An organic electroluminescent device

Abstract

The present application belongs to the technical field of organic electroluminescence, and particularly relates to an organic electroluminescence device. The organic electroluminescence device provided by the present application comprises a hole transport region including one or more than one hole transport layer (one, two or three layers) and a light-emitting auxiliary layer, wherein the hole transport layer contains a compound represented by formula (I), the light-emitting auxiliary layer contains a compound represented by formula (II), and when the hole transport region contains multiple layers of hole transport layers (two or three layers), the compounds in each layer of hole transport layer are different. The hole transport region with the above layer structure can make the device have appropriate hole transport capacity and exciton blocking capacity, and can well match each organic functional layer, so that the performance of driving voltage, light-emitting efficiency and service life is well improved.

Description

Technical Field

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

[0002] Organic light-emitting diodes (OLEDs) have the characteristics of being thin and light, having a wide viewing angle, fast response speed, wide operating temperature range, low energy consumption, high efficiency, good color purity, high definition, and good flexibility. They have been widely used in the fields of lighting and display and are considered by the industry to be one of the most promising display and lighting technologies.

[0003] Classic OLED devices have a "sandwich" structure, with an emissive layer sandwiched between two electrodes: a cathode and an anode. This emissive layer contains a luminescent material (guest material). When a specific operating voltage is applied between the two electrodes, holes and electrons are injected from the anode and cathode, respectively, and then reach the emissive layer. There, they recombine to generate excitons, releasing energy. Under the influence of an electric field, the excitons migrate, transferring energy to the luminescent material. Electrons in the luminescent material molecules transition from the ground state to an excited state. Since the excited state is unstable, the electrons then migrate back to the ground state, releasing energy as light, thus producing the luminescence phenomenon. To improve the device's performance in terms of driving voltage, luminous efficiency, color purity, clarity, and lifespan, a hole transport region is typically placed between the anode and the emissive layer, and an electron transport region is placed between the cathode and the emissive layer. The hole transport region primarily functions to inject and transport holes and can include one or more of the following: a hole injection layer, a hole transport layer, an emissive auxiliary layer, and an electron blocking layer. The electron transport region primarily functions to inject and transport electrons and can include one or more of the following: an electron injection layer, an electron transport layer, and a hole blocking layer. Simultaneously, it requires excellent energy level matching between the organic layers in the two charge transport regions and with other functional organic layers (such as the light-emitting layer). This prevents excitons from diffusing to the edge of the light-emitting layer, maintaining a high ratio of effective light emission within the light-emitting layer. This not only improves the device's luminous efficiency but also reduces the heat generated by interfacial luminescence, preventing rapid aging of organic materials and extending the device's lifespan. In addition to placing an organic functional layer between the anode and cathode, a capping layer with high refractive index and high transmittance is also placed on the outer side of the light-emitting electrode (e.g., the outer side of the cathode in a top-emitting device) to improve the device's luminous efficiency and color purity.

[0004] Currently, most OLED devices used in the industry suffer from a mismatch between the transport rates of holes and electrons, which leads to a decline in the device's driving voltage, luminous efficiency, and lifespan. Therefore, OLED researchers need to continuously optimize and innovate in the selection of OLED materials and the structure of OLED devices. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an organic electroluminescent device, comprising an anode, a cathode, and an organic layer. The organic layer is located between the anode and the cathode. The organic layer includes a hole transport region, a light-emitting layer, and an electron transport region. The hole transport region includes a first hole transport layer and a light-emitting auxiliary layer. The first hole transport layer is located between the anode and the light-emitting layer, and the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer. The first hole transport layer contains one of the compounds shown in formula (I), and the light-emitting auxiliary layer contains one of the compounds shown in formula (II). The organic functional layer formed by these two materials enables a good match between the hole and electron transport rates, and also provides a high degree of energy level matching between the functional layers. This effectively reduces the device's driving voltage, improves the device's luminous efficiency, and extends the device's lifespan.

[0006]

[0007] In formula (I), Ar1 and Ar2 are independently selected from one of the following structures:

[0008]

[0009] Wherein, each time a1 appears, it is selected from 0, 1, 2, 3 or 4, the same or different; each time b1 appears, it is selected from 0, 1, 2 or 3, the same or different; each time c1 appears, it is selected from 0, 1, 2, 3, 4 or 5, the same or different.

[0010] R1 and R2 are independently selected from hydrogen atoms, deuterium atoms, halogen atoms, cyano groups, and substituted or substituted C1-C12 alkyl groups;

[0011] Each time R3 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring. Two adjacent R3s can be linked to form one of the following: a substituted or unsubstituted C3-C7 aliphatic ring or a substituted or unsubstituted C6-C10 aromatic ring.

[0012] The Ar3 is selected from one of the following: a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aromatic ring fused with a C3-C7 aliphatic ring;

[0013] The L1 to L3 are independently selected from one of the following: a single bond, a substituted or unsubstituted C6 to C30 arylene group, or a divalent group formed by the fusion of a substituted or unsubstituted C6 to C30 aromatic ring and a C3 to C7 aliphatic ring;

[0014] In equation (II), the a 101 Choose from 0, 1, 2, or 3;

[0015] The R mentioned 101 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, substituted or unsubstituted C3-C30 heteroaryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring.

[0016] The Ar 101 ~Ar 106 Independently selected from one of the following structures:

[0017]

[0018] Wherein, the a 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, or 5, either identically or differently; the b mentioned 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either identically or differently; c 102 Each time it appears, it is selected from 0, 1, 2, or 3, either identically or differently; the d mentioned 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different.

[0019] The R mentioned 102 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted phenyl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring.

[0020] The R mentioned 103 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1 to C12 alkyl group;

[0021] The L mentioned 101 ~L 106 Independently selected from a single bond or one of the following structures:

[0022]

[0023] Wherein, the a 103 Each time it appears, it is selected from 0, 1, 2, 3, or 4, either identically or differently; the b mentioned 103 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either identically or differently; c 103 Each time it appears, it is selected from 0, 1, or 2, either identically or differently; the d mentioned 103 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different.

[0024] The R mentioned 104 Each time it appears, it is selected from one of the following, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, or phenyl group substituted or unsubstituted by deuterium atom.

[0025] The R mentioned 105 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1 to C12 alkyl group.

[0026] Beneficial effects:

[0027] The hole transport region of the organic electroluminescent device provided by the present invention includes one or more hole transport layers (one, two, or three layers) and a light-emitting auxiliary layer. The hole transport layer contains the compound shown in formula (I), and the light-emitting auxiliary layer contains the compound shown in formula (II). When there are multiple hole transport layers (two or three layers), the compound of each hole transport layer is different. The hole transport region with the above-mentioned layer structure enables the device to have appropriate hole transport capability and exciton blocking capability, and the organic functional layers can be well matched, so that the driving voltage, luminous efficiency and lifespan are well improved. Detailed Implementation

[0028] The technical solutions of this invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this invention.

[0029] In the compounds of this invention, any atom not specified as a particular isotope is included as any stable isotope of that atom, and comprises atoms at both their natural and non-natural isotopic abundances. Taking hydrogen as an example, each hydrogen atom in all naturally occurring compounds contains about 0.0156 atomic percent deuterium.

[0030] In this invention, the use of "H" and "hydrogen atom" refers to the presence of no more than the natural abundance of deuterium or tritium atoms in the chemical structure, for example, no more than 0.0156 atomic% of deuterium. "D" and "deuterium atom" refer to a deuterium abundance greater than the natural abundance, for example, any value exceeding 0.1 atomic%, 1 atomic%, or 10 atomic%, such as approximately 95 atomic% of deuterium. "T" and "tritium atom" refer to a tritium abundance greater than the natural abundance, for example, any value exceeding 0.1 atomic%, 1 atomic%, or 10 atomic%, such as approximately 95% of tritium. In this invention, the omission of undrawn hydrogen atoms signifies "H" or "hydrogen atom".

[0031] The halogen atoms mentioned in this invention refer to fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0032] In this invention, "silyl group" refers to a -SiH3 group, and "substituted or unsubstituted silyl group" means that one or more H atoms on the silyl group are substituted or unsubstituted. The "substituted or unsubstituted silyl group" can be formed from -Si(R... k )3 indicates that each R k The same or different groups are selected from the following: hydrogen, deuterium, tritium, cyano, halogen, nitro, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C1-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C2-C60 heteroaryl, fused cycloalcoholic group of substituted or unsubstituted C3-C30 alicyclic and C6-C60 aromatic rings, and fused cycloalcoholic group of substituted or unsubstituted C3-C30 alicyclic and C2-C60 heteroaryl rings. Preferably, each R k The same or different groups are selected from the following: hydrogen, deuterium, tritium, cyano, halogen, nitro, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C3-C30 cycloalkyl. The alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15, even more preferably 1 to 10, and most preferably 1 to 8. The cycloalkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15, even more preferably 3 to 10, and most preferably 3 to 7. The aryl group preferably has 6 to 20 carbon atoms, more preferably 6 to 13, even more preferably 6 to 12, and most preferably 6 to 10. Preferably, each R... kThe same or different groups are selected from the following: hydrogen, deuterium, tritium, cyano, halogen, nitro, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted propyl, substituted or unsubstituted butyl, substituted or unsubstituted pentyl, substituted or unsubstituted hexyl, substituted or unsubstituted heptyl, substituted or unsubstituted octyl, substituted or unsubstituted cyclopropyl, substituted or unsubstituted cyclobutyl, substituted or unsubstituted cyclohexyl, substituted or unsubstituted cycloheptyl, substituted or unsubstituted adamantyl, substituted or unsubstituted norbornel, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl. Preferred substituted silyl groups specifically include, but are not limited to, trimethylsilyl, triethylsilyl, triisopropylsilyl, tert-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, phenylsilyl, etc. The aforementioned substituted silyl group is preferably trimethylsilyl, triethylsilyl, triphenylsilyl, diphenylmethylsilyl, phenyldimethylsilyl, diphenylmethylsilyl, or phenyldimethylsilyl.

[0033] The alkyl group described in this invention refers to a hydrocarbon group formed by removing one hydrogen atom from an alkane molecule. It can be a straight-chain alkyl group or a branched-chain alkyl group, preferably having 1 to 15 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 6 carbon atoms. The straight-chain alkyl group includes methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, etc., but is not limited thereto. The branched-chain alkyl group includes isopropyl, isobutyl, sec-butyl, tert-butyl, isomeric groups of n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, etc., but is not limited thereto. The alkyl group is preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, or n-hexyl.

[0034] The cycloalkyl group described in this invention refers to a hydrocarbon group formed by removing one hydrogen atom from a cycloalkane molecule, preferably having 3 to 15 carbon atoms, more preferably 3 to 12 carbon atoms, and particularly preferably 5 to 10 carbon atoms. Examples may include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, adamantane, norbornane, etc., but are not limited thereto. The aforementioned cycloalkyl groups are preferably cyclopentane, cyclohexane, 1-adamantane, 2-adamantane, or norbornane.

[0035] The cycloalkenyl group described in this invention refers to a hydrocarbon group formed by removing one hydrogen atom from a cycloalkene molecule, preferably having 3 to 15 carbon atoms, more preferably 3 to 12 carbon atoms, and particularly preferably 5 to 10 carbon atoms. Examples may include cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, cycloheptenyl, etc., but are not limited thereto. The aforementioned cycloalkyl groups are preferably cyclopentenyl or cyclohexenyl.

[0036] The heterocyclic alkyl group described in this invention refers to a group formed by removing one hydrogen atom from a heterocyclic molecule that contains at least one heteroatom in addition to carbon atoms. Heteroatoms include nitrogen, oxygen, sulfur, silicon, selenium, and phosphorus atoms, preferably nitrogen, oxygen, or sulfur. It is preferable to contain 1 to 3 heteroatoms, more preferably 1 to 2 heteroatoms, and particularly preferably 1 heteroatom. It is preferable to have 3 to 15 ring atoms, more preferably 3 to 12 ring atoms, and particularly preferably 5 to 6 ring atoms. Examples may include ethylene oxide, cyclothioethylene, propylidinyl, tetrahydropyrrolyl, piperidinyl, morpholinyl, thiomorpholinyl, piperazine, etc., but are not limited thereto. The aforementioned heterocyclic groups are preferably tetrahydropyrrolyl, piperidinyl, morpholinyl, thiomorpholinyl, or piperazine.

[0037] The aryl group mentioned in this invention refers to the general term for the monovalent group remaining after removing a hydrogen atom from the aromatic carbon atom of an aromatic compound molecule. It can be a monocyclic aryl, polycyclic aryl, fused-ring aryl, or a fused group of aryl and aliphatic ring. It preferably has 6 to 25 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably 6 to 14 carbon atoms, and most preferably 6 to 12 carbon atoms. The monocyclic aryl group refers to an aryl group with only one aromatic ring in the molecule, such as phenyl, but not limited to this; the polycyclic aryl group refers to an aryl group with two or more independent aromatic rings in the molecule, such as biphenyl, terphenyl, etc., but not limited to this; the fused-ring aryl group refers to an aryl group with two or more aromatic rings in the molecule that are fused together by sharing two adjacent carbon atoms, such as naphthyl, anthracene, phenanthryl, pyrene, peryl, fluorenyl, benzo[a]fluorenyl, triphenylene, fluoranyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirodifluorenyl, spiro-cyclopentyl-fluorenyl, spiro-cyclohexyl-fluorenyl, spiro-adamantyl-fluorenyl, spiro-cyclopentenyl-fluorenyl, spiro-cyclohexenyl-fluorenyl, etc., but not limited to this. The aryl group is preferably phenyl, biphenyl, terphenyl, 1-naphthyl, 2-naphthyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirodifluorenyl, spiro-cyclopentyl-fluorenyl, spiro-cyclohexyl-fluorenyl, spiro-adamantyl-fluorenyl, spiro-cyclopentenyl-fluorenyl, or spiro-cyclohexenyl-fluorenyl.

[0038] The heteroaryl group described in this invention refers to the general term for groups obtained by replacing one or more aromatic carbon atoms in an aryl group with heteroatoms. The heteroatoms include, but are not limited to, oxygen, sulfur, nitrogen, silicon, selenium, or phosphorus atoms, preferably having 1 to 25 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 3 to 15 carbon atoms, and most preferably 3 to 12 carbon atoms. The linking site of the heteroaryl group can be located on a cyclic carbon atom or on a cyclic nitrogen atom. The heteroaryl group can be a monocyclic heteroaryl, a polycyclic heteroaryl, or a fused-ring heteroaryl. The monocyclic heteroaryl groups include, but are not limited to, pyridinyl, pyrimidinyl, triazinyl, furanyl, thiopheneyl, pyrroleyl, imidazolyl, etc.; the polycyclic heteroaryl groups include, but are not limited to, bipyridinyl, bipyrimidinyl, phenylpyridinyl, etc.; the fused-ring heteroaryl groups include, but are not limited to, quinolinyl, isoquinolinyl, indolyl, benzothiopheneyl, benzofuranyl, benzoxazolyl, benzoimidazolyl, benzothiazolyl, dibenzofuranyl, benzodibenzofuranyl, dibenzothiopheneyl, benzodibenzothiapheneyl, carbazolyl, benzocarbazolyl, acridinel, 9,10-dihydroacridinyl, phenoxazinyl, phenthiazinyl, phenoxthiazyl, etc., but are not limited to. The aforementioned heteroaryl groups are preferably pyridyl, pyrimidinyl, thiophene, furanyl, benzothiophene, benzofuranyl, benzooxazolyl, benzoimidazolyl, benzothiazolyl, dibenzofuranyl, dibenzothiophene, benzodibenzothiophene, benzodibenzofuranyl, carbazolyl, acridinel, phenoxazinyl, phenthiazinyl, and phenoxthialyl.

[0039] The term "group formed by the fusion of aromatic and aliphatic rings" as used in this invention refers to the collective term for a monovalent group formed by the fusion of an aromatic ring and an aliphatic ring (cycloalkyl, cycloalkenyl, cycloynyl) and the removal of one hydrogen atom. The aromatic ring preferably has 6 to 25 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably 6 to 14 carbon atoms, and most preferably 6 to 12 carbon atoms. It may include, but is not limited to, benzene, naphthalene, anthracene, phenanthrene, etc. The aliphatic ring preferably has 3 to 9 carbon atoms, more preferably 5 to 7 carbon atoms. It may include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclopropene, cyclobutene, cyclopentene, cycloheptene, cyclopropyne, cyclobutyne, cyclopentyne, cyclohexyne, and cycloheptyne. Preferably, examples of groups formed by the fusion of an aromatic ring and an aliphatic ring may include, but are not limited to, benzocyclopropyl, benzocyclobutyl, benzocyclopentyl, benzocyclohexyl, benzocycloheptyl, benzocyclopentenyl, benzocyclohexenyl, benzocycloheptenyl, naphthocyclopropyl, naphthocyclobutyl, naphthocyclopentyl, naphthocyclohexyl, etc.

[0040] In this invention, the term arylene refers to an aryl group having two bonding sites, i.e., a divalent group. The above description of aryl groups can be applied to it, the difference being that arylene is a divalent group.

[0041] In this invention, the term "hybrid aryl" refers to a heteroaryl group having two bonding sites, i.e., a divalent group. The above description of heteroaryl groups can be applied to it, the difference being that the hybrid aryl group is a divalent group.

[0042] The divalent group formed by the fusion of an aromatic ring and an aliphatic ring as described in this invention refers to a group formed by the fusion of an aromatic ring and an aliphatic ring having two bonding sites, i.e., a divalent group. It can be applied to the above description of groups formed by the fusion of an aromatic ring and an aliphatic ring, the difference being that the divalent group formed by the fusion of an aromatic ring and an aliphatic ring is a divalent group.

[0043] The term "substitution" as used in this invention refers to the replacement of a hydrogen atom in certain functional groups by another atom or functional group (i.e., a substituent), and the position of substitution is not limited, as long as the position is where the hydrogen atom is substituted. Furthermore, when two or more are substituted, the two or more substituents may be the same as or different from each other.

[0044] In this invention, "substituted or unsubstituted" means either unsubstituted or substituted with one or more substituents selected from the group consisting of: deuterium atom, halogen atom, amino, cyano, nitro, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C3-C30 cycloalkenyl, substituted or unsubstituted C3-C30 heterocycloalkyl, substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C6-C60 aryloxy, substituted or unsubstituted C2-C60 heteroaryl, substituted or unsubstituted silyl, preferably deuterium atom, halogen atom, cyano, nitro, C1-C12 alkyl, C3-C12 cycloalkyl, C The 3-C12 cycloalkenyl, C3-C12 heterocycloalkyl, C6-C30 aryl, C3-C30 heteroaryl, substituted or unsubstituted silyl groups, wherein the substituted groups are the same or different from each other when substituted by multiple substituents; preferably, it means unsubstituted or substituted by one or more substituents selected from the group consisting of: deuterium, fluorine, cyano, methyl, trifluoromethyl, deuterated methyl, ethyl, deuterated ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, deuterated tert-butyl, n-pentyl, n-hexyl, cyclopropane, methyl-substituted cyclopropane, ethyl-substituted cyclopropane, deuterated cyclopropane, cyclobutane, methyl-substituted cyclobutane, ethyl-substituted cyclobutane Alkyl, deuterated cyclobutyl, cyclopentyl, methyl-substituted cyclopentyl, ethyl-substituted cyclopentyl, deuterated cyclopentyl, cyclohexyl, methyl-substituted cyclohexyl, ethyl-substituted cyclohexyl, n-propyl-substituted cyclohexyl, n-butyl-substituted cyclohexyl, cyclohexane-substituted cyclohexyl, deuterated cyclohexyl, cycloheptyl, cyclopentenyl, methyl-substituted cyclopentenyl, ethyl-substituted cyclopentenyl, cyclohexenyl, cycloheptenyl, adamantyl, methyl-substituted adamantyl, ethyl-substituted adamantyl, deuterated adamantyl, norbornyl, methyl-substituted norbornyl, ethyl-substituted norbornyl, deuterated norbornyl, tetrahydropyrrolyl, piperidinyl, morpholinyl, thiomorpholinyl, methyl-substituted Piperazinyl, ethyl-substituted piperazinyl, phenyl-substituted piperazinyl, naphthyl-substituted piperazinyl, phenyl, deuterated phenyl, naphthyl, deuterated naphthyl, anthraceneyl, deuterated anthraceneyl, phenanthryl, deuterated phenanthryl, triphenylene, pyrene, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirodifluorenyl, spiro-cyclopentyl-fluorenyl, spiro-cyclohexyl-fluorenyl, spiro-adamantyl-fluorenyl, spiro-cyclopentenyl-fluorenyl, spiro-cyclohexenyl-fluorenyl, pyridyl, pyrimidinyl, triazinyl, quinolinyl, isoquinolinyl, quinazolinyl, quinoxalinyl, N-phenylcarbazoyl, dibenzofuranyl, dibenzothiophenyl, trimethylsilyl, triphenylsilyl, where the multiple substituents are the same or different from each other.

[0045] In this specification, when the position of a substituent or linker site on the ring is not fixed, it means that it can be linked to any of the optional sites on the ring. For example, Can represent Can represent Can represent And so on.

[0046] In this specification, when a substituent or linking site lies within a bond that extends through two or more rings, it indicates that the substituent or linking site can be linked to any one of the two or more rings, specifically to any one of the corresponding optional sites within the rings. For example, Can represent Can represent Can represent And so on.

[0047] The linked ring structure described in this invention (e.g., forming saturated or unsaturated C3-C10 carbon rings, forming substituted or unsubstituted saturated or unsaturated C3-C6 carbon rings) refers to the individual groups being connected to each other by chemical bonds, optionally forming double / triple bonds, and can constitute aromatic groups, as shown in the following examples:

[0048]

[0049] In this invention, the ring formed by the connection can be an aromatic ring system, an aliphatic ring system, or a ring system formed by the fusion of the two. The ring formed by the connection can be a three-membered ring, a four-membered ring, a five-membered ring, a six-membered ring, a spiro ring, or a fused ring, such as benzene, naphthalene, indene, cyclopentene, cyclopentane, cyclopentanophenene, cyclohexene, cyclohexane, cyclohexanophenene, pyridine, quinoline, isoquinoline, benzofuran, benzothiophene, dibenzofuran, dibenzothiophene, phenanthrene, or pyrene, but is not limited thereto.

[0050] In this specification, "at least one" includes one, two, three, four, five, six, seven, eight or more.

[0051] The statement that a certain layer is located "above" another layer or electrode in this invention can be interpreted as being directly above another layer or electrode, or it can be that other layer structures exist in between.

[0052] The term "a certain layer" in this invention, which is "between" two layers, two electrodes, or one layer and an electrode, can be interpreted as the only layer structure between the two, or as having one or more layer structures between them.

[0053] This invention provides an organic electroluminescent device, comprising an anode, a cathode, and an organic layer, wherein the organic layer is located between the anode and the cathode, and the organic layer includes a hole transport region, a light-emitting layer, and an electron transport region. The hole transport region includes a first hole transport layer and a light-emitting auxiliary layer, wherein the first hole transport layer is located between the anode and the light-emitting layer, and the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer. The first hole transport layer contains one of the compounds shown in formula (I), and the light-emitting auxiliary layer contains one of the compounds shown in formula (II).

[0054]

[0055] In formula (I), Ar1 and Ar2 are independently selected from one of the following structures:

[0056]

[0057] Wherein, each time a1 appears, it is selected from 0, 1, 2, 3 or 4, the same or different; each time b1 appears, it is selected from 0, 1, 2 or 3, the same or different; each time c1 appears, it is selected from 0, 1, 2, 3, 4 or 5, the same or different.

[0058] R1 and R2 are independently selected from hydrogen atoms, deuterium atoms, halogen atoms, cyano groups, and substituted or substituted C1-C12 alkyl groups;

[0059] Each time R3 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring. Two adjacent R3s can be linked to form one of the following: a substituted or unsubstituted C3-C7 aliphatic ring or a substituted or unsubstituted C6-C10 aromatic ring.

[0060] The Ar3 is selected from one of the following: a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aromatic ring fused with a C3-C7 aliphatic ring;

[0061] The L1 to L3 are independently selected from one of the following: a single bond, a substituted or unsubstituted C6 to C30 arylene group, or a divalent group formed by the fusion of a substituted or unsubstituted C6 to C30 aromatic ring and a C3 to C7 aliphatic ring;

[0062] In equation (II), the a 101 Choose from 0, 1, 2, or 3;

[0063] The R mentioned 101 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, substituted or unsubstituted C3-C30 heteroaryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring.

[0064] The Ar 101 ~Ar 106 Independently selected from one of the following structures:

[0065]

[0066] Wherein, the a 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, or 5, either identically or differently; the b mentioned 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either identically or differently; c 102 Each time it appears, it is selected from 0, 1, 2, or 3, either identically or differently; the d mentioned 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different.

[0067] The R mentioned 102 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted phenyl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring.

[0068] The R mentioned 103 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1 to C12 alkyl group;

[0069] The L mentioned 101 ~L 106 Independently selected from a single bond or one of the following structures:

[0070]

[0071] Wherein, the a 103 Each time it appears, it is selected from 0, 1, 2, 3, or 4, either identically or differently; the b mentioned 103 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either identically or differently; c103 Each time it appears, it is selected from 0, 1, or 2, either identically or differently; the d mentioned 103 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different.

[0072] The R mentioned 104 Each time it appears, it is selected from one of the following, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, or phenyl group substituted or unsubstituted by deuterium atom.

[0073] The R mentioned 105 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1 to C12 alkyl group.

[0074] Preferably, R1 and R2 are both selected from one of methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, deuterated tert-butyl, n-pentyl, and n-hexyl.

[0075] Preferably, each time R3 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, fluorine atom, cyano, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, deuterated tert-butyl, n-pentyl, n-hexyl, adamantyl, norbornel, trimethylsilyl, triphenylsilyl, phenyl, and deuterated phenyl.

[0076] Preferably, Ar1 and Ar2 are independently selected from one of the following structures:

[0077]

[0078] Wherein, the a 31 Each time it appears, it is selected from 0, 1, 2, 3, or 4, either identically or differently; the b mentioned 31 Each time it appears, it is selected from 0, 1, 2, or 3, either identically or differently; the c mentioned 31 Each time it appears, it is selected from 0, 1, 2, 3, 4, or 5, either identically or differently; the d mentioned 31 Each time it appears, it is selected from 0, 1, or 2, either the same or different.

[0079] The R mentioned 31 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, fluorine atom, cyano, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, deuterated tert-butyl, n-pentyl, n-hexyl, adamantyl, norbornel, trimethylsilyl, triphenylsilyl, phenyl, and deuterated phenyl.

[0080] Preferably, Ar1 and Ar2 are independently selected from one of the following structures:

[0081]

[0082]

[0083] Preferably, the Ar3 is selected from one of the following structures:

[0084]

[0085] Wherein, each occurrence of a3 is selected from 0, 1, 2, 3, 4, or 5, either the same or different; each occurrence of b3 is selected from 0, 1, 2, 3, or 4, either the same or different; each occurrence of c3 is selected from 0, 1, 2, or 3, either the same or different; each occurrence of d3 is selected from 0, 1, or 2, either the same or different; each occurrence of e3 is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different; and each occurrence of f3 is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either the same or different.

[0086] Each time R6 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring.

[0087] Each time R7 appears, it is selected from one of hydrogen atoms, deuterium atoms, halogen atoms, cyano groups, substituted or unsubstituted C1 to C12 alkyl groups, either the same or different.

[0088] Preferably, each time R6 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, fluorine atom, cyano, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, deuterated tert-butyl, n-pentyl, n-hexyl, adamantyl, norbornel, trimethylsilyl, triphenylsilyl, phenyl, and deuterated phenyl.

[0089] Preferably, each time R7 appears, it is selected from one of hydrogen atom, deuterium atom, fluorine atom, cyano, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, and deuterated tert-butyl, either the same or different.

[0090] Preferably, the Ar3 is selected from one of the following structures:

[0091]

[0092]

[0093] Preferably, L1 to L3 are independently selected from a single bond or one of the following structures:

[0094]

[0095] Wherein, each occurrence of a2 is selected from 0, 1, 2, 3, or 4, either the same or different; each occurrence of b2 is selected from 0, 1, 2, or 3, either the same or different; each occurrence of c2 is selected from 0, 1, or 2, either the same or different; each occurrence of d2 is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different; and each occurrence of e2 is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either the same or different.

[0096] Each time R4 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring.

[0097] Each time R5 appears, it is selected from one of hydrogen atoms, deuterium atoms, halogen atoms, cyano groups, substituted or unsubstituted C1 to C12 alkyl groups, either the same or different.

[0098] Preferably, each time R4 appears, it is selected from one of the following groups: hydrogen atom, deuterium atom, fluorine atom, cyano, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, deuterated tert-butyl, trimethylsilyl, phenyl, and deuterated phenyl.

[0099] Preferably, each time R5 appears, it is selected from one of hydrogen atom, deuterium atom, fluorine atom, cyano, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, and deuterated tert-butyl, either the same or different.

[0100] Preferably, L1 to L3 are independently selected from a single bond or one of the following structures:

[0101]

[0102]

[0103] Preferably, the R 102Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, fluorine atom, cyano, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, deuterated tert-butyl, n-pentyl, n-hexyl, adamantyl, norbornel, trimethylsilyl, triphenylsilyl, phenyl, and deuterated phenyl.

[0104] Preferably, the R 103 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, fluorine atom, cyano group, methyl group, deuterated methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, isobutyl group, tert-butyl group, and deuterated tert-butyl group.

[0105] Preferably, the Ar 101 ~Ar 106 Independently selected from one of the following structures:

[0106]

[0107] Preferably, the R 104 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, fluorine atom, cyano, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, deuterated tert-butyl, trimethylsilyl, phenyl, and deuterated phenyl.

[0108] Preferably, the R 105 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, fluorine atom, cyano group, methyl group, deuterated methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, isobutyl group, tert-butyl group, and deuterated tert-butyl group.

[0109] Preferably, the L 101 ~L 106 Independently selected from a single bond or one of the following structures:

[0110]

[0111] Preferably, the compound represented by formula (I) is selected from one of the compounds represented by formulas (IA) to (IF):

[0112]

[0113] Wherein, Ar3, L1~L3, a1, b1, c1, R1, R2, and R3 are as described in this invention.

[0114] Preferably, the compound represented by formula (I) is selected from one of the following compounds:

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122] .

[0123] Preferably, the compound represented by formula (II) is selected from one of the compounds represented by formulas (II-A) to (II-D) as follows:

[0124]

[0125] Among them, the Ar 101 ~Ar 106 L 101 ~L 106 All as described in this invention;

[0126] The R mentioned 201 Each time it appears, it is always selected from one of the following: deuterium atom, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, and deuterated tert-butyl.

[0127] Preferably, the compound represented by formula (II) is selected from one of the following compounds:

[0128]

[0129]

[0130]

[0131]

[0132]

[0133]

[0134] The organic electroluminescent device of the present invention includes an anode, a hole transport region above the anode, a light-emitting layer above the hole transport region, an electron transport region above the light-emitting layer, and a cathode above the electron transport region.

[0135] The organic electroluminescent device of the present invention may further include a capping layer on top of the cathode.

[0136] The anode described in this invention can be a reflective anode, such as a reflective film formed of silver (Ag), magnesium (Mg), aluminum (Al), gold (Au), nickel (Ni), chromium (Cr), ytterbium (Yb), or their alloys. It can also be a layered structure with a high work function that is transparent or semi-transparent, such as a layered structure formed of indium tin oxide (ITO), indium zinc oxide (ZnO), zinc oxide (ZnO), aluminum zinc oxide (AZO), indium gallium oxide (IGO), indium oxide (In2O3), or tin oxide (SnO2). The specific anode depends on the type of device to be fabricated. For example, if the device to be fabricated is a bottom-emitting device (emitting light from the anode side), a transparent or semi-transparent anode needs to be fabricated. If the device to be fabricated is a top-emitting device (emitting light from the cathode side), a reflective anode needs to be fabricated.

[0137] The hole transport region described in this invention includes one or more organic functional layers selected from the hole injection layer, hole transport layer, and light emission auxiliary layer.

[0138] The hole injection layer described in this invention can be a monolayer structure composed of a single substance, or a monolayer or multilayer structure composed of different substances. Triarylamine compounds, porphyrin compounds, styrene compounds, polythiophene and its derivatives, phthalocyanine derivatives, axialene compounds, and other substances with high hole injection properties can be used, such as 4,4',4”-tris[2-naphthylphenylamino]triphenylamine (2-TNATA), 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazabenzenephenanthrene (HATCN), copper phthalocyanine (CuPC), 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone (F4-TCNQ), poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) (PEDOT / PSS), compounds HT-1 to HT-11, compounds p-1 to p-3, and compounds shown in formula (I) of this invention, but not limited thereto.

[0139]

[0140] Preferably, the hole injection layer is a single-layer structure composed of a single material, such as 2-TNATA, HATCN, CuPC, etc.

[0141] Preferably, the hole injection layer is a monolayer structure composed of different substances. More preferably, the hole injection layer is a monolayer structure composed of two substances: one substance is a triarylamine compound, such as compounds HT-1 to HT-11, or the compound shown in formula (I) of this invention; the other substance is an axylene compound or other substances with high hole injection properties, such as HATCN, F4-TCNQ, or compounds p-1 to p-3.

[0142] The hole transport layer described in this invention can be a monolayer structure composed of a single material, or a monolayer or multilayer structure composed of different materials. Triarylamine compounds can be used, or other compounds with a hole mobility of 10... -6 cm 2 Substances with a concentration of / Vs or higher, such as N,N'-diphenyl-N,N'-di(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD), N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPB), 4,4'4"-tris(N,N-diphenylamino)triphenylamine (TDATA), compounds HT-1 to HT-11 as shown above, and compounds of formula (I) of this invention, but not limited thereto.

[0143] Preferably, the hole transport layer is a single-layer structure composed of a single substance, which is the compound shown in formula (I).

[0144] Preferably, the hole transport layer is a single-layer structure composed of different substances, all of which are selected from the compounds shown in Formula (I), and each substance is a different compound. More preferably, the hole transport layer is a single-layer structure composed of two substances, both of which are selected from the compounds shown in Formula (I), and the two substances are different compounds.

[0145] Preferably, the hole transport layer is a multilayer structure composed of different substances, all of which are selected from the compounds shown in Formula (I), and each substance is a different compound. More preferably, the hole transport layer is a bilayer structure composed of two substances, both of which are selected from the compounds shown in Formula (I), and the two substances are different compounds. Even more preferably, the hole transport layer is a bilayer structure composed of two substances, both of which are selected from the compounds shown in Formula (I), and the two substances are different compounds, with each layer containing only one substance.

[0146] The luminescent auxiliary layer described in this invention can be a single-layer structure composed of a single substance, or a single-layer or multi-layer structure composed of different substances. Triarylamine compounds, spirofluorene derivatives, dibenzofuran derivatives, or other substances with suitable HOMO and T1 energy levels can be used. Examples include TPD, NPB, N4,N4-bis([1,1'-biphenyl]-4-yl)-N4'-phenylN4'-[1,1':4',1”-terphenyl]-4-yl-[1,1'-biphenyl]-4,4'-diamine, N-([1, 1'-diphenyl]-4-yl)-N-(9,9-dimethyl-9H-furan-2-yl)-9,9'-spirodifluorene-2-amine, N,N-di([1,1'-biphenyl]-4-yl)-3'-(dibenzo[b,d]furan-4-yl)-[1,1'-biphenyl]-4-amine, compounds HT-1 to HT-11 as shown above, and compounds shown in formula (II) of this invention, but not limited thereto.

[0147] Preferably, the light-emitting auxiliary layer is a single-layer structure composed of a single substance, which is the compound shown in formula (II).

[0148] Preferably, the light-emitting auxiliary layer is a single-layer structure composed of different substances, all of which are selected from compounds shown in Formula (II), and each substance is a different compound. More preferably, the light-emitting auxiliary layer is a single-layer structure composed of two substances, both of which are selected from compounds shown in Formula (II), and the two substances are different compounds.

[0149] Preferably, the light-emitting auxiliary layer is a multilayer structure composed of different substances, all of which are selected from compounds shown in Formula (II), and each substance is a different compound. More preferably, the light-emitting auxiliary layer is a bilayer structure composed of two substances, both of which are selected from compounds shown in Formula (II), and the two substances are different compounds. Even more preferably, the light-emitting auxiliary layer is a bilayer structure composed of two substances, both of which are selected from compounds shown in Formula (II), and the two substances are different compounds, with each layer containing only one substance.

[0150] Preferably, the hole transport region includes a hole transport layer (first hole transport layer) and a light-emitting auxiliary layer: the first hole transport layer is located between the anode and the light-emitting layer, the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer, the first hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I), and the light-emitting auxiliary layer is a monolayer structure composed of a single substance, which is the compound shown in formula (II).

[0151] Preferably, the hole transport region includes a hole transport layer (first hole transport layer) and a light-emitting auxiliary layer: the first hole transport layer is located between the anode and the light-emitting layer, and the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer. The first hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I); the light-emitting auxiliary layer is a bilayer structure composed of two substances, both of which are selected from the compound shown in formula (II), and the two substances are different compounds.

[0152] Preferably, the hole transport region comprises two hole transport layers (a first hole transport layer and a second hole transport layer) and a light-emitting auxiliary layer: the first hole transport layer is located between the anode and the light-emitting layer; the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer; and the second hole transport layer is located between the first hole transport layer and the light-emitting auxiliary layer. The first hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I); the second hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I), and is different from the compound in the first hole transport layer; the light-emitting auxiliary layer is a monolayer structure composed of a single substance, which is the compound shown in formula (II).

[0153] Preferably, the hole transport region comprises two hole transport layers (a first hole transport layer and a second hole transport layer) and a light-emitting auxiliary layer: the first hole transport layer is located between the anode and the light-emitting layer, the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer, and the second hole transport layer is located between the first hole transport layer and the light-emitting auxiliary layer. The first hole transport layer is a monolayer structure composed of a single substance selected from the compounds shown in formula (I); the second hole transport layer is a monolayer structure composed of a single substance selected from the compounds shown in formula (I), and is different from the compounds in the first hole transport layer; the light-emitting auxiliary layer is a bilayer structure composed of two substances, both of which are selected from the compounds shown in formula (II), and are different compounds.

[0154] Preferably, the hole transport region comprises two hole transport layers (a first hole transport layer and a second hole transport layer) and a light-emitting auxiliary layer: the first hole transport layer is located between the anode and the light-emitting layer, the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer, and the second hole transport layer is located between the light-emitting auxiliary layer and the light-emitting layer. The first hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I); the second hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I), and is different from the compound in the first hole transport layer; the light-emitting auxiliary layer is a monolayer structure composed of a single substance, which is the compound shown in formula (II).

[0155] Preferably, the hole transport region comprises two hole transport layers (a first hole transport layer and a second hole transport layer) and a light-emitting auxiliary layer: the first hole transport layer is located between the anode and the light-emitting layer, the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer, and the second hole transport layer is located between the light-emitting auxiliary layer and the light-emitting layer. The first hole transport layer is a monolayer structure composed of a single substance selected from the compounds shown in formula (I); the second hole transport layer is a monolayer structure composed of a single substance selected from the compounds shown in formula (I), and is different from the compounds in the first hole transport layer; the light-emitting auxiliary layer is a bilayer structure composed of two substances, both of which are selected from the compounds shown in formula (II), and are different compounds.

[0156] Preferably, the hole transport region comprises three hole transport layers (a first hole transport layer, a second hole transport layer, and a third hole transport layer) and a light-emitting auxiliary layer: the first hole transport layer is located between the anode and the light-emitting layer; the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer; the second hole transport layer is located between the first hole transport layer and the light-emitting auxiliary layer; and the third hole transport layer is located between the light-emitting auxiliary layer and the light-emitting layer. The first hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I); the second hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I), and is different from the compound in the first hole transport layer; the third hole transport layer is a monolayer structure composed of a single substance selected from the compound shown in formula (I), and is different from both the compounds in the first and second hole transport layers; the light-emitting auxiliary layer is a monolayer structure composed of a single substance, which is the compound shown in formula (II).

[0157] Preferably, the hole transport region comprises three hole transport layers (a first hole transport layer, a second hole transport layer, and a third hole transport layer) and a light-emitting auxiliary layer: the first hole transport layer is located between the anode and the light-emitting layer; the light-emitting auxiliary layer is located between the first hole transport layer and the light-emitting layer; the second hole transport layer is located between the first hole transport layer and the light-emitting auxiliary layer; and the third hole transport layer is located between the light-emitting auxiliary layer and the light-emitting layer. The first hole transport layer is a monolayer structure composed of a single substance selected from the compounds shown in formula (I); the second hole transport layer is a monolayer structure composed of a single substance selected from the compounds shown in formula (I), and is different from the compounds in the first hole transport layer; the third hole transport layer is a monolayer structure composed of a single substance selected from the compounds shown in formula (I), and is different from both the compounds in the first and second hole transport layers; the light-emitting auxiliary layer is a bilayer structure composed of two substances, both of which are selected from the compounds shown in formula (II), and are different compounds.

[0158] The luminescent layer of the present invention comprises a guest material and a host material, and a dual host material formed by two host materials can be used. The guest material can be a fluorescent compound, such as pyrene derivatives, fluoranthene derivatives, aromatic amine derivatives, etc. Examples include 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyran[6,7,8-ij]quinolinazine-11-one (C545T), 4,4'-bis(9-ethyl-3-carbazolevinyl)-1,1'-biphenyl (BCzVBi), 4, 4'-Bis[4-(di-p-tolylamino)styryl]biphenyl (DPAVBi) and other materials can also be used, such as phosphorescent materials, metal complexes such as iridium complexes, osmium complexes, and platinum complexes. Examples include bis(4,6-difluorophenylpyridine-N,C2)pyridineformyliridium (FIrpic), tris(2-phenylpyridine)iridium (Ir(ppy)3), and bis(2-phenylpyridine)iridium acetylacetonate (Ir(ppy)2(acac)). The host material is preferably a substance with a higher LUMO than the guest material and a lower HOMO than the guest material. Examples include metal complexes such as aluminum complexes or zinc complexes, heterocyclic compounds such as oxadiazole derivatives, benzoxazole derivatives, benzothiazole derivatives or benzimidazole derivatives, fused aromatic compounds such as carbazole derivatives or anthracene derivatives, and aromatic amine compounds such as triaromatic amine derivatives or fused polycyclic aromatic amine derivatives. Examples include Alq3, BAlq, TPBI, TPD, 4,4'-bis(9-carbazole)biphenyl (CBP), 4,4',4”-tris(carbazole-9-yl)triphenylamine (TCTA), and 9,10-bis(2-naphthyl)anthracene (ADN), but are not limited to these.

[0159] The electron transport region of the present invention includes at least one of an electron injection layer, an electron transport layer, and a hole blocking layer.

[0160] The electron injection layer described in this invention can be a monolayer structure composed of a single substance, or a monolayer or multilayer structure composed of different substances. It can be one or more of the following substances: alkali metals, alkaline earth metals, alkali metal halides, alkaline earth metal halides, alkali metal oxides, alkaline earth metal oxides, alkali metal salts, alkaline earth metal salts, and other substances with high electron injection properties. Examples include Li, Ca, Sr, LiF, CsF, CaF2, BaO, Li2CO3, CaCO3, Li2C2O4, Cs2C2O4, CsAlF4, LiOx, Yb, Tb, etc., but are not limited to these.

[0161] The electron transport layer described in this invention can be a single-layer structure composed of a single substance, or a single-layer or multi-layer structure composed of different substances. It can use aluminum complexes, lithium complexes, beryllium complexes, zinc complexes, oxazole derivatives, benzoxazole derivatives, thiazole derivatives, benzothiazole derivatives, imidazole derivatives, benzimidazole derivatives, carbazole derivatives, phenanthroline derivatives, polymers, etc. Examples include 8-hydroxyquinoline aluminum (Alq3), bis(10-hydroxybenzo[h]quinoline) beryllium (BeBq2), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-hydroxy)aluminum (BAlq), 2-(4-biphenyl)-5-phenyloxadiazole (PBD), but is not limited to these.

[0162] The hole-blocking layer described in this invention can be a single-layer structure composed of a single material, or a single-layer or multi-layer structure composed of different materials. The selected material must have a T1 energy level higher than that of the emissive layer to prevent energy loss from the emissive layer. Furthermore, the HOMO energy level of the selected material must be lower than that of the main material of the emissive layer to effectively block holes. Further, the electron mobility of the hole-blocking layer material used is 10. -6 cm 2 A value of / Vs or higher facilitates electron transport. One or more of the following substances can be selected: aluminum complexes, lithium complexes, beryllium complexes, oxazole derivatives, benzoxazole derivatives, thiazole derivatives, benzothiazole derivatives, imidazole derivatives, benzimidazole derivatives, phenanthroline derivatives, and polymers. Examples include 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBI) and BAlq, but these are not limited to these.

[0163] The cathode described in this invention can be a thin film with a low work function made of lithium, calcium, lithium fluoride / calcium, lithium fluoride / aluminum, aluminum, silver, magnesium, magnesium-silver alloy, etc. The thickness of the film can be adjusted to make a reflective electrode, a transparent electrode, or a semi-transparent electrode. If a bottom-emitting device is to be made, a reflective cathode needs to be made. If a top-emitting device is to be made, a transparent or semi-transparent cathode needs to be made.

[0164] The capping layer described in this invention can be a single-layer structure composed of a single material, or a single-layer or multi-layer structure composed of different materials. The capping layer material can be an organic or inorganic substance with an appropriate refractive index, such as metal halides, oxides, nitrides, nitrogen oxides, sulfides, selenides, aromatic compounds, heteroaromatic compounds, aromatic amine compounds, etc. Examples include LiF, CsF, MgF2, CaF2, CsCl, CuI, V2O5, WO3, MoO3, TiO2, ZrO, ZnO, SiO2, SiN, ZnS, Alq3, compound CP-1, compound CP-2, compound CP-3, and compound CP-4, but are not limited thereto.

[0165]

[0166] Preferably, the structure of the organic electroluminescent device is one of the following device structures:

[0167] 1) Anode / Hole Injection Layer / First Hole Transport Layer / Light Emitting Assist Layer / Light Emitting Layer / Electron Transport Layer / Electron Injection Layer / Cathode;

[0168] 2) Anode / Hole Injection Layer / First Hole Transport Layer / Light Emitting Assist Layer / Light Emitting Layer / Hole Blocking Layer / Electron Transport Layer / Electron Injection Layer / Cathode;

[0169] 3) Anode / Hole injection layer / First hole transport layer / Second hole transport layer / Light emission auxiliary layer / Light emission layer / Electron transport layer / Electron injection layer / Cathode;

[0170] 4) Anode / Hole injection layer / First hole transport layer / Second hole transport layer / Light emission auxiliary layer / Light emission layer / Hole blocking layer / Electron transport layer / Electron injection layer / Cathode;

[0171] 5) Anode / Hole Injection Layer / First Hole Transport Layer / Light Emitting Assist Layer / Second Hole Transport Layer / Light Emitting Layer / Electron Transport Layer / Electron Injection Layer / Cathode;

[0172] 6) Anode / Hole injection layer / First hole transport layer / Light emission auxiliary layer / Second hole transport layer / Light emission layer / Hole blocking layer / Electron transport layer / Electron injection layer / Cathode;

[0173] 7) Anode / Hole Injection Layer / First Hole Transport Layer / Second Hole Transport Layer / Light Emitting Assist Layer / Third Hole Transport Layer / Light Emitting Layer / Electron Transport Layer / Electron Injection Layer / Cathode;

[0174] 8) Anode / Hole injection layer / First hole transport layer / Second hole transport layer / Light emission auxiliary layer / Third hole transport layer / Light emission layer / Hole blocking layer / Electron transport layer / Electron injection layer / Cathode;

[0175] 9) Anode / Hole Injection Layer / First Hole Transport Layer / Light Emitting Assist Layer / Light Emitting Layer / Electron Transport Layer / Electron Injection Layer / Cathode / Capping Layer;

[0176] 10) Anode / Hole Injection Layer / First Hole Transport Layer / Light Emitting Assist Layer / Light Emitting Layer / Hole Blocking Layer / Electron Transport Layer / Electron Injection Layer / Cathode / Capping Layer;

[0177] 11) Anode / Hole Injection Layer / First Hole Transport Layer / Second Hole Transport Layer / Light Emitting Assist Layer / Light Emitting Layer / Electron Transport Layer / Electron Injection Layer / Cathode / Capping Layer;

[0178] 12) Anode / Hole injection layer / First hole transport layer / Second hole transport layer / Light emission auxiliary layer / Light emission layer / Hole blocking layer / Electron transport layer / Electron injection layer / Cathode / Capping layer;

[0179] 13) Anode / Hole Injection Layer / First Hole Transport Layer / Light Emitting Assist Layer / Second Hole Transport Layer / Light Emitting Layer / Electron Transport Layer / Electron Injection Layer / Cathode / Capping Layer;

[0180] 14) Anode / Hole injection layer / First hole transport layer / Light emission auxiliary layer / Second hole transport layer / Light emission layer / Hole blocking layer / Electron transport layer / Electron injection layer / Cathode / Capping layer;

[0181] 15) Anode / Hole Injection Layer / First Hole Transport Layer / Second Hole Transport Layer / Light Emitting Assist Layer / Third Hole Transport Layer / Light Emitting Layer / Electron Transport Layer / Electron Injection Layer / Cathode / Capping Layer;

[0182] 16) Anode / Hole Injection Layer / First Hole Transport Layer / Second Hole Transport Layer / Light Emitting Assist Layer / Third Hole Transport Layer / Light Emitting Layer / Hole Blocking Layer / Electron Transport Layer / Electron Injection Layer / Cathode / Covering Layer.

[0183] The aforementioned organic layers, cathode, and anode can be prepared using any of the following methods: vacuum evaporation, inkjet printing, sputtering, plasma deposition, ion plating, spin coating, dip coating, or screen printing. There are no special limitations on the thickness of each layer, as long as good device performance is achieved. The aforementioned organic layers are preferably prepared using vacuum evaporation, inkjet printing, or spin coating. When using vacuum evaporation, if one of the aforementioned organic layers is a single-layer structure containing multiple substances, a co-evaporation method can be adopted, where multiple substances are simultaneously deposited in a certain mass ratio and at a certain evaporation rate ratio to form an organic layer.

[0184] The thickness of each of the aforementioned organic layers is typically between 5 nm and 100 μm, preferably between 10 nm and 200 nm. The thickness of the anode and cathode is adjusted according to the required transparency.

[0185] The organic electroluminescent device provided by this invention can be applied to lighting and display fields, specifically including smartphone displays, tablet displays, smart wearable device displays, large-size displays such as televisions, VR, and car taillights.

[0186] The technical solutions and effects of the present invention will be further described below with reference to embodiments and comparative examples.

[0187] The mass spectrometry of the compounds in this invention was performed using a G2-Si quadrupole tandem time-of-flight high-resolution mass spectrometer from Waters Instruments, UK, with chloroform as the solvent.

[0188] Elemental analysis was performed using a Vario EL cube organic elemental analyzer from Elementar GmbH, Germany, with sample masses ranging from 5 to 10 mg.

[0189] Synthesis Example 1: Synthesis of Compound HT1-3

[0190]

[0191] Under nitrogen protection, AA-3 (4.66 g, 50 mmol), BB-3 (19.87 g, 50 mmol), sodium tert-butoxide (9.61 g, 100 mmol), and toluene (250 ml) were added to a reaction flask and stirred. Pd(OAc)2 (0.11 g, 0.5 mmol) and a 0.5 M P(t-Bu)3 toluene solution (2 ml) were added to the reaction system. The system was heated to reflux and refluxed for 6 h. After the reaction was complete, the mixture was cooled to room temperature, washed with distilled water, and extracted with dichloromethane. The organic layer was dried over anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. The residue was recrystallized from toluene / methanol (6:1 v / v) to give compound CC-3 (16.79 g, 82% yield). Mass spectrometry m / z: 409.1849 (theoretical value: 409.1830).

[0192] Under nitrogen protection, CC-3 (12.29 g, 30 mmol), DD-3 (11.92 g, 30 mmol), sodium tert-butoxide (5.77 g, 60 mmol), and toluene (150 mL) were added to a reaction flask. While stirring, Pd2(dba)3 (0.32 g, 0.36 mmol) and a 0.5 M P(t-Bu)3 toluene solution (1.5 mL) were added, and the mixture was heated to reflux for 7 h. After the reaction was complete, the mixture was cooled to room temperature, washed with distilled water, and extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. The residue was recrystallized from toluene / methanol (9:1 v / v) to give compound HT1-3 (17.42 g, 80% yield). HPLC analysis showed a solid purity ≥ 99.98%. Mass spectrometry m / z: 725.3066 (theoretical value: 725.3083). Theoretical element content (%) C 56 H 39 N: C, 92.66; H, 5.42; N, 1.93. Measured element content (%): C, 92.68; H, 5.45; N, 1.90.

[0193] Synthesis Example 2: Synthesis of Compound HT1-30

[0194]

[0195] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-30, BB-30, and DD-30, respectively, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-30 (18.68 g, 78% yield). HPLC analysis confirmed a solid purity ≥ 99.95%. Mass spectrometry m / z: 797.3459 (theoretical value: 797.3478). Theoretical elemental content (%) C 59 H 47NSi: C, 88.79; H, 5.94; N, 1.76. Measured elemental content (%): C, 88.80; H, 5.97; N, 1.73.

[0196] Synthesis Example 3: Synthesis of Compound HT1-55

[0197]

[0198] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-50, DD-30, and DD-30, respectively, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-55 (18.05 g, 75% yield). HPLC analysis confirmed a solid purity ≥ 99.99%. Mass spectrometry m / z: 801.3375 (theoretical value: 801.3396). Theoretical elemental content (%) C 62 H 43 N: C, 92.85; H, 5.40; N, 1.75. Measured element content (%): C, 92.84; H, 5.42; N, 1.74.

[0199] Synthesis Example 4: Synthesis of Compound HT1-60

[0200]

[0201] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-55, BB-60, and DD-60, respectively, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-60 (17.56 g, 73% yield). HPLC analysis confirmed a solid purity ≥ 99.95%. Mass spectrometry m / z: 802.0345 (theoretical value: 802.0330). Theoretical elemental content (%) C 62 H 43 N: C, 92.85; H, 5.40; N, 1.75. Measured element content (%): C, 92.86; H, 5.44; N, 1.72.

[0202] Synthesis Example 5: Synthesis of Compound HT1-66

[0203]

[0204] By successively replacing AA-3, BB-3, and DD-3 with equimolar amounts of AA-66, DD-30, and BB-60, and following the same steps as in Synthesis Example 1, compound HT1-66 (17.99 g, yield 74%) was obtained. HPLC analysis showed a solid purity ≥ 99.95%. Mass spectrometry m / z: 810.3979 (theoretical value: 810.3960). Theoretical elemental content (%) C 62 H34 D9N: C, 91.81; H, 6.46; N, 1.73. Measured elemental content (%): C, 91.83; H, 6.42; N, 1.75.

[0205] Synthesis Example 6: Synthesis of Compound HT1-82

[0206]

[0207] Replacing DD-30 with an equimolar amount of DD-82, and following the same steps as in Synthesis Example 3, yielded compound HT1-82 (17.68 g, 71% yield). HPLC analysis showed a solid purity ≥ 99.96%. Mass spectrometry m / z: 829.3721 (theoretical value: 829.3709). Theoretical elemental content (%) C 64 H 47 N: C, 92.61; H, 5.71; N, 1.69. Measured elemental content (%): C, 92.66; H, 5.68; N, 1.68.

[0208] Synthesis Example 7: Synthesis of Compound HT1-94

[0209]

[0210] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-94, DD-30, and BB-60, respectively, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-94 (16.48 g, 69% yield). HPLC analysis confirmed a solid purity ≥ 99.92%. Mass spectrometry m / z: 795.3878 (theoretical value: 795.3865). Theoretical elemental content (%) C 61 H 49 N: C, 92.04; H, 6.20; N, 1.76. Measured elemental content (%): C, 92.06; H, 6.25; N, 1.72.

[0211] Synthesis Example 8: Synthesis of Compound HT1-124

[0212]

[0213] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-124, DD-30, and DD-124, respectively, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-124 (17.75 g, yield 67%). HPLC analysis confirmed a solid purity ≥ 99.96%. Mass spectrometry m / z: 882.4039 (theoretical value: 882.4022). Theoretical elemental content (%) C 68 H 42D5N: C, 92.48; H, 5.93; N, 1.59. Measured elemental content (%): C, 92.47; H, 5.96; N, 1.58.

[0214] Synthesis Example 9: Synthesis of Compound HT1-142

[0215]

[0216] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-142, BB-142, and DD-30, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-142 (16.74 g, 76% yield). HPLC analysis confirmed a solid purity ≥ 99.93%. Mass spectrometry m / z: 733.3720 (theoretical value: 733.3709). Theoretical elemental content (%) C 56 H 47 N: C, 91.64; H, 6.45; N, 1.91. Measured element content (%): C, 91.60; H, 6.44; N, 1.96.

[0217] Synthesis Example 10: Synthesis of Compound HT1-162

[0218]

[0219] By replacing BB-3 and DD-3 with equimolar amounts of BB-162 and DD-162, respectively, and following the same steps as in Synthesis Example 1, compound HT1-162 (15.61 g, yield 77%) was obtained. HPLC analysis showed a solid purity ≥ 99.94%. Mass spectrometry m / z: 675.2912 (theoretical value: 675.2926). Theoretical elemental content (%) C 52 H 37 N: C, 92.41; H, 5.52; N, 2.07. Measured elemental content (%): C, 92.46; H, 5.49; N, 2.06.

[0220] Synthesis Example 11: Synthesis of Compound HT1-202

[0221]

[0222] By successively replacing AA-3, BB-3, and DD-3 with equimolar amounts of AA-55, BB-202, and DD-202, and following the same steps as in Synthesis Example 1, compound HT1-202 (16.26 g, yield 74%) was obtained. HPLC analysis showed a solid purity ≥ 99.95%. Mass spectrometry m / z: 751.3229 (theoretical value: 751.3239). Theoretical elemental content (%) C 58 H41 N: C, 92.64; H, 5.50; N, 1.86. Measured elemental content (%): C, 92.66; H, 5.51; N, 1.85.

[0223] Synthesis Example 12: Synthesis of Compound HT1-207

[0224]

[0225] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-55, BB-162, and DD-202, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-207 (16.02 g, 79% yield). HPLC analysis confirmed a solid purity ≥ 99.97%. Mass spectrometry m / z: 675.2935 (theoretical value: 675.2926). Theoretical elemental content (%) C 52 H 37 N: C, 92.41; H, 5.52; N, 2.07. Measured elemental content (%): C, 92.40; H, 5.57; N, 2.05.

[0226] Synthesis Example 13: Synthesis of Compound HT1-217

[0227]

[0228] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-55, BB-217, and DD-217, respectively, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-217 (15.21 g, 75% yield). HPLC analysis confirmed a solid purity ≥ 99.93%. Mass spectrometry m / z: 675.2908 (theoretical value: 675.2926). Theoretical elemental content (%) C 52 H 37 N: C, 92.41; H, 5.52; N, 2.07. Measured elemental content (%): C, 92.39; H, 5.54; N, 2.08.

[0229] Synthesis Example 14: Synthesis of Compound HT1-241

[0230]

[0231] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-55, BB-241, and DD-241, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-241 (17.38 g, 71% yield). HPLC analysis confirmed a solid purity ≥ 99.91%. Mass spectrometry m / z: 815.4499 (theoretical value: 815.4491). Theoretical elemental content (%) C 62 H 57 N: C, 91.24; H, 7.04; N, 1.72. Measured element content (%): C, 91.29; H, 7.00; N, 1.71.

[0232] Synthesis Example 15: Synthesis of Compound HT1-259

[0233]

[0234] By successively replacing AA-3, BB-3, and DD-3 with equimolar amounts of AA-259, BB-259, and DD-259, and following the same steps as in Synthesis Example 1, compound HT1-259 (15.84 g, yield 67%) was obtained. HPLC analysis showed a solid purity ≥ 99.95%. Mass spectrometry m / z: 787.4196 (theoretical value: 787.4178). Theoretical elemental content (%) C 60 H 53 N: C, 91.44; H, 6.78; N, 1.78. Measured element content (%): C, 91.40; H, 6.80; N, 1.79.

[0235] Synthesis Example 16: Synthesis of Compound HT1-278

[0236]

[0237] Replacing AA-3, BB-3, and DD-3 sequentially with equimolar amounts of AA-278, BB-162, and DD-202, while adhering to the same steps as in Synthesis Example 1, yielded compound HT1-278 (17.14 g, 76% yield). HPLC analysis confirmed a solid purity ≥ 99.96%. Mass spectrometry m / z: 751.3261 (theoretical value: 751.3239). Theoretical elemental content (%) C 58 H 41 N: C, 92.64; H, 5.50; N, 1.86. Measured elemental content (%): C, 92.63; H, 5.52; N, 1.86.

[0238] Synthesis Example 17: Synthesis of Compound HT2-2

[0239]

[0240] Under nitrogen protection, aa-2 (9.44 g, 30 mmol), bb-2 (22.08 g, 90 mmol), sodium tert-butoxide (15.57 g, 162 mmol), and 300 mL of toluene were added to a reaction flask. While stirring, Pd2(dba)3 (0.83 g, 0.9 mmol) and a 0.5 M P(t-Bu)3 toluene solution (3.6 mL) were added. The mixture was heated under reflux for 5 h. After the reaction was complete, the mixture was cooled to room temperature, washed with distilled water, and then extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The residue was recrystallized from toluene / methanol (8:1 v / v) to give compound HT2-2 (19.15 g, 79%). HPLC analysis showed a solid purity ≥ 99.97%. Mass spectrometry m / z: 807.3623 (theoretical value: 807.3613). Theoretical element content (%) C 60 H 45 N3: C, 89.19; H, 5.61; N, 5.20. Measured elemental content (%): C, 89.17; H, 5.59; N, 5.24.

[0241] Synthesis Example 18: Synthesis of Compound HT2-10

[0242]

[0243] Under nitrogen protection, aa-10 (13.52 g, 50 mmol), bb-10 (16.92 g, 100 mmol), sodium tert-butoxide (17.3 g, 180 mmol), and 400 mL of toluene were added to a reaction flask. While stirring, Pd(dppf)Cl2 (0.73 g, 1 mmol) and a 0.5 M P(t-Bu)3 toluene solution (4 mL) were added. The mixture was heated under reflux for 4 h. After the reaction was complete, the mixture was cooled to room temperature, washed with distilled water, and then extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The residue was recrystallized from toluene / methanol (6:1 v / v) to give compound cc-10 (16.76 g, 75%). Mass spectrometry m / z: 446.1538 (theoretical value: 446.1550).

[0244] Under nitrogen protection, cc-10 (13.41 g, 30 mmol), dd-10 (9.64 g, 30 mmol), sodium tert-butoxide (5.29 g, 55 mmol), and 150 mL of toluene were added to a reaction flask. While stirring, Pd2(dba)3 (0.28 g, 0.3 mmol) and 1.2 mL of 0.5 M P(t-Bu)3 toluene solution were added. The mixture was heated under reflux for 4.5 h. After the reaction was complete, the mixture was cooled to room temperature, washed with distilled water, and then extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The residue was recrystallized from toluene / methanol (8:1 v / v) to give compound HT2-10 (15.81 g, 72%). HPLC analysis showed a solid purity ≥ 99.96%. Mass spectrometry m / z: 731.3319 (theoretical value: 731.3300). Theoretical element content (%) C 54 H 41 N3: C, 88.61; H, 5.65; N, 5.74. Measured elemental content (%): C, 88.65; H, 5.61; N, 5.74.

[0245] Synthesis Example 19: Synthesis of Compound HT2-32

[0246]

[0247] By replacing bb-10 and dd-10 with equimolar amounts of bb-32 and dd-32, respectively, and following the same steps as in Synthesis Example 18, compound HT2-32 (19.36 g, 73%) was obtained. HPLC analysis showed a solid purity ≥ 99.98%. Mass spectrometry m / z: 883.3905 (theoretical value: 883.3926). Theoretical elemental content (%) C 66 H 49 N3: C, 89.66; H, 5.59; N, 4.75. Measured elemental content (%): C, 89.68; H, 5.62; N, 4.72.

[0248] Synthesis Example 20: Synthesis of Compound HT2-37

[0249]

[0250] By replacing bb-10 and dd-10 with equimolar amounts of bb-2 and dd-37, respectively, and following the same steps as in Synthesis Example 18, compound HT2-37 (18.33 g, 76%) was obtained. HPLC analysis showed a solid purity ≥ 99.93%. Mass spectrometry m / z: 803.3684 (theoretical value: 803.3696). Theoretical elemental content (%) C 57 H 49N3Si: C, 85.14; H, 6.14; N, 5.23. Measured elemental content (%): C, 85.17; H, 6.15; N, 5.19.

[0251] Synthesis Example 21: Synthesis of Compound HT2-95

[0252]

[0253] Replacing dd-37 with an equimolar amount of dd-95, and following the same steps as in Synthesis Example 20, yielded compound HT2-95 (19.31 g, 72%). HPLC analysis showed a solid purity ≥ 99.96%. Mass spectrometry m / z: 893.4573 (theoretical value: 893.4554). Theoretical elemental content (%) C 66 H 39 D 10 N3: C, 88.65; H, 6.65; N, 4.70. Measured elemental content (%): C, 88.60; H, 6.68; N, 4.71.

[0254] Synthesis Example 22: Synthesis of Compound HT2-115

[0255]

[0256] Replacing bb-2 with an equimolar amount of bb-115, and following the same steps as in Synthesis Example 17, yielded compound HT2-115 (14.28 g, 80%). HPLC analysis showed a solid purity ≥ 99.95%. Mass spectrometry m / z: 594.3634 (theoretical value: 594.3616). Theoretical elemental content (%) C 42 H 18 D 15 N3: C, 84.81; H, 8.13; N, 7.06. Measured element content (%): C, 84.80; H, 8.17; N, 7.05.

[0257] Synthesis Example 23: Synthesis of Compound HT2-140

[0258]

[0259] Under nitrogen protection, aa-140 (25.39 g, 80 mmol), bb-10 (13.54 g, 80 mmol), sodium tert-butoxide (13.93 g, 145 mmol), and 450 mL of toluene were added to a reaction flask. While stirring, Pd(PPh3)4 (1.11 g, 0.96 mmol) and a 0.5 M toluene solution of P(t-Bu)3 (3 mL) were added. The mixture was heated under reflux for 3 h. After the reaction was complete, the mixture was cooled to room temperature, washed with distilled water, and then extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The residue was recrystallized from toluene / methanol (volume ratio 5:1) to give compound cc-140 (20.37 g, 71%). Mass spectrometry m / z: 356.9905 (theoretical value: 356.9920).

[0260] Under nitrogen protection, cc-140 (17.93 g, 50 mmol), bb-2 (12.27 g, 50 mmol), sodium tert-butoxide (9.13 g, 95 mmol), and 300 mL of toluene were added to a reaction flask. While stirring, Pd(dppf)Cl2 (0.44 g, 0.6 mmol) and a 0.5 M P(t-Bu)3 toluene solution (2 mL) were added. The mixture was heated under reflux for 4 h. After the reaction was complete, the mixture was cooled to room temperature, washed with distilled water, and then extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The residue was recrystallized from toluene / methanol (6:1 v / v) to give compound ee-140 (18.05 g, 69%). Mass spectrometry m / z: 523.0779 (theoretical value: 523.0760).

[0261] Under nitrogen protection, ee-140 (15.69 g, 30 mmol), dd-32 (9.64 g, 30 mmol), sodium tert-butoxide (5.29 g, 55 mmol), and 150 mL of toluene were added to a reaction flask. While stirring, Pd2(dba)3 (0.28 g, 0.3 mmol) and 1.2 mL of 0.5 M P(t-Bu)3 toluene solution were added. The mixture was heated under reflux for 4.5 h. After the reaction was complete, the mixture was cooled to room temperature, washed with distilled water, and then extracted with dichloromethane. The organic phase was dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by vacuum distillation. The residue was recrystallized from toluene / methanol (8:1 v / v) to give compound HT2-140 (16.97 g, 70%). HPLC analysis showed a solid purity ≥ 99.94%. Mass spectrometry m / z: 807.3601 (theoretical value: 807.3613). Theoretical element content (%) C 60 H 45N3: C, 89.19; H, 5.61; N, 5.20. Measured elemental content (%): C, 89.17; H, 5.65; N, 5.19.

[0262] Synthesis Example 24: Synthesis of Compound HT2-145

[0263]

[0264] Replacing bb-2 with an equimolar amount of bb-145, and following the same steps as in Synthesis Example 23, yielded compound HT2-145 (17.98 g, 71%). HPLC analysis showed a solid purity ≥ 99.93%. Mass spectrometry m / z: 843.4561 (theoretical value: 843.4552). Theoretical elemental content (%) C 62 H 57 N3: C, 88.22; H, 6.81; N, 4.98. Measured elemental content (%): C, 88.26; H, 6.83; N, 4.93.

[0265] Synthesis Example 25: Synthesis of Compound HT2-153

[0266]

[0267] By replacing aa-2 and bb-2 with equimolar amounts of aa-153 and bb-153, respectively, and following the same steps as in Synthesis Example 17, compound HT2-153 (17.58 g, 78%) was obtained. HPLC analysis showed a solid purity ≥ 99.93%. Mass spectrometry m / z: 750.4754 (theoretical value: 750.4741). Theoretical elemental content (%) C 54 H 54 D3N3: C, 86.35; H, 8.05; N, 5.59. Measured elemental content (%): C, 86.33; H, 8.04; N, 5.63.

[0268] Synthesis Example 26: Synthesis of Compound HT2-162

[0269]

[0270] Replacing aa-2 and bb-2 sequentially with equimolar amounts of aa-162 and bb-10, while adhering to the same steps as in Synthesis Example 17, yielded compound HT2-162 (13.99 g, 75%). HPLC analysis confirmed a solid purity ≥ 99.92%. Mass spectrometry m / z: 621.3160 ​​(theoretical value: 621.3144). Theoretical elemental content (%) C 45 H 39N3: C, 86.92; H, 6.32; N, 6.76. Measured elemental content (%): C, 86.94; H, 6.35; N, 6.71.

[0271] The following are other compounds used in the device fabrication examples besides those shown in formulas (I) and (II) of this invention:

[0272]

[0273] The organic materials used in the device fabrication examples were all purified by sublimation, with a purity of over 99.99%. The ITO glass substrates and ITO / Ag / ITO glass substrates used in the device fabrication examples were purchased commercially.

[0274] A combined IVL testing system was constructed, consisting of testing software, a computer, a Keithley K2400 digital source meter, and a Photo Research PR788 spectrophotometer. The device prepared according to this invention was tested at atmospheric pressure and room temperature at a current density of 15 mA / cm². 2 The luminous efficiency and driving voltage were measured. The lifetime (brightness decay to 95% of initial brightness) of the device prepared in this invention was tested using the McScience M6000 OLED lifetime testing system at atmospheric pressure and room temperature. The test results are shown in Tables 1 to 4.

[0275] Comparative device fabrication example 1: Comparative device 1

[0276] First, the ITO glass substrate is ultrasonically cleaned twice with deionized water for 20 minutes each time. Then, it is ultrasonically cleaned sequentially with isopropanol, acetone and methanol for 20 minutes each. After that, it is exposed to ultraviolet light and ozone for 30 minutes. Finally, it is placed in a vacuum evaporation equipment for later use.

[0277] The following layers are deposited layer by layer on the ITO glass substrate: a) HATCN as a hole injection layer with a thickness of 10 nm; b) HT1-55 as a first hole transport layer with a thickness of 50 nm; c) BANE and BD (mass ratio 97:3) as a light-emitting layer with a thickness of 30 nm; d) TPBi as a hole blocking layer with a thickness of 20 nm; e) HNBphen and Liq (mass ratio 3:2) as an electron transport layer with a thickness of 20 nm; f) LiF as an electron injection layer with a thickness of 1 nm; g) Al as a cathode with a thickness of 100 nm.

[0278] Comparative device fabrication examples 2-7: Comparative devices 2-7

[0279] By replacing HT1-55 in the first hole transport layer with HT1-60, HT1-207, HT1-259, HT2-2, HT2-95, and HT2-177 respectively, and following the same steps as in Comparative Device Preparation Example 1, Comparative Devices 2 to 7 can be obtained.

[0280] Device fabrication example 1: Device 1

[0281] First, the ITO glass substrate is ultrasonically cleaned twice with deionized water for 20 minutes each time. Then, it is ultrasonically cleaned sequentially with isopropanol, acetone and methanol for 20 minutes each. After that, it is exposed to ultraviolet light and ozone for 30 minutes. Finally, it is placed in a vacuum evaporation equipment for later use.

[0282] The following layers were deposited layer by layer on the ITO glass substrate: a) HATCN as a hole injection layer with a thickness of 10 nm; b) HT1-3 as a first hole transport layer with a thickness of 25 nm; c) HT2-10 as a light-emitting auxiliary layer with a thickness of 25 nm; d) BANE and BD (mass ratio 97:3) as a light-emitting layer with a thickness of 30 nm; e) TPBi as a hole blocking layer with a thickness of 20 nm; f) HNBphen and Liq (mass ratio 3:2) as an electron transport layer with a thickness of 20 nm; g) LiF as an electron injection layer with a thickness of 1 nm; h) Al as a cathode with a thickness of 100 nm.

[0283] Device fabrication example 2: Device 2

[0284] By replacing HT1-3 in the first hole transport layer with HT1-30 and HT2-10 in the light-emitting auxiliary layer with HT2-32, and following the same steps as in device fabrication example 1, device 2 can be obtained.

[0285] Device fabrication example 3: Device 3

[0286] Replace HT1-3 in the first hole transport layer with HT1-55, replace HT2-10 in the light-emitting auxiliary layer with HT2-2, and follow the same steps as in device fabrication example 1 to obtain device 3.

[0287] Device fabrication example 4: Device 4

[0288] Replace HT1-3 in the first hole transport layer with HT1-55, replace HT2-10 in the light-emitting auxiliary layer with HT2-115, and follow the same steps as in device fabrication example 1 to obtain device 4.

[0289] Device fabrication example 5: Device 5

[0290] Replace HT1-3 in the first hole transport layer with HT1-55, replace HT2-10 in the light-emitting auxiliary layer with HT2-145, and follow the same steps as in device fabrication example 1 to obtain device 5.

[0291] Device fabrication example 6: Device 6

[0292] Replace HT1-3 in the first hole transport layer with HT1-60, replace HT2-10 in the light-emitting auxiliary layer with HT2-95, and follow the same steps as in device fabrication example 1 to obtain device 6.

[0293] Device fabrication example 7: Device 7

[0294] Replace HT1-3 in the first hole transport layer with HT1-66, replace HT2-10 in the light-emitting auxiliary layer with HT2-2, and follow the same steps as in device fabrication example 1 to obtain device 7.

[0295] Device fabrication example 8: Device 8

[0296] Replace HT1-3 in the first hole transport layer with HT1-66, replace HT2-10 in the light-emitting auxiliary layer with HT2-162, and follow the same steps as in device fabrication example 1 to obtain device 8.

[0297] Device fabrication example 9: Device 9

[0298] Replace HT1-3 in the first hole transport layer with HT1-82, replace HT2-10 in the light-emitting auxiliary layer with HT2-140, and follow the same steps as in device fabrication example 1 to obtain device 9.

[0299] Device fabrication example 10: Device 10

[0300] Replace HT1-3 in the first hole transport layer with HT1-94, replace HT2-10 in the light-emitting auxiliary layer with HT2-115, and follow the same steps as in device fabrication example 1 to obtain device 10.

[0301] Device fabrication example 11: Device 11

[0302] Replace HT1-3 in the first hole transport layer with HT1-124, replace HT2-10 in the light-emitting auxiliary layer with HT2-37, and follow the same steps as in device fabrication example 1 to obtain device 11.

[0303] Device fabrication example 12: Device 12

[0304] By replacing HT1-3 in the first hole transport layer with HT1-142 and HT2-10 in the light-emitting auxiliary layer with HT2-2, and following the same steps as in device fabrication example 1, device 12 can be obtained.

[0305] Device fabrication example 13: Device 13

[0306] Replace HT1-3 in the first hole transport layer with HT1-162, replace HT2-10 in the light-emitting auxiliary layer with HT2-145, and follow the same steps as in device fabrication example 1 to obtain device 13.

[0307] Device fabrication example 14: Device 14

[0308] Replace HT1-3 in the first hole transport layer with HT1-202, replace HT2-10 in the light-emitting auxiliary layer with HT2-153, and follow the same steps as in device fabrication example 1 to obtain device 14.

[0309] Device fabrication example 15: Device 15

[0310] Replace HT1-3 in the first hole transport layer with HT1-207, replace HT2-10 in the light-emitting auxiliary layer with HT2-2, and follow the same steps as in device fabrication example 1 to obtain device 15.

[0311] Device fabrication example 16: Device 16

[0312] By replacing HT1-3 in the first hole transport layer with HT1-207 and HT2-10 in the light-emitting auxiliary layer with HT2-32, and following the same steps as in device fabrication example 1, device 16 can be obtained.

[0313] Device fabrication example 17: Device 17

[0314] Replace HT1-3 in the first hole transport layer with HT1-217, replace HT2-10 in the light-emitting auxiliary layer with HT2-115, and follow the same steps as in device fabrication example 1 to obtain device 17.

[0315] Device fabrication example 18: Device 18

[0316] By replacing HT1-3 in the first hole transport layer with HT1-241, and following the same steps as in Device Fabrication Example 1, device 18 can be obtained.

[0317] Device fabrication example 19: Device 19

[0318] By replacing HT1-3 in the first hole transport layer with HT1-259 and HT2-10 in the light-emitting auxiliary layer with HT2-140, and following the same steps as in device fabrication example 1, device 19 can be obtained.

[0319] Device fabrication example 20: Device 20

[0320] By replacing HT1-3 in the first hole transport layer with HT1-278 and HT2-10 in the light-emitting auxiliary layer with HT2-162, and following the same steps as in device fabrication example 1, device 20 can be obtained.

[0321] Table 1

[0322]

[0323]

[0324] Comparative device fabrication example 8: Comparative device 8

[0325] First, the ITO glass substrate is ultrasonically cleaned twice with deionized water for 20 minutes each time. Then, it is ultrasonically cleaned sequentially with isopropanol, acetone and methanol for 20 minutes each. After that, it is exposed to ultraviolet light and ozone for 30 minutes. Finally, it is placed in a vacuum evaporation equipment for later use.

[0326] The following layers were deposited layer by layer on the ITO glass substrate: a) 2-TNATA as a hole injection layer with a thickness of 50 nm; b) HT1-30 as a first hole transport layer with a thickness of 70 nm; c) RH-1, RH-2 and Ir(dpm)PQ2 (mass ratio 64:32:4) as a light-emitting layer with a thickness of 35 nm; d) TPBi as a hole blocking layer with a thickness of 25 nm; e) HNBphen and Liq (mass ratio 6:1) as an electron transport layer with a thickness of 25 nm; f) LiF as an electron injection layer with a thickness of 1 nm; g) Al as a cathode with a thickness of 100 nm.

[0327] Comparative device fabrication examples 9-12: Comparative devices 9-12

[0328] By replacing HT1-30 in the first hole transport layer with HT1-55, HT1-207, HT2-2, and HT2-95 respectively, and following the same steps as in Comparative Device Preparation Example 8, Comparative Devices 9 to 12 can be obtained.

[0329] Device fabrication example 21: Device 21

[0330] First, the ITO glass substrate is ultrasonically cleaned twice with deionized water for 20 minutes each time. Then, it is ultrasonically cleaned sequentially with isopropanol, acetone and methanol for 20 minutes each. After that, it is exposed to ultraviolet light and ozone for 30 minutes. Finally, it is placed in a vacuum evaporation equipment for later use.

[0331] The following layers were deposited layer by layer on the ITO glass substrate: a) 2-TNATA as a hole injection layer with a thickness of 50 nm; b) HT1-30 as a first hole transport layer with a thickness of 20 nm; c) HT1-60 as a second hole transport layer with a thickness of 25 nm; d) HT2-2 as a light-emitting auxiliary layer with a thickness of 25 nm; e) RH-1, RH-2 and Ir(dpm)PQ2 (mass ratio 64:32:4) as a light-emitting layer with a thickness of 35 nm; f) TPBi as a hole blocking layer with a thickness of 25 nm; g) HNBphen and Liq (mass ratio 6:1) as an electron transport layer with a thickness of 25 nm; h) LiF as an electron injection layer with a thickness of 1 nm; i) Al as a cathode with a thickness of 100 nm.

[0332] Device fabrication example 22: Device 22

[0333] By replacing HT1-60 in the second hole transport layer with HT1-94 and HT2-2 in the light-emitting auxiliary layer with HT2-95, and following the same steps as in device fabrication example 21, device 22 can be obtained.

[0334] Device fabrication example 23: Device 23

[0335] By replacing HT1-30 in the first hole transport layer with HT1-55, and following the same steps as in device fabrication example 21, device 23 can be obtained.

[0336] Device fabrication example 24: Device 24

[0337] By replacing HT1-30 in the first hole transport layer with HT1-55 and HT2-2 in the light-emitting auxiliary layer with HT2-115, and following the same steps as in device fabrication example 21, device 24 can be obtained.

[0338] Device fabrication example 25: Device 25

[0339] Replace HT1-30 in the first hole transport layer with HT1-55, replace HT1-60 in the second hole transport layer with HT1-259, and replace HT2-2 in the light-emitting auxiliary layer with HT2-32. All other steps are the same as in device fabrication example 21, and device 25 can be obtained.

[0340] Device fabrication example 26: Device 26

[0341] Replace HT1-30 in the first hole transport layer with HT1-82, replace HT1-60 in the second hole transport layer with HT1-3, and replace HT2-2 in the light-emitting auxiliary layer with HT2-140. All other steps are the same as in device fabrication example 21, and device 26 can be obtained.

[0342] Device fabrication example 27: Device 27

[0343] Replace HT1-30 in the first hole transport layer with HT1-124, replace HT1-60 in the second hole transport layer with HT1-217, and replace HT2-2 in the light-emitting auxiliary layer with HT2-37. All other steps are the same as in device fabrication example 21, and device 27 can be obtained.

[0344] Device fabrication example 28: Device 28

[0345] Replace HT1-30 in the first hole transport layer with HT1-162, replace HT1-60 in the second hole transport layer with HT1-241, and replace HT2-2 in the light-emitting auxiliary layer with HT2-32. All other steps are the same as in device fabrication example 21, and device 28 can be obtained.

[0346] Device fabrication example 29: Device 29

[0347] By replacing HT1-30 in the first hole transport layer with HT1-207 and HT2-2 in the light-emitting auxiliary layer with HT2-32, and following the same steps as in device fabrication example 21, device 29 can be obtained.

[0348] Device fabrication example 30: Device 30

[0349] Replace HT1-30 in the first hole transport layer with HT1-207, replace HT1-60 in the second hole transport layer with HT1-217, and replace HT2-2 in the light-emitting auxiliary layer with HT2-115. All other steps are the same as in device fabrication example 21, and device 30 can be obtained.

[0350] Device fabrication example 31: Device 31

[0351] Replace HT1-30 in the first hole transport layer with HT1-207, replace HT1-60 in the second hole transport layer with HT1-259, and replace HT2-2 in the light-emitting auxiliary layer with HT2-95. All other steps are the same as in device fabrication example 21, and device 31 can be obtained.

[0352] Table 2

[0353]

[0354] Comparative device fabrication example 13: Comparative device 13

[0355] First, the ITO / Ag / ITO glass substrate is ultrasonically cleaned twice with deionized water for 20 minutes each time. Then, it is ultrasonically cleaned sequentially with isopropanol, acetone and methanol for 20 minutes each. After that, it is exposed to ultraviolet light and ozone for 30 minutes. Finally, it is placed in a vacuum evaporation equipment for later use.

[0356] The following layers were deposited layer by layer on the aforementioned ITO / Ag / ITO glass substrate: a) HT1-30 and p-1 (mass ratio 20:1) as hole injection layer with a thickness of 20 nm; b) HT1-30 as first hole transport layer with a thickness of 65 nm; c) GH-1, GH-2 and Ir(ppy)2(m-bppy) (mass ratio 48:48:4) as light-emitting layer with a thickness of 35 nm; d) BAlq as hole blocking layer with a thickness of 35 nm; e) HNBphen and Liq (mass ratio 7:1) as electron transport layer with a thickness of 20 nm; f) LiF as electron injection layer with a thickness of 0.1 nm; g) Mg and Ag (mass ratio 7:3) as cathode with a thickness of 10 nm; h) CP-4 as capping layer with a thickness of 100 nm.

[0357] Comparative device fabrication examples 14-18: Comparative devices 14-18

[0358] By replacing HT1-30 in the hole injection layer and the first hole transport layer with HT1-55, HT1-207, HT2-2, HT2-32, and HT2-115 respectively, and following the same steps as in Comparative Device Preparation Example 13, Comparative Devices 14 to 18 can be obtained.

[0359] Device fabrication example 32: Device 32

[0360] First, the ITO / Ag / ITO glass substrate is ultrasonically cleaned twice with deionized water for 20 minutes each time. Then, it is ultrasonically cleaned sequentially with isopropanol, acetone and methanol for 20 minutes each. After that, it is exposed to ultraviolet light and ozone for 30 minutes. Finally, it is placed in a vacuum evaporation equipment for later use.

[0361] The following layers are deposited sequentially on the aforementioned ITO / Ag / ITO glass substrate: a) HT1-30 and p-1 (mass ratio 20:1) as hole injection layers, with a thickness of 20 nm; b) HT1-30 as the first hole transport layer, with a thickness of 20 nm; c) HT2-2 as the light-emitting auxiliary layer, with a thickness of 25 nm; d) HT1-60 as the second hole transport layer, with a thickness of 20 nm; e) GH-1, GH-2 and Ir(ppy)2(m f, BAlq (mass ratio 48:48:4) are used as the light-emitting layer with a thickness of 35 nm; g, HNBphen and Liq (mass ratio 7:1) are used as the electron transport layer with a thickness of 20 nm; h, LiF is used as the electron injection layer with a thickness of 0.1 nm; i, Mg and Ag (mass ratio 7:3) are used as the cathode with a thickness of 10 nm; j, CP-4 is used as the capping layer with a thickness of 100 nm.

[0362] Device fabrication example 33: Device 33

[0363] By replacing HT2-2 in the light-emitting auxiliary layer with HT2-145 and HT1-60 in the second hole transport layer with HT1-217, and following the same steps as in device fabrication example 32, device 33 can be obtained.

[0364] Device fabrication example 34: Device 34

[0365] By replacing HT1-30 in the hole injection layer and the first hole transport layer with HT1-55, and replacing HT1-60 in the second hole transport layer with HT1-66, and following the same steps as in device fabrication example 32, device 34 can be obtained.

[0366] Device fabrication example 35: Device 35

[0367] Replace HT1-30 in the hole injection layer and the first hole transport layer with HT1-55, replace HT2-2 in the light emission auxiliary layer with HT2-115, and replace HT1-60 in the second hole transport layer with HT1-217. All other steps are the same as in device fabrication example 32, and device 35 can be obtained.

[0368] Device fabrication example 36: Device 36

[0369] Replace HT1-30 in the hole injection layer and the first hole transport layer with HT1-124, replace HT2-2 in the light emission auxiliary layer with HT2-32, and replace HT1-60 in the second hole transport layer with HT1-217. All other steps are the same as in device fabrication example 32, and device 36 can be obtained.

[0370] Device fabrication example 37: Device 37

[0371] By replacing HT1-30 in the hole injection layer and the first hole transport layer with HT1-207, and replacing HT2-2 in the light-emitting auxiliary layer with HT2-95, and following the same steps as in device fabrication example 32, device 37 can be obtained.

[0372] Device fabrication example 38: Device 38

[0373] Replace HT1-30 in the hole injection layer and the first hole transport layer with HT1-207, replace HT2-2 in the light emission auxiliary layer with HT2-115, and replace HT1-60 in the second hole transport layer with HT1-94. All other steps are the same as in device fabrication example 32, and device 38 can be obtained.

[0374] Device fabrication example 39: Device 39

[0375] Replace HT1-30 in the hole injection layer and the first hole transport layer with HT1-278, replace HT2-2 in the light emission auxiliary layer with HT2-95, and replace HT1-60 in the second hole transport layer with HT1-66. All other steps are the same as in device fabrication example 32, and device 39 can be obtained.

[0376] Table 3

[0377]

[0378] Comparative device fabrication example 19: Comparative device 19

[0379] First, the ITO / Ag / ITO glass substrate is ultrasonically cleaned twice with deionized water for 20 minutes each time. Then, it is ultrasonically cleaned sequentially with isopropanol, acetone and methanol for 20 minutes each. After that, it is exposed to ultraviolet light and ozone for 30 minutes. Finally, it is placed in a vacuum evaporation equipment for later use.

[0380] The following layers were deposited layer by layer on the aforementioned ITO / Ag / ITO glass substrate: a) HT1-30 and p-1 (mass ratio 20:1) as a hole injection layer with a thickness of 25 nm; b) HT1-30 as a first hole transport layer with a thickness of 100 nm; c) RH-1, RH-3 and Ir(dpm)(piq)2 (mass ratio 48:48:4) as a light-emitting layer with a thickness of 35 nm; d) TPBi as a hole blocking layer with a thickness of 25 nm; e) HNBphen and Liq (mass ratio 9:1) as an electron transport layer with a thickness of 20 nm; f) LiF as an electron injection layer with a thickness of 0.1 nm; g) Mg and Ag (mass ratio 7:3) as a cathode with a thickness of 10 nm; h) CP-4 as a capping layer with a thickness of 100 nm.

[0381] Comparative device fabrication examples 20-24: Comparative devices 20-24

[0382] By replacing HT1-30 in the hole injection layer and the first hole transport layer with HT1-55, HT1-207 and HT2-2 respectively, and taking the same steps as in Comparative Device Preparation Example 19, Comparative Devices 20 to 24 can be obtained.

[0383] Device fabrication example 40: Device 40

[0384] First, the ITO / Ag / ITO glass substrate is ultrasonically cleaned twice with deionized water for 20 minutes each time. Then, it is ultrasonically cleaned sequentially with isopropanol, acetone and methanol for 20 minutes each. After that, it is exposed to ultraviolet light and ozone for 30 minutes. Finally, it is placed in a vacuum evaporation equipment for later use.

[0385] The following layers were deposited sequentially on the aforementioned ITO / Ag / ITO glass substrate: a) HT1-30 and p-1 (mass ratio 20:1) as a hole injection layer with a thickness of 25 nm; b) HT1-30 as a first hole transport layer with a thickness of 30 nm; c) HT1-66 as a second hole transport layer with a thickness of 20 nm; d) HT2-2 as a light-emitting auxiliary layer with a thickness of 30 nm; e) HT1-60 as a third hole transport layer with a thickness of 20 nm; f) RH-1... RH-3 and Ir(dpm)(piq)2 (mass ratio 48:48:4) are used as the light-emitting layer with a thickness of 35 nm; g and TPBi are used as the hole blocking layer with a thickness of 25 nm; h, HNBphen and Liq (mass ratio 9:1) are used as the electron transport layer with a thickness of 20 nm; i and LiF are used as the electron injection layer with a thickness of 0.1 nm; j, Mg and Ag (mass ratio 7:3) are used as the cathode with a thickness of 10 nm; k:CP-4 is used as the capping layer with a thickness of 100 nm.

[0386] Device fabrication example 41: Device 41

[0387] Replace HT1-66 in the second hole transport layer with HT1-94, replace HT2-2 in the light-emitting auxiliary layer with HT2-10, and replace HT1-60 in the third hole transport layer with HT1-217. All other steps are the same as in device fabrication example 40, and device 41 can be obtained.

[0388] Device fabrication example 42: Device 42

[0389] Replace HT1-30 in the first hole transport layer with HT1-55, replace HT1-66 in the second hole transport layer with HT1-3, replace HT2-2 in the light-emitting auxiliary layer with HT2-32, and replace HT1-60 in the third hole transport layer with HT1-217. All other steps are the same as in device fabrication example 40, and device 42 can be obtained.

[0390] Device fabrication example 43: Device 43

[0391] Replace HT1-30 in the first hole transport layer with HT1-55, replace HT1-66 in the second hole transport layer with HT1-202, and replace HT2-2 in the light-emitting auxiliary layer with HT2-115. All other steps are the same as in device fabrication example 40, and device 43 can be obtained.

[0392] Device fabrication example 44: Device 44

[0393] Replace HT1-30 in the first hole transport layer with HT1-55, replace HT1-66 in the second hole transport layer with HT1-259, and replace HT2-2 in the light-emitting auxiliary layer with HT2-95. All other steps are the same as in device fabrication example 40, and device 44 can be obtained.

[0394] Device fabrication example 45: Device 45

[0395] Replace HT1-30 in the first hole transport layer with HT1-124, replace HT1-66 in the second hole transport layer with HT1-241, replace HT2-2 in the light-emitting auxiliary layer with HT2-37, and replace HT1-60 in the third hole transport layer with HT1-3. All other steps are the same as in device fabrication example 40, and device 45 can be obtained.

[0396] Device fabrication example 46: Device 46

[0397] By replacing HT1-30 in the first hole transport layer with HT1-207 and HT1-60 in the third hole transport layer with HT1-217, and following the same steps as in device fabrication example 40, device 46 can be obtained.

[0398] Device fabrication example 47: Device 47

[0399] Replace HT1-30 in the first hole transport layer with HT1-207, replace HT1-66 in the second hole transport layer with HT1-259, and replace HT2-2 in the light-emitting auxiliary layer with HT2-115. All other steps are the same as in device fabrication example 40, and device 47 can be obtained.

[0400] Device fabrication example 48: Device 48

[0401] Replace HT1-30 in the first hole transport layer with HT1-207, replace HT1-66 in the second hole transport layer with HT1-60, replace HT2-2 in the light-emitting auxiliary layer with HT2-95, and replace HT1-60 in the third hole transport layer with HT1-217. All other steps are the same as in device fabrication example 40, and device 48 can be obtained.

[0402] Device fabrication example 49: Device 49

[0403] By replacing HT1-30 in the first hole transport layer with HT1-241 and HT2-2 in the light-emitting auxiliary layer with HT2-162, and following the same steps as in device fabrication example 40, device 49 can be obtained.

[0404] Table 4

[0405]

[0406]

[0407] The device data in Tables 1 to 4 show that the organic electroluminescent device of the present invention utilizes a hole transport region with a specific structure to enable the device to have excellent driving voltage, luminous efficiency and lifespan performance.

[0408] It should be noted that the present invention has been specifically described with reference to individual embodiments, but those skilled in the art can make various forms or details of improvements to the present invention without departing from the principles of the present invention, and these improvements also fall within the protection scope of the present invention.

Claims

1. An organic electroluminescent device, comprising an anode, a cathode, and an organic layer, wherein the organic layer is located between the anode and the cathode, the organic layer comprising a hole transport region, a light-emitting layer, and an electron transport region, the hole transport region comprising a first hole transport layer and a light-emitting auxiliary layer, the first hole transport layer being located between the anode and the light-emitting layer, and the light-emitting auxiliary layer being located between the first hole transport layer and the light-emitting layer, characterized in that, The first hole transport layer contains one of the compounds shown in formula (I), and the light-emitting auxiliary layer contains one of the compounds shown in formula (II). In formula (I), Ar1 and Ar2 are independently selected from one of the following structures: Wherein, each time a1 appears, it is selected from 0, 1, 2, 3 or 4, the same or different; each time b1 appears, it is selected from 0, 1, 2 or 3, the same or different; each time c1 appears, it is selected from 0, 1, 2, 3, 4 or 5, the same or different. R1 and R2 are independently selected from hydrogen atoms, deuterium atoms, halogen atoms, cyano groups, and substituted or substituted C1-C12 alkyl groups; Each time R3 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring. Two adjacent R3s can be linked to form one of the following: a substituted or unsubstituted C3-C7 aliphatic ring or a substituted or unsubstituted C6-C10 aromatic ring. The Ar3 is selected from one of the following: a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aromatic ring fused with a C3-C7 aliphatic ring; The L1 to L3 are independently selected from one of the following: a single bond, a substituted or unsubstituted C6 to C30 arylene group, or a divalent group formed by the fusion of a substituted or unsubstituted C6 to C30 aromatic ring and a C3 to C7 aliphatic ring; In equation (II), the a 101 Choose from 0, 1, 2, or 3; The R mentioned 101 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, substituted or unsubstituted C3-C30 heteroaryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring. The Ar 101 ~Ar 106 Independently selected from one of the following structures: Wherein, the a 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, or 5, either identically or differently; the b mentioned 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either identically or differently; c 102 Each time it appears, it is selected from 0, 1, 2, or 3, either identically or differently; the d mentioned 102 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different. The R mentioned 102 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted phenyl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring. The R mentioned 103 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1 to C12 alkyl group; The L mentioned 101 ~L 106 Independently selected from a single bond or one of the following structures: Wherein, the a 103 Each time it appears, it is selected from 0, 1, 2, 3, or 4, either identically or differently; the b mentioned 103 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either identically or differently; c 103 Each time it appears, it is selected from 0, 1, or 2, either identically or differently; the d mentioned 103 Each time it appears, it is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different. The R mentioned 104 Each time it appears, it is selected from one of the following, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, or phenyl group substituted or unsubstituted by deuterium atom. The R mentioned 105 Each time it appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1 to C12 alkyl group.

2. The organic electroluminescent device according to claim 1, characterized in that, The Ar3 is selected from one of the following structures: Wherein, each occurrence of a3 is selected from 0, 1, 2, 3, 4, or 5, either the same or different; each occurrence of b3 is selected from 0, 1, 2, 3, or 4, either the same or different; each occurrence of c3 is selected from 0, 1, 2, or 3, either the same or different; each occurrence of d3 is selected from 0, 1, or 2, either the same or different; each occurrence of e3 is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different; and each occurrence of f3 is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either the same or different. Each time R6 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring. Each time R7 appears, it is selected from one of hydrogen atoms, deuterium atoms, halogen atoms, cyano groups, substituted or unsubstituted C1 to C12 alkyl groups, either the same or different.

3. The organic electroluminescent device according to claim 1, characterized in that, The L1 to L3 are independently selected from a single bond or one of the following structures: Wherein, each occurrence of a2 is selected from 0, 1, 2, 3, or 4, either the same or different; each occurrence of b2 is selected from 0, 1, 2, or 3, either the same or different; each occurrence of c2 is selected from 0, 1, or 2, either the same or different; each occurrence of d2 is selected from 0, 1, 2, 3, 4, 5, or 6, either the same or different; and each occurrence of e2 is selected from 0, 1, 2, 3, 4, 5, 6, 7, or 8, either the same or different. Each time R4 appears, it is selected from one of the following groups, either the same or different: hydrogen atom, deuterium atom, halogen atom, cyano group, substituted or unsubstituted C1-C12 alkyl group, substituted or unsubstituted C3-C10 cycloalkyl group, substituted or unsubstituted silyl group, substituted or unsubstituted C6-C30 aryl group, or a group formed by fusion of a substituted or unsubstituted C6-C30 aromatic ring and a C3-C7 aliphatic ring. Each time R5 appears, it is selected from one of hydrogen atoms, deuterium atoms, halogen atoms, cyano groups, substituted or unsubstituted C1 to C12 alkyl groups, either the same or different.

4. The organic electroluminescent device according to claim 1, characterized in that, The compound represented by formula (I) is selected from one of the following compounds:

5. The organic electroluminescent device according to claim 1, characterized in that, The compound represented by formula (II) is selected from one of the following compounds:

6. The organic electroluminescent device according to claim 1, wherein the hole transport region further comprises a second hole transport layer, the second hole transport layer being located between the first hole transport layer and the light-emitting auxiliary layer, characterized in that, The second hole transport layer contains one of the compounds shown in formula (I), and is different from the compound in the first hole transport layer.

7. The organic electroluminescent device according to claim 1, wherein the hole transport region further comprises a second hole transport layer, the second hole transport layer being located between the light-emitting auxiliary layer and the light-emitting layer, characterized in that, The second hole transport layer contains one of the compounds shown in formula (I), and is different from the compound in the first hole transport layer.

8. The organic electroluminescent device according to claim 6, wherein the hole transport region further comprises a third hole transport layer, the third hole transport layer being located between the light-emitting auxiliary layer and the light-emitting layer, characterized in that, The third hole transport layer contains one of the compounds shown in formula (I), and is different from the compound in the first hole transport layer and different from the compound in the second hole transport layer.

9. The organic electroluminescent device according to any one of claims 1 to 8, characterized in that, The light-emitting auxiliary layer is a single-layer structure composed of a single substance, which is the compound shown in formula (II).

10. The organic electroluminescent device according to any one of claims 1 to 8, characterized in that, The light-emitting auxiliary layer is a bilayer structure composed of two substances, both of which are selected from the compounds shown in formula (II), and the two substances are different compounds.

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