3, R1, R2, R3, R4, R5, a, b, c, d and e have the same definition as in Formula I; Hal1 and Hal2 are each independently selected from any one of the halogens, for example, F, I, Br or Cl, preferably Cl or Br.

[0185] In one specific embodiment, reactions I and II are carried out in the presence of a palladium catalyst. The order of reactions I and II can be adjusted according to the synthesis situation; that is, reaction I can be carried out first, followed by reaction II, or reaction II can be carried out first, followed by reaction I. Usually, reaction I is carried out first, followed by reaction II.

[0186] In one specific embodiment, the second organic material can be prepared by organic synthesis methods known in the prior art; for example, it can be prepared by the following representative synthetic route:

[0187] ;

[0188] Wherein, Ar3, Ar4, L4, R6, and f have the same definitions as in Formula II; Hal3 is selected from any of the halogens, for example, it can be F, I, Br, or Cl, preferably Cl or Br; U1 is selected from any of the following groups: .

[0189] In one specific embodiment, reaction III is carried out in the presence of a palladium catalyst.

[0190] In one specific embodiment, the dibenzofuran-based raw material for preparing the second organic material can be obtained through the following representative synthetic route:

[0191]

[0192] In one specific embodiment, reaction IV is carried out in the presence of a palladium catalyst.

[0193] The specific preparation methods of the first organic material and the second organic material of the present invention will be described in detail below using several synthesis examples, but the preparation methods of the present invention are not limited to these synthesis examples.

[0194] It should be noted that obtaining the first organic material and the second organic material is not limited to the synthesis methods and raw materials used in this invention. Those skilled in the art can also select other methods or routes to obtain the first organic material and the second organic material proposed in this invention.

[0195] The compounds, solvents, and reagents used in the synthesis methods not mentioned in this invention are all commercially available raw materials that can be purchased or customized from the domestic chemical market, or can be prepared in-house using these raw materials according to known methods.

[0196] In the following specific embodiments of the present invention, the intermediates and target products were analyzed and detected using an Agilent HPLC-6500 series Q-TOF liquid chromatography-mass spectrometry system to determine their molecular weights. The ionization source was an atmospheric pressure chemical ionization (APCI) source, and the ionization method was [M+H]. + .

[0197] Synthesis Example 1: Synthesis of Compound P6

[0198]

[0199] (1) Synthesis of M1

[0200] In a 1000 mL single-necked flask, 24 g of SM1, 6.8 g of SM2, 0.5 g of tris(dibenzylacetone)dipalladium(O)Pd2(dba)3, 0.4 g of 1,3-bis(2,6-diisopropylphenyl)imidazolium chloride IPr·HCl, 21.3 g of sodium tert-butoxide, and 400 mL of toluene were added. The mixture was evacuated under vacuum and purged with nitrogen three times. The reaction was heated to 90 °C and reacted for 5 h. After the reaction was complete, the reaction was stopped. The mixture was cooled to room temperature, and the reaction solution was separated. The organic phase was filtered twice through silica gel column chromatography. The concentrated organic phase was then added to methanol and refluxed for 1 h. The mixture was filtered to obtain a pale yellow powder M1, which was then recrystallized from ethyl acetate to obtain 19.2 g of pure product.

[0201] Theoretical m / z value: 386.14; Measured m / z value: 387.17 (APCI source, [M+H]) + ).

[0202] (2) Synthesis of P6

[0203] In a 1000 mL single-necked flask, add 15 g of M1, 10.8 g of SM3, 0.5 g of Pd2(dba)3, 0.4 g of tri-tert-butylphosphine tetrafluoroborate (t-Bu)3PBF4, 12.4 g of sodium tert-butoxide, and 400 mL of toluene. The mixture is evacuated under vacuum and purged with nitrogen three times. The reaction mixture is heated to 110 °C and reacted for 5 h. After the reaction is complete, the reaction is stopped. The mixture is cooled to room temperature, and the reaction solution is separated. The organic phase is filtered twice through silica gel column chromatography. The concentrated organic phase is then added to methanol and refluxed for 1 h. The mixture is filtered to obtain a white powder, P6, which is then recrystallized three times from ethyl acetate to obtain 20.7 g of pure product.

[0204] Theoretical m / z value: 628.22; Measured m / z value: 629.23 (APCI source, [M+H]) + ).

[0205] The process route for synthesis examples 2-16 is the same as that for synthesis example 1, except that the raw materials used are different. The raw materials, target products and result characterization data are shown in Table 1.

[0206] Table 1

[0207]

[0208] Synthesis Example 17: Synthesis of Compound N1

[0209]

[0210]

[0211] (1) Synthesis of M2

[0212] In a 1000 mL single-necked flask, 20 g of SM4, 8.7 g of SM5, 24 g of potassium carbonate, 4 g of tetrakis(triphenylphosphine)palladium Pd(PPh3)4, 350 mL of toluene, 170 mL of H2O, and 170 mL of ethanol were added. The mixture was evacuated under nitrogen three times, and the reaction was heated to 110 °C for 1 h. After the reaction was complete, it was stopped. The mixture was cooled to room temperature, and the organic layer was extracted with ethyl acetate. The remaining water was removed with magnesium sulfate. Subsequently, the organic layer was dried and separated by column chromatography to obtain 13.3 g of compound M2.

[0213] Theoretical m / z value: 278.05; Measured m / z value: 279.08 (APCI source, [M+H]) + ).

[0214] (2) Synthesis of M3

[0215] In a 1000 mL single-necked flask, 12.8 g of M2, 17.5 g of 4,4,4',4',5,5,5',5'-octamethyl-2,2'-bis(1,3,2-dioxaborane), 11.3 g of potassium acetate (KOAc), 3.2 g of bis(triphenylphosphine)palladium dichloride (PdCl2(PPh3)2), and 230 mL of 1,4-dioxane were added. The mixture was evacuated under nitrogen three times, and the reaction was heated to 130 °C for 3 h. After the reaction was complete, it was stopped. The mixture was cooled to room temperature, and the organic layer was extracted with ethyl acetate. The remaining water was removed with magnesium sulfate. The organic layer was then dried and separated by column chromatography to obtain 15.1 g of compound M3.

[0216] Theoretical m / z value: 370.17; Measured m / z value: 371.25 (APCI source, [M+H]) + ).

[0217] (3) Synthesis of N1

[0218] In a 1000 mL single-necked flask, 15 g of compound M3, 8.6 g of compound SM7, 5.5 g of potassium carbonate, 922 mg of Pd(PPh3)4, 80 mL of toluene, 40 mL of ethanol, and 40 mL of water were added. The mixture was evacuated under nitrogen three times, and the reaction was heated to 130 °C for 3 h. After the reaction was complete, it was stopped. The mixture was cooled to room temperature, and the organic layer was extracted with ethyl acetate. The remaining water was removed with magnesium sulfate. The organic layer was then dried and separated by column chromatography to obtain 11.7 g of compound N1.

[0219] Theoretical m / z value: 475.17; Measured m / z value: 476.17 (APCI source, [M+H]) + ).

[0220] The process routes of synthesis examples 18-31 are the same as those of synthesis example 17, except that the raw materials used are different. The raw materials, target products and result characterization data are shown in Table 2.

[0221] Table 2

[0222]

[0223] This invention provides exemplary methods for synthesizing the above-mentioned compounds. Other compounds for which no specific synthesis method is provided can also be prepared using similar methods, requiring only the replacement of raw materials. These methods will not be elaborated here. Alternatively, those skilled in the art can prepare these compounds using other methods in the prior art.

[0224] The electroluminescent material and organic electroluminescent device containing the present invention will be described in detail below using several embodiments as examples, but the electroluminescent material and organic electroluminescent device containing the present invention are not limited to these embodiments.

[0225] Example 1

[0226] An electroluminescent material comprising a first organic material P1 and a second organic material N6, wherein the mass ratio of P1 to N6 is 1:1.

[0227] An organic electroluminescent device, comprising the electroluminescent material provided in this embodiment, includes an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode arranged sequentially; the fabrication method of this organic electroluminescent device is as follows:

[0228] (1) The glass substrate coated with ITO transparent conductive layer was ultrasonically treated in commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in acetone / ethanol mixed solvent, baked in a clean environment until the moisture was completely removed, cleaned with ultraviolet light and ozone, and bombarded with low-energy cation beam.

[0229] (2) Place the glass substrate with the anode into a vacuum chamber and evacuate it to a value less than 1×10⁻⁶. -5 Pa, a mixture of compound HT-29:HI-1 (97 / 3, w / w) was vacuum-deposited on the above anodic layer as a hole injection layer, with a total film thickness of 10 nm.

[0230] (3) A 60 nm layer of compound HT-29 was vacuum-deposited on the hole injection layer as a hole transport layer;

[0231] (4) A 60 nm layer of compound HT-37 was vacuum-deposited on the hole transport layer as an electron blocking layer;

[0232] (5) A light-emitting layer is vacuum-deposited on the electron blocking layer. The light-emitting layer includes a host material (the electroluminescent material, P1:N6=1:1) and a dopant material (dye, RPD-18). The mass ratio (w / w) of the host material and the dopant material is 100:3. The light-emitting layer is deposited by a dual-source co-evaporation method with a deposition rate of 0.1 nm / s and a total deposition thickness of 40 nm.

[0233] (6) A 5 nm layer of compound ET-17 was vacuum-deposited on the light-emitting layer as a hole-blocking layer;

[0234] (7) Vacuum evaporation of an ET-66:ET-57 (50 / 50, w / w) mixture as an electron transport layer on a hole blocking layer, with a total film thickness of 25 nm;

[0235] (8) Vacuum evaporation of 1 nm LiF on the electron transport layer as an electron injection layer;

[0236] (9) Vacuum evaporation of 150 nm of metallic Al on the electron injection layer as a cathode; during the above evaporation process, the evaporation rate of all organic layers and LiF is 0.1 nm / s, and the evaporation rate of the metal is 1 nm / s, to obtain the organic electroluminescent device.

[0237] Examples 2-34, Comparative Examples 1-8

[0238] An electroluminescent material and an organic electroluminescent device comprising the same are disclosed, the only difference from Example 1 being that the electroluminescent material (the main material of the light-emitting layer) is replaced with the compounds in Table 3, and the mass ratio of the first organic material to the second organic material is 1:1; the other structures, materials and preparation methods of the device are the same as those in Example 1; the light-emitting layers of Comparative Examples 4-6 all use a single main material, and the mass ratio of the main material to the dopant material is 100:10.

[0239] The structures of the main materials in Comparative Examples 1-4 are as follows:

[0240]

[0241] The performance of the above-mentioned organic electroluminescent devices was tested using the following methods:

[0242] (1) Under the same brightness, the driving voltage and current efficiency of the organic electroluminescent device were measured using a digital source meter and a luminance meter; specifically, the voltage was increased at a rate of 0.1 V per second, and the current density of the organic electroluminescent device was measured when it reached 10 mA / cm². 2 The voltage at that time is the operating voltage. At the same time, the brightness at that time is measured. The ratio of brightness to current density is the current efficiency.

[0243] (2) The LT97 lifetime was tested as follows: at a constant current density of 60 mA / cm² 2 The time taken for the brightness to decay during testing, such as LT97 lifetime, refers to the time it takes for the brightness to decay to 97% of the initial brightness, in hours.

[0244] With the test values ​​of each performance indicator of Comparative Example 1 recorded as 100%, the ratios of the test values ​​of the performance indicators of other devices to the test values ​​of Comparative Example 1 were calculated; the test results are shown in Table 3:

[0245] Table 3

[0246]

[0247] As can be seen from the performance data in Table 3, the present invention, through the synergistic compounding of a first organic material and a second organic material with a specific structure, enables the electroluminescent material to have better charge injection and energy transmission capabilities, and can achieve balanced carrier transmission. As the main material of the light-emitting layer of an organic electroluminescent device, it can effectively improve the luminous efficiency of the device, significantly extend its lifespan, and reduce the voltage.

[0248] Furthermore, a comparison between Example 6 and Comparative Example 1 shows that the device efficiency of Example 6 is significantly improved while the voltage decreases. This may be because the quaternary carbon in the N1s structure leads to a decrease in the planarity of the molecular structure, resulting in poorer energy transfer and reduced efficiency. Simultaneously, the lack of substitution of the dibenzofuranyl (DBF) group in compound P1s reduces hole transport capability. A comparison of Examples 6-8 with Comparative Examples 2 and 7-8 reveals that the introduction of a phenyl substitution at the 1-position of DBF in compound P4 of the present invention results in a more compact molecular structure. This enhances hole mobility and facilitates molecular stacking, significantly improving film stability and thus significantly improving device lifetime and efficiency. Furthermore, based on the test results of each embodiment and Comparative Examples 4-6 and Example 1, it can be seen that, compared with the single compound host materials commonly used in the industry, the materials provided by the present invention have performance gaps when used alone. However, when used in combination, the present invention, through the synergistic compounding of a first organic material and a second organic material with a specific structure, enables the electroluminescent material to have better charge injection and energy transmission capabilities, thereby reducing the voltage of the device and significantly improving its efficiency and lifespan, thus showing better application prospects.

[0249] The applicant declares that the electroluminescent materials and organic electroluminescent devices of the present invention are illustrated through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials of the products of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. An electroluminescent material, characterized in that, The electroluminescent material comprises a combination of a first organic material and a second organic material; The first organic material has a structure as shown in Formula I: Formula I; Wherein, X1 and X2 are each independently selected from N or O, and one of X1 and X2 is N; Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-C30 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups; L1 is selected from single bonds, , , Any one of them; L2 is selected from single bonds or L3 represents a single bond; —* represents the linking site of a functional group; R1 is selected from any one of phenyl, biphenyl, naphthyl, substituted or unsubstituted cyclohexyl, C6-C30 arylamino, and C3-C30 heteroarylamino; R2, R3, R4, and R5 are each independently selected from any one of deuterium, halogen, cyano, substituted or unsubstituted C1-C30 straight-chain or branched alkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C6-C30 arylamino, and substituted or unsubstituted C3-C30 heteroarylamino. At least two adjacent groups in R1, R2, R3, R4, and R5 are not connected or are linked by chemical bonds to form a ring; a is an integer selected from 1 to 3; b, c, d, and e are all 0; The substituents in Ar1, Ar2, R1, R2, R3, R4, and R5 are each independently selected from at least one of deuterium, C1-C20 straight-chain or branched alkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C2-C20 alkenyl, C1-C20 alkoxy, carboxyl, nitro, cyano, amino, hydroxyl, mercapto, C1-C20 alkylsilyl, C1-C20 alkylamino, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 aryl, and C3-C30 heteroaryl, and the substituents are optionally substituted with deuterium; at least two adjacent groups in the substituents are not connected to each other or are connected to each other by chemical bonds to form a ring, and each substituent is independently not connected to or connected to the adjacent ring structure by chemical bonds to form a ring; The second organic material has a structure as shown in Formula II-1 or Formula II-2: ； Ar3 and Ar4 are each independently selected from any one of the C6-C30 aryl groups; L4 is selected from single bond or ; R6 is selected from any one of the following groups, substituted or unsubstituted: phenyl, biphenyl, terphenyl, naphthyl, naphthylphenyl, phenylnaphthyl, and binaphthyl; at least two adjacent groups in R6 are not connected or are linked by chemical bonds to form a ring; f is an integer selected from 0 to 2; The substituents in R6 are each independently selected from at least one of deuterium, C1-C20 straight-chain or branched alkyl, C3-C20 cycloalkyl, C2-C20 heterocycloalkyl, C2-C20 alkenyl, C1-C20 alkoxy, carboxyl, nitro, cyano, amino, hydroxyl, mercapto, C1-C20 alkylsilyl, C1-C20 alkylamino, C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryloxy, C3-C30 heteroaryloxy, C6-C30 aryl, and C3-C30 heteroaryl, and the substituents are optionally substituted with deuterium; at least two adjacent groups in the substituents are not connected or are linked to form a ring by chemical bonds; each substituent is independently not connected to an adjacent ring structure or is linked to form a ring by chemical bonds.

2. The electroluminescent material according to claim 1, characterized in that, The first organic material has a structure as shown in Formula IA: Formula IA; Where X1 is O; Ar1, Ar2, L1, L2, L3, R1, R2, R3, R4, R5, a, b, c, d and e have the same range of limitation as in Equation I.

3. The electroluminescent material according to claim 1, characterized in that, The first organic material has a structure as shown in Formula I-1 or Formula I-2: ； Where X1 is O; Ar1, Ar2, L1, L2, L3, R1, R2, R3, R4, R5, a, b, c, d and e have the same range of limitation as in Equation I.

4. The electroluminescent material according to claim 1, characterized in that, The first organic material has a structure as shown in any one of Formula I-1-1, Formula I-1-2, Formula I-1-3, or Formula I-1-4: ； Where X1 is O; Ar1, Ar2, L1, L2, L3, R1, R2, R3, R4, R5, a, b, c, d and e have the same range of limitation as in Equation I.

5. The electroluminescent material according to any one of claims 1-4, characterized in that, Ar1 and Ar2 are each independently selected from any one of the following groups, either substituted or unsubstituted: ； Where —* represents the linking site of the group; Y1 is selected from O, S, NR 11 or CR 12 R 13 Any one of them; Y2 is selected from O or S; R 11 R 12 R 13 R 14 Each is independently selected from any one or a combination of at least two of the following: C1-C20 straight-chain or branched alkyl, C6-C30 aryl, C3-C30 heteroaryl, and C2-C20 alkenyl; The R 12 and R 13 They can be either not connected or linked together by chemical bonds to form a ring.

6. The electroluminescent material according to any one of claims 1-4, characterized in that, Ar1 and Ar2 are each independently selected from any one of the following unsubstituted or deuterated groups: ； In this context, —* represents the linking site of a functional group.

7. The electroluminescent material according to any one of claims 1-4, characterized in that, The R2 is selected from any one of deuterium, substituted or unsubstituted C1-C10 straight-chain or branched alkyl groups, substituted or unsubstituted C2-C10 alkenyl groups, substituted or unsubstituted C6-C20 aryl groups, and substituted or unsubstituted C3-C20 heteroaryl groups.

8. The electroluminescent material according to claim 1, characterized in that, The first organic material comprises any one or a combination of at least two of the following compounds: 。 9. The electroluminescent material according to claim 1, characterized in that, The second organic material has a structure as shown in any one of formulas II-1-1, II-1-2, II-1-3, II-2-1, II-2-2, and II-2-3: ； Ar3, Ar4 and L4 have the same defined range as in Formula II-1 or Formula II-2; R 61 R6' is independently selected from any one of the following groups, either substituted or unsubstituted: phenyl, biphenyl, terphenyl, naphthyl, naphthylphenyl, phenylnaphthyl, and binaphthyl; f1 is selected from 0 or 1.

10. The electroluminescent material according to claim 1 or 9, characterized in that, The Ar3 and Ar4 are each independently selected from any one of the following groups: ； Where —* represents the linking site of the group; Y3 is selected from CR 22 R 23 Any one of them; R 22 R 23 R 24 Each is independently selected from any one or a combination of at least two of C1-C20 straight-chain or branched alkyl groups and C6-C30 aryl groups; the R 22 and R 23 They can be either not connected or linked together by chemical bonds to form a ring.

11. The electroluminescent material according to claim 1 or 9, characterized in that, The Ar3 and Ar4 are each independently selected from any one of the following groups: ; where —* represents the linking site of the group.

12. The electroluminescent material according to claim 1, characterized in that, The second organic material comprises any one or a combination of at least two of the following compounds: 。 13. The electroluminescent material according to claim 1, characterized in that, The mass percentage of the first organic material in the electroluminescent material is 1-99%.

14. An application of the electroluminescent material as described in any one of claims 1-13, characterized in that, The electroluminescent material is used in organic electronic devices.

15. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes a first electrode, a second electrode, and an organic layer disposed between the first electrode and the second electrode, wherein the organic layer includes the electroluminescent material as described in any one of claims 1-13.

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