A deuterated composition, deuterated compound, intermediate, organic electroluminescent device and display device

Abstract

This invention provides a deuterated composition, a deuterated compound, an intermediate, an organic electroluminescent device, and a display device. The deuterated composition comprises at least two compounds, each having a structure as shown in Formula I; the organic electroluminescent device comprises an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode, the organic thin film layer being made of the aforementioned deuterated composition. The organic electroluminescent device provided by this invention exhibits a low driving voltage, high current efficiency, and a long lifespan.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials technology, specifically relating to a deuterated composition, a deuterated compound, an intermediate, an organic electroluminescent device, and a display device. Background Technology

[0002] Organic light-emitting diodes (OLEDs), as a novel display technology, possess unique advantages such as self-illumination, wide viewing angle, low energy consumption, high efficiency, thinness, rich colors, fast response speed, wide applicable temperature range, low driving voltage, the ability to manufacture flexible, bendable, and transparent display panels, and environmental friendliness. They can be applied to flat panel displays and next-generation lighting, and can also serve as backlights for LCDs. Compared with liquid crystal devices, they are brighter, have superior visibility, and can display information more clearly, thus attracting widespread attention.

[0003] Since the 1980s, organic light-emitting diodes (OLEDs) have been used in industry, such as in mobile phone displays. However, current OLED devices suffer from low efficiency and short lifespan, limiting their wider application, especially in large-screen displays. Developing more diverse and high-performance hole-based materials to meet the demands of high-performance OLED devices is a key research focus in this field.

[0004] In the field of display technology, triarylamine compounds are often used as hole-collecting materials to prepare organic electroluminescent devices (OLEDs). However, the performance of OLEDs prepared in this way still needs improvement, especially in terms of efficiency, lifetime, and voltage. Therefore, how to provide a hole-collecting material to improve the performance of OLEDs has become an urgent technical problem to be solved. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a deuterated composition, a deuterated compound, an intermediate, an organic electroluminescent device, and a display device. In this invention, by designing the compound structure and using a deuterated composition with a specific composition as the main material of the OLED light-emitting device, the OLED light-emitting device exhibits lower driving voltage, higher current efficiency, and longer lifespan.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a deuterated composition comprising at least two compounds, each having a structure as shown in Formula I;

[0008]

[0009] Among them, Ar 11 Ar 12 Ar21 Ar 22 Ar is independently selected from substituted or unsubstituted C6-C40 aryl groups and substituted or unsubstituted C12-C20 heteroaryl groups;

[0010] Ar 11 Ar 12 They can be connected via a single key, Ar 21 Ar 22 They can be connected via a single key; Ar, Ar 12 They can be connected via a single key, Ar, Ar 11 They can be connected via a single key, Ar, Ar 21 They can be connected via a single key, Ar, Ar 22 They can be connected via a single key;

[0011] n is selected from 0 or 1;

[0012] Ar 11 Ar 12 Ar 21 Ar 22 The substituents described in Ar are each independently selected from at least one of C1-C12 alkyl, C1-C12 alkoxy, and C6-C12 aryl groups;

[0013] The compound of formula I meets at least one of the following conditions:

[0014] (1) The compound of formula I does not contain deuterium atoms;

[0015] (2)Ar 11 Ar 12 Ar 21 Ar 22 Or, at least one of the hydrogen atoms in the substituents described in Ar is completely replaced by deuterium atoms;

[0016] (3)Ar 11 Ar 12 Ar 21 Ar 22 Or, at least one hydrogen atom in Ar is completely replaced by a deuterium atom;

[0017] The deuterated composition includes a compound of formula I that meets condition (2) or (3).

[0018] In this invention, by designing the structure of deuterated compounds and using a deuterated composition with a specific composition as the main material of OLED light-emitting devices, the OLED light-emitting devices have lower driving voltage, higher current efficiency, and longer lifespan.

[0019] In the field of display technology, triarylamine compounds are often used as hole layer materials for the fabrication of organic electroluminescent devices (OLEDs). However, the performance of these OLEDs still needs improvement, particularly in terms of efficiency, lifetime, and voltage. This invention utilizes at least two deuterated compounds with specific structural formulas as the hole layer material (including hole injection layer, hole transport layer, and electron blocking layer) for OLED light-emitting devices. This deuterated composition exhibits poor crystallinity and better film-forming properties, resulting in OLEDs with lower driving voltage, higher current efficiency, and longer lifetime.

[0020] In this invention, Ar 11 Ar 12 Ar 21 Ar 22 Ar is independently selected from substituted or unsubstituted C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) aryl groups, and substituted or unsubstituted C12-C20 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36, or C40, etc.) heteroaryl groups.

[0021] Ar 11 Ar 12 Ar 21 Ar 22 The substituents described in Ar are each independently selected from at least one of C1-C12 (e.g., C1, C2, C5, C6, C8, C10 or C12), C1-C12 (e.g., C1, C2, C5, C6, C8, C10 or C12), and C6-C12 (e.g., C6, C7, C8, C9, C10, C11 or C12) aryl groups.

[0022] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0023] As a preferred technical solution of the present invention, the Ar 11 Ar 12 Ar 21 Ar 22Ar is independently selected from any one of the following substituted or unsubstituted groups: phenyl, biphenyl, terphenyl, tetraphenyl, naphthyl, phenanthryl, anthracene, fluorenyl, benzo[a]fluorenyl, dibenzo[a]fluorenyl, triphenylene, fluoranyl, pyrene, perylene, spirofluorenyl, ind[a]fluorenyl, hydrogenated benzo[a]anthryl, dibenzofuran, dibenzo[a]thiophene, naphtho[a]benzofuran, naphtho[a]thiophene, dinaphtho[a]thiophene, dinaphtho[a]furan, dibenzo[a]furan, benzo[a]furan;

[0024] The substituents are each independently selected from at least one of the following: alkyl (e.g., C1, C2, C5, C6, C8, C10, or C12), alkoxy (e.g., C1, C2, C5, C6, C8, C10, or C12), and aryl (e.g., C6, C7, C8, C9, C10, C11, or C12).

[0025] It should be noted that if n is 0 in compound I, then Ar is a monosubstituted group of the above group; if n is 1, then Ar is a disubstituted group of the above group.

[0026] As a preferred technical solution of the present invention, the Ar 11 Ar 12 Ar 21 Ar 22 The substituents described in Ar are each independently selected from at least one of methyl, ethyl, tert-butyl, adamantyl, cyclohexyl, cyclopentyl, 1-methylcyclopentyl, 1-methylcyclohexyl, methoxy, phenyl, biphenyl, 9,9-dimethylfluorenyl, dibenzofuranyl, dibenzothiophene, or naphthyl.

[0027] As a preferred embodiment of the present invention, the Ar is selected from any one of the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, phenanthryl, anthracene, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirofluorenyl, dibenzofuranyl, dibenzothiopheneyl, triphenylene, fluorenyl, benzofluorenyl;

[0028] The substituent is selected from at least one of methyl, ethyl, tert-butyl, adamantyl, cyclohexyl, cyclopentyl, 1-methylcyclopentyl, 1-methylcyclohexyl, methoxy, phenyl, biphenyl, 9,9-dimethylfluorenyl, dibenzofuranyl, dibenzothiophene, or naphthyl.

[0029] In this invention, the Ar is selected from any one of the following substituted or unsubstituted groups:

[0030]

[0031]

[0032] The substitution refers to the partial replacement of hydrogen atoms in the aforementioned groups by deuterium atoms, or the complete replacement of all hydrogen atoms in the aforementioned groups by deuterium atoms. Since some of the aforementioned groups contain substituents, the partial replacement of hydrogen atoms by deuterium atoms means that only the hydrogen atoms on the substituents are completely replaced by deuterium atoms. For example, if Ar is... If Ar is selected from 9,9-diphenylfluorenyl substituted with adamantyl, then the hydrogen atoms in this group are partially replaced by deuterium atoms, meaning that all the hydrogen atoms on the adamantyl group are replaced by deuterium atoms, while the hydrogen atoms on the 9,9-diphenylfluorenyl group are not replaced by deuterium atoms.

[0033] Preferably, the Ar 11 Ar 12 Ar 21 Ar 22 Each group is independently selected from any one of the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, triphenylene, fluoranyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, spirofluorenyl, dibenzofuranyl, dibenzothiopheneyl;

[0034] Each of the substituents is independently selected from at least one of methyl, ethyl, tert-butyl, adamantyl, cyclohexyl, cyclopentyl, 1-methylcyclopentyl, 1-methylcyclohexyl, methoxy, phenyl, biphenyl 9,9-dimethylfluorenyl, dibenzofuranyl, dibenzothiophene, or naphthyl.

[0035] In this invention, the Ar 11 Ar 12 Ar 21 Ar 22 Each group is independently selected from any one of the following substituted or unsubstituted groups:

[0036]

[0037]

[0038] The substitution refers to the partial replacement of hydrogen atoms in the aforementioned groups by deuterium atoms, or the complete replacement of all hydrogen atoms in the aforementioned groups by deuterium atoms. Since some of the aforementioned groups contain substituents, the partial replacement of hydrogen atoms by deuterium atoms means that all hydrogen atoms on the substituent are replaced by deuterium atoms. For example, if Ar... 11 for Representing Ar 11 If the diphenyl group is selected from methyl-substituted diphenyl, then the hydrogen atoms in the group are partially replaced by hydrogen atoms, meaning that all the hydrogen atoms on the methyl group are replaced by deuterium atoms, while the hydrogen atoms on the diphenyl group are not replaced by deuterium atoms.

[0039] As a preferred embodiment of the present invention, the compound of Formula I is selected from any one of the following substituted or unsubstituted compounds:

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054] The substitution refers to the replacement of some or all of the hydrogen atoms in the above-mentioned compound with deuterium atoms.

[0055] In this invention, the substitution refers to the partial or complete replacement of hydrogen atoms in the above-mentioned compounds by deuterium atoms. Specifically, the partial replacement of hydrogen atoms by deuterium atoms means that in the compound of formula I, the corresponding Ar atoms are replaced by deuterium atoms. 11 Ar 12 Ar 21 Ar 22 Or, at least one of the substituents at the Ar position has its hydrogen atoms completely replaced by deuterium atoms, or Ar 11 Ar 12 Ar 21 Ar 22 Alternatively, at least one hydrogen atom in Ar is completely replaced by a deuterium atom, and at least one hydrogen atom is not replaced by a deuterium atom. For example, compound I is... Then it can be seen that when n is 0, Ar 11 It is a phenyl group, Ar 12Ar is a diphenyl group, and Ar is a tert-butyl-substituted spirofluorenyl group. In this Formula I compound, the hydrogen atom part is replaced by a deuterium atom, which means that the hydrogen atom on the tert-butyl group is replaced by a deuterium atom, while the other hydrogen atoms are not replaced. This can be referred to as the hydrogen atom part being replaced by a deuterium atom in Formula I compound; or all the hydrogen atoms in any one or any combination of two of the tert-butyl-substituted spirofluorenyl group, phenyl group, and diphenyl group are replaced by deuterium atoms. This can also be referred to as the hydrogen atom part being replaced by a deuterium atom in Formula I compound.

[0056] Preferably, the compound of formula I is selected from any one of the following compounds:

[0057]

[0058]

[0059] As a preferred embodiment of the present invention, the deuteration rate of the deuterated composition is 1 to 70% (for example, it can be 1%, 3%, 5%, 10%, 20%, 25%, 30%, 40%, 50%, 60% or 70%, etc.), preferably 1 to 25%.

[0060] It should be noted that the deuteration rate refers to the percentage of deuterium atoms (D) in the composition or compound relative to the total number of deuterium atoms and hydrogen atoms (H), i.e., deuteration rate = y / (x+y)*100%, where y is the number of deuterium atoms in the composition or compound and x is the number of hydrogen atoms in the composition or compound. If the composition or compound consists entirely of H atoms and has no D atoms, the deuteration rate is 0%. If all H atoms in the composition or compound are replaced by D atoms, the deuteration rate is 100%.

[0061] Secondly, the present invention provides a deuterated compound, wherein the deuterated compound is selected from any one of the following deuterated compounds:

[0062]

[0063] The deuterated compound is used to prepare the deuterated composition as described in the first aspect.

[0064] Thirdly, the present invention provides an intermediate, the intermediate being...

[0065] The intermediate is used to prepare the deuterated compound as described in the second aspect.

[0066] Fourthly, 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;

[0067] The material of the organic thin film layer includes the deuterated composition as described in the first aspect.

[0068] Preferably, the organic thin film layer includes a hole layer;

[0069] The hole layer includes a hole injection layer, a hole transport layer, and an electron blocking layer;

[0070] The material of the cavity layer includes the deuterated composition as described in the first aspect.

[0071] Fifthly, the present invention provides a display device comprising the organic electroluminescent device as described in the fourth aspect.

[0072] Compared with the prior art, the present invention has the following beneficial effects:

[0073] In this invention, by designing the composition of the deuterated composition and further by using a combination of deuterated compounds with specific structural formulas, and by using this deuterated composition as the material for the hole layer of the OLED light-emitting device, the OLED light-emitting device has a lower driving voltage, higher current efficiency, and longer lifespan. Detailed Implementation

[0074] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0075] The organic electroluminescent devices provided in the following examples and comparative examples contain any one or a combination of at least two of the following compounds:

[0076]

[0077]

[0078] The preparation methods for some of the above compounds are as follows:

[0079] (I) Synthesis of D8-HTSP2:

[0080]

[0081] Under nitrogen protection, 200 mL of dry toluene, 5.0 g (0.0095 mol) of the compound shown in MA, 2.4 g (0.0099 mol) of 2-bromodeuterated biphenyl, 0.0575 g (0.0001 mol) of Pd(dba)2 (bis(dibenzylacetone palladium)), 0.4 g (0.0002 mol) of a toluene solution containing 10% by mass of tri-tert-butylphosphine, and 1.44 g (0.015 mol) of sodium tert-butoxide were added to a 500 mL three-necked flask. The mixture was heated to reflux and reacted for 12 h. After cooling to room temperature, water was added to dissolve the mixture. The organic layer was then washed with water until neutral, dried with magnesium sulfate, filtered to remove magnesium sulfate, concentrated to dryness, and separated by silica gel column chromatography. The solution was eluted with petroleum ether to give 5.1 g of compound D8-HTSP2.

[0082] Mass spectrometry analysis of compound D8-HTSP2 revealed a mass-to-charge ratio (m / z) of 684.35.

[0083] (II) Synthesis of D8-HTSP3:

[0084]

[0085] Following the synthetic method of D8-HTSP2, replace the compound shown in MA with an equal amount of... D8-HTSP3 was obtained.

[0086] Mass spectrometry analysis of compound D8-HTSP3 revealed a mass-to-charge ratio (m / z) of 684.35.

[0087] (III) Synthesis of D8-HTSP4:

[0088] (1) Synthesis of intermediate M-1

[0089]

[0090] Under nitrogen protection, 200 mL of dry toluene, 10 g (0.048 mol) of 2-amino-9,9-dimethylfluorene, 11.6 g (0.048 mol) of 2-bromodeuterated biphenyl, 0.1725 g (0.0003 mol) of Pd(dba)2 (bis(dibenzylacetone palladium), 1.2 g (0.0006 mol) of a toluene solution containing 10% by weight of tri-tert-butylphosphine, and 5.76 g (0.06 mol) of sodium tert-butoxide were added to a 500 mL three-necked flask. The mixture was heated to reflux and reacted for 12 h. After cooling to room temperature, water was added to liquefy the mixture. The organic layer was then washed with water until neutral, dried with magnesium sulfate, filtered to remove magnesium sulfate, concentrated to dryness, and separated by silica gel column chromatography. The elution was performed with petroleum ether:ethyl acetate = 20:1 (v / v) to give 6.9 g of intermediate M-1.

[0091] Mass spectrometry analysis of intermediate M-1 revealed a mass-to-charge ratio (m / z) of 370.24, confirming the product's molecular formula as C1. 27 H 14 D9N.

[0092] (2) Synthesis of D8-HTSP4:

[0093]

[0094] Following the synthetic method of D8-HTSP2, the compound shown in MA was replaced with an equimolar amount of the compound shown in M-1, and the 2-bromodeuterated biphenyl was replaced with an equimolar amount of... D8-HTSP4 was obtained.

[0095] Mass spectrometry analysis of compound D8-HTSP4 revealed a mass-to-charge ratio (m / z) of 796.47.

[0096] (IV) Synthesis of D8-HTCZ1:

[0097]

[0098] Following the synthetic method of D8-HTSP2, replace the compound shown in MA with an equimolar amount. Replacing 2-bromodeuterated biphenyl with an equal amount of 4-bromodeuterated biphenyl yields 8-HTCZ1.

[0099] Mass spectrometry analysis of compound D8-HTCZ1 yielded a mass-to-charge ratio (m / z) of 687.36.

[0100] Synthesis of (V)D18-HTCZ2:

[0101]

[0102] Following the synthetic method of D8-HTSP2, replace the compound shown in MA with an equimolar amount. 2-bromodeuterium biphenyl is replaced with 4-bromodeuterium biphenyl, and the amount of 4-bromodeuterium biphenyl is... The amount of sodium tert-butoxide is twice the amount of its original substance. The amount of substance was 2.2 times that of the substance, and the reaction time was 36 hours to obtain D18-HTCZ2.

[0103] Mass spectrometry analysis of compound D18-HTCZ2 revealed a mass-to-charge ratio (m / z) of 654.37.

[0104] Other compounds of formula I can be prepared by referring to the above methods, and will not be described in detail in this invention.

[0105] The deuteration rates of the deuterated compositions provided in the following examples are shown in Table 1 below. The deuteration rate is obtained by calculation. The deuteration rate refers to the percentage of the number of deuterium atoms (D) in the composition or compound relative to the total number of deuterium atoms and hydrogen atoms (H), i.e., deuteration rate = y / (x+y)*100%, where y is the number of deuterium atoms in the composition or compound and x is the number of hydrogen atoms in the composition or compound. Assuming that the composition or compound is entirely composed of H and has no D, the deuteration rate is 0%. If all H atoms in the composition or compound are replaced by D, the deuteration rate is 100%.

[0106] Table 1

[0107] Product Name Number of hydrogen atoms in a single molecule Number of deuterium atoms in a single molecule Deuteration rate HTSP1 33 0 0 D4-HTSP1 28 5 15.2％ D8-HTSP1 23 10 30.3％ HTSP2 37 0 0 D8-HTSP2 28 9 24.3％ HTSP3 37 0 0 D8-HTSP3 28 9 24.3％ HTSP4 53 0 0 D8-HTSP4 44 9 17.0％ HTC Z1 38 0 0 D8-HTCZ1 29 9 23.7 HTC Z2 32 0 0 D18-HTCZ2 14 18 56.3％

[0108] The specific structures of the other compounds used in the following examples are shown below:

[0109]

[0110] Application Example 1

[0111] This application example provides an organic electroluminescent device with the following structure: ITO / HTL:HI-2(5%) (20nm) / HTL(50nm) / HTSP3(20nm) / BH266(30nm) / ETL-1(30nm) / EIL-1(1nm) / Al(150nm);

[0112] The specific preparation process is as follows: each layer of material is placed in a vacuum chamber, and the vacuum is evacuated to 1×10⁻⁶. -5 ~1×10 -6 Pa is sequentially vacuum-deposited onto the cleaned ITO substrate. Here, HTL:HI-2(5%) (20nm) refers to the fact that in this device, HTL and HI-2 are co-evaporated at a volume ratio of 95:5 to form a hole injection layer with a thickness of 20nm.

[0113] In this application example, the HTL material is a mixture of D4-HTSP1 and D8-HTSP1. By placing these two different compounds in different evaporation sources and controlling the evaporation rate of the two compounds by controlling the temperature of the evaporation sources, a mixture with the desired volume ratio is obtained and used as the HTL for the device.

[0114] In the device provided in this application example, HTL:HI-2 (5%) (20nm) is the hole injection layer, HTL (50nm) is the hole transport layer, and HTSP3 (20nm) is the electron blocking layer. In this application example, a mixture of D4-HTSP1 and D8-HTSP1 is used as both the hole injection material and the hole transport material in this device, and their volume ratio is 5:5.

[0115] Application Example 2-6

[0116] The only difference between Application Examples 2-6 and Application Example 1 is that the HTL material is different (the specific composition and volume are as described in Table 2 below), while the other preparation steps are the same as in Application Example 1.

[0117] Comparative Application Examples 1-3

[0118] The only difference between Application Examples 1-3 and Application Example 1 is that the HTL material is a single compound (the specific composition and volume are as described in Table 2 below), while the other preparation steps are the same as in Application Example 1.

[0119] Performance testing

[0120] Test Method: The OLED-1000 multi-channel accelerated aging lifetime and photoluminescence performance analysis system manufactured by Hangzhou Yuanfang was used for testing. The test items included the brightness, driving voltage, current efficiency, and LT80 of the organic electroluminescent device; where LT80 refers to maintaining the device's initial brightness of 1000 cd / m². 2 With the current density remaining constant, the device efficiency drops to the initial luminance of 1000 cd / m². 2 The time required to achieve 80% of the corresponding efficiency.

[0121] The specific test results are shown in Table 2 below:

[0122] It should be noted that, since the materials have roughly the same density and the molecular weights of the materials are not significantly different, the volume ratio is directly converted into the mole ratio when calculating the deuteration rate. This deuteration rate is just a calculated value and not the deuteration rate in the strict sense.

[0123] Table 2

[0124]

[0125] As shown in Table 2, by designing the deuterated compounds in the deuterated composition and controlling the deuteration rate of the deuterated composition within a specific range, the organic electroluminescent device prepared by using it as a material for the hole layer has a lower driving voltage, higher current efficiency, and longer lifespan.

[0126] As can be seen from the data in Application Examples 5-6, the deuteration rate is low, and good results can be achieved with fewer deuterated compounds D4-HTSP1 and D8-HTSP1, resulting in lower costs.

[0127] Meanwhile, based on the data from comparative application examples 1-3, it can be seen that if a single compound is selected as the material for the hole layer, the prepared organic electroluminescent device has a low current efficiency and a short lifespan.

[0128] Application Example 7-10

[0129] The only difference between Application Examples 7-10 and Application Example 1 is that the HTL material is different (the specific composition and volume are as described in Table 3 below), while the other preparation steps are the same as in Application Example 1.

[0130] Compare and contrast with example 4-7

[0131] The only difference between Application Examples 4-7 and Application Example 1 is that the HTL material is a single compound (the specific composition and volume are as described in Table 3 below), while the other preparation steps are the same as in Application Example 1.

[0132] Performance testing

[0133] Test Method: The OLED-1000 multi-channel accelerated aging lifetime and photoluminescence performance analysis system manufactured by Hangzhou Yuanfang was used for testing. The test items included the brightness, driving voltage, current efficiency, and LT80 of the organic electroluminescent device; where LT80 refers to maintaining the device's initial brightness of 1000 cd / m². 2 With the current density remaining constant, the device efficiency drops to the initial luminance of 1000 cd / m². 2 The time required to achieve 80% of the corresponding efficiency.

[0134] The specific test results are shown in Table 3 below:

[0135] It should be noted that, since the materials have roughly the same density and the molecular weights of the materials are not significantly different, the volume ratio is directly converted into the mole ratio when calculating the deuteration rate. This deuteration rate is just a calculated value and not the deuteration rate in the strict sense.

[0136] Table 3

[0137]

[0138] As shown in Table 3, by designing the deuterated compounds in the deuterated composition and controlling the deuteration rate of the deuterated composition within a specific range, the organic electroluminescent device prepared by using it as a material for the hole layer has a lower driving voltage, higher current efficiency, and longer lifespan.

[0139] As can be seen from the data in Application Examples 9-10, the organic electroluminescent devices prepared by using the deuterated compound D8-HTSP1 in this invention have better performance and lower cost when the deuteration rate of the deuterated composition composed of it is relatively low.

[0140] Meanwhile, based on the data from comparative application examples 4-7, it can be seen that if a single compound is selected as the material for the hole layer, the prepared organic electroluminescent device has a lower current efficiency and a shorter lifespan.

[0141] Application Examples 11-12

[0142] The only difference between Application Examples 11-12 and Application Example 1 is that the HTL material is different (the specific composition and volume are as described in Table 4 below), while the other preparation steps are the same as in Application Example 1.

[0143] Compare and contrast with example 8-11

[0144] The only difference between Application Examples 8-11 and Application Example 1 is that the HTL material is a single compound (the specific composition and volume are as described in Table 4 below), while the other preparation steps are the same as in Application Example 1.

[0145] Performance testing

[0146] Test Method: The OLED-1000 multi-channel accelerated aging lifetime and photoluminescence performance analysis system manufactured by Hangzhou Yuanfang was used for testing. The test items included the brightness, driving voltage, current efficiency, and LT80 of the organic electroluminescent device; where LT80 refers to maintaining the device's initial brightness of 1000 cd / m². 2 With the current density remaining constant, the device efficiency drops to the initial luminance of 1000 cd / m². 2 The time required to achieve 80% of the corresponding efficiency.

[0147] The specific test results are shown in Table 4 below:

[0148] It should be noted that, since the materials have roughly the same density and the molecular weights of the materials are not significantly different, the volume ratio is directly converted into the mole ratio when calculating the deuteration rate. This deuteration rate is just a calculated value and not the deuteration rate in the strict sense.

[0149] Table 4

[0150]

[0151] As shown in Table 4, by designing the deuterated compounds in the deuterated composition and controlling the deuteration rate of the deuterated composition within a specific range, the organic electroluminescent device prepared by using it as a material for the hole layer has a lower driving voltage, higher current efficiency, and longer lifespan.

[0152] As can be seen from the data in Application Example 11, the organic electroluminescent device prepared by using the deuterated compound D8-HTSP1 in this invention has a better effect and lower cost when the deuteration rate of the deuterated composition composed of it is relatively low.

[0153] Meanwhile, based on the data from comparative application examples 8-11, it can be seen that if a single compound is selected as the material for the hole layer, the prepared organic electroluminescent device has a lower current efficiency and a shorter lifespan.

[0154] In summary, by designing the deuterated compounds in the deuterated composition and controlling the deuteration rate of the deuterated composition within a specific range, this invention utilizes the deuterated compounds as materials for the hole layer to prepare organic electroluminescent devices with low driving voltage, high current efficiency, and long lifespan.

[0155] The applicant declares that the detailed process flow of this invention is illustrated by the above embodiments, but this invention is not limited to the above detailed process flow, that is, it does not mean that this invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A deuterated composition, characterized in that, The deuterated composition comprises at least two compounds, each having a structure as shown in Formula I; Where n is selected from 0; Ar is selected from substituted or unsubstituted spirofluorene groups, wherein the substituent in Ar is selected from any one of methyl, ethyl, or tert-butyl. 21 Ar 22 Each group is independently selected from any one of the following groups, substituted or unsubstituted: phenyl, biphenyl, naphthyl, or 9,9-dimethylfluorenyl, Ar 21 Ar 22 The substituents mentioned herein are selected from phenyl groups; The compound of formula I meets at least one of the following conditions: (1) The compound of formula I does not contain deuterium atoms; (2)Ar 21 Or Ar 22 In the case described above, at least one hydrogen atom in the substituents is completely replaced by a deuterium atom; (3)Ar 21 Ar 22 Or, at least one hydrogen atom in Ar is completely replaced by a deuterium atom; The deuterated composition includes a compound of formula I that meets condition (2) or (3).

2. The deuterated composition according to claim 1, characterized in that, The compound of formula I is selected from any one of the following substituted or unsubstituted compounds: The substitution refers to the partial or complete replacement of hydrogen atoms in the above-mentioned compound by deuterium atoms.

3. The deuterated composition according to claim 1, characterized in that, The deuteration rate of the deuterated composition is 1-70%.

4. The deuterated composition according to claim 3, characterized in that, The deuteration rate of the deuterated composition is 1-25%.

5. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode; The material of the organic thin film layer includes the deuterated composition as described in any one of claims 1-4.

6. The organic electroluminescent device according to claim 5, characterized in that, The organic thin film layer includes a hole layer; The hole layer includes a hole injection layer, a hole transport layer, and an electron blocking layer; The material of the cavity layer includes the deuterated composition as described in any one of claims 1-4.

7. A display device, characterized in that, The display device includes the organic electroluminescent device as described in claim 5 or 6.

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