Composite material and light emitting device

Abstract

The invention provides a composite material and a light-emitting device. The composite material comprises a heat exciton material and a fluorescent material. The composite material provided by the invention can realize simultaneous utilization of singlet and triplet excitons, so that the utilization efficiency of exciton energy is improved, the recombination efficiency of current carriers is improved, the non-radiation attenuation process is reduced, and the luminous efficiency, brightness and the like are improved.

Description

Technical Field

[0001] This application relates to the field of organic materials technology, and in particular to a composite material and a light-emitting device. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are an important planar light source technology with advantages such as low power consumption, high brightness, wide color gamut, and flexible display. First-generation OLED luminescent materials use ordinary fluorescent materials, with an exciton utilization rate of only 25%. In the luminescent layer, after carrier recombination to form excitons, 25% are singlet excitons, while 75% are triplet excitons. The triplet excitons cannot directly emit light and are wasted. To improve exciton utilization, researchers such as Ma Yuguang proposed second-generation OLED luminescent materials. Utilizing heavy metals to enhance spin-orbit coupling, this material can emit phosphorescence at room temperature and can convert singlet excitons into triplet excitons. The exciton utilization rate of this material can reach 100%. Subsequently, thermally activated delayed fluorescence (TADF) materials and thermal exciton materials proposed by Professor Ma Yuguang were proposed, which can convert triplet excitons into singlet excitons, further improving exciton utilization. Theoretically, the exciton utilization rate of this third-generation OLED luminescent material can also reach 100%.

[0003] For ordinary first-generation fluorescent materials, only 25% of excitons can be used for luminescence, while the energy of the other 75% of excitons is wasted, resulting in low exciton utilization and serious energy waste. Summary of the Invention

[0004] Therefore, in order to improve the exciton utilization rate in fluorescent materials, it is necessary to provide a composite material and a light-emitting device.

[0005] This application provides a composite material, including a thermal exciton material and a fluorescent material;

[0006] The thermal exciton material includes one or more compounds having the following general formula: , , ;

[0007] Among them, R1, R2, R6, and R7 are each independently selected from H, D, halogen, cyano, amino, nitro, and C. 1-20 Alkyl, C 1-20 Alkoxy groups, heteroaryl groups with 5-20 ring atoms, and C 6-20 A combination of one or more aryl groups;

[0008] R3, R4, R5, R8, and R9 are each independently selected from substituted or unsubstituted C. 6-60a combination of one or more of substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl having 5 to 60 ring atoms, substituted or unsubstituted arylamino having 6 to 60 ring atoms, substituted or unsubstituted aryloxy having 6 to 60 ring atoms, substituted or unsubstituted arylthiol having 6 to 60 ring atoms, substituted or unsubstituted heteroarylamino having 5 to 60 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 60 ring atoms, and substituted or unsubstituted heteroarylthiol having 5 to 60 ring atoms;

[0009] each of the substituents of the substituted R3, R4, R5, R8, and R9, independently at each occurrence, is selected from a combination of one or more of D, halogen, cyano, amino, nitro, thiol, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20 alkoxy, heteroaryl having 5 to 30 ring atoms, and substituted or unsubstituted C 6-30 aryl;

[0010] each of the heteroatoms in the heteroaryl, the heteroaryloxy, the heteroarylamino, and the heteroarylthiol is independently selected from one or more of O, P, N, and S.

[0011] In one embodiment, the hot exciton material includes one or more of the following compounds having the general formula:

[0012] , , ;

[0013] wherein R 11 and R 13 are each independently selected from a combination of one or more of C 6-30 aryl;

[0014] each of R5, R8, R 10 , R 12 , and R 14 is independently selected from a combination of one or more of C 1-20 alkyl and one of the following structures: , , ;

[0015] wherein R 15 to R 19 are each independently selected from H, D, halogen, cyano, amino, nitro, substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 1-30 alkoxy, substituted or unsubstituted C 1-30 alkylthiol, substituted or unsubstituted C 1-30alkyl, substituted or unsubstituted C 6-30 aryl having 5 to 20 ring atoms, and a combination of one or more of the foregoing;

[0016] Z is a single bond, -CO-, -N-, -CR 20 R 21 -, -NR 21 -, phenyl, -O-, or -S-;

[0017] R 20 and R 21 are each independently selected from the group consisting of H, D, halogen, cyano, amino, nitro, substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 1-30 alkenyl, substituted or unsubstituted C 1-30 alkoxy, substituted or unsubstituted C 1-30 alkylthiol, substituted or unsubstituted C 1-30 aryl having 5 to 20 ring atoms, and a combination of one or more of the foregoing;

[0018] R 15 ~R 21 substituents described in the above-mentioned substituents, are each independently selected at each occurrence from the group consisting of D, amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid group, thiol, cyano, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20 alkoxy, heteroaryl having 5 to 20 ring atoms, and a combination of one or more of the foregoing; 6-20 aryl having 5 to 20 ring atoms, and a combination of one or more of the foregoing;

[0019] the heteroaryl is selected from one or more of O, P, N, S, and * is a bonding site.

[0020] In one embodiment, R5, R8, R 10 , R 12 , and R 14 are each independently selected from the group consisting of H, C 1-5 alkyl, and one of the following groups:

[0021] ;

[0022] wherein R 22 ~R 35 are each independently selected from the group consisting of H, D, halogen, cyano, amino, nitro, C1-20 alkyl, C 1-20 alkoxy, heteroaryl having 5 to 20 ring atoms, and aryl having 6 to 20 ring atoms; 6-20 one or more of alkyl, C

[0023] and / or, R 11 and R 13 are each independently selected from one of the following groups:

[0024]

[0025] .

[0026] In one embodiment, the hot exciton material includes at least one of the following materials:

[0027] , , , , , , , , , , and .

[0028] In one embodiment, the composite material further includes a sensitizer; wherein the sensitizer includes one or more of the following compounds having the general formula: , ;

[0029] wherein D is a donor group, A is an acceptor group, and L is a linking group;

[0030] the donor group is selected from one or more of a combination of carbazolyl, arylamino, alkylamino, silyl, alkoxy, aryloxy, thio, alkylthio, arylthio, acridinyl, phenoxazinyl, and thioxanthinyl groups;

[0031] said linking group is selected from the group consisting of a single bond, -0-, cycloalkylene, arylene, heteroarylene, heterocycloalkylene, heterocycloalkenylene, in combination of one or more;

[0032] said acceptor group is selected from the group consisting of fluorine, cyano, triazinyl, cyanophenyl, phosphinoyl, ketone carbonyl, sulfone, pyrrolyl, thienyl, pyrazolyl, thiazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, phenazinylene, in combination of one or more;

[0033] m and n are each independently an integer from 1 to 5;

[0034] ring C, ring E, ring F, ring G, and ring H are each independently selected from the group consisting of substituted or unsubstituted C 6-20 aryl, substituted or unsubstituted heteroaryl having 5 to 20 ring atoms, substituted or unsubstituted arylamino having 6 to 20 ring atoms, substituted or unsubstituted aryloxy having 6 to 20 ring atoms, substituted or unsubstituted arylmercapto having 6 to 20 ring atoms, substituted or unsubstituted heteroarylamino having 5 to 20 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 20 ring atoms, substituted or unsubstituted heteroarylmercapto having 5 to 20 ring atoms, in combination of one or more;

[0035] said substituents in ring C, ring E, ring F, ring G, and ring H, at each occurrence, are each independently selected from the group consisting of D, amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid, mercapto, cyano, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20 alkoxy, heteroaryl having 5 to 20 ring atoms, and C 6-20 aryl, in combination of one or more;

[0036] the heteroatoms in said heterocycloalkylene, said heterocycloalkenylene, said heteroaryl, said heteroaryloxy, said heteroarylamino, and said heteroarylmercapto are each independently selected from the group consisting of one or more of O, P, N, S.

[0037] In one embodiment, said donor group is selected from the group consisting of and in combination of one or both;

[0038] said acceptor group comprises and cyano, in combination of one or both;

[0039] R 36 ~R 41 are each independently selected from the group consisting of D, halogen, cyano, amino, nitro, mercapto, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20Alkoxy groups, heteroaryl groups with 5-30 ring atoms, and C 6-30 One or more combinations of aryl groups; the heteroatom in the heteroaryl group is selected from one or more of O, P, N, and S;

[0040] And / or, rings C, E, F, G, and H are each independently selected from substituted or unsubstituted C. 6-20 Aryl;

[0041] The substituents described in rings C, E, F, G, and H, each time appearing, are independently selected from D, amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid, mercapto, cyano, carbonyl, C 1-20 Alkyl, C 1-20 alkenyl, C 1-20 Alkoxy groups, heteroaryl groups with 5-20 ring atoms, and C 6-20 One or more of the aryl groups; the heteroaryl group is selected from one or more of O, P, N, and S.

[0042] In one embodiment, the sensitizer comprises at least one of the following materials: , , , , as well as .

[0043] In one embodiment, the peak wavelength in the absorption spectrum of the fluorescent material is between 250 nm and 500 nm;

[0044] And / or, by mass percentage, the composite material comprises 75% to 97% of the thermal exciton material, 2% to 23% of the sensitizer, and 0.01% to 5% of the fluorescent material;

[0045] And / or, the fluorescent material includes at least one of 8-hydroxyquinoline aluminum and 5,6,11,12-tetraphenyltetraphenyl.

[0046] This application also provides a light-emitting device, including:

[0047] An anode and a cathode are arranged opposite to each other, and a light-emitting layer is disposed between the anode and the cathode;

[0048] The material of the light-emitting layer includes the composite material described above; or, the light-emitting layer is formed from the composite material described above.

[0049] In one of the embodiments, the light-emitting device further comprises a hole functional layer and an electron functional layer, the hole functional layer is located between the anode and the light-emitting layer, and the electron functional layer is located between the light-emitting layer and the cathode;

[0050] The hole functional layer comprises a hole transport layer and / or a hole injection layer arranged in a stack, when both the hole transport layer and the hole injection layer are included, the hole transport layer is arranged closer to the light-emitting layer than the hole injection layer;

[0051] Optionally, the material of the hole transport layer comprises one or more of poly[(9,9-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine)], poly(9-vinylcarbazole), 4,4'-bis(9-carbazolyl)-2,2'-dimethyl-diphenyl, 4,4'-bis(N-carbazolyl)-1,1'-biphenyl, 4,4'-di(9-carbazolyl) biphenyl, P-type phthalocyanine, copper phthalocyanine, 1,3-bis(carbazol-9-yl)benzene, and 4,4',4''-tris(carbazol-9-yl)triphenylamine;

[0052] Optionally, the material of the hole injection layer is selected from one or more of poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate, polyarylamine, N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, 4,4',4"-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane, 4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine], 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane-doped N,N'-diphenyl-N,N'-di(1-naphthyl)-1,1'-biphenyl-4,4''-diamine, poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate, 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, transition metal oxide selected from one or more of NiO, MoO2, MoO3, WO3, and CuO, and transition metal chalcogenide selected from one or more of MoS2, MoSe2, WS3, WSe3, and CuS;

[0053] And / or, the electron functional layer comprises an electron transport layer and / or an electron injection layer arranged in a stack, when both the electron transport layer and the electron injection layer are included, the electron transport layer is arranged closer to the light-emitting layer than the electron injection layer;

[0054] Optionally, the material of the electron transport layer is selected from one or more of 8-hydroxyquinoline aluminum, diphenyl[4-(triphenylsilyl)phenyl]phosphine oxide, 1,3,5-tris(m-pyridin-3-ylphenyl)benzene, 2-(4'-tert-butylphenyl)-5-(4'-biphenyl)-1,3,4-oxadiazole, beryllium octahydrate quinoline, 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole, 2,7-bis(diphenylphosphine oxide)-9,9'-spirobi[fluorene], 3,5-tris(N-phenyl-2-benzimidazole)benzene, 4,6-bis(3,5-di(2-pyridyl)phenyl)-2-methylpyrimidine, and 4,7-diphenyl-1,10-phenanthroline;

[0055] Optionally, the material of the electron injection layer comprises one or more of LiF, Liq, NaF, and CsF.

[0056] Optionally, the material of the anode and the cathode is independently selected from one or both of a metal and a metal oxide, the metal comprising one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg, and the metal oxide comprising a doped or undoped metal oxide comprising one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, and AMO, or a composite electrode comprising a doped or undoped transparent metal oxide sandwiched between a metal, the composite electrode comprising one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2.

[0057] The present application provides a composite material that can achieve simultaneous utilization of singlet and triplet excitons, thereby improving the utilization efficiency of exciton energy and improving the recombination efficiency of carriers, reducing non-radiative decay processes, thereby increasing the luminous efficiency and brightness, etc. BRIEF DESCRIPTION OF DRAWINGS

[0058] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the description of the specific embodiments or the prior art. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0059] Figure 1 A light-emitting device is provided for an embodiment of the present application;

[0060] Figure 2 The current efficiency-current density diagrams of the light emitting devices are provided for the examples and comparative examples of the present application.

[0061] Explanation of Reference Numerals:

[0062] 10: light emitting device; 110: anode; 120: hole injection layer; 130: hole transport layer; 140: light emitting layer; 150: electron transport layer; 160: cathode. DETAILED DESCRIPTION

[0063] In order to make the above objectives, features and advantages of the present application more clear and easily understood, the specific embodiments of the present application will be described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order not to unnecessarily obscure the present application. The purpose of the above summary is to enable the specific embodiments of the present application to be understood, and is not intended to limit the scope of the present application.

[0064] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0065] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0066] In addition, the terms "first", "second", etc. are used only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can include at least one of the features, explicitly or implicitly. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0067] In the present application, "substituted or unsubstituted" means that the defined group can be substituted or unsubstituted. It is understood that when the group is substituted, the number of substituents can be one, two, three or more, and when the number of substituents is two or more, each substituent can be the same or different.

[0068] In the present application, "ring atom number" means the number of atoms constituting a ring itself in a structural compound (e.g., a monocyclic compound or a polycyclic compound) obtained by bonding atoms into a ring, i.e., the number of atoms forming a ring. When the ring is substituted with a substituent, the atoms included in the substituent are not included in the ring atoms. The same applies to "ring atom number" described below, unless otherwise specified. For example, the ring atom number of a benzene ring is 6, the ring atom number of a naphthalene ring is 10, and the ring atom number of a thiophene group is 5.

[0069] In the present application, "aryl group or aromatic group" means an aromatic hydrocarbon group derived by removing one hydrogen atom from an aromatic ring compound, and can be a monocyclic aryl group, or a fused ring aryl group, or a polycyclic aryl group, and at least one of the rings is an aromatic ring system. For example, "substituted or unsubstituted aryl group having 6 to 40 ring atoms" means an aryl group having 6 to 40 ring atoms, and the aryl group can be further optionally substituted. Preferred is a substituted or unsubstituted aryl group having 6 to 30 ring atoms, more preferred is a substituted or unsubstituted aryl group having 6 to 18 ring atoms, particularly preferred is a substituted or unsubstituted aryl group having 6 to 14 ring atoms, and the aryl group is optionally further substituted; suitable examples include, but are not limited to, phenyl, biphenyl, terphenyl, naphthyl, anthryl, phenanthryl, fluoranthenyl, pyrenyl, chrysenyl, tetracenyl, fluorenyl, perylenyl, acenaphthenyl, acenaphthyl, and derivatives thereof. It is understood that a plurality of aryl groups can also be interrupted by short non-aromatic units (e.g., <10% non-H atoms such as C, N, or O atoms), specifically such as acenaphthene, fluorene, or 9,9-diaromatic fluorene, triarylamine, diaryl ether systems should also be included in the definition of aryl group.

[0070] In the present application, "heteroaryl or heteroaromatic group" means that at least one carbon atom of an aryl group is replaced by a non-carbon atom, which can be an N atom, an O atom, an S atom, a Si atom, a P atom, etc. For example, "substituted or unsubstituted heteroaryl group having 5 to 60 ring atoms" means a heteroaryl group having 5 to 60 ring atoms, preferably a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, more preferably a substituted or unsubstituted heteroaryl group having 5 to 18 ring atoms, particularly preferably a substituted or unsubstituted heteroaryl group having 5 to 14 ring atoms, and the heteroaryl group is optionally further substituted; suitable examples include, but are not limited to, thienyl, furanyl, pyrrolyl, dioxazolyl, triazolyl, imidazolyl, pyridyl, bipyridyl, pyrimidyl, triazinyl, acridinyl, pyridazinyl, pyrazinyl, quinolyl, isoquinolyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridopyrimidyl, pyridopyrazinyl, benzothienyl, benzofuranyl, indolyl, pyrroloimidazolyl, pyrrolopyrrolyl, thienopyrrolyl, thienothienyl, furanopyrrolyl, furanofuranyl, thienofuranyl, benzisoxazolyl, benzisothiazolyl, benzimidazolyl, perylenyl, phenanthridinyl, berberinyl, quinazolinonyl, dibenzothienyl, dibenzofuranyl, carbazolyl, and derivatives thereof.

[0071] In the present application, "alkyl" can mean straight chain, branched chain, and / or cyclic alkyl. The number of carbons of the alkyl group can be 1 to 30, 1 to 25, 1 to 20, 1 to 15, 1 to 10, or 1 to 6. The phrase including this term, for example, "C1-C6 alkyl" means an alkyl group having 1 to 6 carbons. 1-9"Alkyl" refers to an alkyl group containing from 1 to 9 carbon atoms, which can be Ci alkyl, C2alkyl, C3alkyl, C4alkyl, C5alkyl, C6alkyl, C7alkyl, C8alkyl, or C9alkyl, each occurrence of which is independent of the other and is optionally substituted as defined herein. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, i-propyl, n-butyl, s-butyl, t-butyl, i-butyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, i-pentyl, neopentyl, t-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-t-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, t-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyidecyl, 2-butyidecyl, 2-hexyidecyl, 2-octyidecyl, n-undecyl, n-dodecyl, 2-ethyldodecyl, 2-butyldodecyl, 2-hexyldodecyl, 2-octyldodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, 2-ethyihexadecyl, 2-butyihexadecyl, 2-hexyihexadecyl, 2-octyihexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, 2-ethyieicosyl, 2-butyieicosyl, 2-hexyieicosyl, 2-octyieicosyl, n- heneicosyl, n-docosyl, n-tricosyl, n-tetracosyl, n-pentacosyl, n-hexacosyl, n-heptacosyl, n-octacosyl, n-nonacosyl, n-triacontyl, and the like.

[0072] In the present application, "alkoxy" refers to a group of the structure "-O-alkyl", i.e., an alkyl group as defined above attached via an oxygen atom to the remainder of the molecule. Suitable examples of phrases containing this term include, but are not limited to: methoxy (-O-CH3or -OMe), ethoxy (-O-CH2CH3or -OEt), t-butoxy (-O-C(CH3)3or -OTBu), n-hexyloxy (-O-C6H 13 10 21 12 25

[0073] ​​​​​In the present application, "aryloxy" refers to a group of structure "-O-aryl", i.e. an aryl group as defined above is attached to another group via an oxygen atom. Suitable examples of phrases containing this term include, but are not limited to: phenoxy, naphthoxy, and the like. "Heteroaryloxy" refers to a group of structure "-O-heteroaryl", i.e. a heteroaryl group as defined above is attached to another group via an oxygen atom. "Alkoxyaryl" refers to a group of structure "-aryl-alkoxy", i.e. an alkoxy group as defined above is attached to another group via an aryl group, for example, hexyloxyphenyl represents -ph-OC6H 13 wherein ph represents a phenyl group.

[0074] In the present application, "alkylthio" refers to a group of structure "-S-alkyl", i.e. an alkyl group as defined above is attached to another group via a sulfur atom. Suitable examples of phrases containing this term include, but are not limited to: methylthio (-S-CH3 or -SMe), ethylthio (-S-CH2CH3 or -SEt), t-butylthio (-S-C(CH3)3 or -StBu), n-hexylthio (-S-C6H 13 ), n-decylthio (-S-C 10 H 21 ), and n-dodecylthio (-S-C 12 H 25 ). Similarly, "arylthio" refers to a group of structure "-S-aryl", and "heteroarylthio" refers to a group of structure "-S-heteroaryl".

[0075] In the present application, amino represents -NR1R2, wherein each of R1and R2independently represents H or alkyl, i.e. amino can represent -NH2, -NH(alkyl), or -Nalkyl(alkyl).

[0076] In the present application, "arylaminyl" refers to a group of structure "-NR-aryl" or "-Naryl(aryl)", i.e. an aryl group as defined above is attached to another group via an N atom, for example and the like. "Heteroarylaminyl" refers to a group of structure "-NR-heteroaryl" or "-Nheteroaryl(heteroaryl)", i.e. a heteroaryl group as defined above is attached to another group via an N atom.

[0077] In the present application, "a'' connected to a single bond" represents a connection site or a fusion site. When the connection site in a group is not specified, it means that any optional connection site in the group is the connection site. For example, , any optional connection site on the two benzene rings and the optional connection site on Z can be the connection site to the main skeleton structure; it can be understood that when Z is the optional connection site, Z is N.

[0078] In the present application, the single bond to which the substituent is attached runs through the corresponding ring, indicating that the substituent can be connected to any optional position of the ring. For example R 13 may be connected to any substitutable position in the benzene ring.

[0079] In the present application, "combination thereof", "any combination thereof", "any combination manner thereof" and the like include all suitable combination manners of any two or more items listed.

[0080] In the present application, "halogen" represents -Cl, -Br, -F or -I; "carboxyl" represents -COOH; "nitro" represents -NO2; "sulfonic acid group" represents -SO3H; "cyano" represents .

[0081] In the present application, "alkylcarbonyl" refers to a group with the structure of , and "alkoxycarbonyl" refers to a group with the structure of . In the above structures, R represents an alkyl group, and C 1-30 The C1-C 30 alkylcarbonyl group is the number of carbon atoms in the entire group.

[0082] The present application provides a composite material, comprising a hot exciton material and a fluorescent material;

[0083] The hot exciton material comprises one or more of the compounds with the following general formula: , , ;

[0084] wherein R1, R2, R6 and R7 are each independently selected from the group consisting of H, D, halogen, cyano, amino, nitro, C 1-20 alkyl, C 1-20 alkoxy, heteroaryl with 5-20 ring atoms, and C 6-20 aryl, or a combination of one or more thereof;

[0085] R3, R4, R5, R8 and R9 are each independently selected from the group consisting of a combination of one or more of substituted or unsubstituted C 6-60 aryl, substituted or unsubstituted heteroaryl with 5-60 ring atoms, substituted or unsubstituted arylamino with 6-60 ring atoms, substituted or unsubstituted aryloxy with 6-60 ring atoms, substituted or unsubstituted arylthiol with 6-60 ring atoms, substituted or unsubstituted heteroarylamino with 5-60 ring atoms, substituted or unsubstituted heteroaryloxy with 5-60 ring atoms, and substituted or unsubstituted heteroarylthiol with 5-60 ring atoms;

[0086] R3, R4, R5, R8and R9, independently at each occurrence, are selected from the group consisting of D, halogen, cyano, amino, nitro, thiol, carbonyl, C1-C20alkyl, C1-C20alkenyl, C1-C20alkoxy, C5-C30heteroaryl, and substituted or unsubstituted C6-C30aryl, in combination of one or more thereof; 1-20 C1-C20alkyl, C1-C20alkenyl, 1-20 C1-C20alkyl, C1-C20alkenyl, 1-20 C1-C20alkyl, C1-C20alkenyl, 6-30 C1-C20alkyl, C1-C20alkenyl,

[0087] The heteroatom in the heteroaryl, heteroaryloxy, heteroaryl amino, heteroaryl thiol is independently selected from one or more of O, P, N, S.

[0088] The present application provides a composite material including hot exciton introduction can achieve the simultaneous use of singlet and triplet excitons, thereby improving the utilization efficiency of exciton energy and improving the recombination efficiency of carriers, reducing the non-radiative decay process, thereby increasing the luminous efficiency and brightness. And by selecting suitable hot exciton and fluorescent material to cooperate, the light emission spectrum range of the composite material can be adjusted to cover a wider spectrum range.

[0089] Further, the above-mentioned composite material includes 96% to 99% of hot exciton material and 1% to 4% of fluorescent material in mass percentage.

[0090] In one specific example, the hot exciton material includes one or more of the following compounds having the general formula:

[0091] , , ;

[0092] wherein R 11 and R 13 are each independently selected from C 6-30 aryl;

[0093] R5, R8, R 10 , R 12 and R 14 are each independently selected from H, C 1-20 alkyl and one of the following structures: , , ;

[0094] wherein R 15 -R 19 are each independently selected from H, D, halogen, cyano, amino, nitro, substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 1-30Alkyl mercapto, substituted or unsubstituted C 1-30 The alkylamine group and the substituted or unsubstituted ring atoms have a carbon number of C. 6-30 One or more combinations of aryl groups;

[0095] Z represents a single bond, -CO-, -N-, or -CR. 20 R 21 -、-NR 21 -, phenyl, -O- or -S-;

[0096] R 20 and R 21 Each is independently selected from H, D, halogen, cyano, amino, nitro, substituted or unsubstituted C. 1-30 Alkyl, substituted or unsubstituted C 1-30 Alkoxy, substituted or unsubstituted C 1-30 Alkyl mercapto, substituted or unsubstituted C 1-30 The alkylamine group and the substituted or unsubstituted ring atoms have a carbon number of C. 1-30 One or more combinations of aryl groups; R 15 ~R 21 The substituents in the middle group are each independently selected from D, amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid, mercapto, cyano, carbonyl, and C groups, each time they appear. 1-20 Alkyl, C 1-20 alkenyl, C 1-20 Alkoxy groups, heteroaryl groups with 5-20 ring atoms, and C 6-20 One or more of the aryl groups; heteroaryl groups are selected from one or more of O, P, N, and S, and * indicates the linking site.

[0097] In a specific example, R5, R8, R 10 R 12 and R 14 Each is independently selected from H and C. 1-5 alkyl groups and one of the following groups:

[0098] ;

[0099] Among them, R 22 ~R 35 Each is independently selected from H, D, halogen, cyano, amino, nitro, C 1-20 Alkyl, C 1-20one or more of alkoxy, heteroaryl having 5 to 20 ring atoms, and aryl having C 6-20

[0100] and / or, R 11 and R 13 are each independently selected from one of the following groups:

[0101]

[0102] .

[0103] In one specific example, R5, R8, R 10 , R 12 and R 14 are each independently selected from H and one of the following groups:

[0104] .

[0105] In one specific example, R 11 and R 13 are each independently selected from one of the following groups:

[0106] .

[0107] In one specific example, the hot exciton material includes at least one of the following materials: (mPAC), ​(PABPP), (PABP), (PAC), (PPI-2NPA), (PhBPI), (TPIBNCz), (P-TXO2), (NCBAOMe), (DP-TXO2), (TPB-PAPC), and (TPB-AC).

[0108] In one specific example, the composite material further comprises a sensitizer;

[0109] wherein the sensitizer comprises one or more of the following compounds having the general formula: ;

[0110] wherein the structural unit D is a donor group, A is an acceptor group, and L is a linking group;

[0111] the donor group is selected from the group consisting of one or more of carbazolyl, arylamino, alkylamino, silyl, alkoxy, aryloxy, thio, alkylthio, arylthio, acridinyl, phenoxazinyl, thienazinyl;

[0112] the linking group is selected from the group consisting of one or more of a single bond, -0-, cycloalkylene, arylene, heteroarylene, heterocycloalkylene, heterocycloalkenylene;

[0113] the acceptor group is selected from the group consisting of one or more of fluorine, cyano, triazinyl, cyanophenyl, phosphinoyl, ketone carbonyl, sulfone, pyrrolyl, thienyl, pyrazolyl, thiazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, phenalenyl;

[0114] m and n are each independently an integer from 1 to 5;

[0115] ring C, ring E, ring F, ring G, and ring H are each independently selected from the group consisting of a substituted or unsubstituted C 6-20one or more of substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl having 5 to 20 ring atoms, substituted or unsubstituted arylamino having 6 to 20 ring atoms, substituted or unsubstituted aryloxy having 6 to 20 ring atoms, substituted or unsubstituted arylthiol having 6 to 20 ring atoms, substituted or unsubstituted heteroarylamino having 5 to 20 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 20 ring atoms, and substituted or unsubstituted heteroarylthiol having 5 to 20 ring atoms;

[0116] substituents in ring C, ring E, ring F, ring G, and ring H, each independently in the occurrence, is selected from the group consisting of D, amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid, thiol, cyano, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20 alkoxy, heteroaryl having 5 to 20 ring atoms, and C 6-20 aryl;

[0117] the heteroatoms in heterocycloalkylene, heterocycloalkenylene, heteroaryl, heteroaryloxy, heteroaryl amino, and heteroarylthiol are each independently selected from one or more of O, P, N, and S.

[0118] In one specific example, ring C, ring E, ring F, ring G, and ring H are each independently selected from substituted or unsubstituted C 6-20 aryl; substituents in ring C, ring E, ring F, ring G, and ring H, each independently in the occurrence, is selected from the group consisting of D, amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid, thiol, cyano, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20 alkoxy, heteroaryl having 5 to 20 ring atoms, and C 6-20 aryl; the heteroatoms in heteroaryl are each independently selected from one or more of O, P, N, and S.

[0119] In one specific example,

[0120] the structural unit D donor group is selected from and one or both;

[0121] the acceptor group includes and cyano;

[0122] R 36 ~R 41 each independently selected from the group consisting of D, halogen, cyano, amino, nitro, thiol, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20alkyl, alkoxy, cycloalkyl, heteroaryl, and C 6-30 a combination of one or more of aryl, heteroaryl, and C

[0123] Further, the donor group is selected from one of the following groups:

[0124] .

[0125] It is appreciated that m is 1, 4, or 5.

[0126] In one specific example, the linking group is phenyl.

[0127] Further, the acceptor group is selected from one of the following groups:

[0128] It is appreciated that n is 1 or 2.

[0129] In one specific example, C, E, F, G, and H are each independently selected from one of the following groups: 6-20 aryl.

[0130] Further, C, F, and G are each independently selected from one of the following groups:

[0131] .

[0132] Further, F and H are each independently selected from one of the following groups:

[0133] .

[0134] In one specific example, the sensitizing agent includes at least one of the following materials: (DtBuCzB), (DtBuPhCzB), (DMAC-TRZ), (4CzIPN), (5CzTRZ), and (5tBuCzTRZ).

[0135] In one specific example, the peak wavelength in the absorption spectrum of the fluorescent material is between 250 nm and 500 nm. Further, the fluorescent material includes at least one of 8-hydroxyquinoline aluminum (Alq3) and 5,6,11,12-tetraphenyl naphthacene (Rubrene).

[0136] It can be understood that the role of the thermally activated delayed fluorescence (TADF) sensitizer is that, when the carriers recombine in the light-emitting layer to form an exciton, the exciton energy is transferred to the sensitizer, and the sensitizer can emit light using both singlet and triplet excitons. The fluorescent light emitted by the sensitizer is then absorbed by the fluorescent material and emits light, thereby achieving full utilization of excitons. The thermal exciton mechanism is to improve the utilization of excitons through the reverse intersystem crossing (RISC) from the high-energy triplet state (T n , n≥2) to the singlet state (S m , m≥1). That is, the high-energy triplet state (T n , n≥2) of the thermal exciton can effectively transfer energy to the TADF sensitizer through the mechanism of Dexter energy transfer. In order to ensure more efficient energy transfer, the emission of the thermal exciton and the absorption of the sensitizer, and the emission of the sensitizer and the absorption of the fluorescent material need to have a large overlap.

[0137] In one specific example, the composition of the composite material includes 75% to 97% of the thermal exciton material, 2% to 23% of the sensitizer, and 0.01% to 5% of the fluorescent material in terms of mass percentage.

[0138] Further, the present application also provides a light-emitting device, including:

[0139] a light-emitting layer arranged between the anode and the cathode;

[0140] wherein the raw material of the light-emitting layer includes the composite material described above; or the light-emitting layer is formed of the composite material described above.

[0141] The material of the anode and the cathode are independently selected from one or both of a metal and a metal oxide, the metal including one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg; the metal oxide including one or more of a doped or undoped metal oxide including ITO, FTO, ATO, AZO, GZO, IZO, MZO, and AMO, or a composite electrode including a metal sandwiched between doped or undoped transparent metal oxides including one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2.

[0142] It is understood that the material of the anode is not particularly limited and can be any hole-transporting anode material. The anode material can include, for example, one or a combination of several of a metal, a metal oxide, and a conductive polymer. The material of the cathode is not particularly limited and can be any electron-transporting cathode material. The cathode material can include a metal such as one or a mixture of two or more of magnesium (Mg), calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum (Al), silver (Ag), tin, and lead, or an alloy of at least two of these.

[0143] In one specific example, the light-emitting device further includes a hole function layer disposed between the anode and the light-emitting layer.

[0144] In one specific example, the hole functional layer includes one or both of a hole injection layer and a hole transport layer, and when both a hole transport layer and a hole injection layer are included, the hole transport layer is disposed closer to the light emitting layer than the hole injection layer. Further, the hole injection layer is selected from one or more of poly(ethylenedioxythiophene)-poly(styrenesulfonic acid), polyarylamines, N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, 4,4',4"-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane, 4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine], 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane-doped N,N'-diphenyl-N,N'-di(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, poly(3,4-ethylenedioxythiophene)-polystyrenesulfonic acid, 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, transition metal oxides selected from one or more of NiO, MoO2, MoO3, WO3, and CuO, and transition metal chalcogenides selected from one or more of MoS2, MoSe2, WS3, WSe3, and CuS.

[0145] Further, the hole transport layer is selected from one or more of poly[(9,9-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-buty lphenyl)diphenylamine)], poly(9-vinylcarbazole), 4,4'-bis(9-carbazolyl)-2,2'-dimethylbiphenyl, 4,4'-bis(N-carbazolyl)-1,1'-biphenyl, 4,4'-di(9-carbazolyl)biphenyl, P-type phthalocyanine, copper phthalocyanine, 1,3-bis(carbazol-9-yl)benzene, and 4,4',4"-tris(carbazol-9-yl)triphenylamine.

[0146] In one specific example, the light emitting device further includes an electron functional layer disposed between the cathode and the light emitting layer.

[0147] In one specific example, the electron functional layer includes one or both of an electron injection layer and an electron transport layer, and when both an electron transport layer and an electron injection layer are included, the electron transport layer is disposed closer to the light emitting layer than the electron injection layer.

[0148] Optionally, the material of the electron transport layer is selected from one or more of 8-hydroxyquinoline aluminum, diphenyl[4-(triphenylsilyl)phenyl]phosphine oxide, 1,3,5-tris[(3-pyridyl)-3-phenyl]benzene, 2-(4'-tert-butylphenyl)-5-(4'-biphenylyl)-1,3,4-oxadiazole, beryllium octahydrate quinoline, 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole, 2,7-bis(diphenylphosphine oxide)-9,9'-spirobi[fluorene], 3,5-tris(N-phenyl-2-benzimidazole)benzene, 4,6-bis(3,5-di(2-pyridyl)phenyl)-2-methylpyrimidine, and 4,7-diphenyl-1,10-phenanthroline.

[0149] Optionally, the material of the electron injection layer includes one or more of LiF, Liq, NaF, and CsF.

[0150] The preparation method of the present application is intended to illustrate that the light-emitting layer can be formed by a composite material in a solution method. Therefore, the method for forming other functional layers of the light-emitting device is not particularly limited, for example, can include a solution method, a step of forming an anode, a cathode, a hole functional layer, and an electron functional layer by an evaporation method, etc.

[0151] Further, the present application provides a display device comprising the light-emitting device described above.

[0152] The present application also provides the use of the light-emitting device described above or the display device as described above in the preparation of an electronic device. It can be understood that the electronic device can be a display device, a lighting device, an optical communication device, or other types of electronic devices, specific examples of which include but are not limited to computer screens, mobile phone screens, televisions, electronic paper, emergency lighting, optical modules.

[0153] The present application will be further described in detail below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present application and not to limit the scope of the present application. The experimental methods in the following examples are not specified, and the priority is given to the guidance given in the present application. It can also be in accordance with the experimental manual or conventional conditions in the art, or in accordance with the conditions suggested by the manufacturer, or in accordance with the known experimental methods in the art.

[0154] In the following specific examples, the measurement parameters of the raw material components may, without specific instructions, have slight deviations within the weighing accuracy range. The temperature and time parameters allow for acceptable deviations caused by instrument testing accuracy or operating accuracy. "Normal temperature" refers to 25°C; "normal pressure" refers to 100 KPa or 101 KPa.

[0155] Example 1

[0156] As Figure 1The application provides an organic electroluminescent device 10, comprising an anode 110, a hole injection layer 120, a hole transport layer 130, a light-emitting layer 140, an electron transport layer 150 and a cathode 160 which are sequentially stacked, wherein the material of the light-emitting layer 140 comprises a composite material, and the composite material comprises, in terms of mass percentage, 98% of PAC as a hot exciton material and 2% of Alq3 as a fluorescent material.

[0157] The specific preparation steps are as follows:

[0158] The transparent conductive film ITO is used as the anode, and the thickness is 50 nm;

[0159] The polyethylene dioxythiophene-poly (styrene sulfonate) PEDOT:PSS is deposited on the ITO as a hole injection layer by a solution method, and the thickness is 30 nm;

[0160] The 4,4',4''-tris (carbazole-9-yl) triphenylamine TCTA is deposited on the hole injection layer as a hole transport layer by a solution method, and the thickness is 25 nm;

[0161] The OLED light-emitting layer material is deposited on the hole transport layer by a solution method, wherein a composite material and methyl benzoate as a solvent of the composite material are mixed, so that the concentration of the whole composite material is 20 mg / ml, and the thickness of the final light-emitting layer is 35 nm after removing the solvent;

[0162] The TmPyPB is deposited on the light-emitting layer as an electron transport layer by an evaporation method, and the thickness is 30 nm;

[0163] The Li is deposited on the electron transport layer as an electron injection layer by an evaporation method, and the thickness is 100 nm.

[0164] The Al is deposited on the electron injection layer as a cathode by an evaporation method, and the thickness is 100 nm.

[0165] Example 2

[0166] The difference from example 1 is that the material of the light-emitting layer 140 comprises a composite material, and the composite material comprises, in terms of mass percentage, 99% of PAC as a hot exciton material, 0.5% of 4CZIPN sensitizer and 0.5% of Alq3 as a fluorescent material.

[0167] Example 3

[0168] The difference from example 1 is that the composition of the composite material is different, and specifically the composite material comprises, in terms of mass percentage, 98.5% of PAC as a hot exciton material, 0.5% of 4CZIPN sensitizer and 1% of Alq3 as a fluorescent material.

[0169] Example 4

[0170] The difference from Example 1 is that the composition of the composite material is different, specifically the composite material comprises, by mass percentage, 97.5% of PAC as a hot exciton material, 0.5% of 4CZIPN as a sensitizer, and 2% of Alq3 as a fluorescent material.

[0171] Example 5

[0172] The difference from Example 1 is that the composition of the composite material is different, specifically the composite material comprises, by mass percentage, 98.5% of PAC as a hot exciton material, 1% of 4CZIPN as a sensitizer, and 0.5% of Alq3 as a fluorescent material.

[0173] Example 6

[0174] The difference from Example 1 is that the composition of the composite material is different, specifically the composite material comprises, by mass percentage, 98% of PAC as a hot exciton material, 1% of 4CZIPN as a sensitizer, and 1% of Alq3 as a fluorescent material.

[0175] Example 7

[0176] The difference from Example 1 is that the composition of the composite material is different, specifically the composite material comprises, by mass percentage, 97% of PAC as a hot exciton material, 1% of 4CZIPN as a sensitizer, and 2% of Alq3 as a fluorescent material.

[0177] Example 8

[0178] The difference from Example 3 is that the sensitizer material is replaced by DtBuCzB in equal mass.

[0179] Example 9

[0180] The difference from Example 3 is that the sensitizer material is replaced by DtBuPhCzB in equal mass.

[0181] Example 10

[0182] The difference from Example 3 is that the sensitizer material is replaced by 5tBuCZTRZ in equal mass.

[0183] Example 11

[0184] The difference from Example 3 is that the sensitizer material is replaced by 5CZTRZ in equal mass.

[0185] Example 12

[0186] The difference from Example 3 is that the sensitizer material is replaced by DMAC-TRZ in equal mass.

[0187] Example 13

[0188] The difference from Example 3 is that the fluorescent material is replaced by Rubrene.

[0189] Comparative Example 1

[0190] The difference from Example 1 is that the composite material is replaced by PAC.

[0191] Comparative Example 2

[0192] The difference from Example 3 is that the light-emitting layer is 25 nm thick and the composite material is replaced by Alq3.

[0193] Comparative Example 3

[0194] The difference from Example 3 is that the light-emitting layer is 25 nm thick and the composite material is replaced by Rubrene.

[0195] Comparative Example 4

[0196] The transparent conductive film ITO is used as the anode, and the thickness is 50 nm;

[0197] PEDOT:PSS is deposited on the ITO as a hole injection layer using a solution method, and the thickness is 30 nm;

[0198] TCTA is deposited on the hole injection layer as a hole transport layer using a solution method, and the thickness is 25 nm;

[0199] Methyl benzoate is used as a solvent for the light-emitting layer material on the hole transport layer using a solution method, and the composite material is composed of 99.5% PAC and 0.5% Alq3 as the light-emitting layer, and the thickness is 25 nm;

[0200] TmPyPB is deposited on the light-emitting layer as an electron transport layer using an evaporation method, and the thickness is 30 nm;

[0201] Li is deposited on the electron transport layer as an electron injection layer using an evaporation method, and the thickness is 100 nm.

[0202] Al is deposited on the electron injection layer as a cathode using an evaporation method, and the thickness is 100 nm.

[0203] Comparative Example 5

[0204] The transparent conductive film ITO is used as the anode, and the thickness is 50 nm;

[0205] PEDOT:PSS is deposited on the ITO as a hole injection layer using a solution method, and the thickness is 30 nm;

[0206] TCTA is deposited on the hole injection layer as a hole transport layer using a solution method, and the thickness is 25 nm;

[0207] DMAC-DPS (TADF material, CAS: 1477512-32-5) (99.5%): Alq3 (0.5%) as the light-emitting layer was deposited on the hole transport layer by solution method, with a thickness of 25 nm;

[0208] TmPyPB as the electron transport layer was deposited on the light-emitting layer by evaporation method, with a thickness of 30 nm;

[0209] Li as the electron injection layer was deposited on the electron transport layer by evaporation method, with a thickness of 100 nm.

[0210] Al as the cathode was deposited on the electron injection layer by evaporation method, with a thickness of 100 nm.

[0211] Comparative Example 6

[0212] ITO as the anode, with a thickness of 50 nm;

[0213] PEDOT:PSS as the hole injection layer was deposited on the ITO by solution method, with a thickness of 30 nm;

[0214] TCTA as the hole transport layer was deposited on the hole injection layer by solution method, with a thickness of 25 nm;

[0215] MADN (hot exciton TTA material, CAS: 804560-00-7) (99.5%): Alq3 (0.5%) as the light-emitting layer was deposited on the hole transport layer by solution method, with a thickness of 25 nm;

[0216] TmPyPB as the electron transport layer was deposited on the light-emitting layer by evaporation method, with a thickness of 30 nm;

[0217] Li as the electron injection layer was deposited on the electron transport layer by evaporation method, with a thickness of 100 nm.

[0218] Al as the cathode was deposited on the electron injection layer by evaporation method, with a thickness of 100 nm.

[0219] The OLEDs of the above examples and comparative examples were subjected to electrical tests, and the results are shown in Table 1 below, Figure 2 which is an external quantum efficiency-current density diagram.

[0220] Table 1

[0221]

[0222] V@1cd / m 2 represents the luminance of 1 cd / m 2 corresponding to the turn-on voltage;

[0223] EQE@10mA / cm 2 This indicates a current density of 10 mA / cm². 2 The corresponding external quantum efficiency (EQE) refers to the percentage of photons emitted outside the device relative to the number of injected charge carriers.

[0224] T 95 (h)@1000cd / m 2 This indicates that the device has an initial brightness of 1000 cd / m². 2 The light continues to illuminate until the brightness decreases to 95% of the initial brightness (950 cd / m²). 2 The time elapsed during which )

[0225] The batteries in Examples 1-13 of this application have a start-up voltage of 3.6V to 3.8V and a current density of 10mA / cm². 2 The external quantum efficiency was 7.1%–11.1% and the brightness decay time was 5 h–15 h. In contrast, the cells used in Comparative Examples 1–6, which used only fluorescent materials, only thermal exciton materials, and a combination of thermally activated delayed fluorescence sensitizers and fluorescent materials, had a start-up voltage of 4.3 V and a current density of 10 mA / cm². 2 The external quantum efficiency was 2.9%~4.2% and the brightness decay time was 1~2h. It can be seen that the introduction of thermal exciton materials and thermally activated delayed fluorescence sensitizers can realize the simultaneous utilization of singlet and triplet excitons, thereby improving the exciton energy utilization efficiency and carrier recombination efficiency, reducing the non-radiative decay process, and thus increasing luminescence efficiency and brightness.

[0226] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0227] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims, and the specification and drawings can be used to interpret the scope of the claims.

Claims

1. A composite material, characterized by, including a hot exciton material and a fluorescent material; The hot exciton material includes one or more of the compounds having the general formula: , , ; wherein R1, R2, R6and R7are each independently selected from the group consisting of H, D, halogen, cyano, amino, nitro, C 1-20 alkyl, C 1-20 alkoxy, a heteroaryl group having 5 to 20 ring atoms, and C 6-20 aryl, in combination of one or more kinds; R3, R4, R5, R8, and R9 are each independently selected from the group consisting of substituted or unsubstituted C 6-60 aryl, substituted or unsubstituted heteroaryl having 5 to 60 ring atoms, substituted or unsubstituted arylamino having 6 to 60 ring atoms, substituted or unsubstituted aryloxy having 6 to 60 ring atoms, substituted or unsubstituted arylmercapto having 6 to 60 ring atoms, substituted or unsubstituted heteroarylamino having 5 to 60 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 60 ring atoms, and substituted or unsubstituted heteroarylmercapto having 5 to 60 ring atoms; R3, R4, R5, R8and R9in said substituted substituent, each occurrence is independently selected from the group consisting of D, halogen, cyano, amino, nitro, thiol, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20 alkoxy, heteroaryl having 5 to 30 ring atoms, and substituted or unsubstituted C 6-30 aryl, in combination of one or more; the heteroatom in the heteroaryl group, the heteroaryloxy group, the heteroaryl amino group, and the heteroaryl mercapto group is independently selected from one or more of O, P, N, and S.

2. The composite material of claim 1, wherein, the hot exciton material includes one or more of the following compounds having the general formula: 、 、 ； wherein R 11 and R 13 are each independently selected from C 6-30 aryl; R5, R8, R 10 , R 12 and R 14 are each independently selected from H, C 1-20 alkyl and one of the following structures: 、 、 ； wherein R 15 R 19 each independently is selected from the group consisting of H, D, halogen, cyano, amino, nitro, substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 1-30 alkoxy, substituted or unsubstituted C 1-30 alkylthio, substituted or unsubstituted C 1-30 alkylamino, and substituted or unsubstituted aryl having a number of ring atoms C 6-30 or a combination of one or more of these. Z is a single bond, -CO-, -NH-, -CR 20 R 21 -, -NR 21 -, phenyl, -O- or -S-; R 20 and R 21 each independently is selected from the group of H, D, halogen, cyano, amino, nitro, substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 1-30 alkoxy, substituted or unsubstituted C 1-30 alkylthio, substituted or unsubstituted C 1-30 alkylamino, and substituted or unsubstituted aryl having a number of ring atoms of C 1-30 one or more combinations thereof; R 15 ~R 21 each of the substituents described in the substituent is, independently at each occurrence, selected from one or more of D, amino, halogen, hydroxy, carboxy, nitro, sulfonic acid, mercapto, cyano, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20 alkoxy, heteroaryl having 5 to 20 ring atoms, and C 6-20 aryl; the heteroaryl group is selected from one or more of O, P, N, and S, and * is a linking site.

3. The composite material of claim 2, wherein, R5, R8, R 10 , R 12 and R 14 are each independently selected from H, C 1-5 alkyl and one of the following groups: ； wherein R 22 R 35 each independently is selected from one or more of H, D, halogen, cyano, amino, nitro, C 1-20 alkyl, C 1-20 alkoxy, heteroaryl having 5 to 20 ring atoms, and aryl having C 6-20 ring atoms; and / or, R 11 and R 13 each independently is selected from one of the following groups: 。 4. The composite material according to any one of claims 1 to 3, wherein the hot exciton material includes at least one of the following materials: 、 、 、 、 、 、 、 、 、 、 and .

5. The composite material according to any one of claims 1 to 3, wherein The composite further includes a sensitizer; wherein the sensitizer includes one or more of the following compounds having the general formula: , ; wherein D is a donor group, A is an acceptor group, and L is a linking group; the donor group is selected from a combination of one or more of carbazolyl, arylamino, alkylamino, silyl, alkoxy, aryloxy, thio, alkylthio, arylthio, acridinyl, phenoxazinyl, and thioxanthinyl; the linking group is selected from a combination of one or more of a single bond, -O-, cycloalkylene, arylene, heteroaryl, heterocycloalkylene, and heterocycloalkenylene; the acceptor group is selected from a combination of one or more of fluorine, cyano, triazinyl, cyanophenyl, phosphineoxy, ketone carbonyl, sulfone, pyrrolyl, thiophenyl, pyrazolyl, thiazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, and phenalenyl; m and n are each independently an integer from 1 to 5; each of ring C, ring E, ring F, ring G, and ring H is independently selected from the group consisting of substituted or unsubstituted C 6-20 a combination of one or more of aryl, substituted or unsubstituted heteroaryl having 5 to 20 ring atoms, substituted or unsubstituted arylamino having 6 to 20 ring atoms, substituted or unsubstituted aryloxy having 6 to 20 ring atoms, substituted or unsubstituted arylmercapto having 6 to 20 ring atoms, substituted or unsubstituted heteroarylamino having 5 to 20 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 20 ring atoms, and substituted or unsubstituted heteroarylmercapto having 5 to 20 ring atoms; The substituents described in rings C, E, F, G, and H, each time appearing, are independently selected from D, amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid, mercapto, cyano, carbonyl, C 1-20 Alkyl, C 1-20 alkenyl, C 1-20 Alkoxy groups, heteroaryl groups with 5-20 ring atoms, and C 6-20 One or more of the aryl group; the heteroatom in the heterocycloalkylene group, the heterocycloalkenylene group, the heteroaryl group, the heteroaryloxy group, the heteroaryl amino group, and the heteroaryl mercapto group is independently selected from one or more of O, P, N, and S.

6. The composite material of claim 5, wherein, the donor group is selected from and one or both of The acceptor group includes and one or both of cyano; R 36 ~R 41 each independently selected from the group consisting of D, halogen, cyano, amino, nitro, thiol, carbonyl, C 1-20 alkyl, C 1-20 alkenyl, C 1-20 alkoxy, heteroaryl having 5 to 30 ring atoms, and C 6-30 aryl; the heteroaryl is selected from one or more of O, P, N, S; and / or, each of ring C, ring E, ring F, ring G, and ring H is independently selected from substituted or unsubstituted C 6-20 aryl; The substituents described in rings C, E, F, G, and H, each time appearing, are independently selected from D, amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid, mercapto, cyano, carbonyl, C 1-20 Alkyl, C 1-20 alkenyl, C 1-20 Alkoxy groups, heteroaryl groups with 5-20 ring atoms, and C 6-20 One or more of the aryl groups; the heteroaryl group is selected from one or more of O, P, N, and S.

7. The composite material of claim 6, wherein, the sensitizing agent includes at least one of the following materials: 、 、 , , and 。 8. The composite material of claim 5, wherein, a peak wavelength in an absorption spectrum of the fluorescent material is between 250 nm and 500 nm; and / or, the composite material includes, in mass percentage, 75% to 97% of the hot exciton material, 2% to 23% of the sensitizing agent, and 0.01% to 5% of the fluorescent material; and / or, the fluorescent material includes at least one of 8-hydroxyquinoline aluminum and 5,6,11,12-tetraphenyl naphthacene.

9. A light-emitting device, characterized in that, comprising: oppositely arranged anode and cathode, and a light-emitting layer disposed between the anode and the cathode; wherein a material of the light-emitting layer includes the composite material according to any one of claims 1 to 8; or the light-emitting layer is formed of the composite material according to any one of claims 1 to 8.

10. The light emitting device of claim 9, wherein, the light-emitting device further includes a hole functional layer and an electron functional layer, the hole functional layer is disposed between the anode and the light-emitting layer, and the electron functional layer is disposed between the light-emitting layer and the cathode; the hole functional layer includes a hole transport layer and / or a hole injection layer disposed in a stack, and when both the hole transport layer and the hole injection layer are included, the hole transport layer is disposed closer to the light-emitting layer than the hole injection layer; Optionally, the material of the hole transport layer comprises one or more of poly[(9,9-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-buty lphenyl)diphenylamine)], poly(9-vinylcarbazole), 4,4'-bis(9-carbazolyl)-2,2'-dimethylstilbene, 4,4'-bis(N-carbazolyl)-1,1'-biphenyl, 4,4'-di(9-carbazolyl) biphenyl, P-type phthalocyanine, copper phthalocyanine, 1,3-bis(carbazol-9-yl)benzene, and 4,4',4''-tris(carbazol-9-yl)triphenylamine; Optionally, the material of the hole injection layer is selected from one or more of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), polyarylamine, N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, 4,4',4"-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane, 4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine], 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane-doped N,N'-diphenyl-N,N'-di(1-naphthyl)-1,1'-biphenyl-4,4''diamine, poly(3,4-ethylenedioxythiophene)-polystyrenesulfonic acid, 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, transition metal oxide selected from one or more of NiO, MoO2, MoO3, WO3, and CuO, and transition metal chalcogenide selected from one or more of MoS2, MoSe2, WS3, WSe3, and CuS; and / or the electron functional layer comprises an electron transport layer and / or an electron injection layer arranged in a stacked manner, when both the electron transport layer and the electron injection layer are included, the electron transport layer is arranged closer to the light-emitting layer than the electron injection layer; Optionally, the material of the electron transport layer is selected from one or more of aluminum quinolate, diphenyl[4-(triphenylsilyl)phenyl]phosphine oxide, 1,3,5-tris(m-pyridin-3-ylphenyl)benzene, 2-(4'-tert-butylphenyl)-5-(4'-biphenylyl)-1,3,4-oxadiazole, beryllium octa-hydroxyquinolate, 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole, 2,7-bis(diphenylphosphine oxide)-9,9'-spirobi[fluorene], 3,5-tris(N-phenyl-2-benzimidazolyl)benzene, 4,6-bis(3,5-di(2-pyridyl)phenyl)-2-methylpyrimidine, and 4,7-diphenyl-1,10-phenanthroline; Optionally, the material of the electron injection layer comprises one or more of LiF, Liq, NaF, and CsF. Optionally, the material of the anode and the cathode are independently selected from one or both of a metal and a metal oxide, the metal comprising one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg, and the metal oxide comprising one or more of a doped or undoped metal oxide comprising one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, and AMO, or a composite electrode comprising a metal sandwiched between doped or undoped transparent metal oxides comprising one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2.

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