Organic light-emitting material and organic electroluminescent device, display device, and lighting device comprising the same

Abstract

The application belongs to the technical field of OLED, and specifically comprises an organic light-emitting material, an organic electroluminescent device comprising the same, a display device, and an illuminating device. The structural general formula of the organic light-emitting material is shown below. By introducing a deuterated oxygen heteroaromatic ring through a specific site on R1 or R2, the application can promote the formation of intermolecular hydrogen bonds, significantly improve the horizontal molecular orientation after film formation, and enable the prepared device to maintain a lower driving voltage and higher efficiency after experiencing high-temperature long-time use, without causing a significant broadening of the emission half-peak width and unpredictable red shift of the emission spectrum. Furthermore, it is found that when the compounds provided by the application are used in combination, especially when the oxygen heteroaryl groups use the same structure, the conjugation and induction effect caused by the oxygen atoms are basically consistent, the orientation induction effect is more obvious, the molecular orientation of the combination is higher, and the high-temperature stability of the device is further improved.I.

Description

Technical Field

[0001] This invention belongs to the field of OLED technology, specifically including an organic light-emitting material and an organic electroluminescent device, display device and lighting device containing the same. Background Technology

[0002] In OLED devices, the molecular orientation of the emitting layer film is one of the core factors determining the device's photoelectric performance and operational stability. A well-ordered molecular orientation can significantly optimize the film's microstructure: on the one hand, it enables the regular stacking of emitting material molecules, effectively improving carrier migration efficiency, reducing device operating voltage drop, and improving photoelectric conversion efficiency; on the other hand, it optimizes the energy transfer path between the host and guest materials in the emitting layer, improving host-guest energy transfer efficiency, reducing non-radiative transition losses, and significantly extending the lifespan of OLED devices. Therefore, controlling the molecular orientation of emitting materials and improving the regularity of film arrangement has become a key research direction for high-performance OLED materials.

[0003] Currently, there are many methods to improve the molecular orientation of materials, such as increasing the planarity of the molecular structure and using large conjugated fused ring structures to enhance intermolecular stacking. However, all of these methods increase the molecular weight of the material, leading to problems such as reduced thermal stability of the compound. Recently, the applicant discovered in their research that by increasing the strength of intermolecular hydrogen bonds, the intermolecular interactions of the material can be increased, thereby forming a more regular thin film and improving molecular orientation.

[0004] Oxaaryl groups are common substituents in current OLED blue light host materials. The lone pair electrons on the oxygen atom can form intramolecular or intermolecular hydrogen bonds with hydrogen atoms. By substituting the hydrogen atoms adjacent to the oxygen atom, intramolecular hydrogen bonds can be prevented, thereby improving molecular orientation.

[0005] For dibenzofuran-like structures, the inductive effect of the oxygen atom significantly increases the acidity of the hydrogen atoms on the two carbons adjacent to the oxygen atom, allowing them to form intramolecular hydrogen bonds with the lone pair electrons of the oxygen atom. These relatively stable hydrogen bonds reduce intermolecular interactions. When these hydrogen atoms are replaced with deuterium or other deuterated substituents, the increased number of deuterium neutrons shortens the bond length, weakens the acidity, and makes it difficult to form intramolecular hydrogen bonds. This, in turn, promotes the formation of intermolecular hydrogen bonds between the lone pair electrons of the oxygen atom and other molecules.

[0006] Furthermore, most current mainstream blue light source materials contain anthracene-based framework structures. Anthracene-based materials possess excellent blue light luminous efficiency and carrier transport characteristics, making them the core material system for commercial blue OLEDs. However, anthracene-based materials suffer from significant high-temperature stability defects. During long-term high-temperature operation and mass production, the aryl groups on the anthracene structure are prone to intramolecular or intermolecular dehydrogenation condensation side reactions, generating ultra-large conjugated structural impurities. These conjugated impurities can cause severe device performance degradation, not only leading to exciton quenching and reduced luminous efficiency, but also causing irregular redshift and broadening of the spectral half-peak in the device's emission spectrum, significantly reducing display color purity and image consistency, making it difficult to meet the high-temperature and harsh operating conditions required for automotive applications. Summary of the Invention In view of the above-mentioned problems existing in the prior art, the present invention provides an organic light-emitting material and an organic electroluminescent device, display device and lighting device containing the same.

[0007] To achieve the above objectives, the technical solution adopted by the present invention includes: A first aspect of the present invention provides an organic light-emitting material, the general structural formula of which is shown below: I; R1 is selected from any one of phenyl, naphthyl, phenanthryl, pyrene, triphenylene, and biphenyl; R2 is selected from an oxaaryl group, wherein the oxaaryl group is selected from one of the structures shown in formulas a1 to a27 below: a1、 a2、 a3、 a4、 a5、 a6、 a7、 a8、 a9、 a10、 a11、 a12、 a13、 a14、 a15、 a16、 a17、 a18、 a19、 a20、 a21、 a22、 a23、 a24、 a25、 a26、 a27; Ar 21 To Ar 29 Each is independently selected from hydrogen or phenyl; In Formula I, any hydrogen atom other than the groups a1 to a27 can be substituted with deuterium.

[0008] Furthermore, R2 is selected from one of the following structures: , , , , , , , , .

[0009] Furthermore, R2 is selected from one of the following structures: , , , , , , , , , , .

[0010] Furthermore, R1 is selected from... , , , , , , , , , , , , Any one of them.

[0011] Furthermore, the organic light-emitting material is selected from the structure shown below: .

[0012] A second aspect of the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising an anode, a hole transport region, a light-emitting layer, an electron transport region and a cathode sequentially disposed on a substrate; wherein the light-emitting layer comprises one or more organic light-emitting materials as described above.

[0013] Furthermore, the light-emitting layer includes a host material and a guest material, wherein the host material includes one or more organic light-emitting materials as described above.

[0014] Furthermore, the host material includes at least two organic light-emitting materials as described above, wherein the two organic light-emitting materials are selected from the following formulas I-1 and I-2, respectively: I-1 I-2; R 1-1 R 1-2Whether the components are the same or different, they are each independently selected from any one of phenyl, naphthyl, phenanthrene, pyrene, triphenylene, and biphenyl. R 2-1 R 2-2 Oxaaryl groups representing the same or different general structural formulas are each independently selected from one of formulas a1-a8; or R 2-1 R 2-2 Selected from formula a9 or formula a10; or R 2-1 R 2-2 Selected from formula a11 or formula a12; or R 2-1 R 2-2 Selected from formula a13 or formula a14; or R 2-1 R 2-2 Selected from formula a15 or formula a16; or R 2-1 R 2-2 Selected from formula a17 or formula a18; or R 2-1 R 2-2 Selected from formula a19 or formula a20; or R 2-1 R 2-2 Selected from formula a21 or formula a22; or R 2-1 R 2-2 Selected from formula a23 or formula a24; or R 2-1 R 2-2 Selected from formula a25 or formula a26; or R 2-1 R 2-2 Selected from formula a27.

[0015] Furthermore, the R 1-1 R 1-2 Whether the two are the same or different, each is selected independently. , , , , , , , , , , , , Any one of them.

[0016] Furthermore, the main material includes at least one of the following combinations: Combination 1: ; Combination 2: ; Combination 3: ; Combination 4: ; Combination 5: ; Combination 6: ; Combination 7: ; Combination 8: ; Combination 9: ; Combination 10: ; Combination 11: ; Combination 12: ; Combination 13: ; Combination 14: ; Combination 15: ; Combination 16: ; Combination 17: ; Combination 18: ; Combination 19: ; Combination 20: ; Combination 21: ; Combination 22: ; Combination 23: ; Combination 24: ; Combination 25: .

[0017] Combination 26:

[0018] Combination 27:

[0019] Combination 28:

[0020] Combination 29: .

[0021] Furthermore, the mass ratio of the two compounds in combinations 1 to 29 is 2:8 to 8:2, preferably 4:6 to 6:4, and more preferably 5:5.

[0022] For example, in combination 1, the mass ratio of compound C1 to compound C2 is 2:8 to 8:2, preferably 4:6 to 6:4, and more preferably 5:5.

[0023] For example, in combination 2, the mass ratio of compound C2 to compound C3 is 2:8 to 8:2, preferably 4:6 to 6:4, and more preferably 5:5.

[0024] For example, in combination 3, the mass ratio of compound C5 to compound C7 is 2:8 to 8:2, preferably 4:6 to 6:4, and more preferably 5:5.

[0025] For example, in combination 4, the mass ratio of compound C6 to compound C10 is 2:8 to 8:2, preferably 4:6 to 6:4, and more preferably 5:5.

[0026] For example, in combination 5, the mass ratio of compound C4 to compound C12 is 2:8 to 8:2, preferably 4:6 to 6:4, and more preferably 5:5.

[0027] For example, in combination 6, the mass ratio of compound C9 to compound C13 is 2:8 to 8:2, preferably 4:6 to 6:4, and more preferably 5:5.

[0028] For example, in combination 7, the mass ratio of compound C11 to compound C14 is 2:8 to 8:2, preferably 4:6 to 6:4, and more preferably 5:5.

[0029] A third aspect of the present invention provides a display device comprising the organic electroluminescent device as described above.

[0030] A fourth aspect of the present invention provides a lighting device comprising an organic electroluminescent device as described above.

[0031] Beneficial effects of this invention: This invention promotes the formation of intermolecular hydrogen bonds by introducing deuterated oxaaromatic rings at specific sites on R1 or R2, which significantly improves the horizontal molecular orientation of the material after film formation. This allows the prepared device to maintain a low driving voltage and high efficiency even after long-term use at high temperatures, without causing significant broadening of the emission half-width or unpredictable redshift of the emission spectrum.

[0032] Furthermore, it has been found that when the compounds provided by this invention are used in combination, especially when the oxaaryl groups use the same structure, the conjugation and induction effects caused by oxygen atoms are basically the same, and the orientation induction effect is more obvious, resulting in a higher molecular orientation of the composition, thereby further improving the high-temperature stability of the device. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of the organic electroluminescent device of the present invention, wherein 1-substrate, 2-anode, 3-hole injection layer, 4-hole transport layer, 5-light-emitting auxiliary layer, 6-light-emitting layer, 7-hole blocking layer, 8-electron transport layer, 9-electron injection layer, 10-cathode, and 11-capping layer. Detailed Implementation

[0034] To better understand the content of this invention, it will be described in detail with reference to the accompanying drawings and embodiments.

[0035] The compounds of this invention are applicable to light-emitting elements, display panels, and electronic devices, particularly organic electroluminescent devices. The electronic devices described in this invention are devices comprising a layer of at least one organic compound, and may also comprise layers of inorganic materials or layers formed entirely of inorganic materials. Preferably, the electronic devices are organic electroluminescent devices (OLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic dye-sensitized solar cells (O-DSSCs), organic optical detectors, organic photosensors, organic field quenching devices (O-FQDs), light-emitting electrochemical cells (LECs), organic laser diodes (O-lasers), and organic plasma emitting devices. Organic electroluminescent devices (OLEDs) are particularly preferred. A schematic diagram of an exemplary organic electroluminescent device is shown below. Figure 1 As shown.

[0036] Experimental Section To better understand the content of this invention, the polycyclic compound, the preparation method of the compound, and the luminescent properties of the device will be explained in detail with reference to embodiments. Various chemical reactions can be applied to the synthesis method of the compound according to one embodiment of this invention. However, it should be noted that the synthesis method of the compound according to one embodiment of this invention is not limited to the synthesis method described below. Unless otherwise stated, subsequent synthesis is carried out in an anhydrous solvent under a protective gas atmosphere. Solvents and reagents can be purchased from conventional reagent suppliers.

[0037] intermediate synthesis

[0038] Compound Sub-1 (60.5 g, 200 mmol) was added to 500 mL of tetrahydrofuran and stirred at room temperature until dissolved. The reaction mixture was then cooled to -78 °C under nitrogen protection. 410 mL of a sec-butyllithium tetrahydrofuran solution (1N) was slowly added dropwise to the reaction mixture. After the addition was complete, the reaction mixture was brought back to room temperature and stirred for 1 hour. Then, deuterated methanol (13.5 g, 410 mmol) was added to the reaction mixture, and stirring continued for 30 minutes. The reaction mixture was then added to a mixture of 500 mL toluene and 500 mL water. The mixture was separated, the organic phase was dried, and excess solvent was removed under vacuum. The crude product was purified by column chromatography (n-hexane:dichloromethane = 5:1, v / v) to give product Sub-2 (53.0 g, 174 mmol), yield: 87%, MS (m / z) (M+): 305.

[0039] Compound Sub-2 (53.0 g, 174 mmol), bis(pinacol)diboron (48.3 g, 183 mmol), and potassium acetate (34.1 g, 348 mmol) were added to 1000 mL of DMF. After thorough stirring, dppf palladium dichloride (3.6 g, 5 mmol) was added under nitrogen protection, and the reaction system was heated to 100 °C. After 6 hours, the reaction system was added to a mixture of 2000 mL toluene and 2000 mL water. The mixture was separated, the organic phase was dried, and excess solvent was removed under vacuum. The crude product was purified by column chromatography (n-hexane:dichloromethane = 3:1) to give product A11 (47.6 g, 120 mmol), yield: 69%, MS (m / z) (M+): 397.

[0040] Other intermediate compounds AX can be prepared by referring to the preparation method of intermediate compound A11 above, simply by replacing compound Sub-2 with the corresponding reaction substrate. The results are shown in Table 1 below.

[0041] Table 1

[0042] Synthesis Example 1

[0043] In a 250 mL three-necked flask under nitrogen protection, 50 mL of toluene, 25 mL of ethanol, and 25 mL of water were added. Then, compounds A1 (7.4 g, 20 mmol), B1 (6.8 g, 20 mmol), potassium carbonate (4.15 g, 30 mmol), and tetraphenylphosphine palladium (0.35 g, 0.3 mmol) were added. The mixture was heated to reflux for 4 h. After the reaction was complete, the mixture was cooled to room temperature, and the aqueous and organic phases were separated. The organic phase was purified by rotary evaporation to remove the solvent, followed by column chromatography (n-hexane:dichloromethane = 3:1, v / v) to obtain the crude product. The crude product was recrystallized twice from n-hexane:toluene = 1:1 (v / v) to give the product C1: 4.1 g, yield: 41%, MS (m / z) (M+): 507.

[0044] Synthesis Example 2

[0045] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compounds A2 (7.4 g, 20 mmol) and B2 (8.4 g, 20 mmol) to finally obtain product C2: 6.2 g (yield: 53%), MS (m / z) (M+): 588.

[0046] Synthesis Example 3

[0047] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compound A3 (5.9 g, 20 mmol) and compound B3 (8.5 g, 20 mmol) to finally obtain product C3: 5.2 g, yield: 50%, MS (m / z) (M+): 516.

[0048] Synthesis Example 4

[0049] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compounds A4 (7.9 g, 20 mmol) and B4 (6.9 g, 20 mmol) to finally obtain product C4: 5.9 g, yield: 55%, MS (m / z) (M+): 535.

[0050] Synthesis Example 5

[0051] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compound A5 (8.4 g, 20 mmol) and compound B5 (6.9 g, 20 mmol) to finally obtain product C5: 5.6 g, yield: 50%, MS (m / z) (M+): 561.

[0052] Synthesis Example 6

[0053] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compound A6 (6.4 g, 20 mmol) and compound B6 (8.4 g, 20 mmol) to finally obtain product C6: 6.2 g, yield: 58%, MS (m / z) (M+): 536.

[0054] Synthesis Example 7

[0055] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compound A7 (6.9 g, 20 mmol) and compound B7 (8.5 g, 20 mmol) to finally obtain product C7: 7.9 g, yield: 70%, MS (m / z) (M+): 565.

[0056] Synthesis Example 8

[0057] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compound A8 (6.9 g, 20 mmol) and compound B8 (8 g, 20 mmol) to finally obtain product C8: 5.6 g, yield: 52%, MS (m / z) (M+): 538.

[0058] Synthesis Example 9

[0059] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compound A9 (7.9 g, 20 mmol) and compound B9 (8 g, 20 mmol) to finally obtain product C9: 6.9 g, yield: 59%, MS (m / z) (M+): 587.

[0060] Synthesis Example 10

[0061] Using the same method as in Synthesis Example 1, compounds A10 (7.9 g, 20 mmol) and B10 (6.9 g, 20 mmol) were substituted for compounds A1 and B1 to finally obtain product C10: 5.6 g, yield: 53%, MS (m / z) (M+): 537.

[0062] Synthesis Example 11

[0063] Using the same method as in Synthesis Example 1, compounds A11 (7.9 g, 20 mmol) and B11 (10.1 g, 20 mmol) were substituted for compounds A1 and B1 to finally obtain product C11: 8.7 g, yield: 63%, MS (m / z) (M+): 692.

[0064] Synthesis Example 12

[0065] Using the same method as in Synthesis Example 1, compounds A1 and B1 were replaced with compounds A12 (8.3 g, 20 mmol) and B12 (8.4 g, 20 mmol) to finally obtain product C12: 8.4 g, yield: 69%, MS (m / z) (M+): 610.

[0066] Synthesis Example 13

[0067] Using the same method as in Synthesis Example 1, compounds A13 (8.7 g, 20 mmol) and B1 (6.9 g, 20 mmol) were substituted for compounds A1 and B1, respectively, to finally obtain product C13: 6.9 g, yield: 64%, MS (m / z) (M+): 535.

[0068] Synthesis Example 14

[0069] Using the same method as in Synthesis Example 1, compounds A14 (9.1 g, 20 mmol) and B14 (6.9 g, 20 mmol) were substituted for compounds A1 and B1 to finally obtain product C14: 6.6 g, yield: 62%, MS (m / z) (M+): 536.

[0070] Comparative compounds .

[0071] Compound / Composition Performance Evaluation 1. Molecular Orientation: The molecular orientation of the material was tested using VASE. The specific steps were as follows: the quartz glass or silicon substrate was ultrasonically cleaned sequentially with deionized water, acetone, and isopropanol for 15 minutes, dried with nitrogen, and then treated with ultraviolet ozone for 15 minutes. Thin films were prepared using vacuum evaporation, with the test compounds / compositions from Table 2 deposited on the substrate at a rate of 1 A / s. The spectral range was selected as 300-800 nm, with a step size of 5 nm, and incident angles of 50°, 60°, and 70° for testing the thin films. The degree of order (S) of the thin films was calculated, with S ranging from -0.5 to 1, where -0.5 represents completely horizontal alignment, 0 represents isotropic alignment, and 1 represents completely vertical alignment.

[0072] The results are shown in Table 2.

[0073] Table 2

[0074] As can be seen from the table above, deuteration substitution of the hydrogen atoms at the ortho position of oxygen promotes the formation of intermolecular hydrogen bonds, which can significantly improve the horizontal molecular orientation of the material after film formation. Furthermore, when the compounds provided by this invention are used in combination, the oxaaryl group, using the same structure, exhibits a high level of horizontal molecular orientation in the film due to its strong orientation-inducing effect. In addition, the test results of compounds D3 and D8 show that fully deuterated molecules, especially those with fully deuterated oxaaryl groups, are unable to effectively form intermolecular hydrogen bonds to improve molecular orientation due to the weakening of intermolecular forces.

[0075] OLED manufacturing and characterization Device Examples The organic electroluminescent device provided by the present invention includes an anode, a hole transport region, an electron transport region of a light-emitting layer, and a cathode sequentially disposed on a substrate. Furthermore, the hole transport region includes a hole injection layer, a hole transport layer, and a light-emitting auxiliary layer; the electron transport region includes an electron transport layer and an electron injection layer.

[0076] Furthermore, the light-emitting layer is composed of a host material and a guest material, and the host material of the light-emitting layer can be composed of one molecular material or multiple molecular materials.

[0077] The compounds described in this invention can be used in the light-emitting layer of the aforementioned organic electroluminescent devices.

[0078] In this embodiment, the anode uses a commonly used anode material in the art, such as ITO, Ag, or their multilayer structures. The hole injection layer uses a commonly used hole injection material in the art, with F4TCNQ, HATCN, NDP-9, etc., added for doping. The hole transport layer uses a commonly used hole transport material in the art. The light-emitting layer uses the host and guest material composition provided by this invention. The electron transport layer uses a commonly used electron transport material in the art. The electron injection layer uses a commonly used electron injection material in the art, such as LiQ, LiF, Yb, etc. The cathode uses a commonly used material in the art, such as metallic Al, Ag, or metal mixtures (Ag-doped Mg, Ag-doped Ca, etc.).

[0079] The electrode fabrication method and the deposition method of each functional layer in this embodiment are conventional methods in the art, such as vacuum thermal evaporation or inkjet printing, and will not be described in detail here. Only some process details and testing methods in the fabrication process are supplemented as follows: Device Example 1 The substrates used in this invention are all subjected to the following operations: the ITO substrate is patterned to give it a light-emitting area of ​​3mm × 3mm, then ultrasonicated with water / isopropanol, irradiated with UV / ozone, and then dried at 100°C. Afterwards, the ITO substrate is mounted on the substrate support of a vacuum deposition apparatus, and the pressure is adjusted to make the vacuum rate 1 × 10⁻⁶. -7 torr.

[0080] The following operations are then performed: First, a hole injection layer is formed on the ITO layer (anode) formed on the substrate by vacuum deposition of compound HTL and compound P-dopant (mass ratio of compound HTL to compound P-dopant is 97:3) with a thickness of 10 nm. Next, a hole transport layer is formed on the hole injection layer by vacuum deposition of compound HTL with a thickness of 120 nm. Then, a light-emitting auxiliary layer is formed on the hole transport layer by vacuum deposition of compound BPrime with a thickness of 5 nm. Next, a light-emitting layer is formed on the light-emitting auxiliary layer by vacuum deposition of a mixture of compound C1 and compound BD from the synthesis example 1 provided in this invention, with a thickness of 20 nm, wherein compound C1 is used as the host material and compound BD is used as the guest material, and the mass ratio of host material to guest material is 98:2. Then, a hole is formed on the light-emitting layer by vacuum deposition of compound HBL with a thickness of 5 nm. A hole-blocking layer is formed. Then, on the aforementioned hole-blocking layer, a 30 nm thick layer of ETL and LiQ compounds (with a mass ratio of ETL to LiQ of 1:1) is vacuum-deposited to form an electron transport layer. Next, on the aforementioned electron transport layer, a 1 nm thick layer of Yb is vacuum-deposited to form an electron injection layer. Then, on the aforementioned electron injection layer, a 15 nm thick layer of Mg and Ag compounds (with a mass ratio of Mg to Ag of 1:9) is deposited to form a cathode. Then, on the aforementioned cathode, a 50 nm thick layer of CPL compound is deposited to form a capping layer. Finally, the vapor-deposited substrate is encapsulated. A UV adhesive coating process is used to coat the cleaned cover plate. The coated cover plate is then moved to the lamination section, and the vapor-deposited substrate is placed on top of the cover plate. Finally, the substrate and cover plate are laminated using a bonding device, while simultaneously curing the UV adhesive under light, thus fabricating a top-emitting organic light-emitting device. The device structure is described in [reference needed]. Figure 1 .

[0081] Except for the main material C1, the molecular structural formulas of the other layers are as follows: .

[0082] Device Examples 2-14 Organic electroluminescent devices were fabricated using the compounds described in other embodiments in Table 3 using the above method. Specifically, blue organic electroluminescent devices Examples 2-14 were fabricated by replacing compound C1 in Device Example 1 with the main material shown in the Device Examples in Table 3.

[0083] Device Comparison Examples 1-14 Organic electroluminescent devices were prepared by using the above method to replace compound C1 in device example 1 with the main material shown in the device comparison examples in Table 3. Specifically, blue organic electroluminescent devices Comparative Examples 1-14 were prepared by replacing compound C1 in device example 1 with the main material shown in the device comparison examples in Table 3.

[0084] Device Composition Examples 1-7 Organic electroluminescent devices were fabricated using the above method with the compositions described in other examples in Table 3. Specifically, blue organic electroluminescent devices Examples 1-7 were fabricated by replacing compound C1 in Device Example 1 with the main material shown in the Device Composition Examples in Table 3.

[0085] Comparative Examples 1-6 of Device Compositions Organic electroluminescent devices were prepared by using the above method to replace the main material shown in the comparative examples in Table 3 with the main material shown in the comparative examples of device compositions in Table 3 to prepare blue organic electroluminescent devices comparative examples 1-6.

[0086] To verify the material's performance at high temperatures, after sample preparation, the sample was first operated under test conditions for 120 hours to fully age, and then characterized. All tests were conducted at 85℃.

[0087] The OLED devices described above were tested using standard methods. For this purpose, J = 10 mA / cm² was used. 2 The driving voltage, luminance, electroluminescence current efficiency (in cd / A), and external quantum efficiency (EQE, in percentage) of the organic electroluminescent device were determined at a given current density, and the emission spectrum was calculated as a function of the emission density from the current / voltage / emission density characteristic line (IVL characteristic line) exhibiting Lambertian emission characteristics.

[0088] Table 3 summarizes the data for various OLED devices. The parameters of the device examples and comparative examples are compared to demonstrate the performance data of the various OLED devices.

[0089] The testing instruments and methods used to perform performance testing on the OLED devices of the above embodiments and comparative examples are as follows: Quantum efficiency (CE) (cd / A), chromaticity coordinates (CIEy), and emission half-width were measured using a PhotoResearch PR-655 spectral scanner. Current density and turn-on voltage: tested using a Keithley 2400 digital source meter; The blue index is obtained by dividing the quantum efficiency CE (cd / A) by the color coordinate (CIEy).

[0090] Table 3

[0091] The device test results above show that the compounds or compositions protected by this invention exhibit better performance in high-temperature tests due to the improved molecular orientation, particularly the enhanced stability of this intermolecular-level molecular orientation caused by intermolecular hydrogen bonds. After the molecular orientation is improved, the driving voltage of the material is significantly reduced, accompanied by a certain degree of efficiency improvement.

[0092] In addition to the improvement in driving voltage and efficiency due to molecular orientation, this invention can significantly improve the broadening of the emission half-width and the unpredictable redshift of the material after device aging by controlling the overall deuteration rate of the material. This phenomenon is particularly evident in device comparative examples 5, 7, 9, and 10, as well as device composition comparative examples 2 and 5.

[0093] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. An organic light-emitting material, characterized in that, The general structural formula of the organic light-emitting material is shown below: I； R1 is selected from any one of phenyl, naphthyl, phenanthryl, pyrene, triphenylene, and biphenyl; R2 is selected from an oxaaryl group, wherein the oxaaryl group is selected from one of the structures shown in formulas a1 to a27 below: a1、 a2、 a3、 a4、 a5、 a6、 a7、 a8、 a9、 a10、 a11、 a12、 a13、 a14、 a15、 a16、 a17、 a18、 a19、 a20、 a21、 a22、 a23、 a24、 a25、 a26、 a27; Ar 21 To Ar 29 Each is independently selected from hydrogen or phenyl; In Formula I, any hydrogen atom other than the groups a1 to a27 can be substituted with deuterium.

2. The organic light-emitting material according to claim 1, characterized in that, R2 is selected from one of the following structures: 、 、 、 、 、 、 、 、 。 3. The organic light-emitting material according to claim 1, characterized in that, The organic light-emitting material is selected from the structure shown below: 。 4. An organic electroluminescent device, characterized in that, It includes an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; wherein the light-emitting layer comprises one or more organic light-emitting materials as described in any one of claims 1 to 3.

5. The organic electroluminescent device according to claim 4, characterized in that, The light-emitting layer comprises a host material and a guest material, wherein the host material comprises one or more organic light-emitting materials as described in any one of claims 1 to 3.

6. The organic electroluminescent device according to claim 5, characterized in that, The main material comprises at least two organic light-emitting materials as described in any one of claims 1 to 3, wherein the two organic light-emitting materials are respectively selected from formula I-1 and formula I-2: I-1、 I-2; R 1-1 R 1-2 Each is independently selected from any one of phenyl, naphthyl, phenanthrene, pyrene, triphenylene, and biphenyl; R 2-1 R 2-2 Oxaaryl groups representing the same or different general structural formulas are each independently selected from one of formulas a1-a8; or R 2-1 R 2-2 Selected from formula a9 or formula a10; or R 2-1 R 2-2 Selected from formula a11 or formula a12; or R 2-1 R 2-2 Selected from formula a13 or formula a14; or R 2-1 R 2-2 Selected from formula a15 or formula a16; or R 2-1 R 2-2 Selected from formula a17 or formula a18; or R 2-1 R 2-2 Selected from formula a19 or formula a20; or R 2-1 R 2-2 Selected from formula a21 or formula a22; or R 2-1 R 2-2 Selected from formula a23 or formula a24; or R 2-1 R 2-2 Selected from formula a25 or formula a26; or R 2-1 R 2-2 Selected from formula a27.

7. The organic electroluminescent device according to claim 5, characterized in that, The main material includes at least one of the following combinations: Combination 1: ; Combination 2: ; Combination 3: ; Combination 4: ; Combination 5: ; Combination 6: ; Combination 7: ; Combination 8: ; Combination 9: ; Combination 10: ; Combination 11: ; Combination 12: ; Combination 13: ; Combination 14: ; Combination 15: ; Combination 16: ; Combination 17: ; Combination 18: ; Combination 19: ; Combination 20: ; Combination 21: ; Combination 22: ; Combination 23: ; Combination 24: ; Combination 25: . Combination 26: Combination 27: Combination 28: Combination 29: .

8. The organic electroluminescent device according to claim 7, characterized in that, The mass ratio of the two compounds in combinations 1 to 29 is 2:8 to 8:

2.

9. A display device, characterized in that, Includes the organic electroluminescent device according to any one of claims 4-8.

10. A lighting device, characterized in that, Includes the organic electroluminescent device according to any one of claims 4-8.

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