Organic electroluminescent material, device and preparation method

Abstract

Compositions, devices, and methods of making are disclosed. The composition includes a pre-mixture including first and second host compounds and a fluorescent compound, and a phosphorescent sensitizer. The first host compound has an evaporation temperature T1, the second host compound has an evaporation temperature T2, T1 and T2 both range from 100 DEG C to 400 DEG C, and the absolute value of the difference between T1 and T2 is smaller than or equal to 20 DEG C. The premixture contained in the composition shows high evaporation stability, stable device performance can be obtained when the premixture is applied to the continuous evaporation organic electroluminescent device, meanwhile, the premixture can be used as a single evaporation source in the preparation process of the device, and the cost and complexity of the evaporation process are reduced. In addition, the composition provided by the invention can be used in devices, can obtain more excellent device performance, and has narrow half-peak width, high external quantum efficiency and / or long device life. The invention also discloses a device comprising the composition and a preparation method of the device.

Description

Technical Field

[0001] The present invention relates to organic electronic devices, such as organic electroluminescent devices. In particular, it relates to organic electroluminescent materials used in such devices. More particularly, it relates to a premix comprising three materials and a composition thereof with a phosphorescent sensitizer, a device comprising the composition in a light-emitting layer, and a method for preparing the device. Background Art

[0002] Organic electronic devices include, but are not limited to, the following categories: organic light-emitting diodes (OLEDs), organic field-effect transistors (O-FETs), organic light-emitting transistors (OLETs), organic photovoltaics (OPVs), dye-sensitized solar cells (DSSCs), organic photodetectors, organic photoreceptors, organic field-effect devices (OFQDs), light-emitting electrochemical cells (LECs), organic laser diodes, and organic plasmonic light-emitting devices.

[0003] In 1987, Tang and Van Slyke of Eastman Kodak reported a double-layer organic electroluminescent device that included an arylamine hole transport layer and a tris-8-hydroxyquinoline-aluminum layer as an electron transport layer and a light-emitting layer (Applied Physics Letters, 1987, 51(12):913-915). Once a bias voltage was applied to the device, green light was emitted from the device. This invention laid the foundation for the development of modern organic light-emitting diodes (OLEDs). The most advanced OLEDs can include multiple layers, such as charge injection and transport layers, charge and exciton blocking layers, and one or more light-emitting layers between the cathode and anode. Since OLEDs are self-luminous solid-state devices, they offer great potential for display and lighting applications. In addition, the inherent properties of organic materials, such as their flexibility, can make them very suitable for special applications, such as on flexible substrates.

[0004] OLEDs can be categorized into three different types based on their emission mechanism. The OLED invented by Tang and van Slyke is a fluorescent OLED. It uses only singlet emission. Triplet states generated in the device are wasted through non-radiative decay channels. As a result, the internal quantum efficiency (IQE) of fluorescent OLEDs is only 25%. This limitation has hindered the commercialization of OLEDs. In 1997, Forrest and Thompson reported phosphorescent OLEDs, which use triplet emission from heavy metal complexes as the emitter. This allows for the harvesting of both singlet and triplet states, achieving an IQE of 100%. Due to its high efficiency, the discovery and development of phosphorescent OLEDs directly contributed to the commercialization of active-matrix OLEDs (AMOLEDs). More recently, Adachi achieved high efficiency through thermally activated delayed fluorescence (TADF) of organic compounds. These emitters have a small singlet-triplet gap, enabling excitons to return from the triplet state to the singlet state. In TADF devices, triplet excitons can generate singlet excitons through reverse intersystem crossing, resulting in high IQE.

[0005] OLEDs can also be categorized based on the form of the materials used, into small molecule and polymer OLEDs. A small molecule is any organic or organometallic material that is not a polymer. Small molecules can have large molecular weights as long as they have a precise structure. Dendrimers, with their well-defined structure, are considered small molecules. Polymer OLEDs include conjugated polymers and non-conjugated polymers with pendant luminescent groups. Small molecule OLEDs can become polymer OLEDs if post-polymerization occurs during the manufacturing process.

[0006] Various OLED manufacturing methods exist. Small molecule OLEDs are typically produced by vacuum thermal evaporation (evaporation). Polymer OLEDs are produced using solution methods such as spin coating, inkjet printing, and nozzle printing. Small molecule OLEDs can also be produced using solution methods if the material can be dissolved or dispersed in a solvent.

[0007] The luminescent color of OLEDs can be achieved through the structural design of luminescent materials. OLEDs can include one or more luminescent layers to achieve the desired spectrum. Green, yellow, and red OLEDs, phosphorescent materials have been successfully commercialized. Blue phosphorescent devices still have problems such as blue unsaturation, short device life, and high operating voltage. Commercial full-color OLED displays generally adopt a hybrid strategy, using blue fluorescence and phosphorescent yellow, or red and green. Currently, the efficiency of phosphorescent OLEDs decreases rapidly under high brightness conditions, which remains a problem. In addition, it is expected to have a more saturated luminescent spectrum, higher efficiency, and longer device life.

[0008] The prior art discloses devices and applications in which a phosphorescent sensitizer and a luminescent material are co-doped into a host material in an organic light-emitting layer (EML). However, in practical applications, the introduction of other materials into the organic light-emitting layer generally requires an additional evaporation source, and the evaporation process is very complex and expensive. A desirable approach is to pre-mix multiple materials in the light-emitting layer to form a pre-mixture with high evaporation stability, which is then placed in a single evaporation source. This can reduce the use of evaporation sources and thus reduce the cost and complexity of the evaporation process. However, the co-evaporation of the pre-mixture that can be used as a single evaporation source must be stable, so as to ensure that the device performance of the device prepared by the evaporation pre-mixture is stable. However, when multiple compounds are mixed together to form a pre-mixture, the possible interactions between the compounds will affect the stability of the evaporation film, making it difficult to achieve a stable co-evaporation pre-mixture.

[0009] Research on phosphorescent-sensitized fluorescent devices has reported premixing a fluorescent luminescent material and a single host material (a two-component premix) and then placing them in a single evaporation source. For example, CN116814246A discloses an organic luminescent material comprising a fluorescent guest and a phosphorescent sensitizer and / or a host material, and further discloses an organic electroluminescent device and display device comprising the organic luminescent material. In the device embodiment, this application premixes the fluorescent guest and the single host material and places them in a single evaporation source, while placing the phosphorescent sensitizer in another evaporation source. This solves the problem of requiring three evaporation sources when preparing a three-component luminescent layer, thereby reducing the difficulty and cost of the evaporation process. However, to achieve better device performance, phosphorescence-sensitized fluorescent devices typically require the introduction of two different host materials into the light-emitting layer. This is particularly true for phosphorescence-sensitized TADF devices, which contain four-component materials in their light-emitting layer. To reduce the cost and complexity of the evaporation process, it is desirable to pre-mix three of the components to form a premix with high evaporation stability. However, pre-mixing three components complicates the interactions between the compounds, making it more difficult to create a premix with high evaporation stability. Therefore, simplifying the evaporation process while maintaining device performance when using four-component materials in the light-emitting layer presents a challenge. Summary of the Invention

[0010] The present invention aims to provide a new type of premix and a composition comprising the premix and a phosphorescent sensitizer to solve at least some of the above problems. The premix comprises a first host compound, a second host compound and a fluorescent compound. The first host compound has an evaporation temperature T1, the second host compound has an evaporation temperature T2, T1 and T2 are both 100°C to 400°C, and the absolute value of the difference between T1 and T2 is less than or equal to 20°C. The premix of the present invention exhibits high evaporation stability and can be applied to organic electroluminescent devices produced by continuous evaporation in industrial mass production to obtain stable device performance. At the same time, the premix of the present invention can be used as a single evaporation source in the preparation process of the device, reducing the cost and complexity of the evaporation process. In addition, the composition of the present invention can be used in the light-emitting layer of the device, and compared with ordinary devices, it can obtain better device performance, with a narrow half-width, high external quantum efficiency and / or long device life.

[0011] According to one embodiment of the present invention, a premixture is disclosed, which comprises a first host compound, a second host compound and a fluorescent compound;

[0012] Wherein, the triplet energy levels of the first host compound and the second host compound are both higher than the triplet energy level of the fluorescent compound;

[0013] The first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.;

[0014] The second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.;

[0015] The absolute value of the difference between T1 and T2 is less than or equal to 20°C.

[0016] According to one embodiment of the present invention, a use of a premixture in a sensitizer device is disclosed. The premixture is as described in the above embodiment, and the premixture is co-evaporated with a phosphorescent sensitizer to prepare the sensitizer device.

[0017] According to one embodiment of the present invention, a composition is disclosed, comprising:

[0018] A premix and a phosphorescent sensitizer, wherein the premix comprises a first host compound, a second host compound and a fluorescent compound;

[0019] wherein the triplet energy levels of the first host compound, the second host compound, and the phosphorescence sensitizer are all higher than the triplet energy level of the fluorescent compound;

[0020] wherein the first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.;

[0021] wherein the second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.;

[0022] The absolute value of the difference between T1 and T2 is less than or equal to 20°C.

[0023] According to one embodiment of the present invention, application of the composition in an organic electroluminescent device is disclosed.

[0024] According to one embodiment of the present invention, an organic electroluminescent device is disclosed, comprising:

[0025] anode,

[0026] cathode,

[0027] and an organic layer disposed between the anode and cathode, the organic layer comprising the composition described in the above examples.

[0028] According to one embodiment of the present invention, a method for preparing an organic electroluminescent device is disclosed, wherein the organic electroluminescent device includes an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer includes the composition described in the above embodiment. The preparation method comprises:

[0029] Step 1: providing a substrate and arranging the anode thereon;

[0030] Step 2: pre-mix the first host compound, the second host compound and the fluorescent compound to form the pre-mixture, and place it in the evaporation source 1 of the high vacuum deposition tool; place the phosphorescence sensitizer in the evaporation source 2 of the high vacuum deposition tool; -6 co-evaporating the premixture in the evaporation source 1 and the phosphorescent sensitizer in the evaporation source 2 at a rate of 0.2-2 angstroms / second in a high vacuum deposition tool of 1000 Torr or lower, and co-evaporating the premixture in the evaporation source 1 and the phosphorescent sensitizer in the evaporation source 2 on a surface positioned at a certain distance from the evaporated premixture and phosphorescent sensitizer to form the organic layer,

[0031] wherein the triplet energy levels of the first host compound, the second host compound, and the phosphorescence sensitizer are all higher than the triplet energy level of the fluorescent compound;

[0032] wherein the first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.;

[0033] wherein the second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.;

[0034] The absolute value of the difference between T1 and T2 is less than or equal to 20°C.

[0035] Step 3: Depositing the cathode on the organic layer.

[0036] The present invention aims to provide a novel premixture and a composition containing the same. This novel composition comprises the premixture and a phosphorescent sensitizer, and the premixture comprises a first host compound, a second host compound and a fluorescent compound. The first host compound has an evaporation temperature T1, and the second host compound has an evaporation temperature T2, T1 and T2 are both 100°C to 400°C, and the absolute value of the difference between T1 and T2 is less than or equal to 20°C. The premixture of the present invention exhibits high evaporation stability and can obtain stable device performance when applied to organic electroluminescent devices subjected to continuous evaporation. At the same time, the premixture of the present invention can be used as a single evaporation source in the preparation process of the device, reducing the cost and complexity of the evaporation process. In addition, the composition of the present invention can be used in the light-emitting layer of the device, and compared with ordinary devices, it can obtain better device performance, with a narrow half-width, high external quantum efficiency and / or long device life. In particular, when the fluorescent compound contained in the premix of the present invention is an E-type delayed fluorescent compound, the premix exhibits high evaporation stability and can obtain stable device performance when applied to organic electroluminescent devices produced by continuous evaporation in industrial mass production. It has great potential application value in industrial mass production and can obtain better device performance than ordinary devices, with a narrow half-width, high external quantum efficiency and / or long device life. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a schematic diagram of an organic light-emitting device that may contain the organic electroluminescent device disclosed herein.

[0038] Figure 2 is a schematic diagram of another organic light-emitting device that may contain the organic electroluminescent device disclosed herein.

[0039] Figure 3 Graphs showing emission spectra of devices of Example 1, Comparative Example 1 and Comparative Example 2 after normalization. DETAILED DESCRIPTION

[0040] OLEDs can be manufactured on a variety of substrates, such as glass, plastic, and metal. Figure 1An organic light-emitting device 100 is shown schematically and non-limitingly. The figure is not necessarily drawn to scale, and some layer structures in the figure may be omitted as needed. The device 100 may include a substrate 101, an anode 110, a hole injection layer 120, a hole transport layer 130, an electron blocking layer 140, a light-emitting layer 150, a hole blocking layer 160, an electron transport layer 170, an electron injection layer 180 and a cathode 190. The device 100 can be manufactured by depositing the described layers in sequence. The properties and functions of each layer and exemplary materials are described in more detail in columns 6-10 of U.S. Patent No. 7,279,704 B2, the entire contents of which are incorporated herein by reference.

[0041] There are many more examples of each of these layers. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Patent No. 5,844,363, which is incorporated by reference in its entirety. An example of a p-doped hole transport layer is m-MTDATA doped with F4-TCNQ at a molar ratio of 50:1, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety. An example of a host material is disclosed in U.S. Patent No. 6,303,238 to Thompson et al., which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, incorporated by reference in their entireties, disclose examples of cathodes including composite cathodes having a thin layer of a metal such as Mg:Ag with an overlying transparent, conductive, sputter-deposited ITO layer. The principles and use of barrier layers are described in more detail in U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, incorporated by reference in their entireties. An example of an injection layer is provided in U.S. Patent Application Publication No. 2004 / 0174116, incorporated by reference in its entirety. A description of protective layers can be found in U.S. Patent Application Publication No. 2004 / 0174116, incorporated by reference in its entirety.

[0042] The above layered structures are provided by way of non-limiting examples. The functionality of an OLED can be achieved by combining the various layers described above, or some layers can be omitted entirely. It can also include other layers not explicitly described. Within each layer, a single material or a mixture of multiple materials can be used to achieve optimal performance. Any functional layer can include several sublayers. For example, a light-emitting layer can have two layers of different light-emitting materials to achieve a desired emission spectrum.

[0043] In one embodiment, an OLED can be described as having an "organic layer" disposed between a cathode and an anode. The organic layer can include one or more layers.

[0044] OLED also requires encapsulation layers, such as Figure 2 The organic light emitting device 200 is shown schematically and non-limitingly. Figure 1 The difference is that an encapsulation layer 102 can also be included above cathode 190 to prevent harmful substances from the environment, such as moisture and oxygen. Any material that can provide an encapsulation function can be used as the encapsulation layer, such as glass or an organic-inorganic hybrid layer. The encapsulation layer should be placed directly or indirectly on the outside of the OLED device. Multilayer thin-film encapsulation is described in U.S. Patent No. 7,968,146 B2, the entire contents of which are incorporated herein by reference.

[0045] Devices manufactured according to embodiments of the present invention can be incorporated into various consumer products having one or more electronic component modules (or units) of the device. Some examples of these consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for indoor or outdoor lighting and / or signaling, heads-up displays, fully or partially transparent displays, flexible displays, smartphones, tablet computers, tablet phones, wearable devices, smart watches, laptop computers, digital cameras, camcorders, viewfinders, microdisplays, 3-D displays, vehicle displays, and taillights.

[0046] The materials and structures described herein can also be used in other organic electronic devices listed above.

[0047] As used herein, "top" means farthest from the substrate, while "bottom" means closest to the substrate. When a first layer is described as being "disposed on" a second layer, the first layer is disposed farther from the substrate. Unless it is specified that the first layer is "in contact with" the second layer, other layers may be present between the first and second layers. For example, the cathode may be described as being "disposed on" the anode even if various organic layers are present between the cathode and the anode.

[0048] As used herein, "solution processable" means capable of being dissolved, dispersed, or transported in and / or deposited from a liquid medium in the form of a solution or suspension.

[0049] A ligand may be referred to as "photoactive" when it is believed that the ligand directly contributes to the photoactive properties of the emissive material. A ligand may be referred to as "ancillary" when it is not believed to contribute to the photoactive properties of the emissive material, but the ancillary ligand may modify the properties of the photoactive ligand.

[0050] It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs can exceed the 25% spin-statistical limit through delayed fluorescence. Delayed fluorescence can generally be divided into two types, namely P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is generated by triplet-triplet annihilation (TTA).

[0051] On the other hand, E-type delayed fluorescence does not rely on the collision of two triplets, but relies on the conversion between triplet and singlet excited state. Compounds capable of producing E-type delayed fluorescence need to have a very small single-triplet gap so as to convert between energy states. Thermal energy can activate the transition from triplet back to singlet. This type of delayed fluorescence is also called thermally activated delayed fluorescence (TADF). The notable feature of TADF is that the delayed component increases with increasing temperature. If the reverse intersystem crossing (RISC) rate is fast enough to minimize the non-radiative decay by the triplet, the fraction of backfilling the singlet excited state may reach 75%. The total singlet fraction can be 100%, far exceeding the 25% of the spin statistics of the electrically generated excitons.

[0052] The E-type delayed fluorescence feature can be seen in an exciplex system or a single compound. Without being bound by theory, it is believed that the E-type delayed fluorescence requires the luminescent material to have a small singlet-triplet energy gap (ΔE S-T ). Organic non-metallic donor-acceptor luminescent materials may be able to achieve this. The emission of these materials is usually characterized by donor-acceptor charge transfer (CT) type emission. The spatial separation of the HOMO and LUMO in these donor-acceptor type compounds usually produces a small ΔE S-T These states may include CT states. Typically, donor-acceptor light-emitting materials are constructed by linking an electron donor moiety (eg, an amino group or a carbazole derivative) to an electron acceptor moiety (eg, a six-membered aromatic ring containing N).

[0053] Definition of Substituent Terms

[0054] Halogen or halide - as used herein, includes fluorine, chlorine, bromine and iodine.

[0055] Alkyl - as used herein, includes straight chain and branched chain alkyl groups. The alkyl group may be an alkyl group having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 12 carbon atoms, and more preferably an alkyl group having 1 to 6 carbon atoms. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl, 3-methylpentyl. Among the above, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl and n-hexyl are preferred. In addition, the alkyl group may be optionally substituted.

[0056] Cycloalkyl - as used herein, includes cyclic alkyl groups. Cycloalkyl groups can be cycloalkyl groups having 3 to 20 ring carbon atoms, preferably cycloalkyl groups having 4 to 10 carbon atoms. Examples of cycloalkyl groups include cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4,4-dimethylcyclohexyl, 1-adamantyl, 2-adamantyl, 1-norbornyl, 2-norbornyl, and the like. Of the above, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, and 4,4-dimethylcyclohexyl are preferred. In addition, the cycloalkyl group may be optionally substituted.

[0057] Heteroalkyl - As used herein, a heteroalkyl group comprises one or more carbon atoms in the alkyl chain substituted with a heteroatom selected from the group consisting of nitrogen, oxygen, sulfur, selenium, phosphorus, silicon, germanium, and boron atoms. The heteroalkyl group may be a heteroalkyl group having 1 to 20 carbon atoms, preferably a heteroalkyl group having 1 to 10 carbon atoms, and more preferably a heteroalkyl group having 1 to 6 carbon atoms. The example of heteroalkyl includes methoxymethyl, ethoxymethyl, ethoxyethyl, methylthiomethyl, ethylthiomethyl, ethylthioethyl, methoxymethoxymethyl, ethoxymethoxymethyl, ethoxyethoxyethyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, mercaptomethyl, mercaptoethyl, mercaptopropyl, aminomethyl, aminoethyl, aminopropyl, dimethylaminomethyl, trimethylgermanylmethyl, trimethylgermanylethyl, trimethylgermanylisopropyl, dimethylethylgermanylmethyl, dimethylisopropylgermanylmethyl, tert-butyldimethylgermanylmethyl, triethylgermanylmethyl, triethylgermanylethyl, triisopropylgermanylmethyl, triisopropylgermanylethyl, trimethylsilylmethyl, trimethylsilylethyl, trimethylsilylisopropyl, triisopropylsilylmethyl, triisopropylsilylethyl. In addition, heteroalkyl can be optionally substituted.

[0058] Alkenyl - as used herein, encompasses straight chain, branched chain, and cyclic olefin groups. Alkenyl groups can be alkenyl groups containing 2 to 20 carbon atoms, preferably alkenyl groups having 2 to 10 carbon atoms. Examples of alkenyl groups include ethenyl, propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1,3-butadienyl, 1-methylvinyl, styryl, 2,2-diphenylvinyl, 1,2-diphenylvinyl, 1-methylallyl, 1,1-dimethylallyl, 2-methylallyl, 1-phenylallyl, 2-phenylallyl, 3-phenylallyl, 3,3-diphenylallyl, 1,2-dimethylallyl, 1-phenyl-1-butenyl, 3-phenyl-1-butenyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, cycloheptenyl, cycloheptatrienyl, cyclooctenyl, cyclooctatetraenyl, and norbornenyl. Additionally, alkenyl groups can be optionally substituted.

[0059] Alkynyl - as used herein, encompasses straight chain alkynyl groups. Alkynyl groups can be alkynyl groups comprising 2 to 20 carbon atoms, preferably alkynyl groups having 2 to 10 carbon atoms. Examples of alkynyl groups include ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3,3-dimethyl-1-butynyl, 3-ethyl-3-methyl-1-pentynyl, 3,3-diisopropyl-1-pentynyl, phenylethynyl, phenylpropynyl, etc. Among the above, ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, phenylethynyl, etc. are preferred. In addition, alkynyl groups can be optionally substituted.

[0060] Aryl or aromatic group - As used herein, both non-fused and fused systems are contemplated. The aryl group can be an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenanthren, fluorene, pyrene, Perylene and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene and naphthalene. Examples of non-fused aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p-tolyl, p-(2-phenylpropyl)phenyl, 4'-methylbiphenyl, 4"-tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesityl and m-quaterphenyl. In addition, the aryl group may be optionally substituted.

[0061] Heterocyclic group - as used herein, non-aromatic cyclic groups are contemplated. Non-aromatic heterocyclic groups include saturated heterocyclic groups having 3-20 ring atoms and unsaturated non-aromatic heterocyclic groups having 3-20 ring atoms, wherein at least one ring atom is selected from the group consisting of nitrogen atoms, oxygen atoms, sulfur atoms, selenium atoms, silicon atoms, phosphorus atoms, germanium atoms and boron atoms, and preferred non-aromatic heterocyclic groups are those having 3 to 7 ring atoms, including at least one heteroatom such as nitrogen, oxygen, silicon or sulfur. Examples of non-aromatic heterocyclic groups include oxiranyl, oxetanyl, tetrahydrofuranyl, tetrahydropyranyl, dioxopentanyl, dioxanyl, aziridinyl, dihydropyrrolyl, tetrahydropyrrolyl, piperidinyl, oxazolidinyl, morpholinyl, piperazinyl, oxepinyl, thiepinyl, azepine and tetrahydrothioxyl. In addition, the heterocyclic group may be optionally substituted.

[0062] Heteroaryl - As used herein, non-fused and fused heteroaromatic groups may contain from 1 to 5 heteroatoms, at least one of which is selected from the group consisting of nitrogen, oxygen, sulfur, selenium, silicon, phosphorus, germanium, and boron. Heteroaryl also refers to heteroaryl. The heteroaryl group may have from 3 to 30 carbon atoms, preferably from 3 to 20 carbon atoms, and more preferably from 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indole, carbazole, pyridine, indole, pyrrolopyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, In some embodiments, the heteroaryl group comprises an oxadiazole, an isocyanine ...

[0063] Alkoxy - as used herein, is represented by -O-alkyl, -O-cycloalkyl, -O-heteroalkyl, or -O-heterocyclyl. Examples and preferred examples of alkyl, cycloalkyl, heteroalkyl, and heterocyclyl are the same as those described above. The alkoxy group may be an alkoxy group having 1 to 20 carbon atoms, preferably an alkoxy group having 1 to 6 carbon atoms. Examples of alkoxy groups include methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, tetrahydrofuranyloxy, tetrahydropyranyloxy, methoxypropyloxy, ethoxyethyloxy, methoxymethyloxy, and ethoxymethyloxy. In addition, the alkoxy group may be optionally substituted.

[0064] Aryloxy - As used herein, it is represented by -O-aryl or -O-heteroaryl. Examples and preferred examples of aryl and heteroaryl groups are the same as those described above. The aryloxy group may be an aryloxy group having 6 to 30 carbon atoms, preferably an aryloxy group having 6 to 20 carbon atoms. Examples of the aryloxy group include phenoxy and biphenyloxy. In addition, the aryloxy group may be optionally substituted.

[0065] Aralkyl - as used herein, encompasses aryl-substituted alkyl groups. The aralkyl group may be an aralkyl group having 7 to 30 carbon atoms, preferably an aralkyl group having 7 to 20 carbon atoms, and more preferably an aralkyl group having 7 to 13 carbon atoms. Examples of aralkyl groups include benzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, 2-phenylisopropyl, phenyl tert-butyl, α-naphthylmethyl, 1-α-naphthyl-ethyl, 2-α-naphthylethyl, 1-α-naphthylisopropyl, 2-α-naphthylisopropyl, β-naphthylmethyl, 1-β-naphthyl-ethyl, 2-β-naphthyl-ethyl, 1-β-naphthylisopropyl, 2-β-naphthylisopropyl, p-methylbenzyl, m-methylbenzyl, substituted alkyl.Alkyl group can be substituted alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl, alkyl,

[0066] Alkylsilyl - As used herein, encompasses alkyl-substituted silicon groups. The alkylsilyl group may be an alkylsilyl group having 3 to 20 carbon atoms, preferably an alkylsilyl group having 3 to 10 carbon atoms. Examples of alkylsilyl groups include trimethylsilyl, triethylsilyl, methyldiethylsilyl, ethyldimethylsilyl, tripropylsilyl, tributylsilyl, triisopropylsilyl, methyldiisopropylsilyl, dimethylisopropylsilyl, tri-tert-butylsilyl, triisobutylsilyl, dimethyl-tert-butylsilyl, and methyldi-tert-butylsilyl. Additionally, the alkylsilyl group may be optionally substituted.

[0067] Arylsilyl - As used herein, encompasses silicon groups substituted with at least one aryl group. The arylsilyl group may be one having 6 to 30 carbon atoms, preferably one having 8 to 20 carbon atoms. Examples of arylsilyl groups include triphenylsilyl, phenyldibiphenylsilyl, diphenylbiphenylsilyl, phenyldiethylsilyl, diphenylethylsilyl, phenyldimethylsilyl, diphenylmethylsilyl, phenyldiisopropylsilyl, diphenylisopropylsilyl, diphenylbutylsilyl, diphenylisobutylsilyl, and diphenyltert-butylsilyl. Additionally, the arylsilyl group may be optionally substituted.

[0068] Alkylgermanyl - As used herein, alkyl-substituted germanium groups are encompassed. The alkylgermanyl group can be an alkylgermanyl group having 3 to 20 carbon atoms, preferably an alkylgermanyl group having 3 to 10 carbon atoms. Examples of alkylgermanyl groups include trimethylgermanyl, triethylgermanyl, methyldiethylgermanyl, ethyldimethylgermanyl, tripropylgermanyl, tributylgermanyl, triisopropylgermanyl, methyldiisopropylgermanyl, dimethylisopropylgermanyl, tri-tert-butylgermanyl, triisobutylgermanyl, dimethyl-tert-butylgermanyl, and methyldi-tert-butylgermanyl. Additionally, the alkylgermanyl group can be optionally substituted.

[0069] Arylgermanyl - As used herein, encompasses germanium groups substituted with at least one aryl or heteroaryl group. The arylgermanyl group may be one having 6 to 30 carbon atoms, preferably one having 8 to 20 carbon atoms. Examples of arylgermanyl groups include triphenylgermanyl, phenyldibiphenylgermanyl, diphenylbiphenylgermanyl, phenyldiethylgermanyl, diphenylethylgermanyl, phenyldimethylgermanyl, diphenylmethylgermanyl, phenyldiisopropylgermanyl, diphenylisopropylgermanyl, diphenylbutylgermanyl, diphenylisobutylgermanyl, and diphenyltert-butylgermanyl. Additionally, the arylgermanyl group may be optionally substituted.

[0070] The term "aza" in azadibenzofuran, azadibenzothiophene, etc., means that one or more CH groups in the corresponding aromatic moiety are replaced by a nitrogen atom. For example, azatriphenylene includes dibenzo[f,h]quinoxaline, dibenzo[f,h]quinoline, and other analogs having two or more nitrogen atoms in the ring system. Other nitrogen analogs of the above-mentioned aza derivatives will readily occur to one of ordinary skill in the art, and all such analogs are intended to be included within the terminology described herein.

[0071] In the present disclosure, unless otherwise defined, when any one term in the group consisting of substituted alkyl, substituted cycloalkyl, substituted heteroalkyl, substituted heterocyclyl, substituted aralkyl, substituted alkoxy, substituted aryloxy, substituted alkenyl, substituted alkynyl, substituted aryl, substituted heteroaryl, substituted alkylsilyl, substituted arylsilyl, substituted alkylgermanyl, substituted arylgermanyl, substituted amino, substituted acyl, substituted carbonyl, substituted carboxylic acid, Substituted ester groups, substituted sulfinyl groups, substituted sulfonyl groups, substituted phosphino groups refer to any one of alkyl groups, cycloalkyl groups, heteroalkyl groups, heterocyclic groups, aralkyl groups, alkoxy groups, aryloxy groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, alkylsilyl groups, arylsilyl groups, alkylgermanyl groups, arylgermanyl groups, amino groups, acyl groups, carbonyl groups, carboxyl groups, ester groups, sulfinyl groups, sulfonyl groups and phosphino groups, which may be substituted by one or more of deuterium, halogen groups, unsubstituted alkyl groups having 1 to 20 carbon atoms, unsubstituted alkyl groups having 1 to 20 carbon atoms, cycloalkyl groups having 3 to 20 ring carbon atoms, unsubstituted heteroalkyl groups having 1 to 20 ring carbon atoms, unsubstituted heterocyclyl groups having 3 to 20 ring carbon atoms, unsubstituted aralkyl groups having 7 to 30 carbon atoms, unsubstituted alkoxy groups having 1 to 20 carbon atoms, unsubstituted aryloxy groups having 6 to 30 carbon atoms, unsubstituted alkenyl groups having 2 to 20 carbon atoms, unsubstituted alkynyl groups having 2 to 20 carbon atoms, unsubstituted aryl groups having 6 to 30 carbon atoms , unsubstituted heteroaryl having 3 to 30 carbon atoms, unsubstituted alkylsilyl having 3 to 20 carbon atoms, unsubstituted arylsilyl having 6 to 20 carbon atoms, unsubstituted alkylgermanyl having 3 to 20 carbon atoms, unsubstituted arylgermanyl having 6 to 20 carbon atoms, unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphino and combinations thereof.

[0072] It should be understood that when describing a molecular fragment as a substituent or otherwise attached to another moiety, its name can be written according to whether it is a fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuranyl) or according to whether it is an entire molecule (e.g., benzene, naphthalene, dibenzofuran). As used herein, these different ways of designating a substituent or attaching a fragment are considered equivalent.

[0073] In the compounds described herein, hydrogen atoms may be partially or completely replaced by deuterium. Other atoms such as carbon and nitrogen may also be replaced by their other stable isotopes. The replacement of other stable isotopes in compounds may be preferred because it enhances device efficiency and stability.

[0074] In the compounds described herein, polysubstitution refers to a range including disubstitution up to the maximum number of available substitutions. When a substituent in a compound described herein represents polysubstitution (including disubstitution, trisubstitution, tetrasubstitution, etc.), it means that the substituent can be present at multiple available substitution positions on its connected structure, and the substituents present at multiple available substitution positions can have the same structure or different structures.

[0075] In the compounds mentioned in the present disclosure, unless clearly defined, such as adjacent substituents can be optionally connected to form a ring, otherwise adjacent substituents in the compound cannot be connected to form a ring. In the compounds mentioned in the present disclosure, adjacent substituents can be optionally connected to form a ring, including the situation where adjacent substituents can be connected to form a ring, and also including the situation where adjacent substituents are not connected to form a ring. When adjacent substituents can be optionally connected to form a ring, the formed ring can be a monocyclic or polycyclic ring (including spirocyclic, bridged ring, condensed ring, etc.), as well as an alicyclic, heteroalicyclic, aromatic or heteroaromatic ring. In this statement, adjacent substituents can refer to substituents bonded to the same atom, substituents bonded to carbon atoms directly bonded to each other, or substituents bonded to carbon atoms further away. Preferably, adjacent substituents refer to substituents bonded to the same carbon atom and substituents bonded to carbon atoms directly bonded to each other.

[0076] The statement that adjacent substituents can optionally be linked to form a ring is also intended to be taken to mean that two substituents bonded to the same carbon atom are linked to each other by a chemical bond to form a ring, as can be exemplified by the following formula:

[0077]

[0078] The statement that adjacent substituents can optionally be linked to form a ring is also intended to be taken to mean that two substituents bonded to carbon atoms directly bonded to each other are linked to each other via a chemical bond to form a ring, as can be exemplified by the following formula:

[0079]

[0080] The statement that adjacent substituents can optionally be linked to form a ring is also intended to be taken to mean that two substituents bonded to further distant carbon atoms are linked to each other by a chemical bond to form a ring, as can be exemplified by the following formula:

[0081]

[0082] Furthermore, the statement that adjacent substituents can optionally be linked to form a ring is also intended to mean that, in the case where one of the two adjacent substituents represents hydrogen, the second substituent is bonded to the position to which the hydrogen atom is bonded, thereby forming a ring. This is exemplified by the following formula:

[0083]

[0084] According to one embodiment of the present invention, a premixture is disclosed, which comprises a first host compound, a second host compound and a fluorescent compound;

[0085] Wherein, the triplet energy levels of the first host compound and the second host compound are both higher than the triplet energy level of the fluorescent compound;

[0086] The first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.;

[0087] The second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.;

[0088] The absolute value of the difference between T1 and T2 is less than or equal to 20°C.

[0089] According to one embodiment of the present invention, a composition is disclosed, comprising:

[0090] A premix and a phosphorescent sensitizer, wherein the premix comprises a first host compound, a second host compound and a fluorescent compound;

[0091] wherein the triplet energy levels of the first host compound, the second host compound, and the phosphorescence sensitizer are all higher than the triplet energy level of the fluorescent compound;

[0092] wherein the first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.;

[0093] wherein the second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.;

[0094] The absolute value of the difference between T1 and T2 is less than or equal to 20°C.

[0095] According to one embodiment of the present invention, the T1 is 150°C to 350°C, and the T2 is 150°C to 350°C.

[0096] According to one embodiment of the present invention, the temperature T1 is 200°C to 350°C, and the temperature T2 is 200°C to 350°C.

[0097] According to an embodiment of the present invention, the fluorescent compound has an evaporation temperature T3, and T3 is 150°C to 400°C.

[0098] According to one embodiment of the present invention, the fluorescent compound is a P-type delayed fluorescent compound.

[0099] According to one embodiment of the present invention, the fluorescent compound is an E-type delayed fluorescence compound.

[0100] According to an embodiment of the present invention, the fluorescent compound has an evaporation temperature T3, and T3 is 150°C to 350°C.

[0101] According to an embodiment of the present invention, the fluorescent compound has an evaporation temperature T3, and T3 is 180°C to 350°C.

[0102] According to an embodiment of the present invention, the absolute value of the difference between T1 and T2 is less than or equal to 10°C.

[0103] According to an embodiment of the present invention, the absolute value of the difference between T1 and T2 is less than or equal to 5°C.

[0104] According to one embodiment of the present invention, the absolute value of the difference between T3 and T1 or T3 and T2 is less than or equal to 80°C.

[0105] According to one embodiment of the present invention, the absolute value of the difference between T3 and T1 or T3 and T2 is less than or equal to 70°C.

[0106] According to one embodiment of the present invention, the absolute value of the difference between T3 and T1 or T3 and T2 is less than or equal to 60°C.

[0107] According to one embodiment of the present invention, the absolute value of the difference between T3 and T1 or T3 and T2 is less than or equal to 50°C.

[0108] According to one embodiment of the present invention, the absolute value of the difference between T3 and T1 or T3 and T2 is less than or equal to 40°C.

[0109] According to one embodiment of the present invention, the absolute value of the difference between T3 and T1 or T3 and T2 is less than or equal to 30°C.

[0110] According to one embodiment of the present invention, the absolute value of the difference between T3 and T1 or T3 and T2 is less than or equal to 20°C.

[0111] According to one embodiment of the present invention, the thermally activated delayed fluorescence compound (E-type delayed fluorescence compound) has a structure represented by Formula 1:

[0112]

[0113] In formula 1,

[0114] Ring A, Ring B, Ring C, Ring D, and Ring E are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms or an unsaturated heterocyclic ring having 3 to 30 carbon atoms;

[0115] Y1, E1 and E2 are each independently selected from B, N, P, P=O, P=S, As, As=O, As=S, SiR' or GeR';

[0116] T1 to T 10 Each independently selected from C, CR z or N;

[0117] L1, L2, L3, L4 are each selected from the group consisting of a single bond, O, S, Se, BR v or NR v ;

[0118] a, b, c, d, e are each independently selected from 0 or 1;

[0119] R z Each occurrence of the same or different means mono-, poly- or no-substitution;

[0120] R v , R z and R', at each occurrence, is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkyl having 2 to 30 carbon atoms, -alkynyl groups having 20 to 30 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amino groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, -BR"R", and combinations thereof;

[0121] R" is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0122] Adjacent substituent R v , R z , R' and R" can be optionally linked to form a ring.

[0123] In this embodiment, "a, b, c, d, and e are each independently selected from 0 or 1" is intended to indicate the presence or absence of L1, L2, L3, L4, and Y1, corresponding to a, b, c, d, and e. For example, when a is 1, L1 is present, and T1 and T2 are connected via L1; when a is 0, L1 is absent, and T1 and T2 are not connected; when b, c, and d are each independently selected from 0 or 1, the situation is similar to a. When e is 1, Y1 is present, and Ring A is connected to T8 on Ring B and T7 on Ring C via Y1; when e is 0, Y1 is absent, and Ring A, Ring B, and Ring C are not connected.

[0124] In this context, “the adjacent substituent R v , R z , R' and R" can optionally be linked to form a ring, which is intended to indicate adjacent substituent groups, for example, two substituents R z Between two substituents R", between substituents R z and R v Between, the substituent R z and R', and the substituent R z Between R and R", any one or more of these adjacent substituent groups can be connected to form a ring. Obviously, these adjacent substituent groups can also not be connected to form a ring.

[0125] Herein, the "unsaturated carbocycle" includes an aromatic unsaturated carbocycle (aromatic ring) and a non-aromatic unsaturated carbocycle, and the "unsaturated heterocycle" includes an aromatic unsaturated heterocycle (heteroaromatic ring) and a non-aromatic unsaturated heterocycle.

[0126] According to one embodiment of the present invention, the ring A, ring B, ring C, ring D and ring E are each independently selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6-30 carbon atoms or a heteroaromatic ring having 3-30 carbon atoms.

[0127] According to one embodiment of the present invention, the ring A, ring B, ring C, ring D and ring E are each independently selected from a benzene ring, a pyridine ring, a naphthalene ring, a phenanthrene ring, an anthracene ring, an indene ring, a fluorene ring, an indole ring, a carbazole ring, a benzofuran ring, a dibenzofuran ring, a benzosilole ring, a dibenzosilole ring, a benzothiophene ring, a dibenzothiophene ring, a dibenzoselenophene ring, a cyclopentadiene ring, a furan ring, a thiophene ring, or a silole ring.

[0128] According to one embodiment of the present invention, the ring A, ring B, ring C, ring D and ring E are selected from benzene rings.

[0129] According to one embodiment of the present invention, in Formula 1, the e is 1, the Y1 is independently selected from B, P=O or P=S, and the E1 and E2 are independently selected from N or P.

[0130] According to one embodiment of the present invention, in Formula 1, the e is 1, the Y1 is selected from B, and the E1 and E2 are selected from N.

[0131] According to one embodiment of the present invention, in Formula 1, e is 1, a is 0, b is 0, c is 0, and d is 0.

[0132] According to one embodiment of the present invention, in Formula 1, e is 1, a is 1, b is 0, c is 0, and d is 1.

[0133] According to one embodiment of the present invention, in Formula 1, e is 1, a is 0, b is 1, c is 0, and d is 1.

[0134] According to one embodiment of the present invention, in Formula 1, the e is 0, and the E1 and E2 are each independently selected from B or N.

[0135] According to one embodiment of the present invention, in Formula 1, the e is 0, and the E1 and E2 are selected from B.

[0136] According to one embodiment of the present invention, in Formula 1, e is 0, a is 1, b is 1, c is 1, and d is 1.

[0137] According to one embodiment of the present invention, the thermally activated delayed fluorescent compound has a structure represented by one of Formula 1-1 to Formula 1-4:

[0138]

[0139] in,

[0140] a, b, c, d, e, and f are each independently selected from 0 or 1;

[0141] E1 and E2 are each independently selected from B or N;

[0142] L1, L2, L3, L4 are each the same or different and are selected from a single bond, O, S, BR v or NR v ;

[0143] L5, L6 are each identically or differently selected from a single bond, O, S or NR v ;

[0144] R z Each occurrence of the same or different means mono-, poly- or no-substitution;

[0145] R v , R z Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkyl having 2 to 2 alkynyl groups having 0 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amino groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, -BR"R", and combinations thereof;

[0146] R" is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0147] Adjacent substituent R v , R z and R" can be optionally linked to form a ring.

[0148] In this context, “the adjacent substituent R v , R z and R"can optionally be linked to form a ring", is intended to mean two adjacent substituents R on the same ring z They can be connected to form an unsaturated carbon ring or an unsaturated heterocyclic ring containing one or more of O, S, Se, Si, Ge, and P. Two substituents R" can be connected to form a ring. The substituent R z and R v can be connected to form a ring, and the substituent R z and R" can be connected to form a ring. Obviously, two adjacent substituents R on the same ring z They may not be connected to form a ring, and two substituents R" may not be connected to form a ring. z and R v They may not be connected to form a ring, and the substituent R z and R" may not be connected to form a ring.

[0149] According to one embodiment of the present invention, in Formula 1-1, a is 0, b is 0, c is 0, and d is 0.

[0150] According to one embodiment of the present invention, in Formula 1-1, a+b+c+d is greater than or equal to 1.

[0151] According to one embodiment of the present invention, in Formula 1-1, a is 1, b is 0, c is 0, and d is 1.

[0152] According to one embodiment of the present invention, in Formula 1-1, a is 0, b is 1, c is 0, and d is 1.

[0153] According to one embodiment of the present invention, in Formula 1, Formula 1-1 and Formula 1-2, wherein L1, L2, L3, L4 appear each time and are the same or different and are selected from single bond, O, BR v or NR v .

[0154] According to one embodiment of the present invention, in Formula 1-1, L1, L2, L3, and L4 are selected from single bonds.

[0155] According to one embodiment of the present invention, in Formula 1-2, L1, L2, L3, L4 are selected from O or NR v .

[0156] According to one embodiment of the present invention, in Formula 1-2, E1 and E2 are each independently selected from B.

[0157] According to one embodiment of the present invention, in Formula 1-3, a is 1, and b is 1.

[0158] According to one embodiment of the present invention, in Formula 1-3, L1 and L4 are selected from NR v .

[0159] According to one embodiment of the present invention, in Formula 1-4, a is 1, b is 1, c is 0, d is 0, e is 1, and f is 1.

[0160] According to one embodiment of the present invention, in Formula 1-4, a is 0, b is 1, c is 1, d is 1, e is 1, and f is 0.

[0161] According to one embodiment of the present invention, in Formula 1-4, L1, L2, L3, L4, L5, L6 are selected from single bonds, O or NR v .

[0162] According to one embodiment of the present invention, the thermally activated delayed fluorescent compound has a structure represented by Formula 1-1-1, Formula 1-1-2, Formula 1-1-3, Formula 1-1-4, Formula 1-1-5, Formula 1-1-6 or Formula 1-1-7:

[0163]

[0164]

[0165] R z Each occurrence of the same or different means mono-, poly- or no-substitution;

[0166] R z each occurrence is identically or differently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, -BR"R", and combinations thereof;

[0167] R" is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0168] Adjacent substituent R z Can optionally be linked to form a ring.

[0169] According to one embodiment of the present invention, wherein the R z Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted heterocyclyl having 3-20 ring atoms, substituted or unsubstituted aryl having 6-30 carbon atoms, substituted or unsubstituted heteroaryl having 3-30 carbon atoms, substituted or unsubstituted alkylsilyl having 3-20 carbon atoms, substituted or unsubstituted arylsilyl having 6-20 carbon atoms, substituted or unsubstituted amino having 0-20 carbon atoms, cyano, and combinations thereof.

[0170] According to one embodiment of the present invention, wherein the R z Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, cyano, and combinations thereof.

[0171] According to one embodiment of the present invention, wherein the R z Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, fluorine, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, tert-butyl, deuterated tert-butyl, cyclopentyl, cyclohexyl, phenyl, trimethylsilyl, carbazolyl, indolyl, benzofuranyl, dibenzofuranyl, benzothioyl, dibenzothioyl, benzothiophenyl, dibenzothiophenyl, dibenzoselenophene, and combinations thereof.

[0172] According to one embodiment of the present invention, the thermally activated delayed fluorescent compound contains multiple R z , the multiple R z At least one (e.g., one, two, three, or four) of the moieties is selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, and combinations thereof.

[0173] According to one embodiment of the present invention, the substituents R on the rings A, B, C, D and E z Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1-20 carbon atoms, substituted or unsubstituted heterocyclyl having 3-20 ring atoms, substituted or unsubstituted aryl having 6-30 carbon atoms, substituted or unsubstituted heteroaryl having 3-30 carbon atoms, substituted or unsubstituted alkylsilyl having 3-20 carbon atoms, substituted or unsubstituted arylsilyl having 6-20 carbon atoms, substituted or unsubstituted amino having 0-20 carbon atoms, cyano, and combinations thereof.

[0174] According to one embodiment of the present invention, the fluorescent compound is selected from the group consisting of compound BN-BD-1 to compound BN-BD-53, compound BN-RD-1 to compound BN-RD-22, compound BN-GD-1 to compound BN-GD-63 and compound FD-1-1 to compound FD-1-53, and the specific structures of compound BN-BD-1 to compound BN-BD-53, compound BN-RD-1 to compound BN-RD-22, compound BN-GD-1 to compound BN-GD-51, compound BN-GD-53 to compound BN-GD-63 and compound FD-1-1 to compound FD-1-53 are described in claim 9.

[0175] According to one embodiment of the present invention, the hydrogen in compounds BN-BD-1 to BN-BD-53, compounds BN-RD-1 to BN-RD-22, compounds BN-GD-1 to BN-GD-51, compounds BN-GD-53 to BN-GD-63 and compounds FD-1-1 to FD-1-53 can be partially or completely replaced by deuterium.

[0176] According to one embodiment of the present invention, the maximum emission wavelength λ in the photoluminescence spectrum of the fluorescent compound max-PL It is 450nm~500nm.

[0177] According to one embodiment of the present invention, the maximum emission wavelength λ in the photoluminescence spectrum of the fluorescent compound max-PL It is 450nm~470nm.

[0178] According to one embodiment of the present invention, the maximum emission wavelength λ in the photoluminescence spectrum of the fluorescent compound max-PL It is 455nm~465nm.

[0179] According to one embodiment of the present invention, the maximum emission wavelength λ in the photoluminescence spectrum of the fluorescent compound max-PL It is 520nm~650nm.

[0180] According to one embodiment of the present invention, the maximum emission wavelength λ in the photoluminescence spectrum of the fluorescent compound max-PL It is 520nm~630nm.

[0181] According to one embodiment of the present invention, the maximum emission wavelength λ in the photoluminescence spectrum of the fluorescent compound max-PL It is 520nm~580nm.

[0182] According to one embodiment of the present invention, the full width at half maximum (FWHM) of the photoluminescence spectrum of the fluorescent compound is PL Less than or equal to 45nm.

[0183] According to one embodiment of the present invention, the full width at half maximum (FWHM) of the photoluminescence spectrum of the fluorescent compound is PL Less than or equal to 35nm.

[0184] According to one embodiment of the present invention, the full width at half maximum (FWHM) of the photoluminescence spectrum of the fluorescent compound is PL Less than or equal to 30nm.

[0185] According to one embodiment of the present invention, the full width at half maximum (FWHM) of the photoluminescence spectrum of the fluorescent compound is PL Less than or equal to 25nm.

[0186] According to one embodiment of the present invention, the full width at half maximum (FWHM) of the photoluminescence spectrum of the fluorescent compound is PL Less than or equal to 20nm.

[0187] According to one embodiment of the present invention, the absolute value of the difference between the triplet energy levels of the phosphorescent sensitizer and the fluorescent compound is less than or equal to 20 nm.

[0188] In the present invention, the maximum emission wavelength of the photoluminescence spectrum λ max-PL and full width at half maximum (FWHM) PL The test method is as follows:

[0189] The photoluminescence spectrum (PL) data of the test compound was measured using a Lingguang F98 fluorescence spectrophotometer produced by Shanghai Lingguang Technology Co., Ltd. The test compound was dissolved in toluene solvent to prepare 1×10 -6 mol / L concentration of the solution, nitrogen is passed through the prepared test solution to remove oxygen for 5 minutes, the test solution is placed in a quartz sample tube, and the emission spectrum is measured at room temperature (298K) using light with the maximum absorption wavelength of the test compound. The emission spectrum has a maximum emission wavelength λ max-PL and full width at half maximum (FWHM) PL (i.e. the peak width at half the maximum emission peak height, the distance between the two points where a straight line parallel to the horizontal axis passes through the midpoint of the peak height and intersects the two sides of the peak).

[0190] As an example, the maximum emission wavelength λ of the photoluminescence spectrum of the following thermally activated delayed fluorescent compound was measured by the above method: max-PL and full width at half maximum (FWHM) PL The specific results are shown in Table 1:

[0191] Table 1 Maximum emission wavelength and full width at half maximum of photoluminescence spectra of compounds

[0192] Compound number <![CDATA[λ max-PL (nm)]]> <![CDATA[FWHM- PL (nm)]]> BN-BD-1 453 25.8 BN-BD-2 459 25.3 BN-BD-20 465 24.4 BN-BD-34 460 27.4 BN-GD-12 545 30.31 .

[0193] Determination of triplet energy levels:

[0194] Herein, the triplet energy level (T1) of the first host compound, the second host compound, the fluorescent compound, and the blue phosphorescent sensitizer is measured at ultra-low temperature using the characteristics of the long-lived triplet exciton. Specifically, the compound to be tested is dissolved in 2-methyltetrahydrofuran solvent to prepare 10 -5A solution of the test compound with a concentration of M was placed in a quartz tube, placed in a Dewar flask, and cooled to 77K. The solution was then illuminated with a light source at the test compound's maximum absorption wavelength to measure the phosphorescence spectrum. The spectra were measured using a model F98 spectrophotometer manufactured by Shanghai Lingguang Technology Co., Ltd.

[0195] The phosphorescence spectrum has a vertical axis representing phosphorescence intensity and a horizontal axis representing wavelength. The triplet energy of the test compound is calculated by taking the minimum value λ1 (nm) relative to the short-wavelength peak of the phosphorescence spectrum and substituting this wavelength into the following conversion formula F1.

[0196] Conversion formula F1: T1 (eV) = 1240 / λ1.

[0197] In this paper, the test method of the triplet energy level (T1) of the red phosphorescent sensitizer and the green phosphorescent sensitizer is as follows: the compound to be tested is dissolved in toluene solvent to prepare 1×10 -6 mol / L concentration of the solution, nitrogen was passed through the prepared test solution to remove oxygen for 5 minutes, the test solution was placed in a quartz sample tube and excited with light of the maximum absorption wavelength of the test compound at room temperature (298K) and its emission spectrum was measured. The spectrum was measured using a spectrophotometer model F98 produced by Shanghai Lingguang Technology Co., Ltd. The maximum emission wavelength λ max (nm) is substituted into the above conversion formula F1 to calculate the triplet energy of the test compound.

[0198] The triplet energy levels T1 (eV) of the following compounds were determined by the above method. The specific results are shown in Table 2-1 and Table 2-2.

[0199] Table 2-1 Triplet states of compounds

[0200] Compound number <![CDATA[T1(eV)]]> P-22 2.96 N-1-15 2.89 Pt27 2.70 Pt11 2.69 BN-BD-1 2.66 BN-BD-2 2.49 BN-BD-20 2.46 BN-BD-34 2.62

[0201] It can be seen from the above results in Table 2-1 that for blue light materials, the triplet energy levels of the first host compound, the second host compound and the phosphorescent sensitizer are all higher than that of the fluorescent compound. Therefore, the first host compound, the second host compound, the phosphorescent sensitizer and the fluorescent compound can be well matched to achieve luminescence of the fluorescent compound.

[0202] Table 2-2 Triplet states of compounds

[0203] Compound number <![CDATA[T1(eV)]]> PH-24 2.70 NH-144 2.53 PH-1 2.71 NH-45 2.60 PH-51 2.70 NH-147 2.54 GD100 2.34 BN-GD-12 2.30

[0204] It can be seen from the above results in Table 2-2 that for green light materials, the triplet energy levels of the first host compound, the second host compound and the phosphorescent sensitizer are all higher than that of the fluorescent compound. Therefore, the first host compound, the second host compound, the phosphorescent sensitizer and the fluorescent compound can be well matched to achieve luminescence of the fluorescent compound.

[0205] According to one embodiment of the present invention, the phosphorescence sensitizer has M(L a ) m (L b ) n (L c ) q The general formula of

[0206] The M is selected from metals with a relative atomic mass greater than 40; preferably, the metal M is selected from the group consisting of Cu, Ag, Au, Zn, Ru, Rh, Pd, Os, Ir and Pt;

[0207] Ligand L a 、L b and L c are respectively the first ligand, the second ligand and the third ligand coordinated with the metal M, the ligand L a 、L b and L c Can be the same or different;

[0208] Ligand L a 、L b and L c can optionally be linked to form a multidentate ligand; for example, L a 、L b and L c Any two of them can be connected to form a tetradentate ligand; for example, L a 、L b and L c can be linked to each other to form a hexadentate ligand; or for example, L a 、L b and L c None of them are connected and thus no multidentate ligand is formed;

[0209] m is 1, 2 or 3; n is 0, 1 or 2; q is 0, 1 or 2; the sum of m, n, q is equal to the oxidation state of metal M; when m is greater than or equal to 2, multiple L a Can be the same or different; when n is 2, the two L b Can be the same or different; when q is 2, the two L c Can be the same or different;

[0210] Ligand L a It has the structure shown in Formula 2:

[0211]

[0212] Ring F and Ring G are identical or different at each occurrence and are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 1 to 30 carbon atoms, or a combination thereof;

[0213] X1 and X2 are each selected, identically or differently, from C or N;

[0214] K1 and K2 are each independently selected from a single bond, O or S;

[0215] A1 is selected from single bond, O, S, Se, (SiR q R q ) y , PR q ,NR q , (CR q R q ) y , a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof; y is the same or different when each occurs and is selected from 1, 2, 3, 4 or 5;

[0216] R f and R g Each occurrence of the same or different means mono-, poly- or no-substitution;

[0217] R f and R g Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0218] Adjacent substituent R f and R g can optionally be linked to form a ring;

[0219] Ligand L b and Lc Each occurrence of is the same or different and is selected from monoanionic bidentate ligands.

[0220] In this embodiment, "the adjacent substituent R f and R g "can optionally be linked to form a ring" is intended to mean that adjacent substituent groups, for example, two substituents R f Between the two substituents R g Between, and R f and R g Any one or more of these substituent groups may be connected to form a ring. Obviously, none of these substituent groups may be connected to form a ring.

[0221] According to one embodiment of the present invention, wherein the L b and L c Each occurrence is identically or differently selected from the group consisting of:

[0222]

[0223]

[0224] in,

[0225] R a and R b Each occurrence is identical or different and represents mono-, poly-, or unsubstituted;

[0226] X b Each occurrence is identical or different and is selected from the group consisting of: O, S, Se, NR N1 and CR C1 R C2 ;

[0227] X c and X d Each occurrence is identically or differently selected from the group consisting of: O, S, Se and NR N2 ;

[0228] R a , R b , R c , R N1 , R N2 , R C1 and R C2Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0229] Adjacent substituent R a , R b , R c , R N1 , R N2 , R C1 and R C2 Can optionally be linked to form a ring.

[0230] In this embodiment, "the adjacent substituent R a , R b , R c , R N1 , R N2 , R C1 and R C2 "can optionally be linked to form a ring" is intended to mean that adjacent substituent groups, for example, two substituents R a Between the two substituents R b Between, the substituent R a and R b Between, the substituent R a and R c Between, the substituent R b and R c Between, the substituent R a and R N1 Between, the substituent R b and R N1 Between, the substituent R a and R C1 Between, the substituent Ra and R C2 Between, the substituent R b and R C1 Between, the substituent R b and R C2 Between, and R C1 and R C2 Between, the substituent R a and R N2 Between, the substituent R b and R N2 Any one or more of these substituent groups may be linked to form a ring. For example, The adjacent substituent R a , R b Can optionally be linked to form rings, which may form one or more of the following structures including but not limited to:

[0231]

[0232] Wherein, W' is selected from O, S, Se, NR w ' or CR w 'R w '; wherein said R w ', R a ', R b 'The definition of R a Obviously, these substituents may not be connected to form a ring.

[0233] According to one embodiment of the present invention, the ligand L a Having a structure represented by Formula 2-1 or Formula 2-2:

[0234]

[0235] In formula 2-1, ring F1 is selected from an unsaturated heterocyclic ring having 1 to 30 carbon atoms;

[0236] In formula 2-2, ring F2 and ring F3 are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof;

[0237] Ring F2 and ring F3 are fused via H1 and H2;

[0238] X1 and X2 are each independently selected from C or N, and X1 and X2 are different;

[0239] H1 and H2 are each identically or differently selected from C or N;

[0240] K1 and K2 are each independently selected from a single bond, O or S;

[0241] G is selected from CR in the same or different way each time it occurs g or N;

[0242] R f1 , R f2 and R f3 Each occurrence represents identically or differently monosubstituted, polysubstituted or unsubstituted;

[0243] R, R g , R f1 , R f2 and R f3 Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0244] Adjacent substituents R, R g , R f1 , R f2 and R f3 Can optionally be linked to form a ring.

[0245] In this embodiment, "adjacent substituents R, R g , R f1 , R f2 and R f3 "can optionally be linked to form a ring" is intended to mean that adjacent substituent groups, for example, two substituents R g Between the two substituents R f1 Between the two substituents R f2 Between the two substituents R f3Between the substituents R and R f1 Between, and the substituent R f2 and R f3 Any one or more of these substituent groups may be connected to form a ring. Obviously, none of these substituent groups may be connected to form a ring.

[0246] According to one embodiment of the present invention, the phosphorescence sensitizer has a structure represented by Formula 21:

[0247]

[0248] In formula 21,

[0249] Ring F, Ring G, Ring H and Ring I are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 1 to 30 carbon atoms, or a combination thereof;

[0250] f is selected from 0 or 1;

[0251] A1-A4 are selected, at each occurrence, identically or differently, from a single bond, O, S, Se, (SiR q R q ) y , PR q ,NR q , (CR q R q ) y , a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof; y is the same or different when each occurs and is selected from 1, 2, 3, 4 or 5;

[0252] X1-X4 are each independently selected from C or N;

[0253] K1-K4 are each independently selected from a single bond, O or S;

[0254] R n Each occurrence of the same or different means mono-, poly- or no-substitution;

[0255] R q , R nEach occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0256] Adjacent substituent R q , R n The substituents can be optionally linked to form a ring.

[0257] In this embodiment, "the adjacent substituent R q , R n "can optionally be linked to form a ring" is intended to mean that adjacent substituent groups, for example, two substituents R q Between the two substituents R n Between, and the substituent R q and R n In between, any one or more of these adjacent substituent groups can be connected to form a ring. Obviously, these adjacent substituent groups can also not be connected to form a ring.

[0258] According to one embodiment of the present invention, the phosphorescence sensitizer has a structure represented by Formula 21-1:

[0259]

[0260] In formula 21-1,

[0261] Ring F, Ring G, and Ring H are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof; Ring I is selected from an unsaturated heterocyclic ring having 1 to 30 carbon atoms;

[0262] A1, A2 are each independently selected from a single bond, O, S, Se, (SiR q R q ) y , PR q ,NR q , (CR q R q ) y , a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof; y is the same or different when each occurs and is selected from 1, 2, 3, 4 or 5;

[0263] K1-K4 are each independently selected from a single bond, O or S;

[0264] X1-X3 are each independently selected from C or N;

[0265] R n Each occurrence represents identically or differently monosubstituted, polysubstituted or unsubstituted;

[0266] R, R q , R n Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0267] Adjacent substituents R, R q , R n Can optionally be linked to form a ring.

[0268] In this embodiment, "adjacent substituents R, R q , R n"can optionally be linked to form a ring" is intended to mean that adjacent substituent groups, for example, two substituents R q Between the two substituents R n Between, the substituent R q and R n between, and between substituents R and R n In between, any one or more of these adjacent substituent groups can be connected to form a ring. Obviously, these adjacent substituent groups can also not be connected to form a ring.

[0269] According to one embodiment of the present invention, in Formula 21 or Formula 21-1, Ring F, Ring G, and Ring H are each independently selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6-30 carbon atoms, or a heteroaromatic ring having 3-30 carbon atoms; Ring I is the same or different each time it appears and is selected from an unsaturated heterocyclic ring having 3-30 carbon atoms.

[0270] According to one embodiment of the present invention, in Formula 21 or Formula 21-1, Ring F, Ring G, and Ring H are each independently selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6-18 carbon atoms, or a heteroaromatic ring having 3-18 carbon atoms; Ring I is the same or different each time it appears and is selected from an unsaturated heterocyclic ring having 3-18 carbon atoms.

[0271] According to one embodiment of the present invention, in Formula 21 or Formula 21-1, wherein the ring F, ring G, and ring H are each independently selected from a benzene ring, a pyridine ring, an indene ring, a fluorene ring, an indole ring, a carbazole ring, a benzofuran ring, a dibenzofuran ring, a benzosilole ring, a dibenzosilole ring, a benzothiophene ring, a dibenzothiophene ring, a dibenzoselenophene ring, a cyclopentadiene ring, a furan ring, a thiophene ring, or a silole ring; the ring I is selected from an imidazole carbene ring or a benzimidazole carbene ring the same or differently each time it appears.

[0272] According to one embodiment of the present invention, wherein said K1-K4 is selected from single bonds.

[0273] According to one embodiment of the present invention, the phosphorescence sensitizer has a structure represented by one of Formula 3-1 to Formula 3-24:

[0274]

[0275]

[0276]

[0277]

[0278] in,

[0279] A2 is selected, at each occurrence, identically or differently, from a single bond, O, S, Se, (SiR q R q ) y , PR q ,NR q , a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof; y is the same or different when each occurs and is selected from 1, 2 or 3;

[0280] U1-U 20 Each occurrence is the same or different selection from CR n or N;

[0281] Ring F3 is identically or differently selected at each occurrence from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof;

[0282] Q is selected, identically or differently, from O, S or Se at each occurrence;

[0283] m is selected from 0, 1, 2 or 3, the same or different at each occurrence;

[0284] R u Each occurrence represents identically or differently monosubstituted, polysubstituted or unsubstituted;

[0285] R, R N , R q , R u , R n , R f3 , R a , R b and R cEach occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0286] Adjacent substituents R, R N , R q , R u , R n and R f3 Can optionally be linked to form a ring.

[0287] In this embodiment, "adjacent substituents R, R N , R q , R u , R n and R f3 "can optionally be linked to form a ring" is intended to mean that adjacent substituent groups, for example, two substituents R q Between the two substituents R u Between the two substituents R n Between the two substituents R f3 Between the substituents R and R u Between the substituents R and R n Between, the substituent R N and R n Between, the substituent R f3 and R n Between, and the substituent R q and R n In between, any one or more of these adjacent substituent groups can be connected to form a ring. Obviously, these adjacent substituent groups can also not be connected to form a ring.

[0288] According to one embodiment of the present invention, the phosphorescence sensitizer has a structure represented by Formula 3-1 or Formula 3-2.

[0289] According to one embodiment of the present invention, wherein said A2 is selected from a single bond, O or S.

[0290] According to one embodiment of the present invention, wherein said A2 is selected from O.

[0291] According to one embodiment of the present invention, the U1-U 20 Each occurrence is the same or different selection from CR n ; and said R n Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, and combinations thereof.

[0292] According to one embodiment of the present invention, wherein the R n Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, fluorine, methyl, deuterated methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, tert-butyl, cyclopentyl, cyclohexyl, phenyl, trimethylsilyl, carbazolyl, indolyl, benzofuranyl, dibenzofuranyl, benzothioyl, dibenzothioyl, benzothiophenyl, dibenzothiophenyl, dibenzoselenophene, and combinations thereof.

[0293] According to one embodiment of the present invention, the substituent R has a structure represented by Formula 4:

[0294]

[0295] In formula 4,

[0296] Ring M and Ring W are identically or differently selected at each occurrence from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof;

[0297] X5-X8 are each identically or differently selected from C or N;

[0298] “*” indicates the connection position of the formula 4;

[0299] R m Each occurrence represents identically or differently monosubstituted, polysubstituted or unsubstituted;

[0300] Rw Each occurrence is identical or different, indicating mono- or polysubstitution;

[0301] R m and R w Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0302] Adjacent substituent R m , R w Can optionally be linked to form a ring.

[0303] In this context, “the adjacent substituent R m , R w "can optionally be linked to form a ring" is intended to mean that adjacent substituent groups, for example, two substituents R m Between the two substituents R w Between, and the substituent R m and R w In between, any one or more of these adjacent substituent groups can be connected to form a ring. Obviously, these adjacent substituent groups can also not be connected to form a ring.

[0304] According to one embodiment of the present invention, the substituent R has a structure represented by Formula 4-1:

[0305]

[0306] In formula 4-1,

[0307] M1 to M 10 Each independently selected from CRm or N;

[0308] W1 to W3 are each independently selected from CR w or N;

[0309] “**” indicates the connection position of the formula 4-1;

[0310] R m and R w Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0311] Adjacent substituent R m , R w Can optionally be linked to form a ring.

[0312] According to one embodiment of the present invention, there is at least one R in Formula 4 or Formula 4-1. wselected from the group consisting of deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 2 to 20 carbon atoms, atom, an alkynyl group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof.

[0313] According to one embodiment of the present invention, wherein the M1 to M 10 Each independently selected from CR m .

[0314] According to one embodiment of the present invention, W1 to W3 are each independently selected from CR w .

[0315] According to one embodiment of the present invention, wherein the R m and R w Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, cyano, hydroxyl, mercapto, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, and combinations thereof.

[0316] According to one embodiment of the present invention, wherein the M1 to M 10 Selected from CH or CD.

[0317] According to one embodiment of the present invention, wherein said W2 is selected from CR w , the R wSelected from the group consisting of deuterium, halogen, cyano, hydroxyl, mercapto, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted aryl having 6-30 carbon atoms, substituted or unsubstituted heteroaryl having 3-30 carbon atoms, substituted or unsubstituted alkylsilyl having 3-20 carbon atoms, substituted or unsubstituted arylsilyl having 6-20 carbon atoms, and combinations thereof.

[0318] According to one embodiment of the present invention, the phosphorescence sensitizer has Pt(L a )(L b ) structure represented by the general formula, wherein L a and L b are the first ligand and the second ligand coordinated with the metal Pt, respectively. For example, the L a It has a structure represented by formula A: The “#” in formula A indicates that b The location of the connection; the L b Having a structure represented by formula B: Wherein Indicates that L a The location of the connection.

[0319] According to one embodiment of the present invention, the phosphorescence sensitizer has Ir(L a ) m (L b ) 3-m The general structure of the present invention is represented by the formula Ma:

[0320]

[0321] in,

[0322] m is selected from 1, 2 or 3; when m is selected from 1, two L b Same or different; when m is selected from 2 or 3, multiple L a Same or different;

[0323] Ring F is selected from heteroaromatic rings having 5 to 30 ring atoms;

[0324] Ring G is selected from an aromatic ring having 6 to 30 ring atoms, a heteroaromatic ring having 5 to 30 ring atoms, or a combination thereof;

[0325] U1 to U8 are selected from CR in the same or different ways each time they appear. n or N;

[0326] R f and R gEach occurrence of the same or different means mono-, poly- or no-substitution;

[0327] R f , R g and R n Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0328] Adjacent substituent R f , R g and R n Can optionally be linked to form a ring.

[0329] According to one embodiment of the present invention, the ring F is selected from any one of the following structures:

[0330]

[0331] The ring G is selected from any one of the following structures:

[0332]

[0333]

[0334] in,

[0335] Q' is selected from O, S, Se, NR Q , CR Q R Q , SiR Q R Q and GeR Q R Q When there are multiple RQ When multiple R Q Same or different;

[0336] R f , R g Each occurrence is the same or different and represents mono-, poly-, or unsubstituted; when multiple R f or R g When the R f or R g Same or different;

[0337] R f , R g , R Q Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0338] Adjacent substituent R f , R g , R Q can optionally be linked to form a ring;

[0339] Among them, “#” indicates the position connected to the metal Ir, Indicates the position where it is connected to ring G.

[0340] According to one embodiment of the present invention, the ring F is selected from The ring G is selected from

[0341] According to one embodiment of the present invention, the phosphorescence sensitizer has Ir(L a )m (L b ) 3-m The general structure of the formula and the structure represented by the formula Ma-0:

[0342]

[0343] in,

[0344] m is selected from 1, 2 or 3; when m is selected from 1, two L b are the same or different; when m is selected from 2 or 3, 2 or 3 L a are the same or different;

[0345] Q' is selected from O, S, Se, NR Q , CR Q R Q , SiR Q R Q and GeR Q R Q When there are multiple R Q When multiple R Q Same or different;

[0346] U 15 to U 20 Each occurrence is the same or different selection from CR n1 or N;

[0347] U9 to U 12 Each occurrence is the same or different selection from CR n2 or N;

[0348] R n Each occurrence is identical or different and represents mono-, poly-, or unsubstituted;

[0349] R n1 , R n2 , R Q , R nEach occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0350] Adjacent substituent R n1 , R n2 , R Q , R n Can optionally be linked to form a ring.

[0351] According to one embodiment of the present invention, Q' is selected from O, S, Se, NR Q or CR Q R Q .

[0352] According to one embodiment of the present invention, the Q' is selected from O or S.

[0353] According to one embodiment of the present invention, U9 to U 12 Each occurrence is the same or different selection from CR n2 , U 15 to U 19 Each occurrence is the same or different selection from CR n1 , U 20 Selected from CR n1 or N; said R n1 , R n2Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, cyano, hydroxyl, mercapto, and combinations thereof.

[0354] According to one embodiment of the present invention, U 15 to U 20 At least two of them are selected from CR n1 , and one of the R n1 is cyano or fluoro; the other R n1 selected from the group consisting of deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 2 to 20 carbon atoms, atom, an alkynyl group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof.

[0355] According to one embodiment of the present invention, U 15 to U 20 At least two of them are selected from CR n1 , and one of the R n1 is cyano or fluoro; the other R n1 Selected from the group consisting of deuterium, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted aryl having 6-30 carbon atoms, substituted or unsubstituted heteroaryl having 3-30 carbon atoms, and combinations thereof.

[0356] According to one embodiment of the present invention, U 19 Selected from CR n1 , and the R n1 is cyano or fluorine, U 20 Selected from CR n1 , and the R n1 is selected from deuterium, a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 18 carbon atoms, or a combination thereof.

[0357] According to one embodiment of the present invention, R n Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, cyano, and combinations thereof.

[0358] According to one embodiment of the present invention, R n Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, fluorine, substituted or unsubstituted alkyl having 1 to 6 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted aryl having 6 to 12 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 12 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 12 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 12 carbon atoms, and combinations thereof.

[0359] According to one embodiment of the present invention, the phosphorescent sensitizer is selected from the group consisting of BD1 to BD18, RD1 to RD209 and GD1 to GD177. For the specific structure of the group consisting of BD1 to BD18, RD1 to RD209 and GD1 to GD177, please refer to claim 17.

[0360] According to one embodiment of the present invention, the phosphorescence sensitizer has Pt(L a )(L b ) represents a structure where L a and L b are the first ligand and the second ligand coordinated with the metal Pt, respectively. a Choose from L a 1-1 to L a 1-25 and L a 2-1 to L a 2-10 groups, the L bChoose from L b 1-1 to L b 1-8 and L b 2-1 to L b 2-24 groups, the L a 1-1 to L a 1-25, L a 2-1 to L a 2-10, L b 1-1 to L b 1-8 and L b 2-1 to L b The specific structure of 2-24 is shown in claim 17.

[0361] According to one embodiment of the present invention, the phosphorescent sensitizer is selected from the group consisting of Pt1 to Pt96, wherein the Pt1 to Pt96 have Pt(L a )(L b ) represents the structure, and the specific structure of Pt1 to Pt96 can be found in claim 17.

[0362] According to one embodiment of the present invention, the first host compound has a structure represented by one of Formula 5 to Formula 7:

[0363]

[0364] In Formula 5, Z1 to Z3 are selected from CR4 or N at each occurrence, the same or different, and at least one of Z1 to Z3 is N;

[0365] L is identically or differently selected at each occurrence from the group consisting of a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, and combinations thereof;

[0366] In Formula 6 and Formula 7, Z4 is selected from CR4 or N at each occurrence, the same or different, and at least one Z4 is N;

[0367] Z is selected from O or S in the same or different manner at each occurrence;

[0368] R1-R4 are each identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted substituted or unsubstituted alkynyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amino groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

[0369] Adjacent substituents R4 can optionally be linked to form a ring.

[0370] Herein, "adjacent substituents R4 can be optionally connected to form a ring" is intended to mean that two adjacent substituents R4 can be connected to form a ring. Obviously, two adjacent substituents R4 may not be connected to form a ring.

[0371] According to one embodiment of the present invention, the first host compound has a structure represented by Formula 5-1 or Formula 6-1:

[0372]

[0373] In formula 5-1,

[0374] R1 and R2 are each independently selected from a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms;

[0375] L is selected from a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof;

[0376] In formula 6-1,

[0377] Z is selected from O or S;

[0378] Z 41 -Z 48Each occurrence is identically or differently selected from CR4, CR4' or N, and Z 41 -Z 48 At least one of them is selected from N, and at least one of them is selected from CR4';

[0379] R4' is the same or different at each occurrence and is selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, or a combination thereof;

[0380] R L , R4 is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0381] Adjacent substituents R4 can optionally be linked to form a ring.

[0382] According to one embodiment of the present invention, each occurrence of L is identically or differently selected from the group consisting of: a single bond, a substituted or unsubstituted arylene group having 6 to 18 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 18 carbon atoms, and combinations thereof.

[0383] According to one embodiment of the present invention, each occurrence of L is identically or differently selected from the group consisting of: a single bond, a phenylene group, a biphenylene group, a fluorenyl group, a triphenylene group, a furanyl group, a thienyl group, a dibenzofuranyl group, a dibenzothienyl group, and combinations thereof.

[0384] According to one embodiment of the present invention, wherein the R LEach occurrence is identically or differently selected from the group consisting of substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, and combinations thereof.

[0385] According to one embodiment of the present invention, wherein the R L and are selected, identically or differently on each occurrence, from substituted or unsubstituted aryl radicals having 6 to 30 carbon atoms.

[0386] According to one embodiment of the present invention, wherein the R L Each occurrence is identically or differently selected from the group consisting of phenyl, biphenyl, triphenylene, indenyl, fluorenyl, indolyl, carbazolyl, benzofuranyl, dibenzofuranyl, benzothiazolyl, dibenzothiazolyl, benzothiophene, dibenzothiophene, dibenzoselenophene, and combinations thereof.

[0387] According to one embodiment of the present invention, each occurrence of R1 to R4 is the same or different and is selected from the group consisting of: hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted aryl having 6-30 carbon atoms, substituted or unsubstituted heteroaryl having 3-30 carbon atoms, and combinations thereof.

[0388] According to one embodiment of the present invention, each occurrence of R1 to R4 is the same or different and is selected from the group consisting of: hydrogen, deuterium, halogen, cyano, substituted or unsubstituted aryl having 6-18 carbon atoms, substituted or unsubstituted heteroaryl having 3-18 carbon atoms, and combinations thereof.

[0389] According to one embodiment of the present invention, each occurrence of R1 to R4 is the same or different and is selected from the group consisting of: hydrogen, deuterium, fluorine, cyano, phenyl, biphenyl, triphenylene, indenyl, fluorenyl, indolyl, carbazolyl, benzofuranyl, dibenzofuranyl, benzothiole, dibenzothiole, benzothiophene, dibenzothiophene, dibenzoselenophene, triazine, and combinations thereof.

[0390] According to one embodiment of the present invention, in Formula 6-1, the Z 41 -Z 48 At least one of them is selected from N, and at least two of them are selected from CR4'.

[0391] According to one embodiment of the present invention, in Formula 6-1, the Z 41 -Z 48Only one of them is selected from N, and only two of them are selected from CR4'.

[0392] According to one embodiment of the present invention, in Formula 6-1, the Z 42 Selected from N, Z 41 and Z 46 Selected from CR4'.

[0393] According to one embodiment of the present invention, the first host compound has a structure represented by Formula 5-2 or Formula 5-3:

[0394]

[0395] in,

[0396] Z is selected from the group consisting of O, S and Se at each occurrence, the same or different;

[0397] In formula 5-2, Z 51 -Z 58 Each occurrence is identically or differently selected from C, CR5 or N, one of which is C, and is linked to L;

[0398] In formula 5-3, Z 51 -Z 58 Each occurrence is identically or differently selected from CR5 or N;

[0399] W 51 -W 55 Each occurrence is the same or different from C, CR w1 or N, and one of them is C, and with the structure connected;

[0400] R1 and R2 are the same or different at each occurrence and are selected from substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, or a combination thereof;

[0401] R5 and R w1Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;

[0402] Adjacent substituent R w1 can optionally be linked to form a ring;

[0403] Adjacent substituents R5 can optionally be linked to form a ring.

[0404] According to one embodiment of the present invention, the first main compound is selected from the group consisting of compound N-1-1 to compound N-1-60, compound N-2-1 to compound N-2-35, compound N-3-1 to compound N-3-9 and compound N-4-1 to compound N-4-34, and the specific structures of compound N-1-1 to compound N-1-60, compound N-2-1 to compound N-2-35, compound N-3-1 to compound N-3-9 and compound N-4-1 to compound N-4-34, and compound NH-1 to compound NH-224 are shown in claim 18.

[0405] According to one embodiment of the present invention, the hydrogen in the structures of compounds N-1-1 to N-1-53, compound N-1-58, compound N-2-1 to N-2-32, compound N-3-1 to N-3-7 and compound N-4-1 to N-4-34, and compound NH-1 to NH-224 can be partially or completely replaced by deuterium.

[0406] According to one embodiment of the present invention, the second host compound has a structure represented by Formula 8, Formula 9 or Formula 10:

[0407]

[0408] L 11 is selected from a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof;

[0409] Ar 11 is selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted amino group having 0 to 30 carbon atoms, or a combination thereof;

[0410] G' is selected from C(R g ')2、NR g ', O or S;

[0411] V is selected, identically or differently, at each occurrence from C, CR6 or N;

[0412] Each occurrence of R6 is the same or different and represents mono-, poly- or non-substituted;

[0413] R6, R g 'Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkyl having 2 to 20 carbon atoms alkenyl, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphino, and combinations thereof;

[0414] Adjacent substituents R6 can optionally be linked to form a ring.

[0415] Herein, "adjacent substituents R6 can be optionally connected to form a ring" is intended to mean that two adjacent substituents R6 can be connected to form a ring. Obviously, two adjacent substituents R6 may not be connected to form a ring.

[0416] According to one embodiment of the present invention, the second host compound has a structure represented by Formula 8-1 or Formula 8-2:

[0417]

[0418] L 11 , L 12 is selected from a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof;

[0419] Ar 11 is selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted amino group having 0 to 30 carbon atoms, or a combination thereof;

[0420] Each occurrence of R6 is the same or different and represents mono-, poly- or non-substituted;

[0421] R6 is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkyl having 2 to 20 carbon atoms, alkenyl, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphino, and combinations thereof;

[0422] Adjacent substituents R6 can optionally be linked to form a ring.

[0423] According to one embodiment of the present invention, the second host compound has a structure represented by Formula 8-3 or Formula 8-4:

[0424]

[0425] Ar 11 is selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted amino group having 0 to 30 carbon atoms, or a combination thereof;

[0426] L 11 is selected from a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof;

[0427] Each occurrence of R6 is the same or different and represents mono-, poly- or non-substituted;

[0428] R6 is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkyl having 2 to 20 carbon atoms, alkenyl, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphino, and combinations thereof;

[0429] Adjacent substituents R6 can optionally be linked to form a ring.

[0430] According to one embodiment of the present invention, R6 is selected from the group consisting of hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 ring carbon atoms, substituted or unsubstituted aryl having 6-30 carbon atoms, substituted or unsubstituted heteroaryl having 3-30 carbon atoms, substituted or unsubstituted alkylsilyl having 3-20 carbon atoms, substituted or unsubstituted arylsilyl having 6-20 carbon atoms, and combinations thereof.

[0431] According to one embodiment of the present invention, each occurrence of R6 is identically or differently selected from the group consisting of: hydrogen, deuterium, halogen, cyano, substituted or unsubstituted aryl having 6-18 carbon atoms, substituted or unsubstituted heteroaryl having 3-18 carbon atoms, and combinations thereof.

[0432] According to one embodiment of the present invention, each occurrence of R6 is the same or different and is selected from the group consisting of: hydrogen, deuterium, fluorine, cyano, phenyl, biphenyl, triphenylene, indenyl, fluorenyl, indolyl, carbazolyl, benzofuranyl, dibenzofuranyl, benzothiole, dibenzothiole, benzothiophene, dibenzothiophene, dibenzoselenophene, and combinations thereof.

[0433] According to one embodiment of the present invention, the second host compound is selected from the group consisting of compound P-1 to compound P-66, and the specific structures of compound P-1 to compound P-66 and compound PH-1 to compound PH-223 are shown in claim 19.

[0434] According to one embodiment of the present invention, hydrogen in the structures of Compounds P-1 to P-23, Compounds P-27 to P-38, and Compounds PH-1 to PH-223 can be partially or completely replaced by deuterium.

[0435] According to one embodiment of the present invention, the LUMO energy level of the first host compound is less than or equal to -2.30 eV.

[0436] According to one embodiment of the present invention, the LUMO energy level of the first host compound is less than or equal to -2.50 eV.

[0437] According to one embodiment of the present invention, the LUMO energy level of the first host compound is less than or equal to -2.65 eV.

[0438] According to one embodiment of the present invention, the LUMO energy level of the first host compound is less than or equal to -2.80 eV.

[0439] According to one embodiment of the present invention, the HOMO energy level of the second host compound is greater than or equal to -5.70 eV.

[0440] According to one embodiment of the present invention, the HOMO energy level of the second host compound is greater than or equal to -5.60 eV.

[0441] According to one embodiment of the present invention, the HOMO energy level of the second host compound is greater than or equal to -5.56 eV.

[0442] According to one embodiment of the present invention, the first host compound and the second host compound may be the same or different.

[0443] According to one embodiment of the present invention, the first host compound and the second host compound are different.

[0444] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 65%-98.9% of the total weight of the composition, the weight of the phosphorescent sensitizer accounts for 1%-30% of the total weight of the composition, and the weight of the fluorescent compound accounts for 0.1%-5% of the total weight of the composition.

[0445] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 82%-94.5% of the total weight of the composition, the weight of the phosphorescent sensitizer accounts for 5%-15% of the total weight of the composition, and the weight of the fluorescent compound accounts for 0.5%-3% of the total weight of the composition.

[0446] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 86.5%-91.5% of the total weight of the composition, the weight of the phosphorescent sensitizer accounts for 8%-12% of the total weight of the composition, and the weight of the fluorescent compound accounts for 0.5%-1.5% of the total weight of the composition.

[0447] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 85%-98% of the total weight of the composition, the weight of the phosphorescent sensitizer accounts for 1.5%-12% of the total weight of the composition, and the weight of the fluorescent compound accounts for 0.5%-3% of the total weight of the composition.

[0448] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 87.5%-97.5% of the total weight of the composition, the weight of the phosphorescent sensitizer accounts for 2%-10% of the total weight of the composition, and the weight of the fluorescent compound accounts for 0.5%-2.5% of the total weight of the composition.

[0449] According to one embodiment of the present invention, application of the composition in an organic electroluminescent device is disclosed.

[0450] According to one embodiment of the present invention, disclosed is the use of the composition in a light-emitting layer of an organic electroluminescent device.

[0451] According to one embodiment of the present invention, the composition is applied to an organic electroluminescent device.

[0452] According to one embodiment of the present invention, the composition is applied to a light-emitting layer in an organic electroluminescent device.

[0453] According to one embodiment of the present invention, the composition is applied to a light-emitting layer in an organic electroluminescent device, the first host compound and the second host compound are host materials, and the fluorescent compound is a light-emitting material.

[0454] According to one embodiment of the present invention, the composition is applied to a light-emitting layer in an organic electroluminescent device, the first host compound and the second host compound are host materials, the fluorescent compound is an E-type delayed fluorescence compound, and the E-type delayed fluorescence compound is a light-emitting material.

[0455] According to one embodiment of the present invention, an electroluminescent device is disclosed, comprising:

[0456] anode,

[0457] cathode,

[0458] and an organic layer disposed between the anode and cathode, the organic layer comprising the composition as described in any one of the above embodiments;

[0459] The composition comprises a premix and a phosphorescent sensitizer, wherein the premix comprises a first host compound, a second host compound and a fluorescent compound;

[0460] wherein the triplet energy levels of the first host compound, the second host compound, and the phosphorescence sensitizer are all higher than the triplet energy level of the fluorescent compound;

[0461] wherein the first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.;

[0462] wherein the second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.;

[0463] The absolute value of the difference between T1 and T2 is less than or equal to 20°C.

[0464] In this embodiment, the premixture is obtained by premixing the first host compound, the second host compound and the fluorescent compound before the device is prepared. During the device preparation, the premixture is placed in a single evaporation source in a high vacuum deposition tool.

[0465] According to one embodiment of the present invention, the organic layer is a light-emitting layer, the first host compound and the second host compound are host materials, and the fluorescent compound is a light-emitting material.

[0466] According to an embodiment of the present invention, the (main) source of light emitted by the device is light emitted by a fluorescent compound.

[0467] According to an embodiment of the present invention, the device emits blue light.

[0468] According to one embodiment of the present invention, the device emits deep blue light.

[0469] According to an embodiment of the present invention, the device emits green light.

[0470] According to an embodiment of the present invention, the device emits red light.

[0471] According to an embodiment of the present invention, the device emits white light.

[0472] According to one embodiment of the present invention, the maximum emission wavelength of the device is 460nm-470nm.

[0473] According to one embodiment of the present invention, the maximum emission wavelength of the device is 525nm-550nm.

[0474] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 65%-98.9% of the total weight of the light-emitting layer material, the weight of the phosphorescent sensitizer accounts for 1%-30% of the total weight of the light-emitting layer material, and the weight of the fluorescent compound accounts for 0.1%-5% of the total weight of the light-emitting layer material.

[0475] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 82%-94.5% of the total weight of the light-emitting layer material, the weight of the phosphorescent sensitizer accounts for 5%-15% of the total weight of the light-emitting layer material, and the weight of the fluorescent compound accounts for 0.5%-3% of the total weight of the light-emitting layer material.

[0476] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 86.5%-91.5% of the total weight of the light-emitting layer material, the weight of the phosphorescent sensitizer accounts for 8%-12% of the total weight of the light-emitting layer material, and the weight of the fluorescent compound accounts for 0.5%-1.5% of the total weight of the light-emitting layer material.

[0477] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 85%-98% of the total weight of the light-emitting layer material, the weight of the phosphorescent sensitizer accounts for 1.5%-12% of the total weight of the light-emitting layer material, and the weight of the fluorescent compound accounts for 0.5%-3% of the total weight of the light-emitting layer material.

[0478] According to one embodiment of the present invention, the weight of the first host compound and the second host compound accounts for 87.5%-97.5% of the total weight of the light-emitting layer material, the weight of the phosphorescent sensitizer accounts for 2%-10% of the total weight of the light-emitting layer material, and the weight of the fluorescent compound accounts for 0.5%-2.5% of the total weight of the light-emitting layer material.

[0479] According to one embodiment of the present invention, the ratio of the first host compound to the second host compound can be 99:1 to 1:99; or the ratio can be 80:20 to 20:80; or the ratio can be 70:30 to 30:70; or the ratio can be 60:40 to 40:60; or the ratio can be 50:50.

[0480] According to one embodiment of the present invention, a method for preparing an organic electroluminescent device is disclosed, wherein the organic electroluminescent device includes an anode, a cathode, and an organic layer disposed between the anode and the cathode, and the organic layer includes the composition described in any of the above embodiments. The preparation method includes:

[0481] Step 1: providing a substrate and arranging the anode thereon;

[0482] Step 2: Pre-mixing a first host compound, a second host compound, and a fluorescent compound to form a pre-mixture, and placing the pre-mixture in an evaporation source 1 in a high vacuum deposition tool; placing a phosphorescent sensitizer in an evaporation source 2 in the high vacuum deposition tool; then co-evaporating the pre-mixture in the evaporation source 1 and the phosphorescent sensitizer in the evaporation source 2, and co-evaporating the pre-mixture in the evaporation source 1 and the phosphorescent sensitizer in the evaporation source 2 on a surface positioned at a certain distance from the deposited pre-mixture and phosphorescent sensitizer to form the organic layer;

[0483] wherein the triplet energy levels of the first host compound, the second host compound, and the phosphorescence sensitizer are all higher than the triplet energy level of the fluorescent compound;

[0484] wherein the first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.;

[0485] wherein the second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.;

[0486] The absolute value of the difference between T1 and T2 is less than or equal to 20°C;

[0487] Step 3: Depositing the cathode on the organic layer.

[0488] In this embodiment, the premixture in the evaporation source 1 and the phosphorescent sensitizer in the evaporation source 2 in the high vacuum deposition tool are co-evaporated. Those skilled in the art can select appropriate vacuum degree and evaporation rate according to actual needs to achieve the purpose of evaporation. For example, and not limitation, the vacuum degree can be 10 -6 Torr or lower, for example, the vacuum degree can be 10 -7 Torr or 10 -8 Torr, the evaporation rate can be 0.2-2 angstroms / second.

[0489] In this embodiment, the "certain distance" described during the process of vapor-depositing the premixture and the phosphorescent sensitizer to form the organic layer can be adaptively adjusted by those skilled in the art according to actual needs to achieve the vapor deposition purpose. By way of example and not limitation, the certain distance can be 10-100 cm, or 30-80 cm, or 35-60 cm.

[0490] The device prepared using the preparation method herein may further comprise other organic layers, which may be disposed between the organic layer formed in step 2 and the anode or cathode, and may be prepared by providing other steps between steps 1 and 2 or between steps 2 and 3. The organic layer formed in step 2 is preferably a light-emitting layer.

[0491] According to one embodiment of the present invention, the evaporation rate of the first host compound at the evaporation temperature T1 and a specific vacuum degree can be 0.01-10 angstroms / second, or 0.1-10 angstroms / second, or 0.1-5 angstroms / second, or 0.1-2 angstroms / second; the evaporation rate of the second host compound at the evaporation temperature T2 and a specific vacuum degree can be 0.01-10 angstroms / second, or 0.1-10 angstroms / second, or 0.1-5 angstroms / second, or 0.1-2 angstroms / second; the evaporation rate of the fluorescent compound at the evaporation temperature T3 and a specific vacuum degree can be 0.01-2 angstroms / second, or 0.01-1 angstroms / second, or 0.01-0.5 angstroms / second, or 0.01-0.2 angstroms / second.

[0492] According to one embodiment of the present invention, the premixture consists of the first host compound, the second host compound and a fluorescent compound.

[0493] According to one embodiment of the present invention, the premixture is formed by physically mixing the first host compound, the second host compound and the fluorescent compound.

[0494] According to one embodiment of the present invention, the specific definitions of the first host compound, the second host compound and the fluorescent compound in the premixture are as described in any of the aforementioned embodiments.

[0495] According to one embodiment of the present invention, the premixture is a solid mixture.

[0496] According to one embodiment of the present invention, a use of a premixture in a sensitizer device is disclosed. The premixture is as described in the above embodiment, and the premixture is co-evaporated with a phosphorescent sensitizer to prepare the sensitizer device.

[0497] Combination with other materials

[0498] The materials described herein for use in specific layers of organic light-emitting devices can be used in combination with various other materials present in the device. Combinations of these materials are described in detail in U.S. Patent Application No. US2016 / 0359122A1, paragraphs 0132-0161, the entire contents of which are incorporated herein by reference. The materials described or mentioned therein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can readily consult the literature to identify other materials that can be used in combination.

[0499] The materials described herein as being useful in specific layers of an organic light-emitting device can be used in combination with a variety of other materials present in the device. For example, the compounds disclosed herein can be used in combination with a variety of hosts, transport layers, barrier layers, injection layers, electrodes, and other layers that may be present. The combination of these materials is described in detail in paragraphs 0080-0101 of U.S. patent application US2015 / 0349273A1, the entire contents of which are incorporated herein by reference. The materials described or mentioned therein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily consult the literature to identify other materials that can be used in combination.

[0500] The first host compound, the second host compound, the phosphorescence sensitizer and the thermally activated delayed fluorescence compound used in the present invention can be easily obtained by referring to the preparation methods in the prior art, and their preparation methods will not be described in detail here.

[0501] The preparation method of the organic electroluminescent device is not limited. The preparation method of the following embodiment is only an example and should not be construed as limiting. Those skilled in the art can reasonably improve the preparation method of the following embodiment based on existing technology. For example, the ratio of the various materials in the light-emitting layer is not particularly limited. Those skilled in the art can reasonably select within a certain range based on existing technology. For example, based on the total weight of the light-emitting layer materials, the two host compounds can account for 65%-98.9%, the phosphorescence sensitizer can account for 1%-30%, and the thermally activated delayed fluorescence compound can account for 0.1%-5%; or the two host compounds can account for 82%-94.5%, the phosphorescence sensitizer can account for 5%-15%, and the thermally activated delayed fluorescence compound can account for 0.5%-3%; or the two host compounds can account for 86.5%-91.5%, the phosphorescence sensitizer can account for 8%-12%, and the thermally activated delayed fluorescence compound can account for 0.5%-1.5%. In addition, the ratio of the two host compounds can be 99:1 to 1:99; or the ratio can be 80:20 to 20:80; or the ratio can be 70:30 to 30:70. In the device embodiments, the device characteristics are also tested using conventional equipment in the field (including but not limited to evaporation machines produced by Angstrom Engineering, optical testing systems and life testing systems produced by Suzhou Fushida, and ellipsometers produced by Beijing Liangtuo, etc.) using methods well known to those skilled in the art.

[0502] In the present invention, the evaporation temperature is set at a vacuum degree of about 10 -8 The temperature when evaporating at a rate of 0.2-2 angstroms / second in the case of 1000 torr.

[0503] The evaporation temperatures of the following first host compound, second host compound, and thermally activated delayed fluorescent compound are shown in Table 2:

[0504] Table 2 Evaporation temperature data

[0505]

[0506]

[0507] In the present invention, the preparation method of the premixture is not limited. For example, the solid powders of the first host compound, the second host compound and the thermally activated delayed fluorescence compound can be mixed in a certain weight ratio, and the mixture is heated and melted twice under a certain vacuum degree. The solid obtained by cooling is then ground into powder to obtain the premixture.

[0508] The preparation method of the premix PM1-PM6 is as follows:

[0509] Preparation of premix PM1:

[0510] The first main compound N-1-15, the second main compound P-22 and the thermally activated delayed fluorescence compound BN-BD-2 were physically mixed in a weight ratio of 49:49:2, and rolled into a sample bottle and placed in a vacuum chamber. -3 Pa, heat to 290 ° C, maintain the temperature for 0.5 hours, cool to room temperature, and then put the sample bottle into the container again while maintaining the vacuum degree greater than 10 -3 Pa, heated to 290 ° C, maintained at this temperature for 0.5 hours, and then cooled to room temperature. The molten solid was ground into powder to obtain the premix PM1.

[0511] Preparation of premix PM2:

[0512] The preparation method of premix PM2 is the same as that of premix PM1, except that compound BN-BD-20 replaces BN-BD-2, and the molten solid is ground into powder to obtain premix PM2.

[0513] Preparation of premix PM3:

[0514] The preparation method of premix PM3 is the same as that of premix PM1, except that compound BN-BD-34 replaces BN-BD-2, and the molten solid is ground into powder to obtain premix PM3.

[0515] Preparation of premix PM4:

[0516] The preparation method of premix PM4 is the same as that of premix PM1, except that compound BN-BD-1 replaces BN-BD-2, and the molten solid is ground into powder to obtain premix PM4.

[0517] Preparation of premix PM5:

[0518] The preparation method of premix PM5 is the same as that of premix PM1, except that the weight ratio of the second host compound P-22, the first host compound N-1-15, and the thermally activated delayed fluorescence compound BN-BD-2 is 59:39:2. The melted solid is ground into a powder to obtain premix PM5.

[0519] Preparation of premix PM6:

[0520] The preparation method of premix PM6 is the same as that of premix PM1, except that the weight ratio of the second host compound P-22, the first host compound N-1-15, and the thermally activated delayed fluorescence compound BN-BD-2 is 39:59:2. The melted solid is ground into a powder to obtain premix PM6.

[0521] The specific structures of the compounds used in the above-mentioned premixes PM1 to PM6 are as follows:

[0522]

[0523] The preparation methods of premix PM7-PM10 and comparison premix C-PM1 are as follows:

[0524] Preparation of premix PM7:

[0525] The first main compound PH-24, the second main compound NH-144 and the thermally activated delayed fluorescence compound BN-GD-12 were physically mixed in a weight ratio of 73.5:24.5:2, and rolled into a sample bottle and placed in a vacuum chamber. -3 Pa, heat to 290 ° C, maintain the temperature for 0.5 hours, cool to room temperature, and then put the sample bottle into the container again while maintaining the vacuum degree greater than 10 -3 Pa, heated to 290 ° C, maintained at this temperature for 0.5 hours, and then cooled to room temperature. The molten solid was ground into powder to obtain the premix PM7.

[0526] Preparation of premix PM8:

[0527] Premix PM8 was prepared in the same manner as premix PM7, except that the ratio of the first host compound PH-24, the second host compound NH-144, and the thermally activated delayed fluorescence compound BN-GD-12 was adjusted to 74.25:24.75:1. The melted solid was ground into a powder to obtain premix PM8.

[0528] Preparation of premix PM9:

[0529] The first main compound PH-1, the second main compound NH-45 and the thermally activated delayed fluorescence compound BN-GD-12 were physically mixed in a weight ratio of 68.6:29.4:2, and rolled into a sample bottle and placed in a vacuum chamber. -3 Pa, heat to 280 ° C, maintain the temperature for 0.5 hours, cool to room temperature, and then put the sample bottle into the vacuum bottle again while maintaining the vacuum degree greater than 10 -3 Pa, heated to 280 ° C, maintained at this temperature for 0.5 hours, and then cooled to room temperature. The molten solid was ground into powder to obtain the premix PM9.

[0530] Preparation of premix PM10:

[0531] The preparation method for premix PM10 is the same as that for premix PM9, except that the first host compound PH-51 is used instead of the first host compound PH-1, and the second host compound NH-147 is used instead of the second host compound NH-45. The molten solid is ground into a powder to obtain premix PM10.

[0532] Preparation of comparative premix C-PM1:

[0533] The first main compound PH-51 and the second main compound NH-147 were physically mixed in a weight ratio of 70:30, and rolled into a sample bottle and placed in a vacuum chamber. -3 Pa, heat to 280 ° C, maintain the temperature for 0.5 hours, cool to room temperature, and then put the sample bottle into the vacuum bottle again while maintaining the vacuum degree greater than 10 -3 Pa, heated to 280°C, maintained at that temperature for 0.5 hours, and then cooled to room temperature. The molten solid was ground into powder to obtain comparative premix C-PM1.

[0534] The specific structures of the compounds used in the above premixes PM7 to PM10 and comparative premix C-PM1 are shown below:

[0535]

[0536] The composition of the present invention comprises a premix and a phosphorescent sensitizer. The premix is a three-component premix formed by premixing a first host compound, a second host compound, and a fluorescent compound. The premix exhibits high evaporation stability and can achieve stable device performance when applied to organic electroluminescent devices subjected to continuous evaporation deposition. Furthermore, the premix contained in the composition of the present invention can be used as a single evaporation source in the device preparation process, reducing the cost and complexity of the evaporation process. The following provides an example of a continuous evaporation device and its device data for demonstration:

[0537] Continuous evaporation device examples 1-1 to 1-5

[0538] First, a glass substrate with an 80nm thick indium tin oxide (ITO) anode was cleaned and then treated with oxygen plasma and UV ozone. After treatment, the substrate was dried in a glove box to remove moisture. The substrate was then mounted on a substrate holder and loaded into a vacuum chamber. The organic layers specified below were deposited under a vacuum of approximately 10 -8 The compound HT and the compound HI were co-evaporated to form a hole injection layer (HIL). The weight ratio of the compound HT and the compound HI was 97:3, and the thickness was 100 nm. Compound HT was used as the hole transport layer (HTL) with a thickness of Compound P-21 was used as electron blocking layer (EBL) with a thickness of Then, the premix PM1 (compound P-22, compound N-1-15 and compound BN-BD-2 in a weight ratio of 49:49:2) was placed in evaporation source 1, and the phosphorescence sensitizer Pt27 was placed in evaporation source 2 and co-evaporated to form an emitting layer (EML). The weight ratio of the premix PM1 and the phosphorescence sensitizer Pt27 was 88:12, and the thickness was 100 nm. Compound N-3-2 was used as the hole blocking layer (HBL) with a thickness of On the hole blocking layer, compound ET and 8-hydroxyquinoline-lithium (Liq) are co-evaporated as an electron transport layer (ETL), the weight ratio of compound ET and compound Liq is 40:60, and the thickness is Finally, evaporation Thickness of LiF as electron injection layer, and evaporated The device was then transferred back to the glove box and encapsulated with a glass cover and a moisture absorbent to complete Device Example 1-1. The above operation was repeated four times to obtain Device Examples 1-2 to 1-5.

[0539] Continuous evaporation device examples 2-1 to 2-5

[0540] Continuous evaporation device example 2-1 was prepared in the same manner as continuous evaporation device example 1-1, except that premix PM2 (compound P-22, compound N-1-15, and compound BN-BD-20 in a weight ratio of 49:49:2) was used in the light-emitting layer (EML) instead of premix PM1. This procedure was repeated four times to produce device examples 2-2 through 2-5.

[0541] Continuous evaporation device examples 3-1 to 3-5

[0542] Continuous evaporation device Example 3-1 was prepared in the same manner as Continuous evaporation device Example 1-1, except that premix PM3 (compound P-22, compound N-1-15, and compound BN-BD-34 in a weight ratio of 49:49:2) was used in the light-emitting layer (EML) instead of premix PM1. This procedure was repeated four times to produce devices Examples 3-2 through 3-5.

[0543] Continuous evaporation device examples 4-1 to 4-6

[0544] Continuous evaporation device example 4-1 was prepared in the same manner as continuous evaporation device example 1-1, except that premix PM4 (compound P-22, compound N-1-15, and compound BN-BD-1 in a weight ratio of 49:49:2) was used in the light-emitting layer (EML) instead of premix PM1. This procedure was repeated five times to produce device examples 4-2 through 4-6.

[0545] The detailed device layer structure and thickness are shown in the table below. For layers using more than one material, the different compounds are doped in the stated weight ratios.

[0546] Table 3 Partial device structures of device examples 1-1 to 1-5, device examples 2-1 to 2-5, device examples 3-1 to 3-5, and device examples 4-1 to 4-6

[0547]

[0548] The specific structure of the materials used in the device is shown below:

[0549]

[0550]

[0551] At 10 mA / cm 2 The CIE values of device examples 1-1 to 1-5, device examples 2-1 to 2-5, device examples 3-1 to 3-5 and device examples 4-1 to 4-6 were measured below, and the maximum emission wavelength (λ max ), full width at half maximum (FWHM) and external quantum efficiency (EQE). The relevant data are shown in Table 4.

[0552] Table 4 Device data

[0553]

[0554]

[0555] According to the above four groups of continuous evaporation device examples using the composition of the present invention as the light-emitting layer of the device, it can be seen that the maximum emission wavelength (λ max) varies by at most 1 nm, and the full width at half maximum (FWHM) varies by at most 2 nm. More importantly, the highest and lowest EQEs in the four groups of continuous evaporation devices differ by only 0.41%, 0.37%, 0.20%, and 0.07%, respectively, maintaining essentially equivalent EQEs. This demonstrates that the three-component premix contained in the composition of the present invention has high evaporation stability and can achieve stable device performance when applied to organic electroluminescent devices using continuous evaporation. Furthermore, the composition of the present invention requires only two evaporation sources to prepare a four-component light-emitting layer, reducing the cost and complexity of the evaporation process and possessing potential application value in industrial mass production.

[0556] In addition, the present invention also selected the coating layer produced by a single evaporation source of the pre-mixture PM10 prepared above for composition analysis, which once again verified the high evaporation stability of the three-component pre-mixture of the present invention. The details are as follows:

[0557] Preparation of PM10 coating layer:

[0558] The premixed PM10 was loaded into the evaporation source, and the distance between the evaporation source and the glass substrate was set to 35-60 cm. -7 Torr's case The premix PM10 is evaporated at a rate of 1000 nm and deposited onto a glass substrate to form a film with a thickness of 100 nm. coating layer.

[0559] The composition (%) of the PM10 coating layer was analyzed by HPLC, and the results are shown in Table 4-1. The HPLC analysis conditions used were: a C8 column, mobile phase: A: water; B: acetonitrile / tetrahydrofuran mixture (80 / 20, v / v), where A:B = 20:80 (v / v), gradient elution; detection wavelength: 232 nm.

[0560] Table 4-1 Composition ratio of premix in PM10 coating layer

[0561]

[0562] It can be seen from the data in Table 4-1 that the ratio of the three components in the PM10 coating layer is relatively close to the ratio of the three components in its premixture (68.6:29.4:2), which once again shows that the three-component premixture of the present invention has high evaporation stability.

[0563] In addition, the four sets of continuous evaporation device examples described above used four different premixes, PM1, PM2, PM3, and PM4. The premixes PM1, PM2, PM3, and PM4 contained compounds BN-BD-2, BN-BD-20, BN-BD-34, and BN-BD-1, respectively, as thermally activated delayed fluorescent compounds. The PM10 coating layer used compound BN-GD-12 as the thermally activated delayed fluorescent compound. Combining the evaporation temperatures of different materials in Table 2, the evaporation temperature of compound BN-BD-2 is 10°C lower than that of compound P-22, the evaporation temperature of compound BN-BD-20 is 22°C higher than that of compound P-22, the evaporation temperature of compound BN-BD-34 is 40°C lower than that of compound P-22, the evaporation temperature of compound BN-BD-1 is 24°C lower than that of compound P-22, and the evaporation temperature of compound BN-GD-12 is 39°C higher than that of compound PH-51 and 29°C higher than that of compound NH-147, respectively. In traditional two-component premixes, the evaporation temperatures of the two materials generally need to match to obtain a two-component premix with high evaporation stability. For example, the difference in evaporation temperature between the two materials should not be too large. In the three-component premix of the present invention, a three-component premix with high evaporation stability can also be obtained even when the evaporation temperature difference between the thermally activated delayed fluorescent compound and the two host materials is large. The thermally activated delayed fluorescent compound contained in the composition of the present invention breaks away from the general limitation of needing to match the evaporation temperature of two host materials, greatly increasing our choice of chemical structure of fluorescent materials.

[0564] The above data demonstrate that the three-component premixture comprising a first host compound, a second host compound, and a fluorescent compound exhibits high evaporation stability. When combined with a phosphorescent sensitizer, the composition of the present invention can be applied to an organic electroluminescent device subjected to continuous vapor deposition to achieve stable device performance. Furthermore, the premixture contained in the composition of the present invention can be used as a single evaporation source in the device preparation process, thereby reducing the cost and complexity of the vapor deposition process.

[0565] Furthermore, using the composition formed by combining the three-component premix with a phosphorescent sensitizer in the present invention to prepare devices not only reduces the cost and complexity of the evaporation process, but also achieves excellent device performance. The following device examples and their device data are provided to demonstrate this:

[0566] Blue organic electroluminescent devices

[0567] Device Example 1

[0568] First, a glass substrate with an 80nm thick indium tin oxide (ITO) anode was cleaned and then treated with oxygen plasma and UV ozone. After treatment, the substrate was dried in a glove box to remove moisture. The substrate was then mounted on a substrate holder and loaded into a vacuum chamber. The organic layers specified below were deposited under a vacuum of approximately 10 -8 The compound HT and the compound HI were co-evaporated to form a hole injection layer (HIL). The weight ratio of the compound HT and the compound HI was 97:3, and the thickness was 100 nm. Compound HT was used as the hole transport layer (HTL) with a thickness of Compound P-21 was used as electron blocking layer (EBL) with a thickness of Then, the premix PM5 (compound P-22, compound N-1-15 and compound BN-BD-2 in a weight ratio of 59:39:2) was placed in an evaporation source 1, and the phosphorescence sensitizer Pt27 was placed in an evaporation source 2 and co-evaporated to form an emitting layer (EML). The weight ratio of the premix PM5 and the phosphorescence sensitizer Pt27 was 88:12, and the thickness was 100 nm. Compound N-3-2 was used as the hole blocking layer (HBL) with a thickness of On the hole blocking layer, compound ET and 8-hydroxyquinoline-lithium (Liq) are co-evaporated as an electron transport layer (ETL), the weight ratio of compound ET and compound Liq is 40:60, and the thickness is Finally, evaporation Thickness of LiF as electron injection layer, and evaporated The device was then transferred back to the glove box and encapsulated with a glass cover and a moisture getter to complete the device.

[0569] Device Example 2

[0570] The implementation method of Device Example 2 is the same as that of Device Example 1, except that Premix PM6 (Compound P-22, Compound N-1-15 and Compound BN-BD-2 in a weight ratio of 39:59:2) is used instead of Premix PM5 in the light-emitting layer (EML).

[0571] Device Example 3

[0572] The implementation method of device example 3 is the same as that of device example 1, except that the premixture PM1 (the weight ratio of compound P-22, compound N-1-15 and compound BN-BD-2 is 49:49:2) is used instead of the premixture PM2 in the light-emitting layer (EML), and the phosphorescence sensitizer Pt11 is used instead of the phosphorescence sensitizer Pt27.

[0573] Device Example 4

[0574] The implementation of Device Example 4 is the same as that of Device Example 2, except that the phosphorescent sensitizer Pt11 is used instead of the phosphorescent sensitizer Pt27 in the emission layer (EML).

[0575] Device Comparative Example 1

[0576] The device comparative example 1 is implemented in the same manner as the device example 1, except that compound P-22, compound N-1-15, and compound Pt27 are co-evaporated in three different evaporation sources to serve as the light-emitting layer (EML). The weight ratio of compound P-22, compound N-1-15, and compound Pt27 is 52.8:35.2:12, and the thickness is

[0577] Device Comparative Example 2

[0578] The implementation method of device comparative example 2 is the same as that of device example 1, except that compound P-22, compound N-1-15 and compound BN-BD-2 are co-evaporated into three different evaporation sources to serve as the light-emitting layer (EML), the weight ratio of compound P-22, compound N-1-15 and compound BN-BD-2 is 59.4:28.6:12, and the thickness is

[0579] The detailed device layer structure and thickness are shown in the table below. For layers using more than one material, the different compounds are doped in the stated weight ratios.

[0580] Table 5 Device structures of device examples and comparative examples

[0581]

[0582]

[0583] The specific structure of the new materials used in the device is shown below:

[0584]

[0585] Figure 3 The emission spectra of the devices of Example 1, Comparative Example 1 and Comparative Example 2 after normalization are shown in FIG. Figure 3 We can find that the emission spectra of Example 1 and Comparative Example 2 are substantially overlapped, which indicates that the thermally activated delayed fluorescence compound BN-BD-2 is used as the luminescent material in the device of Example 1, rather than the phosphorescence sensitizer Pt27.

[0586] At 10 mA / cm 2 The CIE values of Examples 1-4 and Comparative Examples 1-2 were measured, and the maximum emission wavelength (λ max), full width at half maximum (FWHM) and external quantum efficiency (EQE). The relevant data are shown in Table 6.

[0587] Table 6 Device data

[0588]

[0589] Examples 1-4 and Comparative Example 2 both use the thermally activated delayed fluorescence compound BN-BD-2 as a luminescent material. Comparative Example 2 is an ordinary TADF device without a phosphorescent sensitizer. Compared with Comparative Example 2, Examples 1-4 can maintain a narrow half-width at half-peak that is substantially equivalent to that of the comparative example 2. Importantly, the EQE of Examples 1-4 is substantially improved by 178%-201%. Comparative Example 1 is a blue phosphorescent device, which has great advantages over the half-width and EQE of ordinary TADF devices. Although the half-width of Examples 1-4 is slightly wider than that of Comparative Example 1, the EQE is further improved compared to Comparative Example 1, which is also very rare. This shows that the use of the composition of the present invention to prepare devices can not only reduce the cost and complexity of the evaporation process, but also obtain better device performance with narrow half-width and high external quantum efficiency relative to ordinary TADF devices and blue phosphorescent devices. Therefore, it is proved that the composition of the present invention can be applied to organic electroluminescent devices to obtain excellent device performance.

[0590] In addition, in Example 1 and Example 2, the phosphorescence sensitizer Pt27 was used. The three-component materials in the premixture were the same, but the ratio of the first host compound to the second host compound was changed, and both exhibited excellent device performance. This shows that the first host compound and the second host compound in the three-component premixture contained in the composition of the present invention can be mixed in different proportions to form a premixture with high evaporation stability, thereby exhibiting excellent device performance. Example 2 and Example 4 used another phosphorescence sensitizer Pt11, and also achieved excellent device performance, which also shows that the premixture contained in the composition of the present invention can also have good adaptability for different phosphorescence sensitizers.

[0591] Green organic electroluminescent devices

[0592] Device Example 5

[0593] First, a glass substrate with an 80nm thick indium tin oxide (ITO) anode was cleaned and then treated with oxygen plasma and UV ozone. After treatment, the substrate was dried in a glove box to remove moisture. The substrate was then mounted on a substrate holder and loaded into a vacuum chamber. The organic layers specified below were deposited under a vacuum of approximately 10 -7Compound HI and compound HT1 were co-deposited as a hole injection layer (HIL, the weight ratio of compound HI and compound HT1 was 3:97), with a thickness of Compound HT1 was used as the hole transport layer (HTL) with a thickness of Compound PH-1 was used as an electron blocking layer (EBL) with a thickness of Then, the premix PM7 (compound PH-24, compound NH-144 and compound BN-GD-12 weight ratio is 73.5:24.5:2) is placed in an evaporation source 1, and the phosphorescent sensitizer GD100 is placed in an evaporation source 2 for co-evaporation as an emitting layer (EML, the weight ratio of the premix PM7 and the phosphorescent sensitizer GD100 is 94:6) with a thickness of Compound N-4-1 was used as the hole blocking layer (HBL) with a thickness of On the hole blocking layer, compound ET and 8-hydroxyquinoline-lithium (Liq) were co-evaporated as an electron transport layer (ETL, the weight ratio of compound ET and Liq was 40:60), with a thickness of Finally, evaporation Thickness of Liq as electron injection layer, and evaporated The device was then transferred back to the glove box and encapsulated with a glass cover and a moisture getter to complete the device.

[0594] Device Example 6

[0595] Device Example 6 was prepared in the same manner as Device Example 5, except that premix PM8 (compound PH-24, compound NH-144, and compound BN-GD-12 in a weight ratio of 74.25:24.75:1) was used instead of premix PM7 in the light-emitting layer (EML).

[0596] Device Example 7

[0597] Device Example 7 was prepared in the same manner as Device Example 5, except that premix PM9 (compound PH-1, compound NH-45 and compound BN-GD-12 in a weight ratio of 68.6:29.4:2) was used instead of premix PM7 in the light-emitting layer (EML).

[0598] Device Example 8

[0599] Device Example 8 was prepared in the same manner as Device Example 5, except that premixture PM10 (compound PH-51, compound NH-147, and compound BN-GD-12 in a weight ratio of 68.6:29.4:2) was used instead of premixture PM7 in the light-emitting layer (EML).

[0600] Device Comparative Example 3

[0601] The preparation method of device comparative example 3 is the same as that of device example 5, except that compound PH-24, compound NH-144, compound BN-GD-12, and phosphorescent sensitizer GD100 are placed in four different evaporation sources and co-evaporated to form an emitting layer (EML). The weight ratio of compound PH-24, compound NH-144, compound BN-GD-12, and phosphorescent sensitizer GD100 is 69:23:2:6, and the thickness is

[0602] Device Comparative Example 4

[0603] The preparation method of device comparative example 4 is the same as that of device example 6, except that compound PH-24, compound NH-144, compound BN-GD-12, and phosphorescent sensitizer GD100 are placed in four different evaporation sources and co-evaporated to form an emitting layer (EML). The weight ratio of compound PH-24, compound NH-144, compound BN-GD-12, and phosphorescent sensitizer GD100 is 69.75:23.25:1:6, and the thickness is

[0604] Device Comparative Example 5

[0605] The preparation method of device comparative example 5 is the same as that of device example 7, except that compound PH-1, compound NH-45, compound BN-GD-12, and phosphorescent sensitizer GD100 are placed in four different evaporation sources and co-evaporated to form an emitting layer (EML). The weight ratio of compound PH-1, compound NH-45, compound BN-GD-12, and phosphorescent sensitizer GD100 is 64.4:27.6:2:6, and the thickness is

[0606] Device Comparative Example 6

[0607] The preparation method of device comparative example 6 is the same as that of device example 8, except that the comparative premixture C-PM1 (compound PH-51, compound NH-147 weight ratio is 70:30), compound BN-GD-12, and phosphorescence sensitizer GD100 are placed in three different evaporation sources and co-evaporated to serve as the light-emitting layer (EML), the comparative premixture C-PM1, compound BN-GD-12, and phosphorescence sensitizer GD100 weight ratio is 92:2:6, and the thickness is

[0608] The structure and thickness of some device layers of device examples 5 to 8 and device comparative examples 3 to 6 are shown in Table 7. For layers using more than one material, the different compounds are doped in the weight ratios listed.

[0609] Table 7 Partial device structures of device examples and device comparative examples

[0610]

[0611] The new material structure used in the device is as follows:

[0612]

[0613] At 15 mA / cm 2 The CIE values of device examples 5 to 8 and device comparison examples 3 to 6 were measured, and the maximum emission wavelength (λ max ), full width at half maximum (FWHM) and external quantum efficiency (EQE) at 80 mA / cm 2 The lifespans LT97 (h) of the devices of Examples 5 to 8 and Comparative Examples 3 to 6 were measured. LT97 is the time it takes for the device brightness to decay to 97% of the initial brightness. The relevant data are shown in Table 8.

[0614] Table 8 Device data

[0615] Part Number CIE(x,y) <![CDATA[λ max [nm]]]> FWHM[nm] EQE (%) LT97(h) Example 5 0.355,0.635 548 34.0 25.7 25.5 Comparative Example 3 0.358,0.633 548 33.7 25.8 12.7 Example 6 0.335,0.648 543 38.6 26.3 26.0 Comparative Example 4 0.344,0.644 546 34.8 27.2 20.7 Example 7 0.333,0.647 539 43.2 25.5 30.8 Comparative Example 5 0.364,0.628 550 33.6 24.9 25.5 Example 8 0.354,0.636 548 34.4 25.7 16.2 Comparative Example 6 0.360,0.631 549 34.2 25.1 12.5

[0616] discuss:

[0617] Example 5 uses a composition of a premix PM7 (compound PH-24, compound NH-144, compound BN-GD-12) and a phosphorescent sensitizer as a light-emitting layer, wherein the premix is evaporated in a single evaporation source and the phosphorescent sensitizer is evaporated in another evaporation source. Comparative Example 3 also uses compound PH-24, compound NH-144, compound BN-GD-12 and a phosphorescent sensitizer as a light-emitting layer. The difference is that the light-emitting layer of Comparative Example 3 is formed by four-source co-evaporation (i.e., the four compounds are placed in four different evaporation sources and co-evaporated). As can be seen from the data in Table 8, Comparative Example 3 already has very high device performance. Compared with Comparative Example 3, Example 5 has a substantially equivalent narrow half-peak width and high EQE. Unexpectedly, the life of Example 5 is significantly increased by 100%. It can be seen that using the premix of the present invention to prepare devices can not only reduce the cost and complexity of the evaporation process, but also obtain better device comprehensive performance.

[0618] The three components (compound PH-24, compound NH-144, and compound BN-GD-12) in the premix PM8 used in Example 6 had the same material structure as PM7, with the ratios of the three components being varied. The difference between Comparative Example 4 and Example 6 lies in the number of evaporation sources. As shown in Table 8, while the half-value width of Example 6 is slightly wider and the EQE slightly lower than that of Comparative Example 4, it remains at a relatively high level. More importantly, the lifetime of Example 6 achieves an unexpectedly significant improvement of 26%. This demonstrates that the first host compound, the second host compound, and the thermally activated delayed fluorescence compound in the premix of the present invention can be mixed in varying proportions to form a premix with high evaporation stability, thereby exhibiting excellent device performance.

[0619] Example 7 uses a combination of premix PM9 (Compound PH-1, Compound NH-45, Compound BN-GD-12) and a phosphorescent sensitizer as the light-emitting layer. Comparative Example 5 also uses Compound PH-1, Compound NH-45, Compound BN-GD-12, and a phosphorescent sensitizer as the light-emitting layer, differing in the number of evaporation sources used. As shown in Table 8, Comparative Example 5 already exhibits very high device performance. While Example 7 exhibits a slightly wider half-value width compared to Comparative Example 5, it remains relatively narrow. More importantly, Example 7 achieves a similarly high EQE and an unexpectedly significant 21% improvement in lifetime. This demonstrates once again that the use of the premix of the present invention in devices not only reduces the cost and complexity of the evaporation process, but also achieves superior overall device performance.

[0620] In addition, Example 8 uses a composition of a premix PM10 (compound PH-51, compound NH-147, compound BN-GD-12) and a phosphorescent sensitizer as the light-emitting layer, and is also evaporated using two evaporation sources; Comparative Example 6 uses a comparative premix C-PM1 (compound PH-51, compound NH-147), compound BN-GD-12, and a phosphorescent sensitizer as the light-emitting layer, and is evaporated using three evaporation sources. As can be seen from the data in Table 8, Comparative Example 6 already has very high device performance. Compared with Comparative Example 6, Example 8 has a narrow half-peak width and high EQE that are basically equivalent to those of Comparative Example 6, while the lifespan is unexpectedly significantly increased by 30%. It can be seen that compared with the devices commonly used in the prior art that use a premix of a dual host and a light-emitting material to co-evaporate as the light-emitting layer, Example 8 of the present invention further reduces the evaporation source, reduces the cost and complexity of the evaporation process, and can provide better overall device performance. This result exceeded expectations and provides ideas for further commercial applications.

[0621] In summary, the present invention uses a composition composed of a specific three-component premix and a phosphorescence sensitizer to prepare a device, which not only reduces the cost and complexity of the evaporation process, but also utilizes the method of co-doping the phosphorescence sensitizer and the fluorescent compound in the dual host to achieve a good phosphorescence-sensitized thermally activated delayed fluorescence device effect, which can enable the device to maintain a narrow half-peak width and high EQE, unexpectedly improve the device life, and obtain better overall device performance, and has broad application prospects.

[0622] It should be understood that the various embodiments described herein are merely examples and are not intended to limit the scope of the present invention. Therefore, as will be apparent to those skilled in the art, the claimed invention may include variations of the specific embodiments and preferred embodiments described herein. Many of the materials and structures described herein can be replaced with other materials and structures without departing from the spirit of the present invention. It should be understood that the various theories regarding why the present invention works are not intended to be restrictive.

Claims

1. A composition comprising: A premix and a phosphorescent sensitizer, wherein the premix comprises a first host compound, a second host compound and a fluorescent compound; wherein the triplet energy levels of the first host compound, the second host compound, and the phosphorescence sensitizer are all higher than the triplet energy level of the fluorescent compound; wherein the first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.; wherein the second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.; The absolute value of the difference between T1 and T2 is less than or equal to 20°C. 2 . The composition according to claim 1 , wherein the fluorescent compound is a P-type delayed fluorescent compound or an E-type delayed fluorescent compound; preferably, the fluorescent compound is an E-type delayed fluorescent compound.

3. The composition of claim 1 or 2, wherein the T1 is 150°C to 350°C, and the T2 is 150°C to 350°C; Preferably, the T1 is 200°C to 350°C, and the T2 is 200°C to 350°C. 4 . The composition according to claim 1 , wherein the fluorescent compound has an evaporation temperature T3 of 150° C. to 400° C.; preferably, T3 is 180° C. to 350° C.

5. The composition according to claim 1 or 2, wherein the absolute value of the difference between T1 and T2 is less than or equal to 10°C.

6. The composition of claim 4, wherein the absolute value of the difference between T3 and T1, or the absolute value of the difference between T3 and T2, is less than or equal to 80°C; preferably, the absolute value of the difference between T3 and T1, or the absolute value of the difference between T3 and T2, is less than or equal to 60°C; more preferably, the absolute value of the difference between T3 and T1, or the absolute value of the difference between T3 and T2, is less than or equal to 50°C.

7. The composition of claim 2, wherein the E-type delayed fluorescence compound has a structure represented by Formula 1: In formula 1, Ring A, Ring B, Ring C, Ring D, and Ring E are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms or an unsaturated heterocyclic ring having 3 to 30 carbon atoms; Y1, E1 and E2 are each independently selected from B, N, P, P=O, P=S, As, As=O, As=S, SiR' or GeR'; T1 to T 10 Each independently selected from C, CR z or N; L1, L2, L3, L4 are each selected from the group consisting of a single bond, O, S, Se, BR v or NR v ; a, b, c, d, e are each independently selected from 0 or 1; R z Each occurrence of the same or different means mono-, poly- or no-substitution; R v , R z and R', at each occurrence, is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkyl having 2 to 30 carbon atoms, -alkynyl groups having 20 to 30 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amino groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, -BR"R", and combinations thereof; R" is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; Adjacent substituent R v , R z , R' and R" can be optionally linked to form a ring.

8. The composition of claim 2, wherein the E-type delayed fluorescence compound has a structure represented by one of Formula 1-1 to Formula 1-4: in, a, b, c, d, e, and f are each independently selected from 0 or 1; E1 and E2 are each independently selected from B or N; L1, L2, L3, L4 are each the same or different and are selected from a single bond, O, S, BR v or NR v ; L5, L6 are each identically or differently selected from a single bond, O, S or NR v ; R z Each occurrence of the same or different means mono-, poly- or no-substitution; R v , R z Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkyl having 2 to 2 alkynyl groups having 0 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amino groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, -BR"R", and combinations thereof; R" is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; Adjacent substituent R v , R z and R" can be optionally linked to form a ring.

9. The composition of claim 1, wherein the fluorescent compound is selected from the group consisting of Compound BN-BD-1 to Compound BN-BD-53, Compound BN-RD-1 to Compound BN-RD-22, Compound BN-GD-1 to Compound BN-GD-51, Compound BN-GD-53 to Compound BN-GD-63, and Compound FD-1-1 to Compound FD-1-53: Optionally, the hydrogen in compounds BN-BD-1 to BN-BD-53, compounds BN-RD-1 to BN-RD-22, compounds BN-GD-1 to BN-GD-51, compounds BN-GD-53 to BN-GD-63, and compounds FD-1-1 to FD-1-53 can be partially or fully substituted with deuterium.

10. The composition according to claim 1, wherein the maximum photoluminescence emission wavelength of the fluorescent compound is 450 nm to 500 nm; Preferably, the maximum photoluminescence emission wavelength of the fluorescent compound is 450 nm to 470 nm; More preferably, the maximum photoluminescence emission wavelength of the fluorescent compound is 455 nm to 465 nm.

11. The composition according to claim 1, wherein the maximum emission wavelength of the photoluminescence spectrum of the fluorescent compound is 520 nm to 650 nm; Preferably, the maximum emission wavelength of the photoluminescence spectrum of the fluorescent compound is 520 nm to 630 nm; More preferably, the maximum emission wavelength of the photoluminescence spectrum of the fluorescent compound is 520 nm to 580 nm.

12. The composition of claim 1, wherein the full width at half maximum of the photoluminescence of the fluorescent compound is less than 45 nm; Preferably, the full width at half maximum of the fluorescent compound is less than 35 nm; More preferably, the full width at half maximum of the fluorescent compound is less than 30 nm.

13. The composition of claim 1, wherein the phosphorescence sensitizer has M(L a ) m (L b ) n (L c ) q The general formula of The M is selected from metals with a relative atomic mass greater than 40; preferably, the metal M is selected from the group consisting of Cu, Ag, Au, Zn, Ru, Rh, Pd, Os, Ir and Pt; Ligand L a 、L b and L c are respectively the first ligand, the second ligand and the third ligand coordinated with the metal M, the ligand L a 、L b and L c Can be the same or different; Ligand L a 、L b and L c can optionally be linked to form multidentate ligands; m is 1, 2 or 3; n is 0, 1 or 2; q is 0, 1 or 2; the sum of m, n, q is equal to the oxidation state of metal M; when m is greater than or equal to 2, multiple L a Can be the same or different; when n is 2, the two L b Can be the same or different; when q is 2, the two L c Can be the same or different; Ligand L a It has the structure shown in Formula 2: Ring F and Ring G are identical or different at each occurrence and are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 1 to 30 carbon atoms, or a combination thereof; X1 and X2 are each selected, identically or differently, from C or N; K1 and K2 are each independently selected from a single bond, O or S; A1 is selected from single bond, O, S, Se, (SiR q R q ) y , PR q ,NR q , (CR q R q ) y , a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof; y is the same or different when each occurs and is selected from 1, 2, 3, 4 or 5; R f and R g Each occurrence of the same or different means mono-, poly- or no-substitution; R f and R g Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; Adjacent substituent R f and R g can optionally be linked to form a ring; Ligand L b and L c the same or different at each occurrence selected from monoanionic bidentate ligands; Preferably, the ligand L b and L c Each occurrence is identically or differently selected from the group consisting of: in, R a and R b Each occurrence is identical or different and represents mono-, poly-, or unsubstituted; X b Each occurrence is identical or different and is selected from the group consisting of: O, S, Se, NR N1 and CR C1 R C2 ; X c and X d Each occurrence is identically or differently selected from the group consisting of: O, S, Se and NR N2 ; R a , R b , R c , R N1 , R N2 , R C1 and R C2 Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; Adjacent substituent R a , R b , R c , R N1 , R N2 , R C1 and R C2 Can optionally be linked to form a ring.

14. The composition of claim 13, wherein the ligand L a Having a structure represented by Formula 2-1 or Formula 2-2: In formula 2-1, ring F1 is selected from an unsaturated heterocyclic ring having 1 to 30 carbon atoms; In formula 2-2, ring F2 and ring F3 are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof; Ring F2 and ring F3 are fused via H1 and H2; X1 and X2 are each independently selected from C or N, and X1 and X2 are different; H1 and H2 are each identically or differently selected from C or N; K1 and K2 are each independently selected from a single bond, O or S; G is selected from CR in the same or different way each time it occurs g or N; R f1 , R f2 and R f3 Each occurrence represents identically or differently monosubstituted, polysubstituted or unsubstituted; R, R g , R f1 , R f2 and R f3 Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; Adjacent substituents R, R g , R f1 , R f2 and R f3 Can optionally be linked to form a ring.

15. The composition of claim 1, wherein the phosphorescent sensitizer has a structure represented by one of Formula 3-1 to Formula 3-24: in, A2 is selected, at each occurrence, the same or different, from a single bond, O, S, Se, (SiRqRq)y, PRq, NRq, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof; y is selected, at each occurrence, the same or different, from 1, 2 or 3; U1-U 20 Each occurrence is identically or differently selected from CRn or N; Ring F3 is identically or differently selected at each occurrence from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof; Q is selected, identically or differently, from O, S or Se at each occurrence; m is selected from 0, 1, 2 or 3, the same or different at each occurrence; Ru, Rf3 each time appear, the same or different, represents single substitution, multiple substitution or no substitution; R, R N Rq, Ru, Rn, Rf3, Ra, Rb and Rc are each identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkyl having 2 to 20 carbon atoms alkenyl, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphino, and combinations thereof; Adjacent substituents R, R N , R q , R u , R n and R f3 can optionally be linked to form a ring; Preferably, the phosphorescent sensitizer has a structure represented by Formula 3-1 or Formula 3-2; More preferably, the R has a structure represented by Formula 4: In formula 4, Ring M and Ring W are identically or differently selected at each occurrence from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof; X5-X8 are each identically or differently selected from C or N; "*" indicates the connection position of the formula 4; R m Each occurrence represents identically or differently monosubstituted, polysubstituted or unsubstituted; R w Each occurrence is identical or different, indicating mono- or polysubstitution; R m and R w Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; Adjacent substituent R m , R w Can optionally be linked to form a ring.

16. The composition of claim 1, wherein The phosphorescence sensitizer has Ir(L a ) m (L b ) 3-m The general structure of the present invention is represented by the formula Ma: in, m is selected from 1, 2 or 3; when m is selected from 1, two L b Same or different; when m is selected from 2 or 3, multiple L a Same or different; Ring F is selected from heteroaromatic rings having 5 to 30 ring atoms; Ring G is selected from an aromatic ring having 6 to 30 ring atoms, a heteroaromatic ring having 5 to 30 ring atoms, or a combination thereof; U1 to U8 are selected from CR in the same or different ways each time they appear. n or N; R f and R g Each occurrence of the same or different means mono-, poly- or no-substitution; R f , R g and R n Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; Adjacent substituent R f , R g and R n can optionally be linked to form a ring; Preferably, the ring F is selected from any one of the following structures: The ring G is selected from any one of the following structures: in, Q' is selected from O, S, Se, NR Q , CR Q R Q , SiR Q R Q and GeR Q R Q When there are multiple R Q When multiple R Q Same or different; R f , R g Each occurrence is the same or different and represents mono-, poly-, or unsubstituted; when multiple R f or R g When the R f or R g Same or different; R f , R g , R Q Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted an alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylgermanyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a mercapto group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; Adjacent substituent R f , R g , R Q can optionally be linked to form a ring; Among them, "#" indicates the position connected to the metal Ir, Indicates the location of connection with ring G; More preferably, the ring F is selected from The ring G is selected from 17. The composition of claim 1, wherein the phosphorescence sensitizer is selected from the group consisting of BD1 to BD18, RD1 to RD209, and GD1 to GD177: Or the phosphorescent sensitizer has Pt(L a )(L b ) represents a structure where L a and L b are the first ligand and the second ligand coordinated with the metal Pt, respectively. a Choose from L a 1-1 to L a 1-25 and L a 2-1 to L a Groups of 2-10: The L a 1-1 to L a 1-25 and L a 2-1 to L a The "#" in the 2-10 structure indicates that b The location of the connection; the L b Choose from L b 1-1 to L b 1-8 and L b 2-1 to L b Groups consisting of 2-24 members: The L b 1-1 to L b 1-8 and L b 2-1 to L b The "#" in the 2-24 structure indicates that b The location of the connection; Preferably, the phosphorescent sensitizer is selected from the group consisting of Pt1 to Pt96, wherein the Pt1 to Pt96 have Pt(L a )(L b ) represents a structure, wherein L a and the L b The corresponding structures are selected from the following table: 。 18. The composition of claim 1, wherein the first host compound has a structure represented by one of Formula 5 to Formula 7: In Formula 5, Z1 to Z3 are selected from CR4 or N at each occurrence, the same or different, and at least one of Z1 to Z3 is N; L is identically or differently selected at each occurrence from the group consisting of a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, and combinations thereof; In Formula 6 and Formula 7, Z4 is selected from CR4 or N at each occurrence, the same or different, and at least one Z4 is N; Z is selected from O or S in the same or different manner at each occurrence; R1-R4 are each identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted substituted or unsubstituted alkynyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amino groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, cyano groups, isocyano groups, hydroxyl groups, mercapto groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof; Adjacent substituents R4 can optionally be linked to form a ring; Preferably, the first host compound is selected from the group consisting of Compound N-1-1 to Compound N-1-60, Compound N-2-1 to Compound N-2-35, Compound N-3-1 to Compound N-3-9 and Compound N-4-1 to Compound N-4-34, Compound NH-1 to Compound NH-224: in, Optionally, the hydrogen in the structures of Compound N-1-1 to Compound N-1-53, Compound N-1-58, Compound N-2-1 to Compound N-2-32, Compound N-3-1 to Compound N-3-7 and Compound N-4-1 to Compound N-4-34, Compound NH-1 to Compound NH-224 can be partially or completely replaced by deuterium.

19. The composition of claim 1, wherein the second host compound has a structure represented by Formula 8, Formula 9, or Formula 10: L 11 is selected from a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof; Ar 11 is selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted amino group having 0 to 30 carbon atoms, or a combination thereof; G' is selected from C(R g ')2、NR g ', O or S; V is selected, identically or differently, at each occurrence from C, CR6 or N; Each occurrence of R6 is the same or different and represents mono-, poly- or non-substituted; R6, R g 'Each occurrence is identically or differently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkyl having 2 to 20 carbon atoms alkenyl, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphino, and combinations thereof; Adjacent substituents R6 can optionally be linked to form a ring; Preferably, the second host compound has a structure represented by Formula 8-1 or Formula 8-2: L 11 , L 12 is selected from a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 3 to 30 carbon atoms, or a combination thereof; Ar 11 is selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted amino group having 0 to 30 carbon atoms, or a combination thereof; Each occurrence of R6 is the same or different and represents mono-, poly- or non-substituted; R6 is selected, at each occurrence, identically or differently, from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkyl having 2 to 20 carbon atoms, alkenyl, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphino, and combinations thereof; Adjacent substituents R6 can optionally be linked to form a ring; More preferably, the second host compound is selected from the group consisting of Compound P-1 to Compound P-66, and Compound PH-1 to Compound PH-223: in, Optionally, hydrogen in the structures of Compound P-1 to Compound P-23, Compound P-27 to Compound P-66, and Compound PH-1 to Compound PH-223 can be partially or completely replaced by deuterium.

20. Use of the composition according to any one of claims 1 to 19 in an organic electroluminescent device.

21. An organic electroluminescent device comprising: anode, cathode, and an organic layer disposed between the anode and the cathode, the organic layer comprising the composition according to any one of claims 1 to 19; The composition comprises a premix and a phosphorescent sensitizer, wherein the premix comprises a first host compound, a second host compound and a fluorescent compound; wherein the triplet energy levels of the first host compound, the second host compound, and the phosphorescence sensitizer are all higher than the triplet energy level of the fluorescent compound; wherein the first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.; wherein the second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.; The absolute value of the difference between T1 and T2 is less than or equal to 20°C. 22 . The organic electroluminescent device according to claim 21 , wherein the organic layer is a light-emitting layer, the first host compound and the second host compound are host materials, and the fluorescent compound is a light-emitting material.

23. An organic electroluminescent device as claimed in claim 21 or 22, wherein the device emits blue light, green light or white light.

24. The organic electroluminescent device according to claim 22, wherein the weight ratio of the first host compound and the second host compound to the total weight of the light-emitting layer material is 65%-98.9%, the weight ratio of the phosphorescent sensitizer to the total weight of the light-emitting layer material is 1%-30%, and the weight ratio of the fluorescent compound to the total weight of the light-emitting layer material is 0.1%-5%; Preferably, the weight ratio of the first host compound and the second host compound to the total weight of the light-emitting layer material is 82%-94.5%, the weight ratio of the phosphorescent sensitizer to the total weight of the light-emitting layer material is 5%-15%, and the weight ratio of the fluorescent compound to the total weight of the light-emitting layer material is 0.5%-3%; More preferably, the weight of the first host compound and the second host compound accounts for 86.5%-91.5% of the total weight of the light-emitting layer material, the weight of the phosphorescent sensitizer accounts for 8%-12% of the total weight of the light-emitting layer material, and the weight of the fluorescent compound accounts for 0.5%-1.5% of the total weight of the light-emitting layer material.

25. A method for preparing an organic electroluminescent device, wherein the organic electroluminescent device comprises an anode, a cathode, and an organic layer disposed between the anode and the cathode, the organic layer comprising the composition according to any one of claims 1 to 19, the method comprising: Step 1: providing a substrate and arranging the anode thereon; Step 2: pre-mixing the first host compound, the second host compound and the fluorescent compound to form the pre-mixture, and placing the pre-mixture in an evaporation source 1 in a high vacuum deposition tool; The phosphorescence sensitizer is placed in the evaporation source 2 in the high vacuum deposition tool; -6 co-evaporating the premixture in the evaporation source 1 and the phosphorescent sensitizer in the evaporation source 2 at a rate of 0.2-2 angstroms / second in a high vacuum deposition tool of 1000 Torr or lower, and co-evaporating the premixture in the evaporation source 1 and the phosphorescent sensitizer in the evaporation source 2 on a surface positioned a certain distance from the evaporated premixture and phosphorescent sensitizer to form the organic layer; wherein the triplet energy levels of the first host compound, the second host compound, and the phosphorescence sensitizer are all higher than the triplet energy level of the fluorescent compound; wherein the first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.; wherein the second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.; The absolute value of the difference between T1 and T2 is less than or equal to 20°C; Step 3: Depositing the cathode on the organic layer.

26. A premix comprising a first host compound, a second host compound and a fluorescent compound; in, The triplet energy levels of the first host compound and the second host compound are both higher than the triplet energy level of the fluorescent compound; The first host compound has an evaporation temperature T1, and T1 is 100° C. to 400° C.; The second host compound has an evaporation temperature T2, and T2 is 100° C. to 400° C.; The absolute value of the difference between T1 and T2 is less than or equal to 20°C.

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