Composition of bicarbazole compounds containing para-biphenyl substituents and organic electroluminescent device containing the same

Abstract

The present invention provides a composition of a bicarbazole compound containing a para-biphenyl substituent and an organic electroluminescent device containing the same. The composition comprises a first host compound and a second host compound, wherein the first host compound has a structure shown in the following formula I, and the second host compound has a structure shown in the following formula II. The composition provided by the present invention is used as a material for a light-emitting layer of an organic electroluminescent device, and the prepared OLED device has a lower driving voltage, a higher current efficiency and a longer lifespan.

Description

Technical Field

[0001] The invention belongs to the technical field of organic electroluminescent materials, and in particular relates to a composition of bicarbazole compounds containing a para-biphenyl substituent and an organic electroluminescent device containing the composition. Background Art

[0002] Currently, organic electroluminescent (OLED) display technology has been applied in smart phones, tablet computers and other fields, and will be further expanded to large-size application fields such as televisions. In the past 30 years of development, people have developed various OLED materials with excellent performance, and through different designs of device structures and optimization of device performance such as life and efficiency, the commercialization process of OLED has been accelerated, making OLED widely used in the display and lighting fields.

[0003] The selection of materials for the hole layer, light-emitting layer and other organic functional layers also has a significant impact on the current efficiency, driving voltage and life of the device. Currently, we are still exploring functional layer materials with higher performance.

[0004] Therefore, in order to meet people's higher requirements for OLED devices, the field is in urgent need of developing more types of OLED materials with higher performance. Summary of the invention

[0005] In view of the shortcomings of the prior art, the object of the present invention is to provide a composition of a bicarbazole compound containing a para-biphenyl substituent and an organic electroluminescent device containing the same. In the present invention, by designing the specific composition of the composition and the structures of the first host compound and the second host compound, the composition is used as the material of the light-emitting layer of the organic electroluminescent device, and the prepared OLED device has a lower driving voltage, a higher current efficiency and a longer life.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a composition of a bicarbazole compound containing a para-biphenyl substituent, the composition comprising a first main compound and a second main compound, the first main compound having a structure as shown in the following formula I, and the second main compound having a structure as shown in the following formula II:

[0008]

[0009] Wherein, Y is selected from O, S, Any one of R 101 , R 102 Each independently selected from methyl (-CH3) or deuterated methyl (-CD3), R 103 Selected from phenyl or deuterated phenyl Dashed lines indicate junction sites;

[0010] a, h, i, j are each independently selected from 0 or 5, b, d, f, g, k, l, n are each independently selected from 0 or 4, c, e are each independently selected from 0 or 3, m is selected from 0 or 2, and ah is not 0 at the same time;

[0011] The Y is selected from O and S, and the in is not 0 at the same time.

[0012] In the present invention, by designing the specific composition of the composition and the structures of the first host compound and the second host compound, the composition is used as the material of the light-emitting layer of the organic electroluminescent device, and the prepared OLED device has a lower driving voltage, a higher current efficiency and a longer life.

[0013] In the present invention, the structure of the first main compound is designed to contain two biphenyl groups, and one of them is selected to be a para-biphenyl group. If the other biphenyl group is an ortho-biphenyl group or a meta-biphenyl group, the composition has good film-forming properties, and the organic electroluminescent device prepared thereby has a longer lifespan; if the other biphenyl group is also a para-biphenyl group, the driving voltage of the organic electroluminescent device can be further reduced, thereby improving the current efficiency of the organic electroluminescent device.

[0014] It should be noted that in the structures represented by the above formula I and formula II, D is a deuterium atom (the same below).

[0015] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0016] As a preferred technical solution of the present invention, the first main compound has a structure shown in the following formula I-1 or formula I-2:

[0017]

[0018] As a preferred technical solution of the present invention, the first main compound is selected from any one of compounds H-1 to H-6:

[0019]

[0020]

[0021] As a preferred technical solution of the present invention, the second main compound has a structure shown in the following formula II-1 or formula II-2:

[0022]

[0023] As a preferred technical solution of the present invention, the second host is selected from any one of compounds E-1 to E-17:

[0024]

[0025]

[0026] Preferably, the second host is selected from the following compounds:

[0027]

[0028] In a second aspect, the present invention provides a compound comprising:

[0029]

[0030]

[0031] The compound is used to prepare the composition as described in the first aspect.

[0032] It should be noted that, in the above compounds, D is a deuterium atom and -CD3 is a deuterated methyl group.

[0033] The third invention, the present invention provides an intermediate, the intermediate includes the following compounds:

[0034]

[0035] The intermediate is used to prepare the second main compound in the composition as described in the first aspect.

[0036] It should be noted that, in the above intermediate, D is a deuterium atom and -CD3 is a deuterated methyl group.

[0037] It should be noted that the present invention does not impose any special restrictions on the preparation method of the first main compound or the second main compound, and they can be prepared by conventional methods in the art.

[0038] In a fourth aspect, the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising an anode, a cathode and an organic thin film layer disposed between the anode and the cathode;

[0039] The material of the organic thin film layer includes the composition described in the first aspect.

[0040] Preferably, the organic thin film layer includes a light-emitting layer.

[0041] The material of the light-emitting layer includes the composition described in the first aspect.

[0042] As a preferred technical solution of the present invention, the organic thin film layer includes a hole layer.

[0043] Preferably, the hole layer comprises an electron blocking layer, and the material of the electron blocking layer comprises a spirofluorene compound;

[0044] The spirofluorene compound has a structure as shown in the following formula III:

[0045]

[0046] wherein X is selected from O or S;

[0047] R 11 , R 21 Each is independently selected from hydrogen, deuterium, fluorine, CN, substituted or unsubstituted C1-C20 (for example, C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18 or C20, etc.) straight or branched alkyl, substituted or unsubstituted C1-C20 (for example, C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18 or C20, etc.) alkoxy, substituted or unsubstituted C6-C40 (for example, C6, C8, C10, C12, C15, C18, C24, C30, C36 or C40, etc.) aryl;

[0048] Ar is selected from substituted or unsubstituted C6-C40 (e.g., C6, C8, C10, C12, C15, C18, C24, C30, C36 or C40, etc.) arylene;

[0049] Ar1 and Ar2 are each independently selected from substituted or unsubstituted C6-C40 (for example, C6, C8, C10, C12, C15, C18, C24, C30, C36 or C40, etc.) aryl, substituted or unsubstituted C12-C40 (C12, C14, C16, C18, C20, C23, C25, C27, C30, C32, C35, C37, C39 or C40, etc.) oxoaryl, substituted or unsubstituted C12-C40 (C12, C14, C16, C18, C20, C23, C25, C27, C30, C32, C35, C37, C39 or C40, etc.) thioaryl, and at least one of Ar1 or Ar2 is selected from any one of phenyl, naphthyl, triphenylene or fluoranthenyl; p is selected from 0 or 1;

[0050] m and n are each independently selected from integers of 0 to 4, and may be, for example, 0, 1, 2, 3, or 4.

[0051] It should be noted that the oxygen heteroaryl group refers to a structure having an oxygen-containing five-membered heterocyclic ring formed by two aromatic rings connected by a single bond and bridged by an O atom. For example, two benzene rings are connected by a single bond to form biphenyl, and the carbon atoms on the two benzene rings constituting the biphenyl are simultaneously connected to O atoms to form dibenzofuran.

[0052] The sulfur heteroaryl group refers to a structure having a sulfur-containing five-membered heterocyclic ring formed by two aromatic rings connected by a single bond and bridged by an S atom. For example, two benzene rings are connected by a single bond to form biphenyl, and the carbon atoms on the two benzene rings constituting the biphenyl are simultaneously connected to S atoms to form dibenzothiophene.

[0053] Preferably, the spirofluorene compound is selected from the compound shown in III-1 or the compound shown in III-2:

[0054]

[0055] Wherein, X and X1 are each independently selected from O or S;

[0056] R 11 , R 21 , Ar has the same protection scope as above;

[0057] Ar1 is selected from any one of phenyl, naphthyl, triphenylene or fluoranthenyl;

[0058] R 31 selected from C1-C20 (e.g., C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18, or C20, etc.) straight or branched alkyl, C1-C20 (e.g., C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18, or C20, etc.) alkoxy, C6-C40 (e.g., C6, C8, C10, C12, C15, C18, C24, C30, C36, or C40, etc.) aryl;

[0059] R 41 , R 42 Each is independently selected from C1-C20 (e.g., C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18, or C20, etc.) straight chain or branched chain alkyl, C6-C40 (e.g., C6, C8, C10, C12, C15, C18, C24, C30, C36, or C40, etc.) aryl, and R 41 and R 42 They are independent of each other or connected to form a ring through single bonds.

[0060] Preferably, the spirofluorene compound is selected from any one of the following compounds 1-140 and compounds 1S-140S:

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070] The compound 1S-140S is a compound 1-140 Replace with The dotted lines indicate the connection sites.

[0071] For example, the structure of compound 2 is Then the structure of compound 2S is:

[0072] In a fifth aspect, the present invention provides a display device, comprising the organic electroluminescent device as described in the fourth aspect.

[0073] Compared with the prior art, the present invention has the following beneficial effects:

[0074] In the present invention, by designing the specific composition of the composition and the structures of the first host compound and the second host compound, and further selecting at least one of the two biphenyl groups in the first host compound as a para-biphenyl group, a composition with a specific composition is obtained. The composition is used as a material for the light-emitting layer of an organic electroluminescent device, and the prepared OLED device has a lower driving voltage, a higher current efficiency and a longer life. DETAILED DESCRIPTION

[0075] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0076] Preparation Example 1

[0077] This preparation example provides an intermediate E-7-2 and a synthesis method thereof, the synthesis method is as follows:

[0078]

[0079] At room temperature, 12,12-dimethyl-11,12-dihydroindeno[2,1-a]carbazole (5 g), palladium chloride (0.034 g), activated carbon (0.2 g), D2O (25 mL) and C6D6 (100 mL) were added to a 500 mL autoclave, and hydrogen was introduced to a pressure of 0.02 MPa. The temperature was then raised to 90°C for reaction for 120 hours, and the temperature was lowered to room temperature, filtered, and separated. The organic layer after separation was dried over magnesium sulfate, decolorized with a short silica gel column, concentrated to dryness, and recrystallized from ethanol to obtain 4.6 g of the intermediate shown in E-7-2.

[0080] The obtained intermediate E-7-2 was subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) was measured to be 294.21.

[0081] The intermediate E-7-2 was subjected to hydrogen nuclear magnetic resonance analysis to obtain 1H-NMR (Bruker, Switzerland, AvanceⅡ400MHz nuclear magnetic resonance spectrometer, CDCl3), which showed only a single peak at δ1.70 and no other peaks.

[0082] Preparation Example 2

[0083] This preparation example provides an intermediate E-11-2 and a synthesis method thereof, the synthesis method is as follows:

[0084]

[0085] At room temperature, 12,12-dimethyl-11,12-dihydroindeno[2,1-a]carbazole (5 g), palladium chloride (0.034 g), anhydrous nickel chloride (0.026 g), activated carbon (0.2 g), D2O (25 mL) and C6D6 (100 mL) were added to a 500 mL autoclave, and hydrogen was introduced to a pressure of 0.02 MPa. The temperature was then raised to 90°C for reaction for 80 hours, and the temperature was lowered to room temperature, filtered, and separated. The organic layer after separation was dried over magnesium sulfate, decolorized with a short silica gel column, concentrated to dryness, and recrystallized from ethanol to obtain 4.7 g of the intermediate shown in E-11-2.

[0086] The obtained intermediate E-11-2 was subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) was 300.24.

[0087] The obtained intermediate E-11-2 was subjected to hydrogen spectrum nuclear magnetic resonance analysis to obtain 1 H-NMR (Bruker, Switzerland, AvanceⅡ400MHz nuclear magnetic resonance spectrometer, CDCl3), no H peak.

[0088] Preparation Example 3

[0089] This preparation example provides an intermediate E-9-2 and a synthesis method thereof, the synthesis method is as follows:

[0090]

[0091] (1) Under nitrogen protection, add 100 mL of tetrahydrofuran and 1-bromo-2-phenylcarbazole (3.2 g, 0.01 mol) to a 500 mL three-necked flask, cool to -78°C, slowly add dropwise a 1.6 M solution of butyl lithium in n-hexane (13.8 mL, 0.022 mol), maintain at -78°C for 30 min after the addition, slowly add deuterated acetone (1.92 g, 0.03 mol), maintain at -78 to -60°C for 30 min, slowly warm to room temperature, add water and dichloromethane for separation, wash the organic layer with water, dry with magnesium sulfate, filter out the magnesium sulfate, and obtain a dichloromethane solution of E-9-2-1.

[0092] (2) The dichloromethane solution of E-9-2-1 was cooled to 0°C and 5 mL of trifluoromethanesulfonic acid was slowly added dropwise. During the addition, solids gradually precipitated. After the addition was completed, the temperature was slowly raised to room temperature and the reaction was continued for 2 h. The solids were filtered and washed with water and methanol to obtain 1.7 g of intermediate E-9-2.

[0093] The obtained intermediate E-9-2 was subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) was 289.17.

[0094] The obtained intermediate E-9-2 was subjected to nuclear magnetic resonance detection: 1H-NMR (Bruker Company, Switzerland, AvanceⅡ400MHz nuclear magnetic resonance spectrometer, CDCl3), δ8.25 (m, 1H), δ8.21 (m, 1H), δ7.77 (d, 1H), δ7.65 (m, 1H), δ7.55~7.50 (m, 2H), δ7.42~7.39 (m, 2H), δ7.29 (m, 1H), δ7.22~7.19 (m, 2H).

[0095] Example 1

[0096] This example provides compound H-3 and its synthesis method, the synthesis method is as follows:

[0097]

[0098] Under nitrogen protection, 100L of dry toluene, intermediate H-3-1 (5.0g), 2-bromobiphenyl (2.4g), Pd(dba)2 (bis(dibenzylideneacetonepalladium, 0.0575g), 10% tri-tert-butylphosphine toluene solution (the mass of tri-tert-butylphosphine solution is 0.8g, the amount of tri-tert-butylphosphine is 0.0004mol) and sodium tert-butoxide (1.44g) were added to a 250L three-necked flask, heated to reflux for reaction for 8 hours, cooled to room temperature and then water was added to separate, then the organic layer was washed with water until neutral, dried with magnesium sulfate, filtered to remove magnesium sulfate, concentrated to dryness, and crystallized from toluene to obtain compound H-3 (4.8g)

[0099] The mass spectrometry of compound H-3 was performed: the mass-to-charge ratio (m / z) was measured to be 650.34.

[0100] Example 2-12

[0101] Examples 2-12 respectively provide a compound and a synthesis method thereof. Reactant 1 and reactant 2 undergo a synthesis reaction to obtain the corresponding compound. The synthesis method refers to the synthesis method provided in Example 1. The structures of the specific reactants and the prepared compounds are detailed in Table 1.

[0102] The synthesized compounds were detected by mass spectrometry, and the mass-to-charge ratios (m / z) are shown in Table 1.

[0103] Table 1

[0104]

[0105]

[0106]

[0107] Other compounds whose specific synthesis steps are not listed can be prepared by common knowledge in the art in combination with the above embodiments.

[0108] The specific structures of the compounds used in the following device application examples and device comparative examples are as follows:

[0109]

[0110] Device Application Example 1

[0111] Application example 1 of the device provides an organic electroluminescent device, and the composition provided by the present invention is selected as the red light main material in the organic electroluminescent device.

[0112] The structure of the organic electroluminescent device is: ITO / HT-1 (20nm) / red light host material (35nm): Ir(piq)3[10%] / TPBI(10nm) / Alq3(15nm) / LiF(0.5nm) / Al(150nm). "Ir(piq)3[10%]" refers to the doping ratio of the red light dye, that is, the volume ratio of the red light host material to Ir(piq)3 is 90:10.

[0113] The organic electroluminescent device preparation process is as follows:

[0114] (1) a glass plate coated with an ITO transparent conductive layer was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in an acetone:ethanol mixed solvent, baked in a clean environment until the water was completely removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam;

[0115] (2) Place the glass substrate with the anode in a vacuum chamber and evacuate the chamber to a vacuum of 1×10 -5 ~9×10 -4 Pa, vacuum evaporating a hole transport layer HT-1 on the above anode layer film, the evaporation rate is 0.1nm / s, and the evaporation film thickness is 20nm;

[0116] (3) Vacuum-evaporating a red light host material and dye Ir(piq)3 on the hole transport layer as the light-emitting layer of the organic electroluminescent device, with an evaporation rate of 0.1 nm / s and a total evaporation film thickness of 35 nm; in the application example of this device, the first host compound H-1 and the second host compound E-1 are placed in different evaporation sources for heating, and the heating rate is controlled so that the volume ratio of the two evaporated onto the substrate is 1:1, as the red light host material.

[0117] (4) vacuum evaporating the electron transport layer TPBI and Alq3 on the light-emitting layer in sequence, with the evaporation rate of each being 0.1 nm / s and the evaporation film thickness being 10 nm and 15 nm respectively;

[0118] (5) 0.5 nm of LiF and 150 nm of Al were vacuum-deposited on the electron transport layer as the electron injection layer and cathode.

[0119] Device Application Example 2-16

[0120] Device Application Examples 2-16 respectively provide an organic electroluminescent device, which differs from Device Application Example 1 only in that the red light main material is different. The specific selection of the red light main material is shown in Table 2. The volume ratio of the two components in the red light main material evaporated onto the substrate is 1:1, and the other preparation steps and conditions are the same as those in Device Application Example 1.

[0121] Device Application Comparative Examples 1-5

[0122] Device application comparison examples 1-5 respectively provide an organic electroluminescent device, which is different from device application example 1 only in that the first host compound and / or the second host compound in the red light host material are different. The specific selection of the red light host material is shown in Table 2. The volume ratio of the two components in the red light host material evaporated onto the substrate is 1:1, and the other preparation steps and conditions are the same as those in device application example 1.

[0123] Performance Test:

[0124] The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used to test the brightness, driving voltage, current efficiency, and life test LT90 of the prepared organic electroluminescent device. Among them, the life test LT90 refers to the current density at room temperature (25-27°C) at the initial brightness (here 1000cd / m 2 ), the time required for the brightness to decrease to 90% of the initial brightness. In the following table, the driving voltage, current efficiency, and LT90 life are all relative values. The test results are detailed in Table 2 below.

[0125] Table 2

[0126]

[0127]

[0128] It can be seen from the contents of Table 2 that a composition having a specific composition is obtained by designing the specific composition of the composition and the structures of the first host compound and the second host compound. The composition is used as a material for the light-emitting layer of an organic electroluminescent device, and the prepared OLED device has a lower driving voltage, a higher current efficiency and a longer lifespan.

[0129] It can be seen from device application examples 1 and 4, and device application examples 3 and device application examples 6-7 that the second host compound containing a deuterated indolecarbazole group is preferably used to prepare the composition, which can further improve the life of the organic electroluminescent device.

[0130] It can be seen from device application examples 2 and 5 and 8 that the hydrogen atoms in the aromatic group on the indenocarbazole in the second main compound are replaced by deuterium atoms, and the prepared organic electroluminescent device has a longer lifespan. It can be seen from device application example 8 that the lifespan is better after only the methyl group on the indenocarbazole in the second main compound is replaced by deuterium.

[0131] It can be seen from device application examples 6 and 9 that the organic electroluminescent device prepared in the second main compound in which the hydrogen atom in the substituted phenyl group on the indolecarbazole ring is replaced by a deuterium atom has a longer life compared to the organic electroluminescent device prepared in the second main compound in which the hydrogen atom in the indolecarbazole ring is replaced by a deuterium atom.

[0132] By comparing device application examples 8, 12, 13 with device application examples 14, 15, 16, it can be seen that the use of a first host compound having a deuterated carbazole group in combination with a second host compound can further improve the life of the organic electroluminescent device.

[0133] By comparing device application example 8 with device application examples 12 and 13, it can be seen that the organic electroluminescent device prepared by using the first host compound having a para-biphenyl group and an ortho- (or meta-) biphenyl group in combination with the second host compound has a longer life.

[0134] Device Application Example 17

[0135] This device application example provides an organic electroluminescent device, and the composition provided by the present invention is selected as the red light main material in the organic electroluminescent device.

[0136] The structure of the organic electroluminescent device is: ITO / HT-1 (20nm) / electron blocking layer (5nm) / red light host material (35nm): Ir(piq)3[10%] / TPBI(10nm) / Alq3(15nm) / LiF(0.5nm) / Al(150nm). "Ir(piq)3[10%]" refers to the doping ratio of the red light dye, that is, the volume ratio of the red light host material to Ir(piq)3 is 90:10.

[0137] The organic electroluminescent device preparation process is as follows:

[0138] (1) a glass plate coated with an ITO transparent conductive layer was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in an acetone:ethanol mixed solvent, baked in a clean environment until the water was completely removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam;

[0139] (2) Place the glass substrate with the anode in a vacuum chamber and evacuate the chamber to a vacuum of 1×10 -5 ~9×10 -4 Pa, vacuum evaporating a hole transport layer HT-1 on the above anode layer film, the evaporation rate is 0.1nm / s, and the evaporation film thickness is 20nm;

[0140] (3) Vacuum evaporation of EB as an electron blocking layer on the hole transport layer at a rate of 0.1 nm / s and a film thickness of 5 nm;

[0141] (4) Vacuum-evaporating a red light host material and dye Ir(piq)3 on the electron blocking layer as the light-emitting layer of the organic electroluminescent device, with an evaporation rate of 0.1 nm / s and a total evaporation film thickness of 35 nm; In this embodiment, the first host compound H-1 and the second host compound E-1 are placed in different evaporation sources for heating, and the heating rate is controlled so that the volume ratio of the two evaporated onto the substrate is 1:1, as the red light host material.

[0142] (5) vacuum evaporating electron transport layers TPBI and Alq3 on the light-emitting layer in sequence, with the evaporation rate of each being 0.1 nm / s and the evaporation film thickness being 10 nm and 15 nm respectively;

[0143] (6) 0.5 nm of LiF and 150 nm of Al were vacuum evaporated on the electron transport layer as the electron injection layer and cathode.

[0144] Device Application Example 18

[0145] Device Application Example 18 provides an organic electroluminescent device, which differs from Device Application Example 17 only in that the electron blocking layer material is different (see Table 3 below for details), and the other preparation steps and conditions are the same as those of Device Application Example 17.

[0146] Performance Test:

[0147] The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used to test the brightness, driving voltage, current efficiency, and life test LT90 of the prepared organic electroluminescent device. Among them, the life test LT90 refers to the current density at room temperature (25-27°C) at the initial brightness (here 1000cd / m 2 ), the time required for the brightness to decrease to 90% of the initial brightness. In the following table, the driving voltage, current efficiency, and LT90 life are all relative values. The test results are detailed in Table 3 below.

[0148] Table 3

[0149]

[0150] It can be seen from the contents of Table 3 that in the present invention, by selecting a spirofluorene compound with a specific structure as the electron blocking layer material and combining it with a composition including a first main compound and a second main compound as the light-emitting layer material, the organic electroluminescent device prepared has higher current efficiency and longer service life.

[0151] The applicant declares that the present invention illustrates the detailed process flow of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed process flow, that is, it does not mean that the present invention must rely on the above-mentioned detailed process flow to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A composition of bicarbazole compounds containing a para-biphenyl substituent, characterized in that: The composition includes a first main compound and a second main compound, wherein the first main compound has a structure shown in the following formula I-1 or formula I-2, and the second main compound has a structure shown in the following formula II-1 or formula II-2: Wherein, X is selected from O, S, Any one of R 101 , R 102 Each independently selected from methyl or deuterated methyl, R 103 Selected from phenyl or deuterated phenyl, the dotted line indicates the attachment site.

2. The composition according to claim 1, characterized in that The second host is selected from any one of compounds E-1 to E-17:

3. The composition according to claim 1, characterized in that The second host is selected from the following compounds:

4. A compound, characterized in that The compound is: The compound is used to prepare the composition according to any one of claims 1 to 3.

5. An intermediate, characterized in that The intermediate is the following compound: The intermediate is used to prepare the second main compound in the composition as claimed in any one of claims 1 to 3.

6. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises an anode, a cathode and an organic thin film layer arranged between the anode and the cathode; The material of the organic thin film layer comprises the composition according to any one of claims 1 to 3.

7. The organic electroluminescent device according to claim 6, characterized in that: The organic thin film layer includes a light-emitting layer; The material of the light-emitting layer includes the composition according to any one of claims 1 to 3.

8. The organic electroluminescent device according to claim 6, characterized in that: The organic thin film layer includes a hole layer.

9. The organic electroluminescent device according to claim 8, characterized in that: The hole layer includes an electron blocking layer, and the material of the electron blocking layer includes a spirofluorene compound; The spirofluorene compound has a structure as shown in the following formula III: wherein X is selected from O or S; R 11 , R 21 Each is independently selected from hydrogen, deuterium, fluorine, CN, substituted or unsubstituted C1-C20 straight or branched alkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C6-C40 aryl; Ar is selected from substituted or unsubstituted C6-C40 arylene; Ar1 and Ar2 are each independently selected from substituted or unsubstituted C6-C40 aryl, substituted or unsubstituted C12-C40 oxygen heteroaryl, substituted or unsubstituted C12-C40 sulfur heteroaryl, and at least one of Ar1 or Ar2 is selected from any one of phenyl, naphthyl, triphenylene or fluoranthenyl; p is selected from 0 or 1; m and n are each independently selected from integers of 0-4.

10. A display device, characterized in that: The display device comprises the organic electroluminescent device according to any one of claims 6 to 9.

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