An organic electroluminescence device, a lighting or display device comprising the same

Abstract

The application relates to the technical field of organic photoelectric material preparation, in particular to an organic electroluminescent device and an illumination or display device containing the same. In the organic electroluminescent device, a compound containing a benzopentaheterocyclic ring fused phenanthryl group as a key group is used for the covering layer, and the hole blocking layer of the limited material can improve the light emission and light extraction efficiency of the device, improve the dependence on the angle, effectively improve the light emission efficiency of the organic electroluminescent device, and has a good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic optoelectronic material preparation, and particularly relates to an organic electroluminescent device and a lighting or display device comprising the same. BACKGROUND

[0002] An organic electroluminescent diode (OLED) is also known as an organic electroluminescent device. The OLED is a technology that converts electrical energy into light energy through organic light-emitting materials by applying a voltage to an organic electroluminescent element, injecting holes from an anode and electrons from a cathode into a light-emitting layer, and recombining the injected holes and electrons to form excitons to cause light emission.

[0003] In recent years, the industry has adopted a top-emitting structure light-emitting element in which a high work function metal is used for the anode and light is emitted from the top, so that the pixel circuit is not blocked and the light-emitting surface can be enlarged. Due to the deviation between the total refractive index of the constituent elements and materials (for example, glass substrate, organic material and electrode material) of the organic light-emitting device and the optimal refractive index depending on the emission wavelength of the organic light-emitting device, part of the light is totally reflected when the emitted light is emitted at a certain angle from the organic layer to the cathode, and only part of the light is utilized. In order to improve the light extraction efficiency and improve the color deviation, a light-emitting element with a high refractive index "cover layer" is usually provided on the outside of the low refractive index semi-transparent electrode to improve the performance of the OLED device. However, the current cover layer material has the problems of low light extraction efficiency, unobvious improvement of device light-emitting efficiency, etc.; resulting in high requirements for the preparation process, large differences in the quality of the obtained device products, and low yield.

[0004] Therefore, it is necessary to develop an organic light-emitting device with good light extraction and improved light-emitting efficiency, and to find a suitable OLED optoelectronic functional material for the OLED device to solve the above problems. SUMMARY

[0005] In order to solve the above technical problems, the present application provides an organic electroluminescent device and a display or lighting device comprising the same. The organic electroluminescent device provided by the present application uses a benzopentaheterocyclic ring and a fused heteroaromatic ring base amine compound as the cover layer, which can maintain high stability in the evaporation preparation process, and cooperates with the hole blocking layer material with a defined structure to make the device have high light-emitting and light extraction efficiency.

[0006] The present application provides an organic electroluminescent device, which is realized by the following technical scheme:

[0007] An organic electroluminescent device comprises:

[0008] a substrate layer;

[0009] a first electrode on the substrate.

[0010] an organic light-emitting functional layer, which is on the first electrode;

[0011] a second electrode, which is on the organic light-emitting functional layer;

[0012] a cover layer, which is on the second electrode;

[0013] the compound of the cover layer is an electron type structure with an electron-withdrawing group, and has a structure of Formula A: ;

[0014] in Formula A, Ar1 is represented by , X is a C or N atom, Y is an O or S atom, any one of R1-R5 is a connecting position with the N atom in Formula A; L, L2, L3 are each independently selected from a single bond or a C6-C30 arylene group;

[0015] Ar2 is selected from , any one of “*1” or “*2” is a connecting position with L2, Z is selected from an O or S atom, and ring H is a substituted or unsubstituted phenanthryl group; the substituted group in the “substituted or unsubstituted” is selected from hydrogen, deuterium, C6-C30 aryl;

[0016] Ar3 is selected from a structure of Formula B or Formula C, and Ar3 can be the same as or different from Ar1 and Ar2;

[0017] the organic light-emitting functional layer further comprises a hole blocking layer, and the hole blocking layer contains a triazine compound of Formula I:

[0018] ;

[0019] in Formula I, Ar5 and Ar6 are each independently selected from a phenyl group, a biphenyl group, L4-L6 are each independently selected from a single bond, a phenyl group, a biphenyl group, a naphthyl group; Ar4 is independently selected from a substituted or unsubstituted triazinyl group, a substituted or unsubstituted diphenylfluorenyl group, a substituted or unsubstituted spirofluorene xanthene group, the “substitution” in the substituted or unsubstituted refers to any one or more of hydrogen, deuterium, C1-C12 alkyl, C6-C30 aryl, and the substitution includes a fused manner; the hydrogen atoms in the structure of Formula I can be partially or completely deuterated.

[0020] Preferably, the compound of Formula A satisfies the following ranges of refractive index n and extinction coefficient K: n @460nm ≥ 2.20, n @530nm ≥ 1.95, n @620nm ≥ 1.88, n @460nm and the difference Δn @620nm between n （n@460nm-n@620nm） ≤ 0.35; the extinction coefficient K@400nm ≤ 1.40, K @430nm ≤ 0.40, K @460nm ≤ 0.05.

[0021] Preferably, Ar3 is selected from the same structure as Ar1.

[0022] Preferably, Ar3 is selected from the same structure as Ar2.

[0023] Preferably, the formula B is selected from any one of B1-B8, and "*" represents the connecting site with the N atom in formula A:

[0024] .

[0025] Preferably, the formula C is selected from the structure shown in C1 or C2, wherein Z is selected from O or S atom, and either "*"1" or "*2" is the connecting site of C1 with L2, and "*3" is the connecting site of C2 with L2:

[0026] .

[0027] More preferably, in the formula A, L2 and L3 are selected from a single bond or a phenyl group.

[0028] According to one or more embodiments, the present application provides an organic electroluminescent device, and the compound of the covering layer is selected from any one of the chemical structures shown below:

[0029]

[0030] Preferably, in the formula I, Ar4 is independently selected from any one of the following structures, and "*" represents the connecting site of Ar4 with L5:

[0031] More preferably, the hole blocking layer is selected from any one or more of the following:

[0032] .

[0033] The organic electroluminescent device of the present application can be used in an OLED lighting or display device.

[0034] The present application also provides a display or lighting device, which comprises one or more of the organic electroluminescent devices as described above.

[0035] The present application also provides a composition comprising a compound of the structure of Formula A:

[0036] ;

[0037] In Formula A, Ar1 is represented by , X is a C or N atom, Y is an O or S atom, any one of R1-R5 is a connecting position to the N atom in Formula A; L, L2, L3 are each independently selected from a single bond or a C6-C30 arylene group;

[0038] Ar2 is selected from , either “*1” or “*2” is a connecting position to L2, Z is selected from an O or S atom, and ring H is a substituted or unsubstituted phenanthryl group; the “substituted” group in the substituted or unsubstituted is selected from hydrogen, deuterium, a C6-C30 aryl group;

[0039] Ar3 is selected from the structure of Formula B or Formula C, and Ar3 can be the same as or different from Ar1 and Ar2; the hydrogen atoms in the structure of Formula A can be partially or completely deuterated;

[0040] The composition further comprises a triazine compound of the structure of Formula I:

[0041] ;

[0042] In Formula I, Ar5 and Ar6 are each independently selected from a phenyl group, a biphenyl group, L4-L6 are each independently selected from a single bond, a phenyl group, a biphenyl group, a naphthyl group; Ar4 is independently selected from a substituted or unsubstituted triazinyl group, a substituted or unsubstituted diphenylfluorenyl group, a substituted or unsubstituted spirofluorene xanthene group, the “substitution” in the substituted or unsubstituted refers to any one or more of hydrogen, deuterium, a C1-C12 alkyl group, a C6-C30 aryl group, a C5-C36 heteroaryl group, and the substitution includes a fused manner; the hydrogen atoms in the structure of Formula I can be partially or completely deuterated.

[0043] In summary, compared with the prior art, the present application has the following beneficial effects:

[0044] In the organic electroluminescent device of the present application, the covering layer is matched by limiting the benzopentaheterocycle-fused phenanthryl group as the core substituent group, and the refractive index and extinction coefficient of the covering layer material are limited, so that the compound has excellent light transmittance and better evaporation stability; the hole blocking layer material is matched with the limited material to be used in the device, which effectively improves the light emitting and light extraction efficiency of the organic light emitting device. DETAILED DESCRIPTION

[0045] The technical solutions of the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0046] The arylene group in the present application refers to a divalent group formed by removing two hydrogen atoms from an aryl group (such as benzene, naphthalene, anthracene, etc.), which can contain monocyclic, fused ring or polycyclic structure, and can have substituents. Common types include phenylene, biphenylene, naphthylene, etc., but are not limited thereto. The aryl group can be an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. The aryl group or aromatic group, as used herein, contemplates non-fused and fused systems. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, pyrene, chrysene, fluorene, pyrene, perylene, and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene, and naphthalene. Examples of non-fused aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p-tolyl, p-(2-phenylpropyl)phenyl, 4'-methylbiphenylyl, 4"-tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesityl, and m-quaterphenyl.

[0047] "Alkyl" means and includes straight-chain and branched alkyl groups. Preferred alkyl groups are alkyl groups containing 1-12 carbon atoms, including methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, and the like. Additionally, the alkyl group can be optionally substituted.

[0048] Throughout this specification, unless expressly stated to the contrary, "comprising" means "comprehending, including, or encompassing, but not limited to, or consisting of, and "comprise, "comprises, "comprised of" or "comprising" when construed as open-ended notation can connote the possibility that zero, some, or all of the elements can be present, and are therefore to be interpreted in the non-limiting manner, even though the term can be used in either a limiting or an open-ended fashion. Throughout this specification, unless explicitly stated otherwise, "comprising" any component will be understood to implicitly include also other elements, rather than excluding any other elements. Also, it is to be understood that throughout this specification, when an element such as a layer, film, region, or substrate is referred to as being "on" or "over" another element, it can be "directly on" the other element, or an intervening element can also be present. In addition, "on" or "over" refers to being positioned above the target portion, without necessarily referring to being positioned above in the direction of gravitational force.

[0049] An object of the present application is to provide an organic electroluminescent device (OLED) comprising: a substrate layer; a first electrode over the substrate; an organic light-emitting functional layer over the first electrode; a second electrode over the organic light-emitting functional layer; a cover layer over the second electrode; the cover layer comprising a defined material of a benzopentaheterocycle-fused phenanthryl group according to Formula A of the present application; and the organic light-emitting functional layer further comprising a hole blocking layer containing a triazine group material according to Formula I.

[0050] In a preferred embodiment of the present application, an OLED is provided, comprising a substrate, an anode, an organic light-emitting functional layer, a cathode, and a cover layer, wherein the organic light-emitting functional layer can comprise a light-emitting layer, a hole transport layer, a hole injection layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc., and can also comprise only a light-emitting layer and one or more other layers; wherein the hole blocking layer comprises a material according to Formula I; and the cover layer comprises one or more components selected from the compounds according to Formula A described above. The cover layer is located on the side of the cathode facing away from the organic light-emitting functional layer. Optionally, there is also a protective layer and / or an encapsulating layer over the cover layer.

[0051] The substrate according to the present application can be any substrate used in typical organic light-emitting devices. It can be a glass or transparent plastic substrate, or a substrate of non-transparent material such as silicon or stainless steel, or a flexible PI film. Different substrates have different mechanical strength, thermal stability, transparency, surface smoothness, and water resistance, and the use direction is different according to the properties of the substrate.

[0052] As the material in the hole injection layer, the hole transport layer, the electron injection layer, the hole transport layer, and the light-emitting layer, any material can be selected from the known related materials for OLED devices.

[0053] The present application will be described in detail below with reference to specific examples. All raw materials and solvents used in the synthesis examples are commercially available unless otherwise specified, and the solvents are used directly without further treatment.

[0054] Preparation Example

[0055] Preparation Example 1

[0056] Synthetic route:

[0057] ;

[0058] Synthetic method:

[0059] (1) Put P0 (33 mmol) into a 250ml three-necked flask, replace with nitrogen for 3 times, add sodium bis(trimethylsilyl)amide (120 mmol), start heating to 80℃ and keep for 2h; the raw material is completely reacted, add 20ml concentrated hydrochloric acid, and the solid is precipitated; filter, and wash the solid with 5ml toluene; add 150ml chlorobenzene solution, adjust pH=10, and add 150ml n-heptane to precipitate the solid; filter, wash, and get the pre-product; dry in a vacuum oven at 100℃ overnight to get the target product P1.

[0060] Preparation Example 2

[0061] Synthetic route:

[0062] ;

[0063] Synthetic method:

[0064] (1) Put SM1 (10mmol), SM2 (10mmol), potassium carbonate (10mmol), N,N-dimethylacetamide (100ml) into a reaction flask, and replace with nitrogen; heat to 120℃, stop heating after 12 hours; cool to room temperature, add 125ml purified water; extract 3 times with dichloromethane (500ml); dry, filter, wash, and concentrate under reduced pressure to get a viscous liquid, add silica gel, and chromatograph by wet method (chromatography conditions: PE:DCM=10:1 elution) to get the product S1;

[0065] (2) Put S1 (10mmol) into a reaction flask, add 110ml tetrahydrofuran, replace with nitrogen, stir, cool to-5℃, add potassium tert-butoxide (20mmol), heat to room temperature and keep for 30min, then cool to 0℃, and drop methoxymethyltriphenylphosphonium chloride / THF solution (125ml); heat to room temperature and react for 3 hours, add 200ml water to quench the reaction; separate, extract, and combine the organic phase; concentrate under reduced pressure to get a viscous liquid, add silica gel, and chromatograph by wet method (chromatography conditions: PE:DCM=20:1 elution) to get S2;

[0066] (3) Into the reaction bottle, S2 (10 mmol), dichloromethane 500 ml, nitrogen replacement 3 times; drop methyl sulfonic acid (20 mmol): control the temperature below 30℃; incubation reaction 3h, add deionized water 250 ml quenching, adjust Ph to neutral, static stratification, separation to obtain organic phase; reduced pressure concentration to obtain viscous liquid, add silica gel sample, wet column chromatography (chromatography conditions: PE: DCM = 10: 1 elution) to obtain product S3;

[0067] (4) Under nitrogen protection, into the reaction bottle S3 (10 mmol), N, N- dimethylacetamide (600 ml), cesium pivalate (25 mmol), nitrogen replacement; after nitrogen protection, add double (2-phenyl) phosphine phenyl ether 1.8 mmol, double acetonitrile palladium dichloride: 0.8 mmol; heating to 130℃, incubation reaction 2h after stopping heating; reduce to room temperature, precipitate solid, suction filtration, washing, 80℃ vacuum drying 3h, product S4;

[0068] (5) Into the 250ml three-necked bottle, add S4 (33 mmol), 150mL toluene, nitrogen replacement 3 times, add double (trimethylsilyl) sodium amine (120 mmol), start heating to 80℃ incubation reaction 2h; the raw material reaction is complete, add 20mL concentrated hydrochloric acid, precipitate solid; suction filtration, solid with 5mL toluene washing; add 150mL chlorobenzene solution, adjust pH = 10, add 150ml n-heptane precipitate solid; suction filtration, washing, to obtain the pre-product; 100℃ vacuum oven drying overnight, to obtain the target product S5.

[0069] Example

[0070] Example 1: synthesis of compound 19

[0071] ;

[0072] (1) Into the reaction bottle, P1 (10 mmol), P2 (25 mmol), sodium tert-butoxide (10 mmol), toluene 200ml, nitrogen replacement, add pd2 (dba) 3 (5x10 -2 mmol), Sphos (5x10 -2 mmol), heating to 100-120℃, reflux reaction 6 hours, stop reaction. Cooling to 30-40℃, add water 200ml, stratification. After washing twice, concentrated toluene, add n-heptane 100ml, slurry. To obtain the target product-compound 19;

[0073] By liquid chromatography-mass spectrometry analysis, LC-MS (m / z): the theoretical value is 669.21, the test value is 669.67.

[0074] Example 2: Synthesis of Compound 1

[0075] Following the synthesis steps and reaction conditions of Example 1, compound 1 was synthesized, the difference being that reactant P2 was adjusted to... The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 667.21, while the measured value was 667.69.

[0076] Example 3: Synthesis of Compound 6

[0077] Following the synthesis steps and reaction conditions of Example 1, compound 6 was synthesized. The difference from Example 1 is that reactant P1 was changed to... The reactant P2 is changed to The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 715.15, while the measured value was 715.61.

[0078] Example 4: Synthesis of Compound 12

[0079] Synthesis route:

[0080] ;

[0081] Synthesis method:

[0082] (1) Synthesis of P0-1 to obtain P1-1: Refer to the synthesis steps and reaction conditions of P0 to obtain P1 in Preparation Example 1;

[0083] (2) Add P1-1 (10 mmol), P2 (10 mmol), sodium tert-butoxide (10 mmol), and 200 ml of toluene to the reaction flask. After purging with nitrogen, add pd2(dba)3 (5 × 10⁻⁶ mmol). -2 mmol), Sphos (5×10 -2 The mixture was heated to 100-120℃ and refluxed for 6 hours, then the reaction was stopped. The mixture was cooled to 30-40℃, and 200 ml of water was added, resulting in separation of the layers. After washing twice with water, the toluene was concentrated, and 100 ml of n-heptane was added, followed by slurry mixing. The target product, compound P3-1, was obtained.

[0084] (3) Add P3-1 (10 mmol), P4 (10 mmol), sodium tert-butoxide (10 mmol), and 200 ml of toluene to the reaction flask. After purging with nitrogen, add Pd2(dba)3 (5 × 10⁻⁶ mmol). -2 mmol), Sphos (5×10 -2The toluene was heated to 100-120℃ and refluxed for 6 hours, then the reaction was stopped. The mixture was cooled to 30-40℃, 200 ml of water was added, and the layers separated. After washing twice with water, the toluene was concentrated, and 100 ml of n-heptane was added, followed by stirring. The target product, compound 12, was obtained.

[0085] Analysis by liquid chromatography-mass spectrometry yielded the following LC-MS (m / z) values: theoretical value 668.21, measured value 668.65.

[0086] Example 5: Synthesis of Compound 14

[0087] Compound 14 was synthesized following the same synthesis steps and reaction conditions as in Example 4, but differed from that in Example 4 in the following ways:

[0088] ;

[0089] The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 716.14, while the measured value was 716.88.

[0090] Example 6: Synthesis of Compound 23

[0091] Following the synthesis steps and reaction conditions of Example 1, compound 23 was synthesized. The difference from Example 1 is that reactant P1 was changed to... The reactant P2 changes to The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 717.14, while the measured value was 717.84.

[0092] Example 7: Synthesis of Compound 25

[0093] Referring to the synthesis steps and reaction conditions of Example 1, compound 25 was synthesized. The difference from Example 1 is that in the synthesis step (1), the amount of P1 added to the reaction flask was 25 mmol and the amount of P2 added was 10 mmol. The product was analyzed by liquid chromatography-mass spectrometry and the LC-MS (m / z) results were: theoretical value 742.23, test value 742.75.

[0094] Example 8: Synthesis of Compound 28

[0095] Following the synthesis steps and reaction conditions of Example 1, compound 28 was synthesized. The difference from Example 1 is that reactant P2 was changed to... The reactant P1 is changed to The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 745.24, while the measured value was 745.78.

[0096] Example 9: Synthesis of Compound 37

[0097] Following the synthesis steps and reaction conditions of Example 1, compound 37 was synthesized. The difference from Example 1 is that reactant P2 was changed to... The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 667.21, while the measured value was 667.69.

[0098] Example 10: Synthesis of Compound 49

[0099] Following the synthesis steps and reaction conditions of Example 4, compound 49 was synthesized, differing from that of Example 4 in that...

[0100] ;

[0101] The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 668.21, while the measured value was 668.67.

[0102] Example 11: Synthesis of Compound 31

[0103] Following the synthesis steps and reaction conditions of Example 10, compound 31 was synthesized. The difference from Example 10 is that reactant P2-1 was changed to... The reactant P4 was changed to The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 699.17, while the measured value was 699.65.

[0104] Example 12: Synthesis of Compound 52

[0105] Following the synthesis steps and reaction conditions of Example 1, compound 52 was synthesized. The difference from Example 10 is that reactant P2-1 was changed to... The reactant P4 was changed to The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 700.16, while the measured value was 700.78.

[0106] Example 13: Synthesis of Compound 59

[0107] Following the synthesis steps and reaction conditions of Example 4, compound 59 was synthesized. The difference from Example 4 is that the reactant P0-1 was changed to... The reactant P2 is changed to The reactant P4 was changed to The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 716.14, while the measured value was 716.82.

[0108] Example 14: Synthesis of Compound 66

[0109] Following the synthesis steps and reaction conditions of Example 1, compound 66 was synthesized. The difference from Example 1 is that reactant P1 was changed to... The product was analyzed by liquid chromatography-mass spectrometry (LC-MS) and the theoretical value was 745.24, while the measured value was 745.80.

[0110] The following are several examples of applications of the capping layer compounds described in this invention in OLED devices to further illustrate the beneficial effects of the compounds of this invention. The materials used in the examples were either commercially available or synthesized in-house.

[0111] Manufacturing of OLED devices:

[0112] As a reference fabrication method for one embodiment of the device, the present invention involves depositing a 50-500 nm ITO / Ag / ITO (ITO:Ag:ITO weight ratio = 1:(10-20):1) layer on an alkali-free glass substrate as the anode. Then, a hole injection layer (5 nm-20 nm), a hole transport layer (50-150 nm), a light-emitting auxiliary layer (5-120 nm), a light-emitting layer (20-50 nm), a hole blocking layer (5-20 nm), an electron transport layer (20-80 nm), and an electron injection layer (1-10 nm) are deposited on the anode. Following this, Mg and Ag (weight ratio 1:9, 10-15 nm) are co-deposited to form a semi-transparent cathode, and then a capping compound (30 nm-90 nm) is deposited. Finally, the light-emitting device is encapsulated using epoxy resin adhesive under a nitrogen atmosphere.

[0113] In a preferred embodiment, the OLED device provided by the present invention has the following structure: first, an alkali-free glass substrate is washed with isopropanol for 15 minutes using an ultrasonic cleaner, and then subjected to UV ozone washing treatment in the air for 30 minutes. The prepared substrate was deposited using vacuum evaporation. ITO / Ag / ITO (ITO:Ag:ITO weight ratio = 1:10:1, 120nm) was deposited as the anode. Then, a hole injection layer (HT:PD, 10nm, 2%), a hole transport layer (HT, 130nm), a light-emitting auxiliary layer (BP, 5nm), a blue light-emitting layer (body material: dopant material = BH:BD (weight ratio 98:2, 30nm)), a hole blocking layer (HB6, 5nm), an electron transport layer (ET:Liq = 1:1, 30nm), and an electron injection layer (Yb, 1nm) were sequentially deposited. Mg and Ag (weight ratio 1:9, 13nm) were then co-deposited to form a semi-transparent cathode. Finally, compound 19 of this invention (65nm) was deposited as a capping layer. The light-emitting device was then encapsulated using epoxy resin adhesive under a nitrogen atmosphere, as described in Application Example 1. The molecular structural formulas of the relevant materials are shown below (particularly preferably selected from the following structures, but this does not mean that the invention is limited to the following structures):

[0114]

[0115] Application Examples 2-16 and Comparative Examples 1-3 were prepared using the method described in Application Example 1 above, with the only difference being that compounds listed in Table 2 were used as luminescent auxiliary materials to replace compound 19 in Application Example 1 or to replace compound HB6 used in the hole-blocking layer of Application Example 1. The structures of Ref-CP and Ref-HB used in Comparative Examples 1-3 are as follows:

[0116] .

[0117] Performance evaluation of OLED devices:

[0118] Performance Test 1: Material Refractive Index Characterization

[0119] To measure the optical properties of the compounds, the refractive index (n) of the compounds prepared in Examples 1-14 of this invention was measured at different wavelengths using an ellipsometer. Glass substrates (0.7T) were cleaned in ethanol, deionized water, and acetone for later use. A monolayer film of the compound of this invention with a thickness of 80 nm was deposited on the cleaned glass substrate. The refractive index (n) of the prepared monolayer film was measured at different wavelengths using an ellipsometer, and these values ​​were used as initial parameters for modeling and fitting using the Cauchy formula. Simultaneously, adaptation and correction were performed using the B-spline model, GEN-OSC model, and Biaxial model to obtain representative n (refractive index) and K (extinction coefficient) test values ​​for the compounds at different wavelengths. The comparative compound Ref-CP was used as a control example 1, and its structure is recorded in Table 1. The structure of Ref-CP is as follows: .

[0120] Table 1. Represents the refractive index (n) and extinction coefficient (K) of compounds at different wavelengths.

[0121]

[0122] As can be seen from the data in Table 1, compared with Comparative Example 1, the compounds prepared in Examples 1-14 of the present invention have a significant increase in refractive index in each wavelength region (RGB wavelength), and the absorption changes at 400nm and 430nm are not significant. This indicates that the capping material of this application can better improve the optical coupling efficiency of the device in the three colors of RGB.

[0123] Performance Test 2: Characterization of Device Luminescence Performance

[0124] The current of the OLED device at different voltages was measured using a Keithley 2365A digital nanovoltmeter, and then the current density of the OLED device at different voltages was obtained by dividing the current by the emitting area. The brightness and radiant energy flux density of the OLED device at different voltages were measured using a Konicaminolta CS-2000 spectroradiometer. Based on the current density and brightness of the OLED device at different voltages, the current density (10 mA / cm²) at the same voltage was obtained. 2 The operating voltage (Volt) and current efficiency (cd / A) are given by BI = E / CIEy, which refers to the Blue Index in blue light and is also a parameter measuring the luminous efficiency of blue light. E refers to the current efficiency, and CIEy refers to the ordinate color point obtained by substituting the wavelength of the device's emission half-peak into the CIE1930 software. The test data are shown in Table 2.

[0125] Table 2. Examples of Applications of Composite Materials and Their Electroluminescence Properties

[0126]

[0127] As shown in Table 2, compared with Comparative Examples 1-3, Application Examples 1 to 16 exhibit higher blue light BI luminous efficiency. The performance improvement in each application example is based on the significant increase in the refractive index n value of the capping layer material used in this invention, and the controllable absorption at 400, 430, and 460 nm. The compound material used in the capping layer of this invention has better film-forming stability and a higher refractive index. Combined with the defined hole-blocking layer material, its application in devices can improve luminescence and light extraction efficiency while reducing device power consumption.

[0128] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. An organic electroluminescent device, characterized in that, include: Substrate layer; A first electrode is located on the substrate; An organic light-emitting functional layer is disposed on the first electrode; The second electrode is located on the organic light-emitting functional layer; A capping layer is placed over the second electrode; The compound of the capping layer has an electronic structure with electron-withdrawing groups and has the structure of formula A: ; In formula A, Ar1 is derived from... This indicates that X is a C or N atom, Y is an O or S atom, and any one of R1-R5 serves as a connection site with the N atom in formula A; L, L2, and L3 are each independently selected from single bonds or C6-C30 arylene groups. Ar2 is selected from Either "*1" or "*2" serves as the connection site with L2, Z is selected from O or S atoms, and the ring H is a substituted or unsubstituted phenanthrene group; the substituted group in "substituted or unsubstituted" is selected from hydrogen, deuterium, and C6-C30 aryl. Ar3 is selected from either structure B or structure C, and Ar3 may be the same as or different from either Ar1 or Ar2. The organic light-emitting functional layer further includes a hole-blocking layer, which contains a triazine compound of formula I: ； In Formula I, Ar5 and Ar6 are each independently selected from phenyl and biphenyl, and L4-L6 are each independently selected from single bond, phenyl, biphenyl, and naphthyl; Ar4 is independently selected from substituted or unsubstituted triazine, substituted or unsubstituted diphenylfluorenyl, and substituted or unsubstituted spirofluorenoxanthyl. The "substituted" in the context of substitution or unsubstituted refers to any one or more of hydrogen, deuterium, C1-C12 alkyl, and C6-C30 aryl, and the substitution includes fusion. The hydrogen atoms in the structure of Formula I may be partially or completely deuterated.

2. The organic electroluminescent device according to claim 1, characterized in that, The compound of formula A satisfies the following ranges for refractive index n and extinction coefficient K: n @460nm ≥2.20, n @530nm ≥1.95, n @620nm ≥1.88, n @460nm With n @620nm Difference △n （n@460nm-n@620nm） ≤0.35; Extinction coefficient K @400nm ≤1.40, K @430nm ≤0.40, K @460nm ≤0.

05.

3. The organic electroluminescent device according to claim 1, characterized in that, Formula B is selected from any structure from B1 to B8, and "*" indicates the connection site with the N atom in formula A: 。 4. The organic electroluminescent device according to claim 1, characterized in that, The formula C is selected from the structure shown in C1 or C2, where Z is selected from O or S atoms, either "*1" or "*2" serves as the connection point between C1 and L2, and "*3" serves as the connection point between C2 and L2. 。 5. The organic electroluminescent device according to claim 1, characterized in that, The capping compound is selected from any one of the following chemical structures: 。 6. The organic electroluminescent device according to claim 1, characterized in that, In Formula I, Ar4 is independently selected from any of the following structures, where * represents the connection site between Ar4 and L5: 。 7. The organic electroluminescent device according to claim 1, characterized in that, The hole-blocking layer is selected from any one or more of the following: 。 8. The use of the organic electroluminescent device according to any one of claims 1-7 in a display or lighting device.

9. A display or lighting device, characterized in that, The device comprises an organic electroluminescent device as described in any one of claims 1-7.

10. A composition, characterized in that, The composition comprises compounds of formula A: ； In formula A, Ar1 is derived from... This indicates that X is a C or N atom, Y is an O or S atom, and any one of R1-R5 serves as a connection site with the N atom in formula A; L, L2, and L3 are each independently selected from single bonds or C6-C30 arylene groups. Ar2 is selected from Either "*1" or "*2" serves as the connection site with L2, Z is selected from O or S atoms, and the ring H is a substituted or unsubstituted phenanthrene group; the substituted group in "substituted or unsubstituted" is selected from hydrogen, deuterium, and C6-C30 aryl. Ar3 is selected from either structure B or structure C, and Ar3 may be the same as or different from either Ar1 or Ar2; the hydrogen atoms in structure A may be partially or completely deuterated. The composition also includes a triazine compound of formula I: ； In Formula I, Ar5 and Ar6 are each independently selected from phenyl and biphenyl, and L4-L6 are each independently selected from single bond, phenyl, biphenyl, and naphthyl; Ar4 is independently selected from substituted or unsubstituted triazine, substituted or unsubstituted diphenylfluorenyl, and substituted or unsubstituted spirofluorenoxanthyl. The "substituted" in the context of substitution or unsubstituted refers to any one or more of hydrogen, deuterium, C1-C12 alkyl, C6-C30 aryl, and C5-C36 heteroaryl. The substitution includes fusion. The hydrogen atoms in the structure of Formula I may be partially or completely deuterated.

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