An electroluminescent material and an organic electroluminescent device comprising the same

Abstract

The application belongs to the technical field of organic electroluminescence, and specifically provides an electroluminescent material and an organic electroluminescent device comprising the same. The electroluminescent material comprises a combination of a first organic compound and a second organic compound, the first organic compound has a structure as shown in Formula I, and the second organic compound has a structure as shown in Formula II. Through structural design of the first organic compound and the second organic compound, especially introduction of a substituent group at a specific site, the two organic compounds are synergistically compounded, so that the material has a higher glass transition temperature Tg and excellent thermal stability while having excellent photoelectric performance and carrier transport performance. g The electroluminescent material is used in an organic electroluminescent device, especially in a light-emitting layer, can effectively ensure the uniformity of a deposited thin film, makes the thermal stability of the device excellent, and has a significantly improved high-temperature test life.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescence technology, specifically relating to an electroluminescent material and an organic electroluminescent device containing the same. Background Technology

[0002] In recent years, optoelectronic devices based on organic materials have become increasingly popular. The inherent flexibility of organic materials makes them ideal for fabrication on flexible substrates, allowing for the design and production of aesthetically pleasing and stylish optoelectronic products, offering unparalleled advantages over inorganic materials. Examples of such organic optoelectronic devices include organic light-emitting diodes (OLEDs), organic field-effect transistors, organic photovoltaic cells, and organic sensors; among them, OLEDs have developed particularly rapidly and have already achieved commercial success in the field of information display. OLEDs can provide highly saturated red, green, and blue colors, and full-color displays made with them do not require an additional backlight, offering advantages such as vibrant colors, thinness, and flexibility.

[0003] The core of an OLED device is a thin-film structure containing various organic functional materials. Common organic functional 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). When the device is powered on, electrons and holes are injected and transported to the light-emitting region, where they recombine, thereby generating excitons and emitting light.

[0004] Currently, various organic materials have been developed and combined with different device structures to improve carrier mobility, regulate carrier balance, break through electroluminescence efficiency, and delay device decay. According to the light-emitting mechanism, OLED devices can be mainly divided into fluorescence, phosphorescence, thermally excited delayed fluorescence, and thermally excited sensitized fluorescence. For quantum mechanical reasons, common fluorescent emitters mainly utilize 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, can simultaneously utilize triplet and singlet excitons to emit light, and are called phosphorescent emitters, whose energy conversion efficiency can be up to 4 times higher than that of traditional fluorescent emitters. Thermally excited delayed fluorescence (TADF) technology promotes the transition from triplet to singlet excitons, achieving high luminescence efficiency without the use of metal complexes, while still effectively utilizing triplet excitons. Thermally excited sensitized fluorescence (TASF) technology uses materials with TADF properties to sensitize the emitter through energy transfer, also achieving high luminescence efficiency.

[0005] As OLED products gradually enter the market, people have increasingly higher requirements for their performance. Current OLED materials and device structures cannot fully address issues related to efficiency, lifespan, cost, and thermal stability. Therefore, there is an urgent need in this field to develop more diverse and higher-performance organic materials to further improve the luminescent performance of devices. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide an electroluminescent material and an organic electroluminescent device comprising the same, wherein the glass transition temperature T of the electroluminescent material is synergistically increased through the structural design and mutual compounding of a first organic compound and a second organic compound. g It is used in organic electroluminescent devices, especially in the light-emitting layer, to give the device higher thermal stability and significantly improved high-temperature test life.

[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 compound and a second organic compound; the first organic compound having a structure as shown in Formula I:

[0009] Formula I.

[0010] In Equation I, Y is O or S.

[0011] In Formula I, L1 and L2 are each independently selected from any one of a single bond, a substituted or unsubstituted C6-C30 arylene, or a substituted or unsubstituted C3-C30 heteroarylene; when L1 is a single bond, it means that Ar1 and N atoms are directly connected by a single bond; when L2 is a single bond, it means that the dibenzo-p-5-membered ring structure is directly connected to N atoms by a single bond.

[0012] In Formula I, Ar1 is selected from any one of substituted or unsubstituted C6-C30 aryl groups or substituted or unsubstituted C3-C30 heteroaryl groups.

[0013] In Equation I, R1, R2, and Ar 21 Ar 22Each is independently selected from deuterium, halogen, cyano, substituted or unsubstituted C1-C30 straight-chain or branched alkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted tri(C1-C30 alkyl)silyl, substituted or unsubstituted di(C1-C30 alkyl)(C6-C30 aryl)silyl, substituted or unsubstituted tri(C6-C30 alkyl)di(C6-C30 aryl)silyl, substituted or unsubstituted tri(C6-C30 aryl)silyl, substituted or unsubstituted C1-C30 alkyl. The amino group, substituted or unsubstituted C2-C30 alkenylamino group, substituted or unsubstituted (C1-C30 alkyl)(C2-C30 alkenyl)amino group, substituted or unsubstituted C6-C30 arylamino group, substituted or unsubstituted (C1-C30 alkyl)(C6-C30 aryl)amino group, substituted or unsubstituted C3-C30 heteroarylamino group, substituted or unsubstituted (C1-C30 alkyl)(C3-C30 heteroaryl)amino group, substituted or unsubstituted (C2-C30 alkenyl)(C6-C30 aryl)amino group, substituted or unsubstituted (C2-C30 alkenyl)(C3-C30 heteroaryl)amino group, substituted or unsubstituted (C6-C30 aryl)(C3-C30 heteroaryl)amino group.

[0014] The R1, R2, Ar 21 Ar 22 At least two adjacent groups in the group are not connected or are linked by chemical bonds to form a ring.

[0015] In this invention, "R1, R2, Ar" 21 Ar 22 "At least two adjacent groups are not connected" means that the group is only connected to the C atom through a single bond; "R1, R2, Ar" 21 Ar 22 The phrase "at least two adjacent groups are linked by chemical bonds to form a ring" means that in addition to being chemically bonded to the carbon atom, adjacent groups are also chemically bonded together to form a fused ring structure. The same meaning applies to all instances of this description below, and will not be elaborated upon further.

[0016] In Formula I, n1, n2, m1, and m2 represent the substituent Ar, respectively. 21 Ar 22The number of integers R1, R2, and R2. n1 is selected from integers 0-3, for example, 0, 1, 2, or 3; n2 is selected from integers 0-4, for example, 0, 1, 2, 3, or 4; m1 is selected from integers 0-5, for example, 0, 1, 2, 3, 4, or 5; m2 is selected from integers 0-6, for example, 0, 1, 2, 3, 4, 5, or 6. And n1+n2+m1+m2≥1, for example, 1, 2, 3, 4, 5, 6, etc.

[0017] It should be noted that when n1≥2, multiple (at least 2) Ar 21 These can be the same or different groups. When n1 is 0, it indicates that there are no substituents on the corresponding benzene ring, and all three sites on the benzene ring are hydrogen atoms. The expressions for n2, m1, and m2 are similar, and for the sake of brevity, they will not be repeated. Similar descriptions in the following text have similar meanings.

[0018] The second organic compound has the structure shown in Formula II:

[0019] Formula II.

[0020] In Equation II, Z represents O or S.

[0021] In Equation II, L3, L4, L 51 L 52 Each is independently selected from any one of single-bonded, substituted or unsubstituted C6-C30 arylene, or substituted or unsubstituted C3-C30 heteroarylene; when L3 is a single bond, it means that Ar3 is directly connected to the triazine ring via a single bond; when L4 is a single bond, it means that Ar4 is directly connected to the naphthalene ring via a single bond; when L... 51 When it is a single bond, it represents Ar. 51 It is directly linked to the dibenzo-5-membered ring structure via a single bond; when the L 52 When it is a single bond, it represents Ar. 52 It is directly linked to the dibenzo5-membered ring structure via a single bond.

[0022] In Equation II, Ar3, Ar4, and Ar 51 Ar 52 Each is independently selected from any one of substituted or unsubstituted C6-C30 aryl groups or substituted or unsubstituted C3-C30 heteroaryl groups.

[0023] In Equation II, a1 and a2 are each independently 0 or 1, and a1 + a2 ≥ 1.

[0024] L1, L2, Ar1, R1, R2, Ar 21 Ar 22 L3, L4, L 51 L 52Ar3, Ar4, Ar 51 Ar 52 The substituents described herein are each independently selected from any one or a combination of at least two of the following: deuterium, halogen, cyano, C1-C30 straight-chain or branched alkyl, C6-C30 aryl, C3-C30 heteroaryl, C3-C30 cycloalkyl, C1-C30 alkoxy, C2-C30 alkenyl, C6-C30 arylamino, and C3-C30 heteroarylamino, and the substituents may optionally be substituted with deuterium.

[0025] 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 compound of Formula I and the second organic compound of Formula II is as shown above and will not be repeated.

[0026] In this invention, any hydrogen in the first organic compound may be optionally substituted with deuterium, and any hydrogen in the second organic compound may be optionally substituted with deuterium.

[0027] The electroluminescent material provided by this invention comprises a combination of a first organic compound and a second organic compound. The first organic compound, as shown in Formula I, has an aromatic amine structure, with a dibenzofuran / dibenzothiophene structure and a benzophenanthrene structure respectively attached to the aromatic amine, and each of the dibenzofuran / dibenzothiophene structure has at least one substituent (n1+n2+m1+m2≥1). The second organic compound, as shown in Formula II, contains a triazine structure with electron-withdrawing properties, with a dibenzofuran / dibenzothiophene structure and a naphthalene structure with specific substituents respectively attached to the triazine ring. This invention, through the structural design of two types of organic compounds, particularly by introducing substituents at specific fixed sites, achieves a synergistic combination, enabling the electroluminescent material to possess excellent photoelectric and carrier transport properties while also exhibiting a higher glass transition temperature T. g With excellent thermal stability, it can effectively ensure the uniformity of the deposited thin film when used in organic electroluminescent devices, which greatly reduces the device's lifespan degradation. It has excellent thermal stability and significantly improved high-temperature test life (referred to as "HTO life").

[0028] It should be noted that, for ease of explanation, the possible effects of each group / feature of the organic compound have been described separately in this invention, but this does not mean that these groups / features act in isolation. In fact, the reason for achieving good performance is essentially the optimized design of the entire molecular structure, the result of the synergistic effect between various groups, rather than the effect of a single group.

[0029] 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 objectives and beneficial effects of the present invention can be better achieved and realized.

[0030] In the present invention, for the expression 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.

[0031] In the present invention, the hydrogen at any site in the first organic compound can be optionally replaced by deuterium, and the hydrogen at any site in the second organic compound can be optionally replaced by deuterium.

[0032] In the present invention, the halogen can be fluorine, chlorine, bromine or iodine. The same description involved below has the same meaning.

[0033] 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 heterocycloalkyl are selected from N, O, S, P, B, Si or Se, preferably N, O or S.

[0034] In the present invention, the expression of the ring structure with a "-" drawn across it indicates that the connection site is at any position on the ring structure where bonding can occur.

[0035] In the present invention, " " and "*" both represent the connection sites of the group.

[0036] In the present invention, the expression Ca-Cb represents that the group has a carbon atom number of a-b. Unless otherwise specified, the carbon atom number does not include the carbon atom number of the substituent.

[0037] In the present invention, "independently of each other" means that when the subject has multiple ones, they can be the same or different from each other.

[0038] In the present invention, the C6-C30 can be C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26 or C28, etc.

[0039] The C3-C30 can be C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26 or C28, etc.

[0040] 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.

[0041] 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.

[0042] In this invention, the C6-C30 aryl group, preferably C6-C20 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 atomes are linked by a single bond, exemplarily 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, exemplarily including but not limited to: naphthyl (1-naphthyl, 2-naphthyl), anthraceneyl (1-anthrayl, 2-anthrayl, 9-anthrayl), phenanthrene, 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.

[0043] The C3-C30 heteroaryl group, preferably 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, exemplarily including but not limited to: quinolinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, benzofuranyl, benzothiopheneyl, isobenzofuranyl, isobenzothiopheneyl, indolyl, dibenzofuranyl, dibenzothiopheneyl, naphthobenzofuranyl, naphthobenzothiopheneyl, carbazoleyl and its derivatives ( N -Phenylacetazolyl, N -Naphthylcarbazolyl, benzocarbazolyl, dibenzocarbazolyl, indolocarbazolyl, azacarbazolyl, etc.), acridinel, phenothiazinyl, phenotoxazinyl, hydrogenated acridinel, etc. It should be noted that heteroaryl groups linked by single bonds, and aryl groups linked by single bonds, also fall under the category of heteroaryl groups, such as phenyldibenzofuranyl, phenyldibenzothiophenyl, dibenzothiophenylphenyl, dibenzofuranylphenyl, etc.

[0044] 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.

[0045] In this invention, a specific example of the C6-C30 arylamino group is a monovalent group obtained by substituting at least one (e.g., one or two) hydrogen atoms in the -NH2 group with the aforementioned aryl group. A specific example of the C3-C30 heteroarylamino group is a monovalent group obtained by substituting at least one (e.g., one or two) hydrogen atoms in the -NH2 group with the aforementioned heteroaryl group. A specific example of the (C6-C30 aryl)(C3-C30 heteroaryl)amino group is a monovalent group obtained by substituting one hydrogen atom in the -NH2 group with the aforementioned heteroaryl group and another hydrogen atom with the aforementioned aryl group.

[0046] 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.

[0047] Specific examples of the C1-C30 alkoxy groups can be exemplified by the monovalent groups obtained by connecting the above-mentioned straight-chain or branched alkyl groups with O.

[0048] A specific example of the C1-C30 alkylamino group is a monovalent group formed by replacing at least one (e.g., one or two) hydrogen atoms in -NH2 with the aforementioned straight-chain or branched alkyl groups.

[0049] The C2-C30 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.

[0050] Specific examples of the C2-C30 alkenylamino group are monovalent groups obtained by substituting at least one (e.g., one or two) hydrogen atoms in the -NH2 group with the alkenyl group described above. Specific examples of the (C1-C30 alkyl)(C2-C30 alkenyl)amino group are monovalent groups obtained by substituting one hydrogen atom in the -NH2 group with the alkenyl group and another hydrogen atom with the straight-chain or branched alkyl group described above. Specific examples of the (C1-C30 alkyl)(C6-C30 aryl)amino group are monovalent groups obtained by substituting one hydrogen atom in the -NH2 group with the aryl group and another hydrogen atom with the straight-chain or branched alkyl group described above. Specific examples of the (C1-C30 alkyl)(C3-C30 heteroaryl)amino group are monovalent groups obtained by substituting one hydrogen atom in the -NH2 group with the heteroaryl group and another hydrogen atom with the straight-chain or branched alkyl group described above. A specific example of the (C2-C30 alkenyl)(C6-C30 aryl)amino group is a monovalent group obtained by substituting one hydrogen atom in -NH2 with the aforementioned aryl group and one hydrogen atom with the aforementioned alkenyl group. A specific example of the (C2-C30 alkenyl)(C3-C30 heteroaryl)amino group is a monovalent group obtained by substituting one hydrogen atom in -NH2 with the aforementioned heteroaryl group and one hydrogen atom with the aforementioned alkenyl group.

[0051] The C3-C30 cycloalkyl group, preferably C3-C10 cycloalkyl group, includes monocycloalkyl or polycycloalkyl groups. 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.

[0052] Specific examples of the C2-C30 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.

[0053] Specific examples of the tri(C1-C30 alkyl)silyl group are monovalent groups formed by the independent substitution of each of the three hydrogens in -SiH3 with the aforementioned straight-chain or branched alkyl groups. Specific examples of the di(C1-C30 alkyl)(C6-C30 aryl)silyl group are monovalent groups formed by the independent substitution of each of the two hydrogens in -SiH3 with the aforementioned straight-chain or branched alkyl groups and the substitution of one hydrogen with the aforementioned aryl group. Specific examples of the (C1-C30 alkyl)di(C6-C30 aryl)silyl group are monovalent groups formed by the independent substitution of each of the two hydrogens in -SiH3 with the aforementioned aryl group and the substitution of one hydrogen with the aforementioned straight-chain or branched alkyl group. Specific examples of the tri(C6-C30 aryl)silyl group are monovalent groups formed by the independent substitution of each of the three hydrogens in -SiH3 with the aforementioned aryl group.

[0054] As a preferred embodiment of the present invention, the first organic compound has a structure as shown in any one of formulas IA to IE:

[0055] ;

[0056] Among them, Y, L1, L2, Ar1, R1, R2, Ar 21 Ar 22 n1, n2, m1 and m2 have the same range of limitation as in Equation I.

[0057] As a preferred embodiment of the present invention, in formula I, 1≤n1+n2+m1+m2≤2. Preferably, 0≤n1+n2≤1, 0≤m1+m2≤1, and n1+n2+m1+m2≥1.

[0058] As a preferred embodiment of the present invention, the first organic compound has any of the following structures:

[0059] ;

[0060] Among them, Y, L1, L2, Ar1, R1, R2, Ar 21 Ar 22 n1 and n2 have the same range of limitation as in Equation I.

[0061] n3 is selected from integers from 0 to 3, for example, it can be 0, 1, 2 or 3; n4 is selected from integers from 0 to 4, for example, it can be 0, 1, 2, 3 or 4; and n3+n4≥1, for example, it can be 1, 2, 3, 4, 5, 6, etc., preferably n3+n4=1.

[0062] As another preferred embodiment of the present invention, the first organic compound has a structure as shown in formula IF or formula IG:

[0063] ;

[0064] Among them, Y, L1, L2, Ar1, Ar 21 and Ar 22 It has the same defined range as in Equation I.

[0065] Preferably, L1 and L2 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.

[0066] As a preferred embodiment of the present invention, L1 and L2 are each independently selected from any one of the following groups: single bond, substituted or unsubstituted:

[0067] ;

[0068] in, The linking site of the representative group.

[0069] As a preferred embodiment of the present invention, the Ar1 is selected from any one of the following groups, whether substituted or unsubstituted:

[0070] ;

[0071] in, The linking site of the representative group.

[0072] X1 is selected from O, S, NR 11 or CR 12 R 13 Any one of them.

[0073] R 11 R 12 R 13 Each group is independently selected from any one or a combination of at least two of the following unsubstituted or deuterated groups: C1-C30 straight-chain or branched alkyl, C6-C30 aryl, C3-C30 heteroaryl, C2-C30 alkenyl; The R 12 and R 13 They can be either not connected or linked together by chemical bonds to form a ring.

[0074] Preferably, the R 11 R 12 R 13 Each group is independently selected from any one or at least two combinations of the following unsubstituted or deuterated groups: C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) straight-chain or branched alkyl, C2-C10 (e.g., C3, C4, C5, C6, C7, C8, C9, etc.) alkenyl, C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl, and more preferably any one of the following unsubstituted or deuterated groups: C1-C6 straight-chain or branched alkyl, phenyl, naphthyl, biphenyl, terphenyl, phenylnaphthyl, naphthylphenyl, and more preferably unsubstituted or deuterated methyl or unsubstituted or deuterated phenyl.

[0075] Preferably, the R 12 and R 13 They can form spirofluorene groups either without bonding or by chemical bonds.

[0076] As a preferred embodiment of the present invention, the Ar1 is selected from any one of the following unsubstituted or deuterated groups:

[0077] ;

[0078] in, The linking site of the representative group.

[0079] As a preferred technical solution of the present invention, R1, R2, Ar 21 Ar22 Each group is independently selected from any one of the following groups, whether substituted or unsubstituted:

[0080] ;

[0081] in, The linking site of the representative group.

[0082] As a preferred technical solution of the present invention, the Ar 21 Ar 22 The ring Cy is formed by any two adjacent groups that are not connected or are linked by chemical bonds. The ring Cy is selected from any one of the following: substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, C18, etc.) alicyclic rings, substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, C18, etc.) aromatic rings, and substituted or unsubstituted C3-C20 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C15, C16, C18, etc.) heteroaromatic rings, preferably benzene rings or naphthalene rings.

[0083] Preferably, the Ar 22 In benzene, any two adjacent groups are not connected, or are connected by chemical bonds to form a benzene ring (e.g., forming a benzene ring). Any one of the following), or linked by chemical bonds to form a naphthalene ring (for example, forming any one of the following structures: );in, The connection site between the representative group and L2.

[0084] As a preferred embodiment of the present invention, the first organic compound has a structure shown in any of the following:

[0085] .

[0086] 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. Taking H136 as an example, "D1-29" means that 1-29 H atoms in the molecular structure are replaced by D atoms. Other similar expressions in this article are similar and will not be repeated one by one.

[0087] As a preferred technical solution of the present invention, in formula II, a1+a2=1.

[0088] As a preferred embodiment of the present invention, the second organic compound has a structure as shown in any one of formulas II-1 to II-5:

[0089] ;

[0090] Among them, Z, L3, L4, L 51 L 52 Ar3, Ar4, Ar 51 and Ar 52 It has the same limiting range as in Formula II.

[0091] Preferably, L3, L4, L 51 L 52 Each is 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, or substituted or unsubstituted C5-C20 (e.g., C6, C7, C8, C9, C10, C12, C14, C15, C16 or C18, etc.) heteroaryl.

[0092] As a preferred technical solution of the present invention, L3, L4, L 51 L 52 Each group is independently selected from any one of the following groups: single bond, substituted or unsubstituted:

[0093] ;

[0094] in, The linking site of the representative group.

[0095] As a preferred technical solution of the present invention, the Ar3, Ar4, and Ar 51 Ar 52 Each group is independently selected from any one of the following groups, whether substituted or unsubstituted:

[0096] ;

[0097] in, The linking site of the representative group.

[0098] As a preferred embodiment of the present invention, the second organic compound has a structure shown in any of the following:

[0099] .

[0100] As a preferred embodiment of the present invention, the mass ratio of the first organic compound to the second organic compound is (0.1-2):1, for example, it can be 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, etc., and is further preferably (0.8-1.5):1.

[0101] 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.

[0102] 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.

[0103] Preferably, the electroluminescent material is used in an organic electroluminescent device.

[0104] Preferably, the electroluminescent material is used as the light-emitting layer material in an organic electroluminescent device.

[0105] Preferably, the electroluminescent material serves as the host material for the light-emitting layer in an organic electroluminescent device.

[0106] 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.

[0107] Preferably, the organic layer includes a light-emitting layer, wherein the light-emitting layer includes an electroluminescent material as described in the first aspect.

[0108] 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.

[0109] Preferably, the electroluminescent material is used as the main material of the light-emitting layer.

[0110] Preferably, the light-emitting layer further includes a dopant material.

[0111] In this invention, the term "doped material" is also known as "dye", "luminescent dye", or "guest material".

[0112] Preferably, the doping material is a phosphorescent doping material.

[0113] Preferably, the emission wavelength of the doped material is 500-650 nm, for example, it can be 510 nm, 520 nm, 530 nm, 540 nm, 550 nm, 560 nm, 580 nm, 600 nm, 620 nm or 640 nm, and more preferably 500-550 nm.

[0114] Preferably, based on the mass of the electroluminescent material as 100%, the mass of the doped material is 0.1-15%, for example, it can be 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12% or 14%, etc.

[0115] Preferably, the light-emitting layer is prepared by vacuum thermal evaporation.

[0116] Preferably, the vacuum thermal evaporation method includes: premixing a first organic compound and a second organic compound to obtain the electroluminescent material; and evaporating the electroluminescent material and the doped material using a dual-source co-evaporation method to obtain the luminescent layer.

[0117] As a preferred technical solution of the present invention, the first organic compound and the second organic compound are premixed and then vapor-deposited, which has excellent vapor deposition stability, ensuring that the proportion of the main material changes little during the continuous vapor deposition process, thereby ensuring the stability of device performance and further improving the performance consistency in device fabrication.

[0118] Preferably, the organic layer further includes a hole transport region and an electron transport region.

[0119] 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.

[0120] 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.

[0121] 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.

[0122] 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) comprises the electroluminescent material provided by this invention.

[0123] 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).

[0124] The first electrode can be formed by sputtering or depositing the material to be used as the first electrode on a substrate. When the first electrode is used as the anode, transparent conductive oxide materials such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), and zinc oxide (ZnO) and any combination thereof can be used. When the first electrode is used as the cathode, metals or alloys such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), ytterbium (Yb), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag) and any combination thereof can be used.

[0125] 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.

[0126] 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.

[0127] 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.

[0128] .

[0129] 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.

[0130]

[0131] 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.

[0132] Depending on the technology used, the light-emitting layer material can be phosphorescent photoluminescent material. An OLED device can employ a single light-emitting technology or a combination of different light-emitting technologies. These different light-emitting materials, categorized by technology, can emit light of the same color or different colors.

[0133] In a preferred embodiment of the present invention, the material of the light-emitting layer is a phosphorescent host material, which is an electroluminescent material provided by the present invention, comprising a combination of a first organic compound (structure shown in Formula I) and a second organic compound (structure shown in Formula II). The emission wavelength of the phosphorescent doped material is 500-650 nm, preferably 500-550 nm.

[0134] 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 GPD-1 to GPD-60 listed below.

[0135]

[0136] Where D represents deuterium.

[0137] 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.

[0138] .

[0139] 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 YPD-1 to YPD-11 listed below.

[0140] .

[0141] 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.

[0142] 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.

[0143] .

[0144] 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.

[0145] 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.

[0146] Fourthly, the present invention provides a display device comprising the organic electroluminescent device as described in the third aspect.

[0147] Preferably, the display device includes a display screen or a display panel.

[0148] The present invention also provides an electronic device, which includes the aforementioned display device.

[0149] Compared with the prior art, the present invention has at least the following beneficial effects:

[0150] The electroluminescent material provided by this invention, through the structural design of the first and second organic compounds, especially the introduction of substituent groups at specific sites, allows the two organic compounds to synergistically combine, enabling the material to possess both excellent photoelectric properties and carrier transport performance, while also exhibiting a higher glass transition temperature T. g It exhibits excellent thermal stability. The electroluminescent material is used in organic electroluminescent devices, especially in the light-emitting layer, effectively ensuring the uniformity of the deposited thin film, resulting in excellent thermal stability and significantly improved high-temperature test life. Attached Figure Description

[0151] Figure 1 This is a schematic diagram of the structure of an organic electroluminescent device provided in a specific embodiment of the present invention;

[0152] Among them, 1-substrate, 2-anode, 3-hole injection layer, 4-hole transport layer, 5-electron blocking layer, 6-light emitting layer, 7-hole blocking layer, 8-electron transport layer, 9-electron injection layer, 10-cathode, 11-external power supply. Detailed Implementation

[0153] To facilitate understanding of the present invention, specific embodiments are provided to further illustrate the technical solution of the present invention. Those skilled in the art should understand that the embodiments are merely illustrative of the present invention and should not be considered as specific limitations thereof.

[0154] In one specific embodiment, the first organic compound and the second organic compound can be prepared by methods disclosed in the prior art (e.g., CN11647441A, CN120717984A, CN108368078A, etc.).

[0155] In another specific embodiment, the first organic compound can be prepared via the following exemplary synthetic route:

[0156]

[0157] Among them, Y, L1, L2, Ar1, R1, R2, Ar 21 Ar 22 n1, n2, m1 and m2 have the same definitions as in Formula I; Hal1 is selected from any of the halogens, such as F, I, Br or Cl, preferably Cl or Br.

[0158] The preparation method of intermediate M will be described in detail below using several synthetic examples, but the preparation of intermediate M is not limited to these synthetic examples.

[0159] The mass spectrometry (MS, m / z) characterization data of the intermediates and target products in the following specific embodiments of the present invention were obtained by liquid chromatography-mass spectrometry (LC-MS / Q-TOF, Agilent, ion source: ESI+APCI), specifically M+H. For the identification of compounds with the same molecular weight but different substitution sites, the correctness of the structure can be confirmed by referring to the peak times of high performance liquid chromatography (HPLC) and information such as the different raw materials used.

[0160] Example 1 of intermediate synthesis

[0161]

[0162] 0.1 mol of phenylboronic acid, 0.1 mol of 1-chloro-4-bromonaphthalene, 0.12 mol of potassium carbonate, 0.001 mol of tetra(triphenylphosphine)palladium, 30 mL of water, and 300 mL of dioxane were added to a reaction flask and heated to 70 °C for 4 h. The reaction was monitored by thin-layer chromatography (TLC) until complete. The mixture was extracted with water and dichloromethane, and the organic phase was separated, concentrated, washed with ethanol, and filtered to obtain intermediate M1-A.

[0163] The starting material M1-A (0.095 mol), pinacol diboronate (0.1 mol), potassium acetate (0.01 mol), tris(dibenzylacetone)dipalladium (0.0001 mol), 2-dicyclohexylphosphine-2',6'-dimethoxy-biphenyl (0.0002 mol), and dioxane (150 mL) were added to a reaction flask and heated to 100 °C for 5 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction, and the organic phase was separated and concentrated to obtain intermediate M1-B.

[0164] M1-B (0.08 mol), 5-chloro-2-aldehyde phenylboronic acid (0.08 mol), potassium carbonate (0.1 mol), tetra(triphenylphosphine)palladium (0.0008 mol), water (20 mL), and dioxane (200 mL) were added to a reaction flask and heated to 100 °C for 6 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction, and the organic phase was separated and concentrated to obtain intermediate M1-C.

[0165] M1-C (0.05 mol), (methoxymethyl)triphenylphosphine chloride (0.07 mol), and tetrahydrofuran (100 mL) were added to a reaction flask, stirred, and cooled to 0°C. Sodium tert-butoxide (0.1 mol) was slowly added, and the reaction was maintained at this temperature for 2 h after 30 min. The temperature was then slowly increased to room temperature for 2 h, and the reaction was monitored by TLC until complete. The mixture was extracted with brine and ethyl acetate, and the organic phase was concentrated to obtain intermediate M1-D.

[0166] M1-D (0.05 mol) and dichloromethane (200 mL) were added to a reaction flask, stirred, and cooled to -10°C. Methanesulfonic acid (0.15 mol) was added dropwise, and the reaction was maintained at this temperature for 1 h. The temperature was then slowly increased to room temperature for 3 h, and the reaction was monitored by TLC until complete. The reaction solution was added to 200 mL of water and stirred. The organic phase was separated, concentrated, washed with ethanol, and filtered to obtain intermediate M1 (MS theoretical value: 338.09, measured value: 339.112).

[0167] Using the same process route as in Intermediate Synthesis Example 1, but replacing 1-chloro-4-bromonaphthalene with equimolar amounts of different halonaphthalene feedstocks, the intermediates shown in Table 1 can be obtained:

[0168] Table 1

[0169]

[0170] Example 2 of intermediate synthesis

[0171]

[0172] 2,4-Dichloro-6-bromobenzaldehyde (0.2 mol), phenylboronic acid (0.2 mol), potassium carbonate (0.22 mol), tetra(triphenylphosphine)palladium (0.002 mol), water (50 mL), and dioxane (500 mL) were added to a reaction flask and heated to 60 °C for 4 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction, and the organic phase was separated and concentrated to obtain intermediate M6-A.

[0173] M6-A (0.13 mol), phenylboronic acid (0.13 mol), potassium carbonate (0.15 mol), tetra(triphenylphosphine)palladium (0.0013 mol), water (40 mL), and dioxane (400 mL) were added to a reaction flask and heated to 90 °C for 10 h. The reaction was monitored by TLC until complete. Water and dichloromethane were added for extraction, and the organic phase was separated and concentrated to obtain intermediate M6-B.

[0174] M6-B (0.1 mol), (methoxymethyl)triphenylphosphine chloride (0.15 mol), and tetrahydrofuran (300 mL) were added to a reaction flask, stirred, and cooled to 0°C. Sodium tert-butoxide (0.2 mol) was slowly added, and the reaction was maintained at this temperature for 2 h after 30 min. The temperature was then slowly increased to room temperature for 2 h, and the reaction was monitored by TLC until complete. The mixture was extracted with brine and ethyl acetate, and the organic phase was concentrated to obtain intermediate M6-C.

[0175] M6-C (0.05 mol) and dichloromethane (200 mL) were added to a reaction flask, stirred, and cooled to -10 °C. Methanesulfonic acid (0.15 mol) was added dropwise, and the reaction was maintained at this temperature for 1 h. The temperature was then slowly increased to room temperature for 3 h, and the reaction was monitored by TLC until complete. The reaction solution was added to 200 mL of water and stirred. The organic phase was separated, concentrated, washed with ethanol, and filtered to obtain intermediate M6 (MS theoretical value: 338.09, measured value: 339.101).

[0176] The above lists the methods for synthesizing some intermediates with benzene ring substitution. In this invention, other intermediates involved in the first organic compound with the structure shown in Formula I can be prepared by replacing phenylboronic acid or halonaphthalene raw materials with the corresponding raw materials and using the same process route as described above, and will not be described in detail here.

[0177] The specific preparation method of the first organic compound of the present invention will be described in detail below using synthetic examples, but the preparation method of the present invention is not limited to these synthetic examples.

[0178] Synthesis example 1

[0179]

[0180] Intermediate M1 (0.01 mol), S1 (0.01 mol), sodium tert-butoxide (0.012 mol), tris(dibenzylacetone)palladium (0.0001 mol), tri-tert-butylphosphine (0.0002 mol), and toluene (100 mL) were added to a reaction flask and heated to reflux for 5 h. The reaction was monitored by TLC until complete. The reaction solution was directly filtered through 100-200 mesh silica gel for rapid filtration. The filtrate was concentrated and recrystallized from toluene and ethanol to obtain the target product E5 (MS theoretical value: 637.24, measured value: 638.238).

[0181] Following the same process route as in Synthesis Example 1, only by replacing intermediate M1 with other intermediates in Table 1, we can obtain the first compounds D5, F5, G5, and H5.

[0182] Synthesis example 2

[0183]

[0184] E5 (0.01 mol), per-deuterated benzene (benzene-d6, 0.8 mol), and trifluoromethanesulfonic acid (0.1 mol) were added to a reaction flask and heated to 70 °C for 16 h. The reaction was stopped when the molecular weight was monitored by liquid chromatography-mass spectrometry (LC-MS) to be 656.351. After cooling, an aqueous solution of potassium phosphate was added to the reaction solution to adjust the pH to neutral. The organic phase was separated and concentrated to obtain E131-D18.

[0185] It should be noted that D1-31 in the upper right corner of the square brackets of compound E131 indicates that the number of deuterated atoms can be 1-31. Synthesis Example 2 provides an exemplary process route for deuterated atoms with 18 hydrogen atoms. To obtain different proportions of deuterated atoms, it is only necessary to control benzene-d6, trifluoromethanesulfonic acid, and reaction time, which will not be elaborated further.

[0186] In another specific embodiment, the second organic compound can be prepared via the following exemplary synthetic route:

[0187] Among them, Z, L3, L4, L 51 L 52 Ar3, Ar4, Ar 51 Ar 52a1 and a2 have the same definitions as in Formula II; Hal2 and Hal3 are each independently selected from any of the halogens, for example, F, I, Br, or Cl, preferably Cl or Br. U1 and U2 are each independently selected from any of the following groups: Coupling reactions I and II are Suzuki reactions. The specific order can be adjusted according to the actual situation. That is, coupling reaction I can be carried out first, followed by coupling reaction II, or coupling reaction II can be carried out first, followed by coupling reaction I.

[0188] In one specific implementation, Hal2 and Hal3 are Cl, and U1 is... U2 is First, perform coupling reaction I, then perform coupling reaction II.

[0189] 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.

[0190] Example 1

[0191] An electroluminescent material comprising a first organic compound J151 and a second organic compound N156, wherein the mass ratio of J151 to N156 is 1:1.

[0192] An organic electroluminescent device, comprising the electroluminescent material provided in this embodiment, is shown in the schematic diagram of the device structure as follows. Figure 1 As shown, the substrate includes a substrate 1 (glass substrate), an anode 2 (ITO), a hole injection layer 3, a hole transport layer 4, an electron blocking layer 5, a light-emitting layer 6, a hole blocking layer 7, an electron transport layer 8, an electron injection layer 9, and a cathode 10 (Al) stacked in sequence; an external power supply 11 is applied between the anode 2 and the cathode 10.

[0193] The method for fabricating the organic electroluminescent device is as follows:

[0194] (1) The glass substrate coated with ITO transparent conductive layer was ultrasonically treated in commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone / ethanol, baked in a clean environment until the moisture was completely removed, cleaned with ultraviolet light and ozone, and bombarded with low-energy cation beam.

[0195] (2) Place the glass substrate with the anode in the vacuum chamber and evacuate it to <1×10 -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, and the thickness of the deposited film was 10 nm.

[0196] (3) A 100 nm layer of compound HT-29 was vacuum-deposited on the hole injection layer as a hole transport layer;

[0197] (4) A 35 nm layer of compound HT-41 was vacuum-deposited on the hole transport layer as an electron blocking layer;

[0198] (5) A light-emitting layer of the device is vacuum-deposited on an electron blocking layer. The light-emitting layer comprises a mixture of a host material (the electroluminescent material, J151:N156=1:1) and a dopant material (dye, RPD-19). The mass ratio (w / w) of the host material and the dopant material is 100:2. The device is deposited using a dual-source co-evaporation method. The evaporation rate of the first organic compound is 0.1 nm / s, the evaporation rate of the second organic compound is 0.1 nm / s, the evaporation rate of RPD-19 is 0.002 nm / s, and the total film thickness is 40 nm.

[0199] (6) A 5 nm layer of compound ET-17 was vacuum-deposited on the light-emitting layer as a hole blocking layer for the device;

[0200] (7) A mixture of compounds ET-66:ET-57 (50 / 50, w / w) was vacuum-deposited on the hole blocking layer as an electron transport layer with a film thickness of 25 nm.

[0201] (8) A 1 nm thick LiF layer was vacuum-deposited on the electron transport layer as an electron injection layer;

[0202] (9) A 150 nm thick layer of aluminum is vacuum-deposited on the electron injection layer as a cathode; the total deposition rate of all organic layers and LiF is controlled at 0.1 nm / s, and the deposition rate of the metal electrode is 1 nm / s; thus, the organic electroluminescent device is obtained.

[0203] Examples 2-95, Comparative Examples 1-2

[0204] An electroluminescent material and an organic electroluminescent device comprising the same are disclosed. The only difference between the electroluminescent material (the main material of the light-emitting layer) and Example 1 is that the electroluminescent material (the main material of the light-emitting layer) is replaced with the compounds in Table 2. The other structures, materials and preparation methods of the device are the same as those in Example 1. The "mass ratio" in Table 2 represents the mass ratio of the first organic compound to the second organic compound.

[0205] The structure of the main material in the comparative example is as follows:

[0206]

[0207] Device performance testing:

[0208] HTO test: 50 mA / cm at the same current density 2The device under test was placed in an 85℃ constant temperature chamber, and the brightness of the organic electroluminescent device was measured using a luminance meter. The brightness decay rate was observed after 240 hours of continuous testing. The initial brightness was recorded as 100%. 240 This represents the ratio of brightness after 240 hours to initial brightness. A larger ratio indicates less brightness decay and better lifespan performance of HTO.

[0209] T g Test: A Shimadzu DSC-60Plus differential scanning calorimeter was used. 3-5 mg of sample was weighed into the DSC crucible, and the crucible lid was placed on the sample press. The sample crucible was then placed inside the instrument. The initial temperature was set to 60℃, the heating rate to 20℃ / min, and the final temperature to 400℃. After the first test, the instrument temperature was allowed to drop below 60℃ before the second test. After the first test, the data analysis software was opened, the second test data was accessed, the DSC curve was selected, and the glass transition temperature processing option was selected. Temperature points were selected on both sides of the peak of the test curve for analysis. The analysis software provided the midpoint temperature, which is the glass transition temperature T. g .

[0210] The test data is shown in Table 2:

[0211] Table 2

[0212]

[0213] In Table 2, "-Dn" indicates that n hydrogens in the compound are replaced by deuterium; for example, A132-D15 means that 15 hydrogens in A132 are replaced by deuterium.

[0214] As can be seen from the performance data in Table 2, the electroluminescent material provided by this invention, through the structural design of the first and second organic compounds, especially the introduction of substituent groups into specific groups, enables the two materials to synergistically combine, thereby effectively improving the molecular TL. g Temperature, causing T g ≥121℃, reaching 121-142℃, thus making it more difficult for molecules to deform due to temperature changes during HTO lifetime testing of devices. This effectively ensures the uniformity of the deposited film, significantly reducing the device's lifetime degradation. 240 >96.8%, significantly improving HTO lifespan.

[0215] The present invention has been illustrated through the above embodiments, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, additions of auxiliary components, and 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 compound and a second organic compound; The first organic compound has the structure shown in Formula I: Equation I; Where Y is O or S; L1 and L2 are each independently selected from any one of the single-bonded, substituted or unsubstituted C6-C12 aryl groups; Ar1 is selected from any one of substituted or unsubstituted C6-C20 aryl groups and substituted or unsubstituted C3-C20 heteroaryl groups; R1, R2, Ar 21 Ar 22 Each is independently selected from any one of substituted or unsubstituted C6-C20 aryl, substituted or unsubstituted C3-C20 heteroaryl, or substituted or unsubstituted C2-C10 alkenyl; The Ar 22 At least two adjacent groups in the group are not connected or are linked by chemical bonds to form a ring; n1 is 0 or 1, n2 is an integer selected from 0 to 2, m1 is 0 or 1, m2 is 0 or 1, and n1+n2+m1+m2≥1; The second organic compound has the structure shown in Formula II: Formula II; Where Z represents O or S; L3, L4, L 51 L 52 Each is independently selected from any one of the single-bonded, substituted or unsubstituted C6-C12 arylene groups; Ar3, Ar4, Ar 51 Ar 52 Each is independently selected from any one of the substituted or unsubstituted C6-C20 aryl groups; a1 and a2 are each independently 0 or 1, and a1 + a2 ≥ 1; L1, L2, Ar1, R1, R2, Ar 21 Ar 22 L3, L4, L 51 L 52 Ar3, Ar4, Ar 51 Ar 52 The substituents described herein are each independently selected from any one or a combination of at least two of deuterium, halogen, cyano, C1-C10 straight-chain or branched alkyl, C6-C20 aryl, C3-C20 heteroaryl, and C2-C10 alkenyl, and the substituents may optionally be substituted with deuterium; In the first organic compound, any hydrogen may be optionally substituted with deuterium, and in the second organic compound, any hydrogen may be optionally substituted with deuterium.

2. The electroluminescent material according to claim 1, characterized in that, The first organic compound has a structure as shown in any one of formulas IA to IE: ； Among them, Y, L1, L2, Ar1, R1, R2, Ar 21 Ar 22 n1, n2, m1 and m2 have the same range of limitation as in Equation I.

3. The electroluminescent material according to claim 1, characterized in that, The first organic compound has any of the following structures: ； Among them, Y, L1, L2, Ar1, R1, R2, Ar 21 Ar 22 n1 and n2 have the same defined range as in Equation I; n3 is 0 or 1, n4 is selected from integers from 0 to 2, and n3 + n4 ≥ 1.

4. The electroluminescent material according to claim 1, characterized in that, The first organic compound has a structure as shown in formula IF or formula IG: ； Among them, Y, L1, L2, Ar1, Ar 21 and Ar 22 It has the same defined range as in Equation I.

5. The electroluminescent material according to any one of claims 1-4, characterized in that, L1 and L2 are each independently selected from any one of the following groups: single bond, substituted or unsubstituted: ； in, The linking site of the representative group.

6. The electroluminescent material according to any one of claims 1-4, characterized in that, The Ar1 is selected from any one of the following groups, whether substituted or unsubstituted: ； in, The linking site of the representative group; X1 is selected from O, S, NR 11 or CR 12 R 13 Any one of them; R 11 R 12 R 13 Each group is independently selected from any one or a combination of at least two of the following unsubstituted or deuterated groups: C1-C10 straight-chain or branched alkyl, C6-C20 aryl, C2-C10 alkenyl; The R 12 and R 13 They can be either not connected or linked together by chemical bonds to form a ring.

7. The electroluminescent material according to claim 6, characterized in that, The Ar1 is selected from any one of the following groups, either unsubstituted or deuterated: ； in, The linking site of the representative group.

8. The electroluminescent material according to any one of claims 1-4, characterized in that, The R1, R2, Ar 21 Ar 22 Each group is independently selected from any one of the following groups, whether substituted or unsubstituted: ； in, The linking site of the representative group; And / or, the Ar 22 The at least two adjacent groups are not connected or are connected by chemical bonds to form a ring Cy, wherein the ring Cy is a benzene ring or a naphthalene ring.

9. The electroluminescent material according to claim 1, characterized in that, The first organic compound has a structure shown in any of the following: 。 10. The electroluminescent material according to claim 1, characterized in that, The second organic compound has a structure as shown in any one of formulas II-1 to II-5: ； Among them, Z, L3, L4, L 51 L 52 Ar3, Ar4, Ar 51 and Ar 52 It has the same limiting range as in Formula II.

11. The electroluminescent material according to claim 1 or 10, characterized in that, The L3, L4, L 51 L 52 Each group is independently selected from any one of the following groups: single bond, substituted or unsubstituted: ； in, The linking site of the representative group.

12. The electroluminescent material according to claim 1 or 10, characterized in that, The Ar3, Ar4, Ar 51 Ar 52 Each group is independently selected from any one of the following groups, whether substituted or unsubstituted: ； in, The linking site of the representative group.

13. The electroluminescent material according to claim 1, characterized in that, The second organic compound has a structure shown in any of the following: 。 14. The electroluminescent material according to claim 1, characterized in that, The mass ratio of the first organic compound to the second organic compound is (0.1-2):

1.

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

16. 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 1-14.

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