Light emitting device, display device

Abstract

The application provides a light-emitting device and a display device, and relates to the technical field of display. The light-emitting device comprises a first electrode and a second electrode; at least one light-emitting layer is located between the first electrode and the second electrode; the light-emitting layer comprises at least one host material and at least one second component; the host material comprises a first compound, and the second component comprises a second compound; the first compound and the second compound have a first group; the structure of the first group comprises wherein, 0.1 eV <= T1 (first compound) - T1 (second compound) <= 0.5 eV, and T1 is a first triplet energy level. The application provides a light-emitting device, which has high light-emitting efficiency, high light-emitting layer quality and long service life.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a light emitting device and a display device. BACKGROUND

[0002] Organic light emitting diode (OLED) has the advantages of low power consumption, high efficiency, self-luminous and fast response speed.

[0003] The light emitting material of the OLED light emitting device generally adopts fluorescent material or phosphorescent material, and the internal quantum efficiency of the phosphorescent material is generally higher than that of the fluorescent material, so that the OLED light emitting device based on the phosphorescent light emitting mechanism has attracted much attention recently.

[0004] In the related art, the efficiency and the service life of the red phosphorescent light emitting device and the green phosphorescent light emitting device can basically meet the commercial demand, but the blue phosphorescent light emitting device has low light emitting efficiency and short service life, and has high application cost. SUMMARY

[0005] Embodiments of the present application provide a light emitting device and a display device, the light emitting device has high light emitting efficiency and long service life.

[0006] To achieve the above-mentioned purpose, embodiments of the present application adopt the following technical solutions:

[0007] In a first aspect, a light emitting device is provided, the light emitting device comprising:

[0008] a first electrode and a second electrode;

[0009] at least one light emitting layer between the first electrode and the second electrode;

[0010] The light emitting layer comprises at least one host material and at least one second component, the host material comprises a first compound, and the second component comprises a second compound;

[0011] The first compound and the second compound have a first group;

[0012] The structure of the first group comprises ;

[0013] Wherein, a represents the number of Z1, b represents the number of Z2, and c represents the number of Z3; a, b and c are independently selected from 0 or 1;

[0014] Z1, Z2 and Z3 respectively comprise one of boron, phosphorus, nitrogen, substituted or unsubstituted methine and substituted or unsubstituted silyl;

[0015] (Z1)a , (Z2) b and (Z3) c the total number of included nitrogen atoms is less than or equal to 2;

[0016] Y includes carbon or silicon;

[0017] Cy includes one of substituted or unsubstituted C5 to C30 aromatic groups, and substituted or unsubstituted C5 to C40 heteroaromatic groups;

[0018] wherein, 0.1 eV ≤ T1 (first compound) - T1 (second compound) ≤ 0.5 eV, T1 is the first triplet energy level.

[0019] Optionally, the first compound further includes a second group, the second group and the first group are linked;

[0020] the structure of the second group includes one of substituted or unsubstituted

[0021] or ;

[0022] wherein, d represents the number of L1, d is selected from 0 or 1; L1 includes one of substituted or unsubstituted C6 to C60 arylene groups;

[0023] L2 and L3 respectively include one of substituted or unsubstituted C1 to C40 alkyl groups, and substituted or unsubstituted C6 to C60 aryl groups.

[0024] Optionally, the structure includes

[0025] or ;

[0026] the structure includes

[0027] or ;

[0028] wherein, (Ra1) n represents n identical or different Ra1 substituents, (Ra2) n represents n identical or different Ra2 substituents, (Ra3) n represents n identical or different Ra3 substituents, (Ra4) n represents n identical or different Ra4 substituents, (Ra5) n represents n identical or different Ra5 substituents, (Ra6) nrepresents n identical or different Ra6substituents, (Ra7) n represents n identical or different Ra7substituents, (Ra8) n represents n identical or different Ra8substituents;

[0029] (Ra1) n , (Ra2) n , (Ra3) n , and (Ra4) n n in each of (Ra5) n , (Ra6) n , (Ra7) n , and (Ra8) n is selected from one of 0, 1, 2, 3, and 4;

[0030] Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7, and Ra8each include one of deuterium, halogen, hydroxyl, nitro, nitrile, substituted or unsubstituted amino, substituted or unsubstituted carboxyl, substituted or unsubstituted silyl, substituted or unsubstituted boryl, substituted or unsubstituted aldehydic, substituted or unsubstituted phosphorous hydroxyl, substituted or unsubstituted phosphorous alkyl, substituted or unsubstituted sulfenic acid, substituted or unsubstituted sulfinic acid, substituted or unsubstituted sulfonic acid, substituted or unsubstituted C1 to C40 linear alkyl, alkoxy, thioalkoxy, substituted or unsubstituted C3 to C20 branched alkylene, branched alkoxy, branched thioalkoxy, and substituted or unsubstituted C3 to C20 cyclic alkylene, cyclic alkoxy, cyclic thioalkoxy.

[0031] Optionally, the structure of the second compound includes:

[0032]

[0033] wherein M includes platinum or palladium; at least one of R1, R2, R3, and R4includes the first group, substituted or unsubstituted;

[0034] R1, R2, R3, and R4each include one of the first group, aryl, cyclic alkyl, cyclic alkenyl, heteroaryl, heterocyclic, carbene, and n-heterocyclic carbene, substituted or unsubstituted;

[0035] A1, A2, A3, and A4form a coordinate or covalent bond with M, A1, A2, A3, and A4each include one of carbon, nitrogen, oxygen, sulfur, boron, phosphorous, and silicon;

[0036] wherein e represents the number of X1, f represents the number of X2, and g represents the number of X3; e, f and g are independently selected from 0 or 1;

[0037] X1, X2 or X3 comprises one of oxygen, sulfur, sulfoxide, carbonyl, substituted or unsubstituted imine, methylene, phosphorane, silane, boryl, substituted or unsubstituted C1 to C40 straight-chain alkylene, alkyloxy, thioalkyloxy, substituted or unsubstituted C2 to C40 alkenylene, alkynylene, substituted or unsubstituted C3 to C20 branched alkylene, branched alkyloxy, branched thioalkyloxy, substituted or unsubstituted C3 to C20 cyclic alkylene, cyclic alkyloxy, cyclic thioalkyloxy, substituted or unsubstituted C5 to C60 arylene, and substituted or unsubstituted C5 to C60 heteroarylene.

[0038] Optionally, the second component comprises a guest material, and the guest material comprises the second compound, and the second compound is a phosphorescent material.

[0039] Optionally, the light-emitting layer further comprises at least one third component.

[0040] The second component comprises a sensitizing agent, and the third component comprises a guest material.

[0041] The sensitizing agent comprises the second compound, and the guest material comprises a fluorescent material.

[0042] Optionally, the light-emitting device further comprises a hole transport layer and an electron transport layer.

[0043] The hole transport layer is located between the first electrode and the light-emitting layer, and the electron transport layer is located between the second electrode and the light-emitting layer.

[0044] At least one of the hole transport layer and the electron transport layer comprises the second compound.

[0045] Optionally, the LUMO energy level of the second compound in the electron transport layer is less than or equal to -2.5 eV, wherein LUMO is the lowest unoccupied orbital.

[0046] Optionally, the light-emitting wavelength of the second compound ranges from 430 nm to 490 nm.

[0047] In a second aspect, the embodiments of the present application provide a display device comprising the light-emitting device according to any one of the first aspect.

[0048] This application provides a light-emitting device and a display device, wherein the light-emitting device includes: a first electrode, a second electrode, and at least one light-emitting layer; the light-emitting layer is located between the first electrode and the second electrode; the light-emitting layer includes at least one host material and at least one second component, the host material includes a first compound, and the second component includes a second compound; the first compound and the second compound have a first group; the structure of the first group includes...

[0049] Where a represents the number of Z1, b represents the number of Z2, and c represents the number of Z3; a, b, and c are independently selected from 0 or 1; Z1, Z2, and Z3 each include one of boron, phosphorus, nitrogen, substituted or unsubstituted methine, and substituted or unsubstituted silyl groups; (Z1) a (Z2) b and (Z3) c The total number of nitrogen atoms included is less than or equal to 2; Y includes carbon or silicon; Cy includes one of the following: substituted or unsubstituted C5 to C30 aromatic groups and substituted or unsubstituted C5 to C40 heteroaromatic groups; wherein 0.1eV≤T1(first compound)-T1(second compound)≤0.5eV, and T1 is the first triplet energy level.

[0050] Thus, both the first compound and the second compound have the first group; the first compound and the second compound with the first group have a higher T1 energy level, which can increase the energy transfer efficiency of triplet excitons, thereby improving the luminescence efficiency; and can satisfy 0.1eV≤T1(first compound)-T1(second compound)≤0.5eV, which can prevent the energy of the second component from being transferred back to the host material, thereby avoiding the degradation of the host material, improving the quality of the host material, and extending the life of the light-emitting device. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 This is a schematic diagram of the structure of a light-emitting device provided in an embodiment of the present invention;

[0053] Figure 2 This is a schematic diagram of another light-emitting device provided in an embodiment of the present invention;

[0054] Figure 3This is a schematic diagram of the structure of a light-emitting device provided in an embodiment of the present invention. Detailed Implementation

[0055] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0056] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this application. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific feature, structure, material, or characteristic may be included in any suitable manner in any one or more embodiments or examples.

[0057] Additionally, it should be noted that when describing the elements and embodiments thereof in this application, the articles “a,” “an,” “the,” and “the” are intended to indicate the presence of one or more elements; unless otherwise stated, “multiple” means two or more; the terms “comprising,” “including,” “containing,” and “having” are intended to be inclusive and indicate that additional elements may exist besides those listed; the terms “first,” “second,” “third,” etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or order of formation.

[0058] In related technologies, the efficiency and lifespan of red and green phosphorescent light-emitting devices can basically meet commercial requirements. However, blue phosphorescent light-emitting devices have lower luminous efficiency and shorter lifespan. On the one hand, the stability of iridium (Ir) or platinum (Pt) complexes used as blue light-emitting materials in related technologies is low, resulting in a short lifespan of the light-emitting devices. On the other hand, the non-radiative decay rate (knr) and effective radiative decay rate (kr) of the blue light-emitting materials in related technologies may be high, resulting in low external quantum efficiency of the complexes, which in turn leads to low luminous efficiency.

[0059] Among them, the effective radiation decay rate is the rate at which triplet excitons transition to the ground state through phosphorescence emission. After absorbing electric field energy, phosphorescent materials generate triplet excitons, and the process of triplet excitons transitioning to the ground state through phosphorescence emission is called effective radiation.

[0060] The nonradiative decay rate is the rate at which a triplet exciton returns to the ground state nonradiatively. This nonradiative return to the ground state includes triplet exciton-triplet exciton quenching. Triplet excitons and the ground state belong to different multiplicity states, and their direct transition rates are relatively low. Therefore, triplet excitons typically have a longer lifetime and are prone to triplet exciton-triplet exciton quenching. Triplet exciton-triplet exciton quenching generates ground state and singlet excitons, which do not emit phosphorescence.

[0061] Based on this, embodiments of the present invention provide a light-emitting device, referring to... Figure 1 ,include:

[0062] First electrode 1 and second electrode 3;

[0063] At least one light-emitting layer 2 is located between the first electrode 1 and the second electrode 3;

[0064] The light-emitting layer 2 includes at least one host material and at least one second component, wherein the host material includes a first compound and the second component includes a second compound;

[0065] The first compound and the second compound have a first group;

[0066] The structure of the first group includes ;

[0067] Where a represents the number of Z1, b represents the number of Z2, and c represents the number of Z3; a, b, and c are each independently selected from 0 or 1.

[0068] Z1, Z2 and Z3 each include one of boron (B), phosphorus (P), nitrogen (N), substituted or unsubstituted methine (CH2) and substituted or unsubstituted silyl group (SiH2);

[0069] (Z1) a (Z2) b and (Z3) c The total number of nitrogen atoms included is less than or equal to 2;

[0070] Y includes carbon or silicon;

[0071] Cy includes one of substituted or unsubstituted C5 to C30 aromatic groups and substituted or unsubstituted C5 to C40 heteroaromatic groups;

[0072] Where 0.1eV≤T1(first compound)-T1(second compound)≤0.5eV, T1 is the first triplet energy level.

[0073] In this application embodiment, the light-emitting device includes an OLED (Organic Light Emitting Diode) light-emitting device.

[0074] In an exemplary embodiment, the first electrode 1 can be an anode and the second electrode 3 can be a cathode.

[0075] For example, the material of the first electrode 1 can be a transparent metal oxide, such as any one of indium tin oxide (ITO), indium zinc oxide (IZO) or zinc oxide (ZnO);

[0076] Alternatively, the first electrode 1 may include a transparent conductive layer and a reflective metal layer stacked together. The transparent conductive layer may be made of a transparent metal oxide, such as any one of indium tin oxide (ITO), indium zinc oxide (IZO), or zinc oxide (ZnO). The reflective metal layer may be made of any one of lithium (Li), calcium (Ca), lithium fluoride (LiF), lithium fluoride (LiF), aluminum (Al), silver (Ag), magnesium (Mg), or gold (Au).

[0077] For example, the material of the second electrode 3 can be a metal, such as at least one of aluminum (Al), silver (Ag) and magnesium (Mg);

[0078] Alternatively, the material of the second electrode 3 can be an alloy, for example, the alloy can be at least one of magnesium-silver alloy, magnesium-aluminum alloy and aluminum-silver alloy.

[0079] The aforementioned light-emitting device can be a top-emitting device or a bottom-emitting device; there is no limitation here, and the specific choice depends on the actual situation.

[0080] In some embodiments, refer to Figure 1 The light-emitting device includes one light-emitting layer 2; in other embodiments, the light-emitting device includes at least two light-emitting layers 2.

[0081] In this embodiment of the application, the light-emitting layer 2 includes at least one main material and at least one second component. For example, the light-emitting layer 2 includes one main material and one second component; or, the light-emitting layer 2 includes two main materials and one second component; or, the light-emitting layer 2 includes one main material and two second components; or, the light-emitting layer 2 includes two main materials and two second components.

[0082] In some embodiments, the second component is a guest material; in other embodiments, the second component is a sensitizer, and the light-emitting layer 2 further includes a third component, which is a guest material.

[0083] When the second component is a guest material, the light-emitting layer 2 includes a host material and a guest material. In this case, the light-emitting principle of the light-emitting layer 2 is as follows: after the host material absorbs electric field energy, it generates triplet excitons. The triplet excitons of the host material transfer energy to the triplet excitons of the guest material. The triplet excitons of the guest material transition back to the ground state and emit phosphorescence.

[0084] When the second component is a sensitizer, the luminescent layer 2 includes a host material, a sensitizer, and a guest material. In this case, the luminescence principle of the luminescent layer 2 is as follows: after the host material absorbs electric field energy, it generates triplet excitons. The triplet excitons of the host material transfer energy to the triplet excitons of the sensitizer. Then, the sensitizer transfers the energy of the triplet excitons to the singlet excitons of the guest material. The singlet excitons of the guest material transition back to the ground state and emit fluorescence.

[0085] In this embodiment of the application, the main material includes a first compound, for example, the first compound may be a phosphorescent material;

[0086] The second component includes a second compound, for example, the second compound may be a phosphorescent material.

[0087] In some embodiments of this application, the first compound is a blue phosphorescent material; in some embodiments of this application, the second compound is a blue phosphorescent material.

[0088] In the embodiments of this application, 0.1eV ≤ T1 (first compound) - T1 (second compound) ≤ 0.5eV, where T1 is the first triplet energy level. For example, T1 (first compound) - T1 (second compound) can be 0.1eV, 0.2eV, 0.3eV, 0.4eV, or 0.5eV.

[0089] The first triplet energy level of the first compound is higher than that of the second compound. The triplet excitons of the host material transfer energy to the triplet excitons of the guest material at a higher rate. This also prevents the energy of the triplet excitons of the second compound from being transferred back to the first compound, which is the host material. This avoids the degradation of the host material, improves the quality of the host material, and extends the lifespan of the light-emitting device.

[0090] In the embodiments of this application, both the first compound and the second compound include a first group.

[0091] For example, the first compound includes one first group, or the first compound includes two or more first groups;

[0092] For example, the second compound includes one first group, or the second compound includes two or more first groups.

[0093] The a, b, and c of the first group are each independently selected from 0 or 1;

[0094] For example, when a is 0, the first group does not include Z1; when a is 1, the first group includes Z1.

[0095] When b is 0, the first group does not include Z2; when b is 1, the first group includes Z2.

[0096] When c is 0, the first group does not include Z3; when c is 1, the first group includes Z3.

[0097] Preferably, Z1, Z2 and Z3 are selected from nitrogen (N) or substituted or unsubstituted methine (CH), so that the structure of the first group is more stable.

[0098] The hydrogen (H) in the methine (CH) and silyl (SiH) groups of Z1, Z2, and Z3 can be substituted with R groups, including deuterium (-D), hydroxyl (-OH), halogen (-F, -Cl, -Br, -I), nitro (-NO2), nitrile (-CN), substituted or unsubstituted amino (-NH2), substituted or unsubstituted carboxyl (-C(=O)OH), substituted or unsubstituted silyl (-SiH3), substituted or unsubstituted borane (BH2), and substituted or unsubstituted formaldehyde. (-C(=O)H), substituted or unsubstituted phosphohydroxy (-P(=O)H2), substituted or unsubstituted phosphoalkyl (-PH2), substituted or unsubstituted hyposulfonic acid group (-S(=O)H), substituted or unsubstituted sulfinic acid group (-S(=O)2H), substituted or unsubstituted sulfonic acid group (-OSO2H), substituted or unsubstituted C1 to C40 straight-chain alkyl, alkoxy or thioalkoxy, substituted or unsubstituted C3 to C20 branched or cyclic alkyl, alkoxy or thioalkoxy.

[0099] (Z1) a (Z2) b and (Z3) c The total number of nitrogen atoms included is less than or equal to 2, for example, (Z1). a (Z2) b and (Z3) c The total number of nitrogen atoms included can be 0, 1, or 2.

[0100] Cy includes one of substituted or unsubstituted C5 to C30 aromatic groups and substituted or unsubstituted C5 to C40 heteroaromatic groups;

[0101] In an exemplary embodiment, an aromatic group refers to a functional group or substituent derived from an aromatic ring.

[0102] For example, aromatic groups include, but are not limited to, phenyl, naphthyl, anthraceneyl, acenaphtheneyl, indole, phenanthryl, azulene, pyrene, fluorenyl, peryl, spirofluorenyl, spirobisfluorenyl, benzophenanthryl, benzoanthryl, fluoranyl, famyl, tetraphenyl, and indolephenyl.

[0103] In an exemplary embodiment, a heteroaromatic group refers to a group in which at least one carbon atom in the aromatic ring is replaced by a heteroatom. Heteroatoms include, but are not limited to, nitrogen, sulfur, or oxygen atoms. A heteroaromatic group includes at least one of nitrogen, sulfur, or oxygen atoms.

[0104] The number of heteroatoms included in the heteroaromatic group is not limited here; it can be determined based on the actual situation.

[0105] For example, heteroaromatic groups include, but are not limited to, benzoxazolyl, benzothiazolyl, indole, benzimidazolyl, pyrroloyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, tetraazinyl, imidazolyl, pyrazolyl, carbazoleyl, thiopheneyl, thiazolyl, benzocarbazoleyl, dibenzocarbazoleyl, indole-carbazoleyl, indo-carbazoleyl, quinolinyl, isoquinolinyl, phthalazinyl, quinoxalinyl, cenolinyl, quinoxalinyl, phthalazinyl, benzoquinolinyl, benzoisoquinolinyl, benzoquinoxalinyl, benzoquinoxalinyl, acridineyl, phenanthrolinel, furanyl, pyranyl, oxazinyl, oxazolyl, oxadiazolyl, triazolyl, dioxinyl, benzofuranyl, dibenzofuranyl, thiopyranyl, thiazolyl, phenylthiol, and N. Replaced spirofluorene group.

[0106] In the embodiments of this application, both the first compound and the second compound have a first group; the first triplet energy level T1 of the first compound and the second compound having the first group is relatively high, the triplet excitons of the host material transfer energy to the triplet excitons of the guest material with higher efficiency, and the triplet excitons of the guest material have higher efficiency in transitioning back to the ground state to emit phosphorescence, thereby improving the luminescence efficiency; and it can satisfy 0.1eV≤T1(first compound)-T1(second compound)≤0.5eV, so as to prevent the energy of the second component from being transferred back to the host material, thereby avoiding the deterioration of the host material, improving the quality of the host material, and extending the life of the light-emitting device.

[0107] Optionally, the first compound further includes a second group, which is linked to the first group;

[0108] The structure of the second group can be substituted or unsubstituted.

[0109] or ;

[0110] Wherein, d represents the number of L1, and d is selected from 0 or 1; L1 includes one of the substituted or unsubstituted C6 to C60 aryl groups;

[0111] L2 and L3 each comprise one of a substituted or unsubstituted C1 to C40 alkyl group and a substituted or unsubstituted C6 to C60 aryl group, respectively.

[0112] In this embodiment of the application, when d is 0... Excluding L1; when d is 1, Including L1.

[0113] In some embodiments, L2 and L3 are connected in a ring.

[0114] In this embodiment, the second group may have at least one substituent group. This embodiment does not specifically limit the substitution position and number of substituent groups, which can be determined according to the actual situation.

[0115] In the embodiments of this application, the first compound has a first group and a second group, which are bonded together. The first compound with the above structure is structurally stable and has a high first triplet T1 energy level. The triplet excitons of the host material transfer energy to the triplet excitons of the guest material with high efficiency, thereby improving the quality of the host material and extending the lifespan of the light-emitting device.

[0116] Optional, structure include

[0117] or ;

[0118] structure include

[0119] or ;

[0120] Among them, (Ra1) n This indicates that (Ra2) has n identical or different Ra1 substituents. n This indicates that (Ra3) has n identical or different Ra2 substituents. n This indicates that (Ra4) has n identical or different Ra3 substituents. n This indicates that (Ra5) has n identical or different Ra4 substituents. n This indicates that (Ra6) has n identical or different Ra5 substituents. n This indicates that there are n identical or different Ra6 substituents, (Ra7) n This indicates that (Ra8) has n identical or different Ra7 substituents. nThis indicates that there are n identical or different Ra8 substituents;

[0121] (Ra1) n (Ra2) n (Ra3) n and (Ra4) n In this context, n is selected from one of the following: 0, 1, 2, 3, 4, or 5; (Ra5) n (Ra6) n (Ra7) n and (Ra8) n The 'n' in the equation is selected from one of 0, 1, 2, 3, or 4.

[0122] Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7, and Ra8 respectively include deuterium (-D), halogen (-F, -Cl, -Br, -I), hydroxyl (-OH), nitro (-NO2), nitrile (-CN), substituted or unsubstituted amino (-NH2), substituted or unsubstituted carboxyl (-COOH), substituted or unsubstituted silyl (-SiH3), substituted or unsubstituted borane (-BH2), substituted or unsubstituted aldehyde (-C(=O)H), substituted or unsubstituted phosphorohydroxy (-P(=O)H2), substituted or unsubstituted phosphoroalkyl (-PH2), substituted or unsubstituted sulfenic acid (-S(=O)H), substituted or unsubstituted sulfinic acid (-S(=O)2H), and substituted or unsubstituted sulfonic acid (-S(=O)2H). -OSO2H), substituted or unsubstituted C1 to C40 straight-chain alkyl, alkoxy, thioalkoxy, substituted or unsubstituted C3 to C20 branched alkylene, branched alkoxy, branched thioalkoxy, and one of substituted or unsubstituted C3 to C20 cycloalkylene, cycloalkoxy, cyclothioalkoxy.

[0123] The substituents R of the first group Z1, Z2 and Z3 and the substituents Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7 and Ra8 of the second group include Ar substituents and R' substituents;

[0124] The substituent Ar includes one of the aryl or heteroaryl groups from C5 to C60, and Ar may have one or more R' substituents;

[0125] R' substituents include deuterium (-D), halogen (-F, -Cl, -Br, -I), nitrile (-CN), C1 to C20 aliphatic hydrocarbon group, unsubstituted C5 to C30 aryl or heteroaryl, and at least one of the following: deuterium (-D), halogen (-F, -Cl, -Br, -I), nitrile (-CN), and C1 to C4 aliphatic alkyl group substituted with C5 to C30 aryl or heteroaryl.

[0126] It should be noted that at least two of the R, Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7, Ra8, Ar, and R' groups in the same compound can be linked to form a ring. For example, two R substituents can be linked to form a ring, Ra1 and Ra2 can be linked to form a ring, Ra1 and Ar can be linked to form a ring, and Ar and R' can be linked to form a ring.

[0127] In the embodiments of this application, at least one methylene group of R, Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7, or Ra8 can be replaced by a linking group X4. Linking group X4 includes an oxygen atom (-O-), a sulfur atom (-S-), a selenium atom (-Se-), a thionyl group (-SO-), a sulfinyl group (-SO2-), a carbonyl group (-C(=O)-), a thiocarbonyl group (-C(=S)-), a selenocarbonyl group (-C(=Se)-), an ester group (-C(=O)O-), or an ethylene group. At least one of the following: alkynyl (-C≡C-), substituted or unsubstituted vinylene (-CH=CH-), substituted or unsubstituted silylene (-SiH2-), substituted or unsubstituted imino (-NH-), substituted or unsubstituted ketimino (-C(=NH)-), substituted or unsubstituted methyleneamide (-C(=O)NH-), substituted or unsubstituted phosphorous hydroxyl (-P(=O)H2-), substituted or unsubstituted C5 to C60 arylene, and substituted or unsubstituted C5 to C60 heteroarylene.

[0128] In some embodiments, the multiple linking groups X4 are not adjacent to each other.

[0129] Additionally, the linking group X4 in R, Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7, or Ra8 may have at least one R' substituent.

[0130] The embodiments of this application do not specifically limit the substitution positions and substitution amounts of the linkage groups X4 R, Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7, Ra8, Ar, and R', which can be determined according to the actual situation.

[0131] In the embodiments of this application, the first compound having a first group and a second group has a stable structure and a high T1 energy level, which improves the quality of the host material and extends the lifespan of the light-emitting device.

[0132] For example, the first compound may include any of the following structures:

[0133]

[0134] Optionally, the structure of the second compound includes:

[0135]

[0136] Wherein, M includes platinum or palladium; at least one of R1, R2, R3 and R4 includes a substituted or unsubstituted first group;

[0137] R1, R2, R3 and R4 each include one of the following: substituted or unsubstituted first group, aryl, cycloalkyl, cycloalkenyl, heteroaryl, heterocyclic, carbene and n-heterocyclic carbene;

[0138] A1, A2, A3, and A4 form coordinate or covalent bonds with M, where A1, A2, A3, and A4 respectively include one of carbon, nitrogen, oxygen, sulfur, boron, phosphorus, and silicon.

[0139] Where e represents the number of X1, f represents the number of X2, and g represents the number of X3; e, f, and g are each independently selected from 0 or 1.

[0140] X1, X2, and X3 respectively include one of the following: oxygen (-O-), sulfur (-S-), thionyloxy (-SO2-), carbonyl (-C(=O)-), substituted or unsubstituted imino (-NH-), methylene (-CH2-), phosphoryloxy (-PH-), silyloxy (-SiH2-), boronyloxy (-BH-), substituted or unsubstituted C1 to C40 straight-chain alkylene, alkoxy, thionyloxy, substituted or unsubstituted C2 to C40 alkenyl, alkyneyl, substituted or unsubstituted C3 to C20 branched alkylene, branched alkoxy, branched thionyloxy, substituted or unsubstituted C3 to C20 cycloalkylene, cycloalkoxy, cyclothionyloxy, substituted or unsubstituted C5 to C60 aryl, and substituted or unsubstituted C5 to C60 heteroaryl.

[0141] In the second compound, M includes platinum (Pt) or palladium (Pd). A1, A2, A3, and A4 form coordinate or covalent bonds with M. In the covalent bond, M provides an electron pair with each of A1, A2, A3, or A4. In the coordinate bond, A1, A2, A3, or A4 provides a lone electron pair, and M provides an empty orbital.

[0142] It should be noted that M forms a coordinate bond with at least one of A1, A2, A3 and A4, and the second compound is a coordination compound.

[0143] In some embodiments, one of R1, R2, R3, and R4 includes a substituted or unsubstituted first group; in other embodiments, at least two of R1, R2, R3, and R4 include a substituted or unsubstituted first group.

[0144] In the second compound, e, f, and g are each independently selected from 0 or 1;

[0145] For example, when e is 0, the second compound does not include X1; when a is 1, the second compound includes X1.

[0146] When f is 0, the second compound does not include X2; when b is 1, the second compound includes X2.

[0147] When g is 0, the second compound does not include X3; when c is 1, the second compound includes X3.

[0148] In the embodiments of this application, the substituents of R1, R2, R3, R4, X1, X2, and X3 each include an R group. The specific structure of the R group is described above.

[0149] The embodiments of this application do not specifically limit the substitution position and number of R groups in R1, R2, R3, R4, X1, X2 and X3, which can be determined according to the actual situation.

[0150] Furthermore, at least one methylene group of X1, X2, and X3 can be replaced by a linking group X4, wherein the multiple methylene groups replaced by the linking group X4 are not adjacent. The specific structure of the linking group X4 is described above.

[0151] Among them, the linking group X4 in X1, X2 or X3 may have at least one R group.

[0152] In this embodiment of the application, there are The second compound of the structure has a higher T1 energy level, which can increase the energy transfer efficiency of triplet excitons, thereby improving the luminescence efficiency; and the structure of the second compound is stable, which improves the quality of the second component of the light-emitting layer 2 and extends the lifetime of the light-emitting device.

[0153] For example, the second compound may include any of the following structures:

[0154]

[0155] Optionally, the second component includes a guest material, which includes a second compound, which belongs to the phosphorescent material category.

[0156] In some embodiments, the doping concentration of the second compound is greater than or equal to 5%. For example, the doping concentration of the second compound can be 5%, 6%, 7%, 8%, 9%, or 10%, depending on the actual setting.

[0157] In this embodiment, the host material includes a first compound, and the guest material includes a second compound. The first triplet energy level T1 of the second compound is relatively high, and the efficiency of the triplet exciton transition of the guest material back to the ground state to emit phosphorescence is relatively high, thereby improving the luminescence efficiency. The first compound also has a relatively high T1 energy level, and can satisfy 0.1eV≤T1(first compound)-T1(second compound)≤0.5eV. This can prevent the energy of the guest material from being transferred back to the host material, thereby avoiding the degradation of the host material, improving the quality of the host material, and extending the lifespan of the light-emitting device.

[0158] Optionally, the emission wavelength of the second compound is in the range of 430 nm to 490 nm.

[0159] For example, the emission wavelength of the second compound can be 430 nm, 440 nm, 450 nm, 460 nm, 470 nm, 480 nm or 490 nm.

[0160] In this embodiment, the emission wavelength of the second compound is in the range of 430nm~490nm, which belongs to blue phosphorescent luminescent material. The second compound has a high T1 energy level, which can increase the energy transfer efficiency of triplet excitons, thereby improving the luminous efficiency of the blue phosphorescent emitter. In addition, the structure of the second compound is stable, which improves the quality of the blue phosphorescent guest in the luminescent layer 2 and extends the life of the luminescent device.

[0161] Optionally, the luminescent layer 2 further includes at least one third component; the second component includes a sensitizer, and the third component includes a guest material; the sensitizer includes a second compound, and the guest material includes a fluorescent material.

[0162] In some embodiments, the doping concentration of the second compound is greater than or equal to 5%. For example, the doping concentration of the second compound can be 5%, 6%, 7%, 8%, 9%, or 10%, depending on the actual setting.

[0163] In the embodiments of this application, the first triplet energy level T1 of the first compound and the second compound is relatively high, which can achieve T1 (first compound) > T1 (second compound) > S1 (fluorescent material). The triplet excitons of the host material have a high efficiency in transferring energy to the triplet excitons of the sensitizer, and then the sensitizer has a high efficiency in transferring energy from the triplet excitons to the singlet excitons of the guest material, thereby improving the luminous efficiency of the light-emitting device.

[0164] Table 1 provides test data for light-emitting devices with different compositions of the light-emitting layer:

[0165] Table 1. Performance test results of the light-emitting devices

[0166]

[0167] H1 is a main material in the related technology, with the following structure: ;

[0168] D1 is a fluorescent material with the following structure: ;

[0169] D2 is another fluorescent material with the following structure: .

[0170] The external quantum efficiency (EQE) and luminescence efficiency in Table 1 are normalized parameters based on data from control group 1.

[0171] The external quantum efficiency is the ratio of the number of emitted photons to the number of injected electron-hole pairs.

[0172] Based on the comparison between control group 1 and experimental groups 1, 2, and 3, compared with the combination of H1 and the second compound, the combination of the first compound as the host material and the second compound as the guest material in this application has higher external quantum efficiency and higher luminescence efficiency.

[0173] Based on the comparison between control group 2 and experimental groups 4 and 5, compared with the combination of H1 and D1, the combination of the first compound as the host material, the second compound as the sensitizer, and D1 or D2 as the fluorescent guest material in this application has higher external quantum efficiency and higher luminescence efficiency.

[0174] Optional, refer to Figure 1 The light-emitting device also includes: hole transport layer 5 and electron transport layer 8;

[0175] Hole transport layer 5 is located between the first electrode 1 and the light-emitting layer 2; electron transport layer 8 is located between the second electrode 3 and the light-emitting layer 2;

[0176] At least one of the hole transport layer 5 and the electron transport layer 8 includes a second compound.

[0177] In an exemplary embodiment, the first electrode 1 can be an anode and the second electrode 3 can be a cathode.

[0178] In this embodiment, the second compound serves as an auxiliary doping material in the hole transport layer 5 or the electron transport layer 8. The doping concentration is not specifically limited in this embodiment and can be set according to actual needs.

[0179] In some embodiments, the second compound serves as an auxiliary dopant material for the hole transport layer 5; in some embodiments, the second compound serves as an auxiliary dopant material for the electron transport layer 8; in some embodiments, the second compound serves as an auxiliary dopant material for both the hole transport layer 5 and the electron transport layer 8.

[0180] It should be noted that the second compound in hole transport layer 5, the second compound in electron transport layer 8, and the second compound in light-emitting layer 2 can be the same or different. This application embodiment does not specifically limit this, and the specific settings are based on actual needs.

[0181] The light-emitting device provided in this application embodiment includes at least one second compound in the first carrier transport layer 5 and the second carrier transport layer 8. The second compound has a stable structure, which improves the quality of the carrier transport layer and extends the lifespan of the light-emitting device.

[0182] Optionally, the LUMO level of the second compound of the electron transport layer is less than or equal to -2.5 eV, where LUMO (Lowest Unoccupied Molecule Orbital) is the lowest orbital with no occupied electrons.

[0183] For example, the LUMO level of the second compound in the electron transport layer can be -2.5 eV, -2.6 eV, -2.7 eV, -2.8 eV, -2.9 eV, or -3.0 eV.

[0184] In this embodiment, on the one hand, the LUMO energy level of the second compound of the electron transport layer is less than or equal to -2.5eV, which can realize the function of electron transport; on the other hand, the T1 energy level of the second compound is relatively high, which can block the transport of holes to a certain extent and improve the efficiency of electron transport.

[0185] In some embodiments, refer to Figure 2 The light-emitting device includes a hole injection layer 4, a hole transport layer 5, an electron blocking layer 6, a light-emitting layer 2, a hole blocking layer 9, an electron transport layer 8, and an electron injection layer 7, which are stacked sequentially on the first electrode 1.

[0186] This application provides a method for fabricating a light-emitting device, the method comprising:

[0187] S101, forming anode 1 on the substrate.

[0188] The substrate described above is a rigid substrate; for example, the substrate can be a glass substrate.

[0189] This application does not specifically limit the method for forming anode 1. For example, the method for forming anode 1 can be vacuum evaporation, for example, in a vacuum of 1×10⁻⁶. -5 Anode 1 is deposited by vapor deposition under Pa conditions.

[0190] In this embodiment of the application, the thickness of the anode 1 in the direction from the substrate to the anode 1 is not limited. For example, the thickness of the anode 1 is in the range of 80nm to 120nm. For example, the thickness of the anode 1 can be 80nm, 90nm, 100nm, 110nm or 120nm.

[0191] In this embodiment of the application, the material of the anode 1 includes a light-transmitting metal oxide, for example, the material of the anode 1 can be indium tin oxide (ITO) or indium zinc oxide (IZO).

[0192] S102, forming hole injection layer 4.

[0193] The embodiments of this application do not specifically limit the method of forming the hole injection layer 4. For example, the method of forming the hole injection layer 4 can be vacuum evaporation.

[0194] In this embodiment, the thickness of the hole injection layer 4 along the direction from the substrate to the anode 1 is not limited. For example, the thickness of the hole injection layer 4 is in the range of 5nm to 15nm. For instance, the thickness of the hole injection layer 4 can be 5nm, 7nm, 9nm, 10nm, 12nm or 15nm.

[0195] S103 forms hole transport layer 5.

[0196] The embodiments of this application do not specifically limit the method of forming the hole transport layer 5. For example, the method of forming the hole transport layer 5 can be vacuum evaporation.

[0197] In this embodiment, the thickness of the hole transport layer 5 along the direction from the substrate to the anode 1 is not specifically limited; for example, the thickness of the hole transport layer 5 is in the range of 40nm to 80nm, such as 40nm, 50nm, 60nm, 70nm or 80nm.

[0198] S104 forms an electron blocking layer 6.

[0199] The embodiments of this application do not specifically limit the method of forming the electron blocking layer 6. For example, the method of forming the electron blocking layer 6 can be vacuum evaporation.

[0200] In this embodiment, the thickness of the electron blocking layer 6 along the direction from the substrate to the anode 1 is not specifically limited; for example, the thickness of the electron blocking layer 6 is in the range of 5nm to 15nm, such as 5nm, 7nm, 9nm, 10nm, 12nm or 15nm.

[0201] S105 forms the light-emitting layer 2.

[0202] In this embodiment, the method for forming the light-emitting layer 2 includes co-evaporation deposition.

[0203] For example, a host material and a guest material are co-deposited on an electron blocking layer 6; the host material includes a first compound and the guest material includes a second compound;

[0204] For example, a host material, a sensitizer, and a guest material are co-deposited on an electron blocking layer 6; the host material includes a first compound, the sensitizer includes a second compound, and the guest material includes a fluorescent material.

[0205] In this embodiment, the thickness of the light-emitting layer 2 along the direction from the substrate to the anode 1 is not specifically limited; for example, the thickness of the light-emitting layer 2 is in the range of 10nm to 40nm, for example, the thickness of the light-emitting layer 2 can be 10nm, 20nm, 15nm, 25nm, 30nm, 35nm or 40nm.

[0206] S106, forming a hole-blocking layer 9.

[0207] The embodiments of this application do not specifically limit the method of forming the hole blocking layer 9. For example, the method of forming the hole blocking layer 9 can be vacuum evaporation.

[0208] In this embodiment, the thickness of the hole blocking layer 9 along the direction from the substrate to the anode 1 is not specifically limited; for example, the thickness of the hole blocking layer 9 is in the range of 5nm to 15nm, such as 5nm, 7nm, 9nm, 10nm, 12nm or 15nm.

[0209] S107 forms electron transport layer 8.

[0210] The embodiments of this application do not specifically limit the method of forming the electron transport layer 8. For example, the method of forming the electron transport layer 8 can be vacuum evaporation.

[0211] In this embodiment, the thickness of the electron transport layer 8 along the direction from the substrate to the anode 1 is not specifically limited; for example, the thickness of the electron transport layer 8 is in the range of 20nm to 50nm, such as 10nm, 25nm, 30nm, 35nm, 40nm or 50nm.

[0212] S108 forms the electron injection layer 7.

[0213] The embodiments of this application do not specifically limit the method of forming the electron injection layer 7. For example, the method of forming the electron injection layer 7 can be vacuum evaporation.

[0214] In this embodiment, the thickness of the electron injection layer 7 along the direction from the substrate to the anode 1 is not specifically limited; for example, the thickness of the electron injection layer 7 ranges from 0.5 nm to 2 nm, such as 0.5 nm, 0.7 nm, 0.9 nm, 1 nm, 1.3 nm, 1.6 nm or 2 nm.

[0215] In this embodiment, the material of the electron injection layer 7 includes metals, metal oxides, or metal fluorides with electron injection properties. For example, the material of the electron injection layer 7 can be lithium fluoride (LiF).

[0216] S109 forms cathode 3.

[0217] The embodiments of this application do not specifically limit the method of forming the cathode 3. For example, the method of forming the cathode 3 can be vacuum evaporation.

[0218] In this application embodiment, the thickness of the cathode 3 in the direction from the substrate to the anode 1 is not specifically limited; for example, the thickness of the cathode 3 is in the range of 60nm to 100nm, for example, the thickness of the cathode 3 can be 60nm, 70nm, 80nm, 90nm, or 100nm.

[0219] In this embodiment of the application, the material of the cathode 3 includes metallic materials and alloys. For example, the material of the cathode 3 can be aluminum (Al).

[0220] The light-emitting device prepared by the method provided in this application has the advantages of high luminous efficiency, long lifespan, and high stability.

[0221] This application provides a display device including any of the light-emitting devices described above.

[0222] The aforementioned display device can be a flexible display device (also known as a flexible screen) or a rigid display device (i.e., a display screen that cannot be bent), and there is no limitation here.

[0223] The aforementioned display device may be an OLED (Organic Light Emitting Diode) display device;

[0224] The display device can also be an LCD (Liquid Crystal Display) display device, wherein the backlight module of the LCD display device may include multiple light-emitting devices arranged in an array.

[0225] For example, the display device includes a display substrate and light-emitting devices. The display substrate includes a plurality of pixel driving circuits arranged in an array, and the light-emitting devices include red light-emitting devices, green light-emitting devices, and blue light-emitting devices arranged in an array. Each pixel driving circuit includes a red sub-pixel driving circuit, a green sub-pixel driving circuit, and a blue sub-pixel driving circuit. The red sub-pixel driving circuit is electrically connected to the red light-emitting device, the green sub-pixel driving circuit is electrically connected to the green light-emitting device, and the blue sub-pixel driving circuit is electrically connected to the blue light-emitting device.

[0226] For example, refer to Figure 3 As shown, the red sub-pixel driving circuit is electrically connected to the red light-emitting device 100, the green sub-pixel driving circuit is electrically connected to the green light-emitting device 200, and the blue sub-pixel driving circuit is electrically connected to the blue light-emitting device 300. (Reference) Figure 3As shown, taking the red sub-pixel driving circuit located at the far left as an example, the specific structure of the red sub-pixel driving circuit includes: a buffer layer 11, an active layer 210, a gate insulating layer 12, a gate metal layer (including a gate 110 and a first electrode 212), an insulating layer 13, an electrode layer (including a second electrode 213), an interlayer dielectric layer 14, a source / drain metal layer (including a source 111 and a drain 112), a planarization layer 15, and a pixel defining layer 302, which are stacked sequentially on the substrate 10. The first electrode 212 and the second electrode 213 are used to form a storage capacitor. The pixel defining layer 302 includes an opening, within which a red light-emitting device 100 is disposed. The anode 1 of the red light-emitting device 100 is electrically connected to the drain 112 of the thin-film transistor. The display substrate also includes a spacer 34 located above the pixel defining layer 302. It should be noted that in this display substrate, spacers may be disposed on part of the pixel defining layer or on all of the pixel defining layers; this is not limited here.

[0227] The red light-emitting device 100 includes an anode 1 and a hole injection layer 4, a hole transport layer 5, an electron blocking layer 6, a red light-emitting layer 113, a hole blocking layer 9, an electron transport layer 8, an electron injection layer 7, and a cathode 3, which are sequentially stacked on the anode 1.

[0228] It should be noted that, Figure 3 The light-emitting layers of the green light-emitting device 200 and the blue light-emitting device 300 shown are made of different materials than the light-emitting layer of the red light-emitting device 100. The light-emitting layer of the green light-emitting device is used to emit green light, the light-emitting layer of the blue light-emitting device is used to emit blue light, and the light-emitting layer of the red light-emitting device is used to emit red light. Furthermore, the electron blocking layers of the green and blue light-emitting devices are also made of different materials than the electron blocking layer of the red light-emitting device. Apart from the light-emitting layer and the electron blocking layer, the other film layers included in the green and blue light-emitting devices are the same as those in the red light-emitting device, and will not be described further here.

[0229] refer to Figure 3 As shown, the display device may also include a first inorganic layer 421, an organic layer 43, and a second inorganic layer 422 covering the light-emitting device. The first inorganic layer 421, the organic layer 43, and the second inorganic layer 422 can serve as an encapsulation layer to protect the light-emitting device and extend its service life.

[0230] The aforementioned display devices can be any product or component with display function, such as televisions, digital cameras, mobile phones, and tablet computers; the aforementioned display devices can also be applied to fields such as identity recognition and medical devices, and products that have been promoted or have good prospects for promotion include security identity authentication, smart door locks, and medical image acquisition.

[0231] The display device provided in this application has advantages such as high luminous efficiency, long lifespan, and high stability.

[0232] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A light-emitting device, characterized in that, include: First electrode and second electrode; At least one light-emitting layer is located between the first electrode and the second electrode; The light-emitting layer includes at least one host material and at least one second component, wherein the host material includes a first compound and the second component includes a second compound; The first compound and the second compound have a first group; The structure of the first group includes Where a represents the number of Z1, b represents the number of Z2, and c represents the number of Z3; a, b, and c are each independently selected from 0 or 1. Z1, Z2 and Z3 respectively include one of boron, phosphorus, nitrogen, substituted or unsubstituted methine and substituted or unsubstituted silyl group; (Z1) a (Z2) b and (Z3) c The total number of nitrogen atoms included is less than or equal to 2; Y includes carbon or silicon; Cy includes one of substituted or unsubstituted C5 to C30 aromatic groups and substituted or unsubstituted C5 to C40 heteroaromatic groups; Where 0.1eV≤T1(first compound)-T1(second compound)≤0.5eV, T1 is the first triplet energy level; The structure of the second compound includes: Wherein, M includes platinum or palladium; at least one of R1, R2, R3 and R4 includes the first group, either substituted or unsubstituted; R1, R2, R3 and R4 each comprise one of the first group (substituted or unsubstituted), aryl, cycloalkyl, cycloalkenyl, heteroaryl, heterocyclic, carbene and n-heterocyclic carbene; A1, A2, A3, and A4 form coordinate or covalent bonds with M, where A1, A2, A3, and A4 respectively include one of carbon, nitrogen, oxygen, sulfur, boron, phosphorus, and silicon. Where e represents the number of X1, f represents the number of X2, and g represents the number of X3; e, f, and g are each independently selected from 0 or 1. X1, X2, or X3 respectively includes one of the following: oxygen, sulfur, thionyloxy group, carbonyl group, substituted or unsubstituted imino group, methylene group, phosphine group, silyl group, boraneyl group, substituted or unsubstituted C1 to C40 straight-chain alkylene group, alkoxy group, thionyloxy group, substituted or unsubstituted C2 to C40 alkenyl group, alkyne group, substituted or unsubstituted C3 to C20 branched alkylene group, branched alkoxy group, branched thionyloxy group, substituted or unsubstituted C3 to C20 cycloalkylene group, cycloalkoxy group, cyclothionyloxy group, substituted or unsubstituted C5 to C60 aryl group, and substituted or unsubstituted C5 to C60 heteroaryl group.

2. The light-emitting device according to claim 1, characterized in that, The first compound further includes a second group, which is linked to the first group; The structure of the second group includes substituted or unsubstituted forms. Wherein, d represents the number of L1, and d is selected from 0 or 1; L1 includes one of the substituted or unsubstituted C6 to C60 aryl groups; L2 and L3 each comprise one of a substituted or unsubstituted C1 to C40 alkyl group and a substituted or unsubstituted C6 to C60 aryl group, respectively.

3. The light-emitting device according to claim 2, characterized in that, structure include structure include Among them, (Ra1) n This indicates that (Ra2) has n identical or different Ra1 substituents. n This indicates that (Ra3) has n identical or different Ra2 substituents. n This indicates that (Ra4) has n identical or different Ra3 substituents. n This indicates that (Ra5) has n identical or different Ra4 substituents. n This indicates that (Ra6) has n identical or different Ra5 substituents. n This indicates that there are n identical or different Ra6 substituents, (Ra7) n This indicates that (Ra8) has n identical or different Ra7 substituents. n This indicates that there are n identical or different Ra8 substituents; (Ra1) n (Ra2) n (Ra3) n and (Ra4) n In this context, n is selected from one of the values ​​0, 1, 2, 3, 4, and 5; (Ra5) n (Ra6) n (Ra7) n and (Ra8) n The 'n' in the equation is selected from one of the following: 0, 1, 2, 3, and 4. Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7, and Ra8 respectively include deuterium, halogen, hydroxyl, nitro, nitrile, substituted or unsubstituted amino, substituted or unsubstituted carboxyl, substituted or unsubstituted silyl, substituted or unsubstituted boronyl, substituted or unsubstituted aldehyde, substituted or unsubstituted phosphohydroxy, substituted or unsubstituted phosphoalkyl, substituted or unsubstituted sulfenic acid, substituted or unsubstituted sulfinic acid, substituted or unsubstituted sulfonic acid, substituted or unsubstituted C1 to C40 straight-chain alkyl, alkoxy, thioalkoxy, substituted or unsubstituted C3 to C20 branched alkylene, branched alkoxy, branched thioalkoxy, and substituted or unsubstituted C3 to C20 cycloalkylene, cycloalkoxy, cyclothioalkoxy.

4. The light-emitting device according to claim 1, characterized in that, The second component includes a guest material, which includes the second compound, which belongs to the phosphorescent material category.

5. The light-emitting device according to claim 1, characterized in that, The light-emitting layer further includes at least one third component; The second component includes a sensitizer, and the third component includes a guest material; The sensitizer includes the second compound, and the guest material includes a fluorescent material.

6. The light-emitting device according to any one of claims 4 to 5, characterized in that, The light-emitting device further includes: a hole transport layer and an electron transport layer; The hole transport layer is located between the first electrode and the light-emitting layer; the electron transport layer is located between the second electrode and the light-emitting layer; At least one of the hole transport layer and the electron transport layer includes the second compound.

7. The light-emitting device according to claim 6, characterized in that, The LUMO energy level of the second compound in the electron transport layer is less than or equal to -2.5 eV, where LUMO is the lowest energy orbital without occupied electrons.

8. The light-emitting device according to claim 4, characterized in that, The emission wavelength range of the second compound is 430 nm to 490 nm.

9. A display device, characterized in that, The light-emitting device includes any one of claims 1 to 8.

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