Phosphorescent dopant materials and organic electroluminescent devices containing the same

Abstract

The application belongs to the technical field of organic electroluminescent materials, and discloses a phosphorescent doping material and an organic electroluminescent device containing the same. n The parent nucleus of the main ligand in the phosphorescent doping material is an aza-phenanthrene ring and a naphthalene ring substituted at a specific position, and the compound in the general formula of the application has a large oscillator strength S m excitation energy level. After absorbing external energy, the molecule can be efficiently excited, and before relaxing to the S1 energy level, the energy is transferred to the surrounding T n state through intersystem crossing, thereby fully supplying the triplet state, and finally participating in the luminescence process through the "borrowing effect" of S m and T , thereby obtaining more excellent luminescent efficiency characteristics. In addition, the device prepared from the compound in the general formula of the application has excellent overall performance, a lower driving voltage, and a longer device life.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials technology, specifically relating to a phosphorescent doped material and an organic electroluminescent device containing the same, and particularly to a phosphorescent doped material having a naphthalene ring ligand substituted with a cyano group at a specific position and its application. Background Technology

[0002] Organic light-emitting diodes (OLEDs), as a next-generation display and lighting technology, have become a research hotspot in industry and academia due to their advantages such as self-emission, high contrast, and flexibility. OLEDs convert electrical energy into light by applying electricity to organic electroluminescent materials and typically include an anode, a cathode, and an organic layer formed between or outside the two electrodes. This organic layer can contain hole injection layers, hole transport layers, light-emitting auxiliary layers, electron blocking layers, light-emitting layers, electron buffer layers, hole blocking layers, electron transport layers, electron injection layers, and capping layers.

[0003] In OLED light-emitting layer materials, phosphorescent transition metal complexes (such as iridium complexes) are key materials for high-performance OLED devices because they can utilize singlet and triplet excitons and theoretically achieve 100% internal quantum efficiency, which is significantly better than traditional fluorescent materials.

[0004] Currently, there are many reports on iridium complex phosphorescent doped materials, but it is difficult to achieve a good balance between driving voltage, luminous efficiency and lifetime. Therefore, developing stable and efficient phosphorescent doped materials that can perform well in terms of overall device performance has important practical application value. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a phosphorescent doped material, its preparation method and organic electroluminescent device. When the phosphorescent doped material is applied to the organic electroluminescent device, it exhibits the characteristics of low driving voltage, high luminous efficiency and long lifetime, and the overall performance of the device is better.

[0006] To achieve this objective, the present invention adopts the following technical solution: On one hand, the present invention provides a phosphorescent doped material, wherein the chemical formula of the phosphorescent doped material is Ir(L a )2(L b )1, of which ligand L a It has the general formula structure shown in Formula 1 or Formula 2: , in, R1 and R3 are each independently selected from hydrogen, deuterium, boron, halogen, cyano, trimethylsilyl, trimethylgermanyl, nitro, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C6-C24 aryl, substituted or unsubstituted C6-C18 heteroaryl, and their heteroatoms contain at least one of O, S, N, Si, Ge, and Se. m and n are each independently selected from 0, 1, 2, 3, 4, 5, 6, 7 or 8. When m and n are greater than 1, multiple R1 and R3 are the same or different from each other. R2 and R4 are each independently selected from boron, halogen, cyano, trimethylsilyl, trimethylgermanyl, nitro, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C6-C24 aryl, substituted or unsubstituted C5-C18 heteroaryl, and their heteroatoms contain at least one of O, S, N, Si, Ge, and Se. ligand L b It has the structure shown in Equation 3: ; R5, R6, and R7 are each independently selected from hydrogen, deuterium, halogen, cyano, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C15 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C6-C18 aryl, and substituted or unsubstituted C6-C18 heteroaryl, wherein their heteroatoms contain at least one of O, S, N, Si, Ge, and Se.

[0007] In one embodiment of the present invention, R1 and R3 are each independently selected from hydrogen, deuterium, halogen, cyano, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C6-C10 heteroaryl, and their heteroatoms contain at least one of O, S, N, Si, Ge, and Se. R2 and R4 are each independently selected from halogens, cyano groups, trimethylsilyl groups, trimethylgermanyl groups, substituted or unsubstituted C1-C6 alkyl groups, substituted or unsubstituted C3-C6 cycloalkyl groups, substituted or unsubstituted C6-C18 aryl groups, and substituted or unsubstituted C6-C10 heteroaryl groups, wherein their heteroatoms contain at least one of O, S, N, Si, Ge, and Se.

[0008] In one embodiment of the present invention, R5, R6, and R7 are each independently selected from hydrogen, deuterium, halogen, cyano, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C7 alkyl, substituted or unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted C6-C12 aryl, substituted or unsubstituted C2-C9 heteroaryl, and their heteroatoms contain at least one of O, S, N, Si, Ge, and Se.

[0009] In one embodiment of the present invention, R1 and R3 are each independently selected from the following structures: , “ "" indicates the binding sites of R1-R4 with carbon on the ring.

[0010] In one embodiment of the present invention, R2 and R4 are each independently selected from the following structures: , “ "" indicates the binding sites of R1-R4 with carbon on the ring.

[0011] In one embodiment of the present invention, formulas 1 and 2 include the following structures: ; In the above technical solutions, the term "substituted or unsubstituted" means substituted by one, two or more of the following substituents: deuterium, -CN, -F, -Cl, -Br, C1-C4 alkyl, C3-C6 cycloalkyl, C1-C4 heteroalkyl (the heteroatom in the heterocycloalkyl is selected from O, S, N, Si or Ge) or without substituents.

[0012] In one embodiment of the present invention, the phosphorescent doping material has any one of the following compounds, but is not limited thereto:

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051] The second objective of this invention is to provide a method for preparing the phosphorescent doped material as described above.

[0052] It should be noted that the phosphorescent doped material described in this invention can be prepared by methods known to those skilled in the art, or preferably prepared by the following reaction process, the specific synthesis route of which is as follows:

[0053]

[0054] ; (1) Under N2 protection, reactant 1-a (1.0 eq), reactant 1-b (1.1-1.3 eq), palladium catalyst (0.01-0.02 eq) and base (2.0-2.3 eq) were added to a mixed solvent of toluene, ethanol and water (2-4:1:1), respectively. The mixture was heated to 80-100℃ and reacted for 6-8 h. After cooling to room temperature, water was added. After the solid precipitated completely, the mixture was filtered, the filter cake was dried, and purified by column chromatography. The solvent in the filtrate was removed by a rotary evaporator, and the obtained solid was dried to obtain reactant 1-c.

[0055] (2) Under N2 protection, reactants 1-c (1.0 eq), 1-d (1.5-2.0 eq), palladium catalyst (0.05-0.1 eq), and potassium acetate (2.0-3.0 eq) were dissolved in N,N-dimethylformamide. The mixture was heated to 85-95℃ and reacted for 8-10 h. The solvent was removed using a rotary evaporator. The residue was added to dichloromethane, stirred, filtered, and purified by column chromatography to obtain reactant 1-e.

[0056] (3) Under N2 protection, reactant 1-e (1.0 eq), reactant 1-f (1.1-1.3 eq), palladium catalyst (0.01-0.02 eq) and base (2.0-2.3 eq) were added to a mixed solvent of toluene, ethanol and water (volume ratio of 2-4:1:1), respectively. The mixture was heated to 80-100℃ and reacted for 6-8 h. After cooling to room temperature, water was added. After the solid precipitated completely, the mixture was filtered, the filter cake was dried, and purified by column chromatography. The solvent in the filtrate was removed by a rotary evaporator, and the obtained solid was dried to obtain reactant 1-g.

[0057] (4) Under N2 protection, 1 g (1.0 eq) of reactant was dissolved in a mixed solution of 2-ethoxyethanol and water (volume ratio 3:1), and the mixture was degassed with nitrogen for 15-20 minutes. Then IrCl3·4H2O (0.3-0.5 eq) was added, and the mixture was refluxed under N2 protection for 20-24 hours. The mixture was then cooled to room temperature, and a precipitate was formed. The precipitate was filtered, washed sequentially with water, anhydrous ethanol, and petroleum ether, and dried under vacuum to obtain intermediate 1 h.

[0058] (5) Under N2 protection, intermediate 1-h (1.0 eq) and reactant 1-i (8.0-11.0 eq) were added to a 2-ethoxyethanol solution, while the mixture was degassed with N2 for 15-20 minutes. Then anhydrous potassium carbonate (8.0-11.0 eq) was added, and the mixture was refluxed under nitrogen protection for 20-24 hours. After cooling, the mixture was filtered, washed with alcohol, and dried. Using dichloromethane as a solvent, the mixture was subjected to neutral alumina column chromatography. The filtrate was concentrated to precipitate the solid, finally yielding complex 1.

[0059] The synthesis method of complex 2 is similar to that of complex 1, by simply replacing reactants 1-a and 1-b with reactants 2-a and 2-b respectively.

[0060]

[0061]

[0062] in, Hal and Hal1 are independently selected from F, Cl, Br, or I; B is boric acid or pinacol diboronic acid ester; B' is... or , R1-R7, m and n have the definitions given above; The palladium catalyst can be: Pd2(dba)3, Pd(PPh3)4, PdCl2, PdCl2(dppf), Pd(OAc)2 or Pd(PPh3)2Cl2; The base can be: K2CO3, K3PO4, Na2CO3, CsF, Cs2CO3 or t-BuONa.

[0063] The present invention also 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.

[0064] It should be noted that the organic material layer of the organic electroluminescent device in this invention can be formed as a single-layer structure or as a multilayer structure with two or more organic material layers.

[0065] In one embodiment of the present invention, the organic electroluminescent device may have a structure comprising an organic material layer including a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting auxiliary layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer. However, the structure of the organic electroluminescent device is not limited to this, and may include fewer or more organic material layers.

[0066] In one embodiment of the present invention, the light-emitting layer includes a host material and a dopant material, wherein the dopant material contains the phosphorescent dopant material described above.

[0067] This invention also provides an application of phosphorescent doped materials in organic electroluminescent devices.

[0068] Furthermore, the organic electroluminescent device can be used in organic electroluminescent apparatuses, including but not limited to flat panel displays, computer monitors, a medical monitor, a television set, billboards, a lamp for internal or external lighting and / or signaling, head-up displays, fully transparent or partially transparent displays, flexible displays, a laser printer, a telephone, a mobile phone, tablets, a photo album, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a microdisplay, a 3D display, a virtual reality or augmented reality display, vehicles, video walls comprising multiple displays tiled together, theater or stadium screens, phototherapy devices, and signs.

[0069] The beneficial effects of this invention are: This invention provides a phosphorescent doped material of an iridium complex, wherein the host ligand consists of a nitrogen-containing phenanthrene ring and a naphthalene ring substituted with a cyano group at a specific position. Compounds conforming to the general formula of this invention have a large oscillator strength. n Excitation level: This molecule can be efficiently excited after absorbing external energy, and before relaxing to the S1 level, it transfers energy to the surrounding T level through intersystem crossing. mThis allows for a sufficient supply of triplet states, ultimately through S... n With T m The "borrowing effect" of the compound participates in the light emission process, thereby achieving superior luminous efficiency characteristics. Furthermore, devices prepared from compounds conforming to the general formula of this invention exhibit excellent overall performance, lower driving voltage, and longer device lifetime. Attached Figure Description

[0070] Figure 1 The 1H NMR spectrum of compound 141 prepared in Application Example 1 of this invention. Detailed Implementation

[0071] 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.

[0072] This invention involves a series of palladium-catalyzed coupling reactions. On one hand, it utilizes the activity order I > Br > Cl > F; on the other hand, it controls the reaction sites by adjusting the reaction conditions. The reactions are then purified using column chromatography or a silica gel funnel to remove byproducts, yielding the target compound. The following general knowledge is referenced: Organometallic Chemistry (6th Edition), Robert H. Crabtree, published by East China University of Science and Technology Press, Shanghai, September 00, 2017, ISBN: 978-7-5628-5111-0, page 388.

[0073] Organic Chemistry and Optoelectronic Materials Experiment Tutorial, Chen Runfeng, Publisher: Southeast University Press, Publication Date: 2019-11-00, ISBN: 9787564184230, Page 174.

[0074] Application Example 1

[0075]

[0076] (1) Under N2 protection, reactants 141-a (1.0 eq, CSA No.: 3030473-07-2), 141-b (1.1 eq, CSA No.: 55058-83-8), Pd(PPh3)4 (0.01 eq), and K2CO3 (2.0 eq) were added to toluene, ethanol, and water (V) respectively. 甲苯 V 乙醇 V 水In a mixed solvent of 3:1:1, the mixture was heated to 80°C and reacted for 6 hours. After cooling to room temperature, water was added, and the solid was filtered after precipitation. The filter cake was dried and purified by column chromatography. The solvent in the filtrate was removed by a rotary evaporator, and the obtained solid was dried to obtain reactant 141-c.

[0077] (2) Under N2 protection, reactant 141-c (1.0 eq), reactant 1-d (1.5 eq, CSA No.: 10043-35-3), Pd(PPh3)4 (0.05 eq) and potassium acetate (2.0 eq) were dissolved in N,N-dimethylformamide, heated to 85°C, and reacted for 8 h. The solvent was removed using a rotary evaporator. The residue was added to dichloromethane, stirred, filtered, and purified by column chromatography to obtain reactant 141-e.

[0078] (3) Under N2 protection, reactant 141-e (1.0 eq), reactant 1-f (1.1 eq, CSA No.: 506-68-3), Pd(PPh3)4 (0.01 eq) and K2CO3 (2.0 eq) were added to toluene, ethanol and water (V) respectively. 甲苯 V 乙醇 V 水 In a mixed solvent of 3:1:1, the mixture was heated to 80°C and reacted for 6 hours. After cooling to room temperature, water was added, and the solid was filtered after precipitation. The filter cake was dried and purified by column chromatography. The solvent in the filtrate was removed by a rotary evaporator, and the obtained solid was dried to obtain 141 g of reactant.

[0079] (4) Under N2 protection, reactant 141-g (1.0 eq) was dissolved in a mixed solution of 2-ethoxyethanol and water (volume ratio 3:1), and the mixture was degassed with nitrogen for 20 minutes. Then IrCl3·4H2O (0.5 eq) was added, and the mixture was refluxed under N2 protection for 20 h. After cooling to room temperature, a precipitate was formed. The precipitate was filtered, washed sequentially with water, anhydrous ethanol, and petroleum ether, and dried under vacuum to obtain intermediate 141-h.

[0080] (5) Under N2 protection, intermediate 141-h (1.0 eq) and reactant 141-i (8.0 eq, CSA No.: 872802-98-7) were added to 2-ethoxyethanol solution, and the mixture was degassed with N2 for 20 minutes. Then anhydrous potassium carbonate (8.0 eq) was added, and the mixture was refluxed for 20 hours under nitrogen protection. The mixture was cooled, filtered, washed with alcohol, and dried. Dichloromethane was used as solvent for neutral alumina column chromatography. The filtrate was concentrated and the solid precipitated to finally obtain compound 141. (Yield: 39%, MS (ESI, m / Z): [M+H]+ = 1090.73).

[0081] The proton NMR spectrum of compound 141 is as follows: Figure 1 As shown.

[0082] Characterization: HPLC purity: >99.8%.

[0083] Elemental analysis: Test values: C, 69.36; H, 4.96; Ir, 17.65; N, 5.16; O, 2.95.

[0084] Device Application Example 1 Fabrication of red-light organic electroluminescent devices: The structure of the fabricated OLED device is: ITO anode / HIL / HTL / Prime / EML / HBL / ETL / EIL / cathode / light extraction layer.

[0085] a. ITO anode: The ITO-Ag-ITO glass substrate with a coating thickness of 150nm was cleaned twice in distilled water and ultrasonically washed for 30min. Then it was cleaned twice more in distilled water and ultrasonically washed for 10min. After washing, it was ultrasonically washed sequentially with methanol, acetone and isopropanol (5min each time). After drying, it was transferred to a plasma cleaner for 5min and then sent to a vapor deposition machine. Using the substrate as the anode, other functional layers were sequentially vapor deposited on it.

[0086] b. HIL (Hole Injection Layer): Hole injection layer materials HT and P-dopant are vacuum-deposited at a deposition rate of 1 Å / s, wherein the deposition rate ratio of HT to P-dopant is 97:3, and the thickness is 10 nm.

[0087] c. HTL (Hole Transport Layer): A 120nm HT layer is vacuum-deposited on top of the hole injection layer at a deposition rate of 1.5 Å / s as the hole transport layer.

[0088] d. Prime (light-emitting auxiliary layer): An 85nm Prime is vacuum-deposited on the hole transport layer as a light-emitting auxiliary layer at a deposition rate of 0.5 Å / s.

[0089] e. EML (Light Emitting Layer): Then, on the above-mentioned light-emitting auxiliary layer, a host material (RH) and a dopant material (compound 141) with a thickness of 40 nm are vacuum-deposited at a deposition rate of 1 Å / s as the light-emitting layer, wherein the deposition rate ratio of RH to compound 141 is 98:2.

[0090] f. HBL (hole blocking layer): A hole blocking layer HB with a thickness of 5 nm is vacuum-deposited at a deposition rate of 0.5 Å / s.

[0091] g. ETL (Electron Transport Layer): ET and Liq were vacuum-deposited at a deposition rate of 1 Å / s to a thickness of 30 nm as the electron transport layer. The deposition rate ratio of compounds ET and Liq was 50:50.

[0092] h. EIL (Electron Injection Layer): A 1 nm Yb film is deposited at a deposition rate of 0.5 Å / s to form an electron injection layer.

[0093] i. Cathode: Magnesium and silver are deposited at a deposition rate of 1 Å / s for 13 nm, with a deposition rate ratio of 1:9, to obtain the OLED device.

[0094] j. Optical extraction layer: A CPL with a thickness of 70 nm is vacuum-deposited on the cathode at a deposition rate of 1 Å / s as the optical extraction layer.

[0095] k. Subsequently, the vapor-deposited substrate is encapsulated. First, the cleaned cover plate is coated with UV adhesive using an adhesive coating equipment. Then, the coated cover plate is moved to the lamination section, and the vapor-deposited substrate is placed on the top of the cover plate. Finally, the substrate and cover plate are laminated under the action of the lamination equipment, while the UV adhesive is cured by light.

[0096] The material structure used in the device application example is as follows:

[0097] Simulation calculation The simulation calculations were performed using the Gaussian16 program. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were performed at the computational levels of B3LYP functionals and mixed basis sets (metal atoms: LANL2DZ type basis set, non-metal atoms: 6-31G(d,p)).

[0098] The chemical structures of comparative compounds 1-6 are shown below. Among them, comparative compounds 1, 2, and 3 correspond to the structures in several UDC patents, such as US20210094978A1 and US11127906B2; comparative compounds 4, 5, and 6 correspond to the structures in several BSS patents, such as US20220109118A1 and US20230144101A1.

[0099]

[0100] At the structural level, comparative compounds 1 and 4 have the same LUMO orbital distribution characteristics as compound 1 in this invention, comparative compounds 2 and 5 have the same LUMO orbital distribution characteristics as compound 2 in this invention, and comparative compounds 3 and 6 have the same LUMO orbital distribution characteristics as compound 64 in this invention.

[0101]

[0102] In this invention, compound 1 has a basic structure relative to compounds 2 and 64, i.e., there are no substituents on the phenanthrene ring, compound 2 has an electron-withdrawing group (EWG) on the phenanthrene ring, and compound 64 has an electron-donating group (EDG) on the phenanthrene ring.

[0103] The table below shows the excitation energy, wavelength, oscillator strength, and S for the corresponding structures S1 to S5 above them. n -T1 energy level difference (S n For the corresponding S1~S5):

[0104]

[0105]

[0106] As can be seen from the table above, compounds 1, 2, and 64 in this invention exhibit greater oscillator strength compared to comparative compounds 1-6.

[0107] Normally, molecules are excited from the ground state S0 to S... n After reaching the S1 state, before intersystem crossing occurs, it rapidly relaxes to the S1 state through internal transition. However, when the molecule contains an S1 state with a large oscillator strength... n When excited to the energy level, the molecule can be efficiently excited after absorbing external energy, and before relaxing to the S1 energy level, it transfers energy to the surrounding T level through intersystem crossing. m The triplet state is thus fully supplied. Compounds 1, 2, and 64 of this application, under the same substitution method as comparative compounds 1-6, have a higher St... n The oscillator strength of the excited energy level is particularly excellent, therefore it can be obtained through S n With T m The "borrowing effect" participates in the light emission process, thereby obtaining better luminous efficiency characteristics.

[0108] Device Application Examples 2-4 Following the preparation method of the above-mentioned device application example 1, organic electroluminescent devices were prepared by replacing compound 141 with compounds 1, 2, and 64, respectively, and are referred to as device application examples 2-4.

[0109] Device Comparison Examples 1-6 Referring to the preparation method of the above-mentioned device application example 1, existing comparative compounds 1-6 were used to replace compound 141 in the above-mentioned device application example 1 for vapor deposition, and are referred to as device comparative examples 1-6.

[0110] The driving voltage and luminous efficiency of the organic electroluminescent devices obtained by the above-mentioned devices in Examples 2-4 and Comparative Examples 1-6 were characterized at a brightness of 6000 nits. The results are shown in Table 1 below.

[0111] Table 1

[0112] Device Application Example 5-195 Referring to the preparation method provided in Device Application Example 1 above, the corresponding compounds in Device Application Examples 5-195 in Table 2 were used to replace compound 141, and the corresponding organic electroluminescent devices were prepared.

[0113] Device Comparison Example 7-30 The preparation method is the same as that in Device Application Example 1, except that the organic electroluminescent device uses existing comparative compound 7-30 instead of compound 141 in Device Application Example 1 for vapor deposition.

[0114] The chemical structural formula of the comparative compound 7-30 is as follows:

[0115]

[0116]

[0117]

[0118]

[0119]

[0120] The driving voltage, luminous efficiency, and lifetime of the organic electroluminescent devices obtained by applying Examples 5-195 and Comparative Examples 7-30 to the above devices were characterized at a brightness of 6000 nits. The results are shown in Table 2 below.

[0121] Table 2

[0122]

[0123]

[0124]

[0125]

[0126]

[0127] As shown in Tables 1 and 2, the OLED devices prepared using the compounds of Formula 1 provided in the application examples of the present invention as red light doping materials (device application examples 1-195) and the OLED devices prepared using the existing materials provided in device comparative examples 1-30, the compounds containing the general formula of the present invention exhibit advantages in terms of low driving voltage, high luminous efficiency and long device lifetime compared to the comparative compounds, and the overall device performance is better.

[0128] The above description of the disclosed applications enables those skilled in the art to make or use the invention. Various modifications to these applications will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other applications without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the applications shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A phosphorescent doped material, characterized in that, The phosphorescent doping material has the chemical formula Ir(L) a )2(L b )1, of which ligand L a It has the general formula structure shown in Formula 1 or Formula 2: ， in, R1 and R3 are each independently selected from hydrogen, deuterium, boron, halogen, cyano, trimethylsilyl, trimethylgermanyl, nitro, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C6-C24 aryl, substituted or unsubstituted C6-C18 heteroaryl, and their heteroatoms contain at least one of O, S, N, Si, Ge, and Se. m and n are each independently selected from 0, 1, 2, 3, 4, 5, 6, 7 or 8. When m and n are greater than 1, multiple R1 and R3 are the same or different from each other. R2 and R4 are each independently selected from boron, halogen, cyano, trimethylsilyl, trimethylgermanyl, nitro, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C6-C24 aryl, substituted or unsubstituted C5-C18 heteroaryl, and their heteroatoms contain at least one of O, S, N, Si, Ge, and Se. ligand L b It has the general formula structure shown in Equation 3: ； R5, R6, and R7 are each independently selected from hydrogen, deuterium, halogen, cyano, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C15 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C6-C18 aryl, and substituted or unsubstituted C6-C18 heteroaryl, wherein their heteroatoms contain at least one of O, S, N, Si, Ge, and Se.

2. The phosphorescent doped material according to claim 1, characterized in that, R1 and R3 are each independently selected from hydrogen, deuterium, halogen, cyano, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C6-C10 heteroaryl, and their heteroatoms contain at least one of O, S, N, Si, Ge, and Se. R2 and R4 are each independently selected from halogens, cyano groups, trimethylsilyl groups, trimethylgermanyl groups, substituted or unsubstituted C1-C6 alkyl groups, substituted or unsubstituted C3-C6 cycloalkyl groups, substituted or unsubstituted C6-C18 aryl groups, and substituted or unsubstituted C6-C10 heteroaryl groups, wherein their heteroatoms contain at least one of O, S, N, Si, Ge, and Se.

3. The phosphorescent doped material according to claim 1, characterized in that, R5, R6, and R7 are each independently selected from hydrogen, deuterium, halogen, cyano, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C7 alkyl, substituted or unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted C6-C12 aryl, substituted or unsubstituted C2-C9 heteroaryl, and their heteroatoms contain at least one of O, S, N, Si, Ge, and Se.

4. The phosphorescent doped material according to claim 1, characterized in that, R1 and R3 are each independently selected from the following structures: ， " "" indicates the binding sites of R1-R4 with carbon on the ring.

5. The phosphorescent doped material according to claim 1, characterized in that, R2 and R4 are each independently selected from the following structures: ， " "" indicates the binding sites of R1-R4 with carbon on the ring.

6. The phosphorescent doped material according to claim 1, characterized in that, Equations 1 and 2 include the following structures: 。 7. The phosphorescent doped material according to claim 1, characterized in that, The term "substituted or unsubstituted" means substituted with one, two or more of the following substituents: deuterium, -CN, -F, -Cl, -Br, C1-C4 alkyl, C3-C6 cycloalkyl, C1-C4 heteroalkyl (the heteroatom in the heterocycloalkyl is selected from O, S, N, Si or Ge) or without substituents.

8. The phosphorescent doped material according to claim 1, characterized in that, The phosphorescent doped material has any one of the following compounds: 。 9. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes an anode, a cathode, and an organic material layer disposed between the anode and the cathode. The organic material layer includes a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting auxiliary layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc., as the structure of the organic material layer. The light-emitting layer includes a host material and a dopant material, and the dopant material contains the phosphorescent dopant material as described in any one of claims 1 to 8.

Images