An organic electroluminescence dopant material and an organic electroluminescence device

Abstract

The application provides an organic electroluminescent doping material and an organic electroluminescent device, the organic electroluminescent doping material has a structure shown in formula I, and after the organic electroluminescent doping material is used in the organic electroluminescent device, the starting voltage of the device is reduced, and the luminous efficiency and the service life of the device are improved.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronic device technology and relates to an organic electroluminescent doped material and an organic electroluminescent device. Background Technology

[0002] Organic light-emitting diodes (OLEDs), also known as organic electroluminescent displays or organic light-emitting semiconductors, refer to the phenomenon where organic semiconductor materials and light-emitting materials emit light through carrier injection and recombination under an electric field. OLEDs are organic electroluminescent devices composed of specialized organic materials. Based on their structure, they can be classified into four types: single-layer devices, double-layer devices, triple-layer devices, and multi-layer devices. Multi-layer structures offer superior performance, effectively utilizing the functions of each layer. The light-emitting layer can also consist of multiple layers; because each layer is independent, it can be optimized separately. Therefore, this structure fully leverages the function of each organic layer, greatly improving the flexibility of device design.

[0003] The most important factor determining the luminescence efficiency of organic EL devices is the luminescent material. Luminescent materials have evolved through two generations, with fluorescent materials now widely used. However, first-generation fluorescent materials utilize singlet excitons, resulting in low internal quantum efficiency, reaching a maximum of only 25%. Second-generation phosphorescent materials utilize triplet excitons, theoretically achieving 100% efficiency.

[0004] However, existing phosphorescent materials used in organic light-emitting devices suffer from low efficiency and short lifespan. Therefore, providing an organic electroluminescent material with long lifespan, high efficiency, and low driving voltage is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an organic electroluminescent doped material and an organic electroluminescent device. This invention introduces a carbazole group onto the ligand, giving the compound a more rigid planar conjugated structure, improving the intermolecular symmetric dipole moment, and simultaneously enhancing the phosphorescence quantum efficiency and electroluminescence efficiency of the material. Furthermore, the carbazole aromatic structure is modified with alkyl chains, cycloalkyl groups, aryl groups, and heteroalkyl groups, greatly enhancing the thermal and photostability of the structure. This results in an organic compound used in organic electroluminescent devices that lowers the device's startup voltage and improves its luminescence efficiency and lifetime.

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

[0007] On one hand, the present invention provides an organic electroluminescent doped material having the structure shown in Formula I:

[0008]

[0009] X is one of N, O, S, Si, Ge, C, or Se;

[0010] R1-R8 are each independently selected from -H, -D, -T, -F, -CN, -CH3, -CD3, -CT3, -CF3, -CH2F, -CHF2, substituted or unsubstituted C2-C24 alkyl, substituted or unsubstituted C3-C24 cycloalkyl, substituted or unsubstituted C6-C24 aryl and substituted or unsubstituted 4-24 heterocyclic groups;

[0011] R9-R 25 Each is independently selected from any one of -H, -D, -T, -F, -CN, -CH3, -CD3, -CT3, -CF3, -CH2F, -CHF2, -SiMe3, -GeMe3, substituted or unsubstituted C2-C24 alkyl, substituted or unsubstituted C3-C24 cycloalkyl, substituted or unsubstituted C6-C24 aryl and substituted or unsubstituted 4-24 heterocyclic groups;

[0012] R1-R 25 Each exists independently, or at least one of them interacts with other substituents on the ring to form substituted or unsubstituted C3-C24 aliphatic rings, substituted or unsubstituted C6-C24 aromatic rings, substituted or unsubstituted C4-C24 aromatic heterocycles, or substituted or unsubstituted C10-C24 fused rings.

[0013] The substituents in the substituted groups are selected from one or a combination of at least two of the following: -H, -D, -T, -F, -CN, -CH3, -CD3, -CT3, -CF3, -CH2F, -CHF2, -SiMe3, and -GeMe3.

[0014] The heteroatom in the heterocyclic group is at least one of N, O, or S;

[0015] In Formula I, hydrogen is either unsubstituted by deuterium, partially substituted by deuterium, or completely substituted by deuterium.

[0016] D represents deuterium, T represents tritium, and Me represents methyl.

[0017] More preferably, X is selected from O or S.

[0018] Preferably, R1-R8 are each independently selected from any one or a combination of at least two of the following groups: -H, -D, -T, -F, -CN, -CH3, -CD3, -CT3, -CF3, -CH2F, -CHF2, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, tetrahydrofuran, thiacyclopentane, tetrahydropyran, phenyl, Biphenyl, deuterated phenyl, bideuterated phenyl, triphenyl, naphthyl, fluorenyl, phenanthryl, anthracene, indyl, triphenylene, pyrene, tetraphenyl, perylene, trefyl, fused tetraphenyl, fluoranthyl, carbazolyl, furanyl, thiophene, imidazolyl, thiazolyl, pyridinyl, pyrimidinyl, benzofuranyl, benzothiophene, isobenzofuranyl, dibenzofuranyl, dibenzothiophene, benzimidazolyl, benzothiazolyl, quinolinyl, isoquinolinyl or the following substituents;

[0019]

[0020] The asterisk (*) represents the linking site of a functional group.

[0021] Preferably, R9-R 25 Each group is independently selected from any one or at least two combinations of the following groups: -H, -D, -T, -F, -CN, -CH3, -CD3, -CT3, -CF3, -CH2F, -CHF2, -SiMe3, -GeMe3, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, tetrahydrofuran, thiacyclopentane, tetrahydropyran, Phenyl, biphenyl, deuterated phenyl, bideuterated phenyl, triphenyl, naphthyl, fluorenyl, phenanthryl, anthracene, indyl, triphenylene, pyrene, tetraphenyl, perylene, trefyl, fused tetraphenyl, carbazole, fluoranyl, furanyl, thiophene, imidazolyl, pyrazolyl, thiazolyl, triazinyl, pyridyl, pyrazinyl, pyrimidinyl, benzofuranyl, benzothiophene, dibenzofuranyl, dibenzothiophene, benzo-m-dioxacyclopentenyl or the following substituents;

[0022]

[0023] Where * represents the linkage site of a functional group;

[0024] R' is independently selected from any one or a combination of at least two of -H, -D, -T, -F, -CN, -CH3, -CD3, -CT3, -CF3, -CH2F, -CHF2, -SiMe3, -GeMe3, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, biphenyl, deuterated phenyl, bideuterated phenyl, naphthyl, benzofuranyl, benzothiophenyl, furanyl, thiophenyl, dibenzofuranyl or dibenzothiophenyl;

[0025] Preferably, R1-R 25 At least one of them interacts with other substituents on the ring to form cyclopentyl, cyclohexyl, benzene ring, naphthyl ring, benzofuranyl, benzothiophenyl, furanyl, thiophenyl, dibenzofuranyl, dibenzothiophenyl, etc., or a combination of at least two of the above groups.

[0026] More preferably, the organic electroluminescent dopant material is any one of the following compounds:

[0027]

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[0065]

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[0067]

[0068] In this invention, the preparation process of the compound with the structure of Formula I is as follows:

[0069]

[0070] The limitations in the above formula are the same as those mentioned above, and will not be repeated here.

[0071] On the other hand, the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising an anode, a cathode and an organic material layer disposed between the anode and the cathode, the organic material layer comprising at least one of the organic electroluminescent doping materials as described above.

[0072] Preferably, the organic material layer includes a light-emitting layer, which includes a host material and a dopant material, wherein the dopant material includes at least one of the organic electroluminescent dopant materials as described above.

[0073] Preferably, the organic material layer further includes at least one of a hole injection layer, a hole transport layer, an electron blocking layer, an electron transport layer, or an electron injection layer.

[0074] Preferably, the organic electroluminescent device comprises an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode arranged sequentially.

[0075] Generally, an organic electroluminescent device includes a first electrode (anode) and a second electrode (cathode), as well as an organic material layer located between the electrodes. This organic material can be further divided into multiple regions. For example, the organic material layer may include a hole transport region, a light-emitting layer, and an electron transport region.

[0076] In specific embodiments, a substrate can be used below the first electrode or above the second electrode. The substrate is typically made of glass or polymer material with excellent mechanical strength, thermal stability, water resistance, and transparency. Furthermore, thin-film transistors (TFTs) can also be incorporated into the substrate used for displays.

[0077] The first electrode can be formed by sputtering or depositing a material used as the first electrode on a substrate. When the first electrode is used as the anode, transparent conductive oxide materials such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), and zinc oxide (ZnO), and any combination thereof, can be used. Furthermore, the anode material can also be selected from materials and combinations thereof that facilitate hole injection, in addition to the anode materials listed above, including known materials suitable for anodes. When the first electrode is used as the cathode, metals or alloys such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag), and any combination thereof, can be used. Besides the cathode materials listed above, the cathode material can also be materials and combinations thereof that facilitate electron injection, including known materials suitable for cathodes.

[0078] The organic material layer can be formed on the electrode using methods such as vacuum thermal evaporation, spin coating, and printing. The compounds used as the organic material layer can be small organic molecules, large organic molecules, polymers, and combinations thereof. The hole transport region is located between the anode and the light-emitting layer. The hole transport region can be a monolayer hole transport layer (HTL), including monolayer hole transport layers containing only one compound and monolayer hole transport layers containing multiple compounds. The hole transport region can also be a multilayer structure including at least one of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL).

[0079] The material of the hole transport layer may be selected from, but is not limited to, phthalocyanine derivatives such as CuPc, conductive polymers or polymers containing conductive dopants such as polyphenylene ethylene, polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphorsulfonic acid (PANI / CSA), polyaniline / poly(4-styrenesulfonate) (PANI / PSS), aromatic amine derivatives as shown in HT-1 to HT-34 below; or any combination thereof.

[0080]

[0081]

[0082]

[0083] However, it is not limited to the above-mentioned materials.

[0084] The hole injection layer is located between the anode and the hole transport layer. The hole injection layer can be a single compound material or a combination of multiple compounds. For example, the hole injection layer can use one or more compounds from HT-1 to HT-34, or one or more compounds from HI-1 to HI-3; alternatively, one or more compounds from HT-1 to HT-34 can be doped with one or more compounds from HI-1 to HI-3.

[0085]

[0086] However, it is not limited to the above-mentioned materials.

[0087] The organic material layer of an OLED may also include an electron transport region between the light-emitting layer and the cathode.

[0088] The emissive layer may include luminescent dyes (i.e., dopants) that emit different wavelengths of light, and may also include a host material. The emissive layer can be a monochromatic emissive layer emitting a single color such as red, green, or blue. Multiple monochromatic emissive layers of different colors can be arranged in a planar pattern according to pixel design, or they can be stacked together to form a colored emissive layer. When different colored emissive layers are stacked together, they can be separated from each other or connected to each other. The emissive layer can also be a single-color emissive layer that simultaneously emits different colors such as red and green.

[0089] Depending on the technology used, the light-emitting layer material can be different, such as phosphorescent photoluminescent materials and thermally activated delayed fluorescence materials. An OLED device can employ a single light-emitting technology or a combination of different light-emitting technologies. These different light-emitting materials, categorized by technology, can emit light of the same color or different colors.

[0090] Formula I of this invention is used as the doping material in the light-emitting layer.

[0091] The electron transport region can be a single-layer electron transport layer (ETL), including a single-layer electron transport layer containing only one compound and a single-layer electron transport layer containing multiple compounds. The electron transport region can also be a multilayer structure including at least one of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL).

[0092] In one aspect of the present invention, the electron transport layer material may be selected from, but not limited to, one or more combinations of ET-1 to ET-57 listed below.

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[0094]

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[0096]

[0097]

[0098] However, it is not limited to the above-mentioned materials.

[0099] The device may also include an electron injection layer located between the electron transport layer and the cathode. The electron injection layer material includes, but is not limited to, one or more combinations of the following: LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, and Ca.

[0100] Compared with the prior art, the present invention has the following beneficial effects:

[0101] By adjusting different L A By altering the structure of the ligand (i.e., the ligand on the left side of Formula I), and modifying some electrons and functional groups, the spatial structure of the molecule is changed, improving the spin-orbit coupling effect of the luminescent molecule, thus making it more conducive to phosphorescence generation and enhancing its quantum efficiency. Simultaneously, in L... B By introducing a carbazole group onto the ligand (i.e., the ligand on the right side of Formula I), the compound of the present invention has a better rigid planar conjugated structure compared with the comparative compound, which improves the intermolecular symmetric dipole moment and improves the phosphorescence quantum efficiency and electroluminescence efficiency of the material. At the same time, the carbazole aromatic structure is greatly enhanced in terms of thermal stability and photostability through modification with alkyl chains, cycloalkyl, aryl and heteroalkyl groups. As a doping material of the light-emitting layer, the organic electroluminescent device prepared by the compound of the present invention has a significantly lower driving voltage and significantly improved luminescence efficiency and lifetime compared with the organic electroluminescent device prepared by the comparative example. Attached Figure Description

[0102] Figure 1 The NMR spectrum of the compound with structural formula I-76 is shown. Detailed Implementation

[0103] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0104] Example 1

[0105] This synthetic example provides an organometallic compound I-76, i.e., compound numbered I-76, and the specific synthetic steps are as follows:

[0106]

[0107] Under nitrogen protection, 2-(6-chlorodibenzo[b,d]furan-4-yl)pyridine (CAS: 2888618-84-4, 1.0 eq), pinacol diborate (1.5 eq), X-Phos (0.12 eq), palladium acetate (0.02 eq), potassium acetate (3 eq), and dioxane were added sequentially to the reaction system. The mixture was substituted with N2 three times and protected with N2, and heated and stirred overnight at 100°C. After the reaction was complete, the mixture was filtered through diatomaceous earth and anhydrous magnesium sulfate, washed twice with ethyl acetate, and the organic phase was collected and concentrated under reduced pressure to obtain the crude intermediate of formula L. BⅢ -76 is used directly for the next step.

[0108]

[0109] Under nitrogen protection, 1-bromo-2-nitrobenzene (CAS: 577-19-5, 1.0 eq) was weighed, with the intermediate formula L. BⅢ -76 (1.2 eq) and anhydrous potassium carbonate (3.0 eq) were added to the reaction system, followed by toluene, anhydrous ethanol, and purified water. Pd(PPh3)4 (0.02 eq) was added under nitrogen protection. The mixture was refluxed at 100°C for 26 h under nitrogen protection, then cooled to 25°C. After cooling, the mixture was extracted with ethyl acetate, washed three times with saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The crude product was then subjected to column chromatography (200–300 mesh) with an eluent of EA:PE = 1:10 to remove impurities. The receiving liquid was vortexed until no liquid flowed out, and then dried under vacuum to obtain the intermediate L of the compound shown. BⅡ -76 (yield 68%), with an HPLC purity greater than 99.5%.

[0110] Mass spectrometry test value: 366.42.

[0111]

[0112] Under nitrogen protection, weigh out compound L BⅡ -76 (1.0 eq) was dissolved in o-dichlorobenzene, and triphenylphosphine (1.2 eq) was added under nitrogen protection. The mixture was refluxed for 24 h. After the reaction was completed, the solvent was evaporated, and the crude product was subjected to column chromatography (200-300 mesh) with EA:PE = 1:15 as the developing solvent to remove impurities. The receiving liquid was evaporated until no liquid flowed out, and then dried under vacuum to obtain the intermediate L of the compound shown. BⅠ -76 (yield 59%), with an HPLC purity greater than 99.5%.

[0113] Mass spectrometry value: 334.37.

[0114]

[0115] Under nitrogen protection, weigh out the intermediate L of the compound. BⅠ -76 (1.0 eq), bromobenzene (CAS: 108-86-1) (1.2 eq), and sodium tert-butoxide (2.0 eq) were added to the reaction system, followed by toluene. Pd2(dba)3 (0.04 eq) and PPh3 (0.1 eq) were added under nitrogen protection. The mixture was refluxed at 100 °C for 24 h under nitrogen protection, then cooled to 25 °C. After cooling, the mixture was extracted with ethyl acetate, washed three times with saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The crude product was then subjected to column chromatography (200–300 mesh) with EA:PE = 1:8 as the developing solvent to remove impurities. The receiving liquid was vortexed until no liquid flowed out, and then dried under vacuum to obtain the intermediate L of the compound shown. B -76 (yield 76%), with an HPLC purity greater than 99.5%.

[0116] Mass spectrometry value: 410.35.

[0117]

[0118] Under nitrogen protection, weigh ligand L A -76(5-methyl-2-phenylpyridine) (CAS:3256-88-0) (2.4 eq) and IrC13·3H2O (1.0 eq) were added to the reaction system, along with a mixed solution of ethylene glycol ethyl ether and purified water. The mixture was refluxed under nitrogen protection for 28 hours, then cooled to room temperature. A precipitate was formed. The precipitate was filtered, washed sequentially with water, anhydrous ethanol, and petroleum ether, and then dried.

[0119] The bridging ligand III-76 shown was obtained (yield 63%).

[0120]

[0121] Weigh 1.0 eq of intermediate formula III-76, add 2.5 eq of silver trifluoromethanesulfonate, then add dichloromethane and methanol to the system. Under nitrogen protection, reflux for 26 hours, cool to room temperature, and concentrate the filtrate by column chromatography (short column) until a solid precipitates. The iridium complex intermediate formula II-76 shown is obtained (yield 86%).

[0122]

[0123] Weigh out intermediate formula II-76 (1.0 eq) and add ligand formula L. B -76 (2.5 eq), then anhydrous ethanol was added to the system, and the mixture was refluxed for 36 hours under nitrogen protection. The mixture was then filtered, washed with ethanol, and dried. Dichloromethane was used as a solvent for silica gel column chromatography. The filtrate was concentrated to precipitate the solid, yielding the final compound I-76 (yield 35%).

[0124] The organometallic compound I-76 was subjected to the following analytical tests:

[0125] HPLC purity: greater than 99.5%;

[0126] The mass spectrometry value was 938.48.

[0127] Elemental analysis: Test values ​​are C, 67.88; H, 3.99; N, 5.98; O, 1.72.

[0128] The proton NMR spectrum of compound I-76 is as follows: Figure 1 As shown.

[0129] The synthesis methods for other compounds are the same as those described above, and will not be repeated here.

[0130] The present invention also provides an organic electroluminescent device, wherein the organic electroluminescent device is made of the aforementioned organic light-emitting material, more specifically, it is made of an organic light-emitting material of a compound with chemical formula I.

[0131] Device Example 1

[0132] Compound I-1 prepared in this invention was selected as the phosphorescent material with a doping ratio of 5% to prepare OLED devices. The specific preparation method is as follows:

[0133] (1) The glass plate coated with ITO transparent conductive layer was ultrasonically treated in commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in acetone: ethanol mixed solvent (volume ratio 1:1), baked in a clean environment until the moisture was completely removed, cleaned with ultraviolet light and ozone, and bombarded with low-energy cation beam.

[0134] (2) Place the glass substrate with the anode into the vacuum chamber and evacuate to 1×10⁻⁶. -5 ~9×10 -3 Pa, HI-3 is vacuum-deposited on the above-mentioned anodic layer as a hole injection layer at a deposition rate of 0.1 nm / s and a total film thickness of 10 nm; then the first hole layer HT-5 is deposited at a deposition rate of 0.1 nm / s and a thickness of 60 nm; then the electron blocking layer EB-1 is deposited at a deposition rate of 0.1 nm / s and a film thickness of 5 nm.

[0135] (3) Vacuum evaporation of EML on hole transport layer as light-emitting layer of device. EML includes host material GH-1 and doping material I-1 of the present invention. The doping mass percentage concentration is 5%. It forms organic light-emitting layer of device. Evaporation rate is 0.2nm / s. Total evaporation film thickness is 30nm.

[0136] (4) ET-15:LiQ with a mass ratio of 1:1 was deposited on the hole blocking layer as the electron transport material of the device electron transport layer. The deposition rate was 0.1 nm / s and the total film thickness was 30 nm.

[0137] (5) A 1 nm thick LiF layer was sequentially vacuum-deposited on the electron transport layer as an electron injection layer, and a 150 nm thick Al layer was deposited as the cathode of the device. After encapsulation, an OLED device was obtained. The performance and luminous characteristics of the obtained device were tested using a KEITHLEY 2400 source measurement unit and a CS-2000 spectroradiometer to evaluate the driving voltage, lifetime, and luminous efficiency.

[0138] The structure used is as follows:

[0139]

[0140] Device Comparison Examples 1-6

[0141] Organic electroluminescent devices were prepared using the same method as in Device Example 1, except that the doping compound I-1 in Device Example 1 was replaced with the structural compounds of Comparative Examples 1-6.

[0142]

[0143] The prepared organic electroluminescent devices were subjected to the same tests as in Example 1, and the results are shown in Table 1.

[0144] Device Examples 2-48

[0145] The method described in Example 1 of the above device is the same, except that the doping material I-1 is replaced with the corresponding compound in Table 1.

[0146] The driving voltage, luminous efficiency, and lifetime of the organic electroluminescent devices obtained from the above-mentioned device embodiments and device comparative examples were characterized at a brightness of 8000 nits. The test results are shown in Table 1 below.

[0147] Table 1

[0148]

[0149]

[0150] By comparing comparative compounds 1-6 with the organometallic compounds of the present invention, it can be seen that L B By introducing carbazole-type groups onto dibenzofuran, the compounds of this invention exhibit a more rigid planar conjugated structure compared to the comparative compounds. This structure effectively suppresses intermolecular π-π stacking, reduces energy level transition losses, optimizes HOMO and LUMO energy levels, induces electron charge transfer excited states, enhances spin-orbit coupling, increases transition dipole moments, and significantly improves the luminous efficiency of the material while reducing its turn-on voltage. Furthermore, the carbazole-based aromatic structure, modified with alkyl chains, greatly enhances the thermal and photostability of the structure, resulting in a significant increase in its lifetime. As shown in the table above, the organic electroluminescent devices prepared using the compounds of this invention as luminescent layer doping materials exhibit significantly lower driving voltages, and significantly improved luminous efficiency and lifetime compared to the organic electroluminescent devices prepared in the comparative examples.

[0151] A comparison of comparative compounds 1-6 with the organometallic compounds of this invention shows that by adjusting different L... ABy altering the structure of the ligands, including some electrons and functional groups, the molecular spatial structure is changed, improving the spin-orbit coupling effect of the luminescent molecules. This makes them more conducive to phosphorescence generation and enhances their quantum efficiency. As a doping material for the luminescent layer, the organic electroluminescent devices prepared with the compounds of this invention exhibit significantly lower driving voltage, significantly improved luminous efficiency, and significantly higher lifetime compared to those prepared in the comparative examples. Moreover, these figures exceed any value attributable to experimental error.

[0152] Specifically, compared with the compound of Comparative Example 3, the compound of Example I-87 of this invention only replaces the -SiMe3 group of the dual ligand with the -Me group, which directly affects the carrier mobility, balances solubility and ordered propulsion, promotes efficient charge transport, and optimizes exciton utilization by adjusting molecular orientation and energy level matching, so that compared with the comparative example, it has lower voltage, higher lifetime and higher efficiency.

[0153] The above embodiments only list the effect data of devices made from a portion of the structures. This is a representative sampling test. Based on the experimental data, the overall data is not significantly different and can represent the effects of other unlisted structures.

[0154] The applicant declares that the organic electroluminescent material and organic electroluminescent device of the present invention are illustrated through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. An organic electroluminescent doped material, characterized in that, The organic electroluminescent doped material has the structure shown in Formula I: ； X is either O or S; R1-R8 are each independently selected from any one or at least two combinations of the following groups: -H, -CH3, -CD3, ethyl, isopropyl, tert-butyl, phenyl, deuterated phenyl, or , Where * represents the linkage site of a functional group; R9-R 12 Each of the following substituents is independently selected from any one or a combination of at least two of the following: selected from hydrogen, -CH3, -CD3, -F, -CF3, -SiMe3, -GeMe3, ethyl, n-propyl, n-butyl, phenyl, naphthyl, carbazole, or the following substituents; ； Where * represents the linkage site of a functional group; R 13 -R 17 Each group is independently selected from any one or at least a combination of two of the following groups: -H, -D, -CH3, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, phenyl, or forms a naphthalene ring with other substituents on the ring; R 18 -R 25 Each group is independently selected from any one or at least two of the following groups: -H, -CH3, or , where * represents the linking site of the group.

2. An organic electroluminescent doped material, characterized in that, The organic electroluminescent dopant material is selected from any one of the following compounds: 。 3. An organic electroluminescent device, characterized by comprising The organic electroluminescent device includes an anode, a cathode, and an organic material layer disposed between the anode and the cathode, wherein the organic material layer includes at least one of the organic electroluminescent doped materials according to claim 1 or 2.

4. The organic electroluminescent device according to claim 3, characterized in that The organic material layer includes a light-emitting layer, which comprises a host material and a dopant material, wherein the dopant material comprises at least one of the organic electroluminescent dopant materials according to claim 1 or 2.

5. The organic electroluminescent device according to claim 3, characterized in that, The organic material layer further includes at least one of a hole injection layer, a hole transport layer, an electron blocking layer, an electron transport layer, or an electron injection layer.

6. The organic electroluminescent device according to claim 4, characterized in that, The organic electroluminescent device comprises an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode arranged sequentially.

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