Organic light-emitting device

Abstract

Disclosed is an organic electroluminescent device in which a first organic layer and a second organic layer are provided between an anode and a cathode, the HOMO energy levels and giant surface potential (GSP) of the first and second organic layers having the following relationship: HOMO first organic layer-HOMO second organic layer > = 0.05, and GSP first organic layer-GSP second organic layer > = 30 mV / nm, GSP first organic layer > 0, gSP of the second organic layer is less than 0. Therefore, the obtained organic light-emitting device has interface charge distribution with coordinated regulation and control, and the maximum capacitance of the device is remarkably reduced while electrons are efficiently blocked and charge balance recombination in a light-emitting layer is promoted, so that stable improvement of driving efficiency and optimization of capacitance are realized, and the performance of the device is remarkably improved. The invention further discloses electronic equipment comprising the organic light-emitting device.

Description

TECHNICAL FIELD

[0001] The present application relates to an organic electroluminescent device. More particularly, it relates to an organic electroluminescent device comprising a bifunctional layer structure satisfying a specific energy level and surface potential relationship. BACKGROUND

[0002] With the continuous development of OLED technology, OLED has been widely used in the fields of display and lighting due to its low cost, low power consumption, high brightness, wide viewing angle and thinness. At the same time, the continuous optimization of device performance in the industry, especially the reduction of device capacitance, has become a key challenge to realize high refresh rate and low power consumption display. High capacitance not only increases the load and power consumption of driving, causing heat and efficiency loss, but also causes signal delay, brightness unevenness and crosstalk phenomenon during dynamic driving, which seriously restricts the performance of high-resolution and high-refresh-rate display panels.

[0003] In order to fundamentally regulate the capacitance, the industry has begun to focus on the microelectrical properties of materials and interfaces, especially the giant surface potential (Giant Surface Potential Slope, abbreviated as GSPS or GSP). GSP refers to the built-in potential gradient along the thickness direction formed by the intrinsic dipole orientation of organic semiconductor thin film, interface charge transfer or band bending, with the unit of mV / nm, and the sign (positive / negative) represents the direction of potential change, and the size reflects the electric field strength.

[0004] When an organic molecule has an asymmetric charge distribution or a permanent dipole moment, it will often undergo directional arrangement during film formation (such as vacuum evaporation), so that the molecular dipole will present a consistent orientation on a macroscopic scale. This collective orientation will cause the formation of a net electric dipole layer inside the film, thereby forming a stable potential gradient throughout the film thickness. Even if the surface of the molecule appears to be symmetrical, at the interface with different electrodes or functional layers, due to the Fermi level alignment and charge transfer, interface band bending will also occur, thereby generating space charge and built-in electric field in the region near the interface of the thin film. In addition, the growth morphology, crystal orientation and π-π stacking mode of the thin film may further induce or amplify this macroscopic polarization effect.

[0005] Therefore, GSP is a universal intrinsic property of organic semiconductor thin film - it is essentially a molecular scale characteristic (chemical structure, dipole moment) that presents a necessary electrostatic performance in the macroscopic condensed state through interface and ordering process. It is this universality that makes GSP a key physical parameter that can be systematically measured, designed and used for device performance regulation.

[0006] In OLED devices, GSP can actively regulate the injection and distribution of carriers - positive GSP promotes hole injection, and negative GSP inhibits injection; by designing the matching relationship of GSP in adjacent functional layers, the interface charge accumulation can be optimized, which can improve the recombination efficiency and significantly reduce the capacitance, which is a key interface engineering parameter to realize high-performance and low-power consumption devices.

[0007] Organic electroluminescent devices have been widely used in the field of display and lighting. In order to improve the luminous efficiency and working stability of the device, an electron blocking layer is usually provided between the light-emitting layer and the hole transport layer to inhibit the leakage of electrons to the hole transport region, thereby promoting the efficient recombination of electrons and holes in the light-emitting layer. However, in the traditional device design, the optimization of the electron blocking layer mainly focuses on energy level matching and carrier regulation, often without considering the control of the device capacitance simultaneously. The capacitance problem of OLED devices under high-frequency driving is increasingly prominent, and the higher parasitic capacitance can lead to increased dynamic power consumption, reduced response speed, and may cause signal delay and heating problems, which has become an important constraint factor for the development of high-resolution and high-refresh-rate display technology. In recent years, the research community has gradually recognized that the surface potential characteristics at the material interface, such as GSP, have a key influence on the charge injection, transport, and charge accumulation behavior at the interface.

[0008] The solution proposed in patent application CN118742077A is to introduce a specific first layer between the two light-emitting units in a series structure, and the GSP of this layer is opposite in sign to the GSP of the adjacent layers, preferably negative. By designing this first layer, a high density of positive interface fixed charges can be induced near the interface between it and the adjacent layers. This charge effect is beneficial to promoting the injection of electrons generated from the P-type charge generation layer to the first light-emitting unit, thereby achieving lower driving voltage and higher efficiency without relying on traditional N-type charge generation layers containing alkali metal compounds.

[0009] Patent application CN118265344A is committed to improving the problem of excessively high capacitance in phosphorescent OLED devices, especially blue and green devices, by introducing a "counter potential layer" with opposite sign and large surface potential slope inside the device to partially offset the built-in electric field generated by the dipole moment arrangement of the emission layer, thereby reducing the overall device capacitance and improving image quality degradation caused by RC delay differences. The counter potential layer of this application is integrated into the internal structure of the OLED device, such as being provided in the hole transport region (such as between the hole transport layer and the emission layer), in the emission auxiliary layer, or directly in contact with the emission layer. It should be noted that in addition to the large surface potential, energy level matching is also a key factor affecting the charge injection, transport, and capacitance characteristics of the device, but this content is not discussed as a core control means in this application.

[0010] Therefore, there is an urgent need to develop an innovative device structure that can effectively achieve electron blocking and ensure high luminous efficiency while significantly reducing the device capacitance, thereby meeting the application requirements of next-generation high-performance, low-power OLED devices. Summary of the Invention

[0011] The present invention aims to provide an organic electroluminescent device that effectively reduces the capacitance and improves the performance of the device by introducing a bilayer functional structure with a specific energy level and surface potential relationship.

[0012] According to one embodiment of the present invention, an organic electroluminescent device is disclosed, comprising:

[0013] anode,

[0014] cathode,

[0015] and the first organic layer and the second organic layer disposed between the anode and the cathode.

[0016] Wherein, the HOMO energy level of the first organic layer is HOMO 第一有机层 The giant surface potential is GSP 第一有机层 The HOMO energy level of the second organic layer is HOMO. 第二有机层 The giant surface potential is GSP 第二有机层 HOMO 第一有机层 -HOMO 第二有机层 ≥0.05, and GSP 第一有机层 -GSP 第二有机层 ≥30mV / nm, GSP 第一有机层 >0, GSP 第二有机层 <0.

[0017] According to one embodiment of the present invention, an electronic device comprising the organic electroluminescent device is also disclosed.

[0018] The organic electroluminescent device disclosed in this invention comprises a first organic layer and a second organic layer, wherein the giant surface potential (GSP) and HOMO energy levels of the first organic layer and the second organic layer respectively satisfy: HOMO 第一有机层 -HOMO 第二有机层 ≥0.05, and GSP 第一有机层 -GSP 第二有机层 ≥30mV / nm, GSP 第一有机层 >0, GSP 第二有机层<0; The resulting organic electroluminescent device achieves a significant reduction in maximum capacitance while maintaining high device efficiency. This invention demonstrates that the dual synergistic design of GSP and HOMO energy levels between specific organic layers in an organic electroluminescent device can simultaneously achieve a significant reduction in capacitance and optimization of efficiency, providing a new approach for the structural design and performance improvement of OLED devices. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the organic light-emitting device used for giant surface potential (GSP) testing in this paper.

[0020] Figure 2 This is a schematic diagram of another organic light-emitting device disclosed herein. Detailed Implementation

[0021] OLEDs can be fabricated on various substrates, such as glass, plastic, and metal. An OLED device may include a substrate, an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode. The device can be fabricated by sequentially depositing the described layers. The properties and functions of each layer, as well as exemplary materials, are described in more detail in columns 6-10 of U.S. Patent 7,279,704B2, the entire contents of which are incorporated herein by reference.

[0022] Each of these layers has numerous examples. For instance, a flexible and transparent substrate-anode combination is disclosed in U.S. Patent No. 5,844,363, which is incorporated herein 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 herein 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 herein 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 herein by reference in its entirety. Examples of cathodes are disclosed in U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated herein by reference in their entirety. These cathodes comprise composite cathodes having a thin metal layer, such as Mg:Ag, overlaid with a 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, which are also incorporated herein by reference in their entirety. Examples of implantation layers are provided in U.S. Patent Application Publication No. 2004 / 0174116, which is also incorporated herein by reference in its entirety. A description of protective layers can be found in U.S. Patent Application Publication No. 2004 / 0174116, which is also incorporated herein by reference in its entirety.

[0023] The layered structure described above is provided through non-limiting embodiments. The functionality of an OLED can be achieved by combining the various layers described above, or some layers can be omitted entirely. It may 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 may include several sublayers. For example, a light-emitting layer may have two different light-emitting materials to achieve a desired emission spectrum.

[0024] In one embodiment, an OLED can be described as having an "organic layer" disposed between a cathode and an anode. This organic layer may include one or more layers.

[0025] OLEDs also require an encapsulation layer, which can be placed above the cathode to protect against harmful substances from the environment, such as moisture and oxygen. Any material capable of providing encapsulation 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 7,968,146B2, the entire contents of which are incorporated herein by reference.

[0026] Devices manufactured according to embodiments of the present invention can be incorporated into a variety of consumer products having one or more electronic component modules (or units). Some examples of such consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for indoor or outdoor lighting and / or signaling, head-up displays, fully or partially transparent displays, flexible displays, smartphones, tablet computers, phablets, wearable devices, smartwatches, laptop computers, digital cameras, portable camcorders, viewfinders, microdisplays, 3D displays, vehicle displays, and taillights.

[0027] The materials and structures described in this article can also be used in other organic electronic devices listed above.

[0028] As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. When the first layer is described as being "disposed" on the second layer, the first layer is positioned further from the substrate. Unless it is specified that the first layer "contacts" the second layer, other layers may exist between the first and second layers. For example, even if various organic layers exist between the cathode and anode, the cathode may still be described as being "disposed" on the anode.

[0029] As used herein, “solution-handleable” means capable of being dissolved, dispersed or transported in and / or deposited from a liquid medium in the form of a solution or suspension.

[0030] When a ligand is believed to directly contribute to the photosensitivity of the emitting material, the ligand can be called "photosensitive." When a ligand is believed not to contribute to the photosensitivity of the emitting material, the ligand can be called "auxiliary," but auxiliary ligands can alter the properties of photosensitivity ligands.

[0031] 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: P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is generated by triplet-triplet annihilation (TTA).

[0032] On the other hand, E-type delayed fluorescence does not depend on the collision of two triplet states, but rather on the transition between triplet and singlet excited states. Compounds capable of producing E-type delayed fluorescence need to have a very small singlet-triple gap to facilitate the transition between energy states. Thermal energy can activate the transition from triplet to singlet. This type of delayed fluorescence is also called thermally activated delayed fluorescence (TADF). A significant characteristic of TADF is that the delayed component increases with increasing temperature. If the reverse system crossover (RISC) rate is fast enough to minimize the nonradiative decay from the triplet state, the fraction of singlet excited states that are refilled can reach 75%. The total singlet fraction can be 100%, far exceeding the 25% spin statistics of electrogenerated excitons.

[0033] E-type delayed fluorescence can be observed in excited complex systems or single compounds. Unbound by theory, it is believed that E-type delayed fluorescence requires the luminescent material to have a small singlet-triple bandgap (ΔE). S-T Organic, nonmetallic donor-acceptor luminescent materials may be able to achieve this. The emission of these materials is typically characterized as donor-acceptor charge transfer (CT) emission. Spatial separation of the HOMO and LUMO in these donor-acceptor compounds usually produces small ΔE. S-T These states can include CT states. Typically, donor-acceptor luminescent materials are constructed by linking an electron donor moiety (e.g., an amino or carbazole derivative) with an electron acceptor moiety (e.g., an N-containing six-membered aromatic ring).

[0034] Heteroalkyl – as used herein, a heteroalkyl group comprises one or more carbon atoms in an alkyl chain that are replaced by heteroatoms selected from the group consisting of nitrogen, oxygen, sulfur, selenium, phosphorus, silicon, germanium, and boron atoms. The heteroalkyl group can 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. Examples of heteroalkyl groups include 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. Additionally, heteroalkyl groups may optionally be substituted.

[0035] Alkenyl – as used herein, encompasses straight-chain, branched, and cyclic olefinic groups. An alkenyl group can be an alkenyl group containing 2 to 20 carbon atoms, preferably an alkenyl group having 2 to 10 carbon atoms. Examples of alkenyl groups include vinyl, 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, cyclohepttrienyl, cyclooctenyl, cyclooctatetraenyl, and norbornyl. In addition, the alkenyl group can be optionally substituted.

[0036] Alkynyl – as used herein, encompasses straight-chain alkynyl groups. An alkynyl group can be one containing 2 to 20 carbon atoms, preferably 2 to 10 carbon atoms. Examples of alkynyl groups include ethynyl, propynyl, propynyl, 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, propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, and phenylethynyl are preferred. Furthermore, the alkynyl group may be optionally substituted.

[0037] Aryl or aromatic group – as used herein, both non-fused and fused systems are considered. 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, fenene, fluorene, pyrene, etc. 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'-methyldiphenyl, 4”-tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesitylene, and m-tetraphenyl. Additionally, the aryl group may optionally be substituted.

[0038] Heterocyclic groups or heterocycles – as used herein, consider non-aromatic cyclic groups. 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, oxygen, sulfur, selenium, silicon, phosphorus, germanium, and boron atoms. 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 ethylene oxide, oxetane, tetrahydrofuranyl, tetrahydropyranyl, dioxopentacyclic, dioxahexacyclic, acridineyl, dihydropyrroleyl, tetrahydropyrroleyl, piperidinyl, oxazolidinyl, morpholinyl, piperazineyl, oxetane-heptanetrienyl, thioheptanetrienyl, azirane-heptanetrienyl, and tetrahydrothiorroleyl. In addition, the heterocyclic group can be optionally substituted.

[0039] Heteroaryl – as used herein – can be a non-fused or fused heteroaryl group comprising 1 to 5 heteroatoms, wherein at least one heteroatom is selected from the group consisting of nitrogen, oxygen, sulfur, selenium, silicon, phosphorus, germanium, and boron. Isoaryl also refers to heteroaryl. Heteroaryl can be a heteroaryl having 3 to 30 carbon atoms, preferably a heteroaryl having 3 to 20 carbon atoms, and more preferably a heteroaryl having 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolecarbazole, pyridineindole, pyrrolopyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxtriazole, dioxazole, thiadiazol, pyridine, pyrazine, pyrazine, triazine, oxazine, oxthiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzoisoxazole, benzothiazole, quinoline, isoquinoline Phosphine, cyclophosphine, quinazoline, quinoxaline, naphthidine, phthalazine, pteridine, xanthan, acridine, phenazine, phenothiazine, benzofuranopyridine, furanodipyridine, benzothiophenopyridine, thiophenodipyridine, benzoselenophenopyridine, selenobenzodipyridine, preferably dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1,2-azaborane, 1,3-azaborane, 1,4-azaborane, boronazole and its aza analogues. Additionally, the heteroaryl group may optionally be substituted.

[0040] Alkoxy groups—as used herein—are represented by -O-alkyl, -O-cycloalkyl, -O-heteroalkyl, or -O-heterocyclic groups. Examples and preferred examples of alkyl, cycloalkyl, heteroalkyl, and heterocyclic groups are the same as described above. An alkoxy group can 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, pentoxy, hexoxy, cyclopropyloxy, cyclobutyloxy, cyclopentoxy, cyclohexyloxy, tetrahydrofuranyloxy, tetrahydropyranyloxy, methoxypropyloxy, ethoxyethyloxy, methoxymethyloxy, and ethoxymethyloxy. Additionally, alkoxy groups may optionally be substituted.

[0041] Aryloxy group – as used herein, is represented by -O-aryl or -O-heteroaryl. Examples and preferred examples of aryl and heteroaryl groups are the same as described above. The aryloxy group can be an aryloxy group having 6 to 30 carbon atoms, preferably an aryloxy group having 6 to 20 carbon atoms. Examples of aryloxy groups include phenoxy and biphenyloxy groups. Additionally, the aryloxy group may optionally be substituted.

[0042] Arylalkyl – as used herein, encompasses aryl-substituted alkyl groups. An arylalkyl group can be an arylalkyl group having 7 to 30 carbon atoms, preferably an arylalkyl group having 7 to 20 carbon atoms, and more preferably an arylalkyl group having 7 to 13 carbon atoms. Examples of arylalkyl 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 The compounds include alkyl groups, such as o-methylbenzyl, p-chlorobenzyl, m-chlorobenzyl, o-chlorobenzyl, p-bromobenzyl, m-bromobenzyl, o-bromobenzyl, p-iodobenzyl, m-iodobenzyl, o-iodobenzyl, p-hydroxybenzyl, m-hydroxybenzyl, o-hydroxybenzyl, p-aminobenzyl, m-aminobenzyl, o-aminobenzyl, p-nitrobenzyl, m-nitrobenzyl, o-nitrobenzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-hydroxy-2-phenylisopropyl, and 1-chloro-2-phenylisopropyl. Among the above, benzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, and 2-phenylisopropyl are preferred. Additionally, the alkyl group may optionally be substituted.

[0043] Alkylsilyl – as used herein, encompasses alkyl-substituted silyl groups. The alkylsilyl group can 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, tritert-butylsilyl, triisobutylsilyl, dimethyltert-butylsilyl, and methylditert-butylsilyl. Furthermore, the alkylsilyl group may optionally be substituted.

[0044] Arylsilane – as used herein, encompasses at least one aryl-substituted silane group. The arylsilane can be an arylsilane having 6 to 30 carbon atoms, preferably an arylsilane having 8 to 20 carbon atoms. Examples of arylsilanes include triphenylsilyl, phenyldiphenylsilyl, diphenylbiphenylsilyl, phenyldiethylsilyl, diphenylethylsilyl, phenyldimethylsilyl, diphenylmethylsilyl, phenyldiisopropylsilyl, diphenylisopropylsilyl, diphenylbutylsilyl, diphenylisobutylsilyl, and diphenyltert-butylsilyl. Additionally, the arylsilane may optionally be substituted.

[0045] Alkylgermanium group – as used herein, encompasses alkyl-substituted germanium groups. The alkylgermanium group can be an alkylgermanium group having 3 to 20 carbon atoms, preferably an alkylgermanium group having 3 to 10 carbon atoms. Examples of alkylgermanium groups include trimethylgermanium, triethylgermanium, methyldiethylgermanium, ethyldimethylgermanium, tripropylgermanium, tributylgermanium, triisopropylgermanium, methyldiisopropylgermanium, dimethylisopropylgermanium, tritert-butylgermanium, triisobutylgermanium, dimethyltert-butylgermanium, and methylditert-butylgermanium. Furthermore, the alkylgermanium group may optionally be substituted.

[0046] Arylgermanium – as used herein, encompasses a germanium group substituted with at least one aryl or heteroaryl group. The arylgermanium group can be an arylgermanium group having 6 to 30 carbon atoms, preferably an arylgermanium group having 8 to 20 carbon atoms. Examples of arylgermanium groups include triphenylgermanium, phenyldiphenylgermanium, diphenylbiphenylgermanium, phenyldiethylgermanium, diphenylethylgermanium, phenyldimethylgermanium, diphenylmethylgermanium, phenyldiisopropylgermanium, diphenylisopropylgermanium, diphenylbutylgermanium, diphenylisobutylgermanium, and diphenyltert-butylgermanium. Additionally, the arylgermanium group may optionally be substituted.

[0047] The term "aza" in azadibenzofuran, azadibenzothiophene, etc., refers to the substitution of one or more CH groups in the corresponding aromatic segment 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 aforementioned aza derivatives will readily conceive of those skilled in the art, and all such analogs are identified as being included in the terminology used herein.

[0048] In this disclosure, unless otherwise defined, the term "substituted alkyl," "substituted cycloalkyl," "substituted heteroalkyl," "substituted heterocyclic," "substituted aralkyl," "substituted alkoxy," "substituted aryloxy," "substituted alkenyl," "substituted alkynyl," "substituted aryl," "substituted heteroaryl," "substituted alkylsilyl," "substituted arylsilyl," "substituted alkylgermanium," "substituted arylgermanium," "substituted amino," "substituted acyl," "substituted carbonyl," and "substituted carboxylic acid" are used interchangeably. Substituted ester group, substituted sulfinyl group, substituted sulfonyl group, substituted phosphinyl group, refers to any one of the following groups: alkyl, cycloalkyl, heteroalkyl, heterocyclic, aralkyl, alkoxy, aryloxy, alkenyl, alkynyl, aryl, heteroaryl, alkylsilyl, arylsilyl, alkylgermanium, arylgermanium, amino, acyl, carbonyl, carboxylic acid, ester group, sulfinyl, sulfonyl, and phosphinyl. One or more groups can be selected from deuterium, halogen, unsubstituted alkyl groups having 1-20 carbon atoms, and unsubstituted alkyl groups having... Cycloalkyl groups with 3-20 carbon atoms, unsubstituted heteroalkyl groups with 1-20 carbon atoms, unsubstituted heterocyclic groups with 3-20 carbon atoms, unsubstituted aralkyl groups with 7-30 carbon atoms, unsubstituted alkoxy groups with 1-20 carbon atoms, unsubstituted aryloxy groups with 6-30 carbon atoms, unsubstituted alkenyl groups with 2-20 carbon atoms, unsubstituted alkynyl groups with 2-20 carbon atoms, and unsubstituted aryl groups with 6-30 carbon atoms. Unsubstituted heteroaryl groups having 3-30 carbon atoms, unsubstituted alkylsilyl groups having 3-20 carbon atoms, unsubstituted arylsilyl groups having 6-20 carbon atoms, unsubstituted alkylgermanium groups having 3-20 carbon atoms, unsubstituted arylgermanium groups having 6-20 carbon atoms, and unsubstituted amino, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphine, and combinations thereof having 0-20 carbon atoms.

[0049] It should be understood that when a molecular segment is described as a substituent or otherwise attached to another part, its name may be written according to whether it is a segment (e.g., phenyl, phenylene, naphthyl, dibenzofuranyl) or according to whether it is a whole molecule (e.g., benzene, naphthalene, dibenzofuran). As used herein, these different ways of specifying substituents or attaching segments are considered equivalent.

[0050] In the compounds mentioned in this disclosure, hydrogen atoms can be partially or completely replaced by deuterium. Other atoms such as carbon and nitrogen can also be replaced by their other stable isotopes. Substitution with other stable isotopes in the compounds is likely preferred due to their ability to enhance device efficiency and stability.

[0051] In the compounds mentioned in this disclosure, polysubstituted means including disubstituted, up to the maximum range of available substitutions. When a substituent in a compound mentioned in this disclosure represents polysubstituted (including disubstituted, trisubstituted, tetrasubstituted, etc.), it means that the substituent can be present at multiple available substitution positions on its linkage structure. The substituent present at multiple available substitution positions can be the same structure or different structures.

[0052] In the compounds mentioned in this disclosure, unless explicitly specified, for example, that adjacent substituents can optionally connect to form a ring, adjacent substituents in the compounds cannot connect to form a ring. In the compounds mentioned in this disclosure, the optional connection of adjacent substituents to form a ring includes both cases where adjacent substituents can connect to form a ring and cases where adjacent substituents do not connect to form a ring. When adjacent substituents can optionally connect to form a ring, the formed ring can be a monocyclic or polycyclic ring (including spirocyclic, bridged, fused rings, etc.), as well as an alicyclic, heterocyclic, aromatic, or heteroaromatic ring. In this context, 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.

[0053] The statement that adjacent substituents can optionally connect to form a ring is also intended to be understood as referring to two substituents bonded to the same carbon atom connecting to each other via chemical bonds to form a ring, as exemplified by the following formula:

[0054]

[0055] The statement that adjacent substituents can optionally link to form a ring is also intended to be understood as referring to two substituents bonded to carbon atoms directly bonded to each other forming a ring through chemical bonds, as exemplified by the following formula:

[0056]

[0057] The statement that adjacent substituents can optionally connect to form a ring is also intended to be understood as referring to two substituents bonded to a further distant carbon atom connecting to each other by chemical bonds to form a ring, which can be exemplified by the following formula:

[0058]

[0059] Furthermore, the statement that adjacent substituents can optionally connect 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 bonds to the position where the hydrogen atom is bonded, thereby forming a ring. This is illustrated by the following example:

[0060]

[0061] According to one embodiment of the present invention, an organic electroluminescent device is disclosed, comprising:

[0062] anode,

[0063] cathode,

[0064] and the first organic layer and the second organic layer disposed between the anode and the cathode.

[0065] Wherein, the HOMO energy level of the first organic layer is HOMO 第一有机层 The giant surface potential is GSP 第一有机层 The HOMO energy level of the second organic layer is HOMO. 第二有机层 The giant surface potential is GSP 第二有机层 HOMO 第一有机层 -HOMO 第二有机层 ≥0.05, and GSP 第一有机层 -GSP 第二有机层 ≥30mV / nm, GSP 第一有机层 >0, GSP 第二有机层 <0.

[0066] According to one embodiment of the present invention, the first organic layer has positive GSP, and the first organic layer induces negative charge in the direction near the anode and positive charge in the direction near the cathode.

[0067] According to one embodiment of the present invention, the second organic layer has negative GSP, and the second organic layer induces positive charge in the direction near the anode and negative charge in the direction near the cathode.

[0068] According to one embodiment of the present invention, the HOMO energy levels of the first organic layer and the second organic layer satisfy HOMO 第一有机层 -HOMO 第二有机层 ≥0.1eV.

[0069] According to one embodiment of the present invention, the HOMO energy levels of the first organic layer and the second organic layer satisfy HOMO 第一有机层 -HOMO 第二有机层 ≥0.2eV.

[0070] According to one embodiment of the present invention, the thickness of the second organic layer is less than 7 nm.

[0071] According to one embodiment of the present invention, the thickness of the second organic layer is greater than 3 nm and less than or equal to 5 nm.

[0072] According to one embodiment of the present invention, the first organic layer is a first electron blocking layer, the second organic layer is a second electron blocking layer, and the second organic layer is closer to the cathode than the first organic layer.

[0073] According to one embodiment of the present invention, the organic electroluminescent device further includes an emissive layer and a hole transport layer, wherein the first organic layer and the second organic layer are disposed between the emissive layer and the hole transport layer.

[0074] According to one embodiment of the present invention, the second organic layer is disposed on the first organic layer.

[0075] According to one embodiment of the present invention, the first organic layer and the second organic layer are in direct contact.

[0076] According to one embodiment of the present invention, the second organic layer is in direct contact with the light-emitting layer.

[0077] According to one embodiment of the present invention, HOMO 第一有机层 ≥-5.20eV.

[0078] According to one embodiment of the present invention, 0≤GSP 第一有机层 ≤+10mV / nm.

[0079] According to one embodiment of the present invention, the giant surface potential of the light-emitting layer is GSP. 发光层 GSP 发光层 ≥0mV / nm.

[0080] According to one embodiment of the present invention, GSP 发光层 ≥+20mV / nm.

[0081] According to one embodiment of the present invention, the organic electroluminescent device further includes a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

[0082] According to one embodiment of the present invention, the first organic layer comprises a first compound.

[0083] According to one embodiment of the present invention, the HOMO energy level of the first compound is HOMO. 第一化合物 The first compound was selected from HOMO 第一化合物Aromatic amine compounds with a value of ≥-5.20 eV; preferably, the first compound is an aromatic amine compound containing a fluorene group.

[0084] According to one embodiment of the present invention, the first compound has a structure represented by Formula 1:

[0085]

[0086] In Equation 1,

[0087] Ar1 and Ar2 are selected from substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, or combinations thereof;

[0088] Q0 is selected from C or Si each time it appears, either the same or different.

[0089] X is selected from CR1 or N each time it appears, either the same or different.

[0090] L0, L1, and L2, when appearing in the same or different ways, are selected from single bonds, substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, or combinations thereof.

[0091] R and R1, each time appearing, are selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3-20 cyclic carbon atoms, substituted or unsubstituted heteroalkyl groups having 1-20 carbon atoms, substituted or unsubstituted heterocyclic groups having 3-20 cyclic carbon atoms, substituted or unsubstituted aralkyl groups having 7-30 carbon atoms, substituted or unsubstituted alkoxy groups having 1-20 carbon atoms, substituted or unsubstituted aroxy groups having 6-30 carbon atoms, substituted or unsubstituted alkenyl groups having 2-20 carbon atoms, substituted or unsubstituted... Alkynyl groups having 2-20 carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3-20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6-20 carbon atoms, substituted or unsubstituted alkylgermanium groups having 3-20 carbon atoms, substituted or unsubstituted arylgermanium groups having 6-20 carbon atoms, substituted or unsubstituted amino, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphinyl, and combinations thereof having 0-20 carbon atoms;

[0092] Adjacent substituents R1 can optionally connect to form a ring.

[0093] According to one embodiment of the present invention, wherein L0, L1, L2, each time they appear, are selected from single bonds, substituted or unsubstituted aryl groups having 6-20 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-20 carbon atoms, or combinations thereof.

[0094] According to one embodiment of the present invention, the L0, each time it appears, is selected from the same or different groups of substituted or unsubstituted phenylene, substituted or unsubstituted biphenylene, substituted or unsubstituted terphenylene, substituted or unsubstituted naphthylene, substituted or unsubstituted fluorene, substituted or unsubstituted silylfluorene, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzoselenophene, substituted or unsubstituted phenanthroline, substituted or unsubstituted terphenylene, substituted or unsubstituted pyridylene, substituted or unsubstituted spirodifluorene, substituted or unsubstituted anthracene, substituted or unsubstituted pyrene, or combinations thereof;

[0095] The L1 and L2, each time appearing, are selected from the same or different groups of single bonds, substituted or unsubstituted phenylene, substituted or unsubstituted biphenylene, substituted or unsubstituted terphenylene, substituted or unsubstituted naphthylene, substituted or unsubstituted fluorene, substituted or unsubstituted silylfluorene, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzoselenophene, substituted or unsubstituted phenanthylene, substituted or unsubstituted terphenylene, substituted or unsubstituted pyridylene, substituted or unsubstituted spirodifluorene, substituted or unsubstituted anthracene, substituted or unsubstituted pyrene, or combinations thereof.

[0096] According to one embodiment of the present invention, the L0 is selected from substituted or unsubstituted phenylene or substituted or unsubstituted biphenylene each time it appears.

[0097] According to one embodiment of the present invention, R is selected, in the same or different ways, from substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, or combinations thereof.

[0098] According to one embodiment of the present invention, R is selected, in the same or different ways, from substituted or unsubstituted aryl groups having 6-30 carbon atoms, or from substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms.

[0099] According to one embodiment of the invention, R is selected, in the same or different ways, from substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted dibenzofuran, or substituted or unsubstituted dibenzothiophene.

[0100] According to one embodiment of the invention, R' and R1, each time appearing, are selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3-20 cyclic carbon atoms, substituted or unsubstituted heteroalkyl groups having 1-20 carbon atoms, substituted or unsubstituted heterocyclic groups having 3-20 cyclic atoms, substituted or unsubstituted aralkyl groups having 7-30 carbon atoms, substituted or unsubstituted alkoxy groups having 1-20 carbon atoms, substituted or unsubstituted aroxy groups having 6-30 carbon atoms, substituted or unsubstituted alkenyl groups having 2-20 carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, or combinations thereof; adjacent substituents R' and R1 can optionally be linked to form a ring.

[0101] According to one embodiment of the invention, R' and R1 are selected, in the same or different ways, from hydrogen, deuterium, substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, or combinations thereof.

[0102] According to one embodiment of the present invention, Q0 is C.

[0103] According to one embodiment of the present invention, Q0 is Si.

[0104] According to one embodiment of the present invention, Ar1 and Ar2 are selected from substituted or unsubstituted aryl groups having 6-20 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-20 carbon atoms, or combinations thereof.

[0105] According to one embodiment of the invention, the Ar2, each time it appears, is selected from the same or different groups of substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted spirofluorenyl, substituted or unsubstituted silylfluorenyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted dibenzoselenophenyl, substituted or unsubstituted phenanthyl, substituted or unsubstituted triphenylene, substituted or unsubstituted pyridyl, substituted or unsubstituted carbazoleyl, substituted or unsubstituted anthraceneyl, substituted or unsubstituted pyreneyl, or combinations thereof.

[0106] According to one embodiment of the present invention, the Ar1 is selected from fluorene.

[0107] According to one embodiment of the present invention, the first compound is selected from the group consisting of compounds C1 to C24:

[0108]

[0109]

[0110] According to one embodiment of the present invention, the second organic layer comprises a second compound.

[0111] According to one embodiment of the present invention, the HOMO energy level of the second compound is HOMO. 第二化合物 The second compound is selected from HOMO 第二化合物 Heterocyclic compounds with a value of <-5.25 eV; preferably, the second compound is an N-containing heterocyclic compound comprising a carbazole or spirocyclic structure.

[0112] According to one embodiment of the present invention, the second compound comprises a structure represented by Formula 2 or Formula 3:

[0113]

[0114] In Equation 2,

[0115] X a Each time it appears, it is selected from CR in the same or different ways. a Or N;

[0116] L a Each time it appears, it is selected from substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, or combinations thereof, either identically or differently.

[0117] Ar a Each time it appears, it is selected from substituted or unsubstituted aryl groups having 6-30 carbon atoms, or substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, either in the same or different manner.

[0118] R aEach time it appears, it is selected from the group consisting of the same or different groups of the following: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3-20 cyclic carbon atoms, substituted or unsubstituted heteroalkyl groups having 1-20 carbon atoms, substituted or unsubstituted heterocyclic groups having 3-20 cyclic carbon atoms, substituted or unsubstituted aralkyl groups having 7-30 carbon atoms, substituted or unsubstituted alkoxy groups having 1-20 carbon atoms, substituted or unsubstituted aroxy groups having 6-30 carbon atoms, substituted or unsubstituted alkenyl groups having 2-20 carbon atoms, substituted or unsubstituted alkenyl groups having 2-20 carbon atoms, and substituted or unsubstituted alkyl groups having 1-20 carbon atoms. Alkynyl groups having 2-20 carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3-20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6-20 carbon atoms, substituted or unsubstituted alkylgermanium groups having 3-20 carbon atoms, substituted or unsubstituted arylgermanium groups having 6-20 carbon atoms, substituted or unsubstituted amino, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphinyl, and combinations thereof having 0-20 carbon atoms;

[0119] In Formula 2, adjacent substituents can optionally connect to form a ring;

[0120] In Equation 3, W is selected from single bonds, and CR b 'R b ', SiR b 'R b ', O or S;

[0121] L b Selected from single bonds, substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, or combinations thereof;

[0122] Ar b Each time it appears, it is selected from aryl groups having 6-30 carbon atoms, heteroaryl groups having 3-30 carbon atoms, or combinations thereof, either identically or differently.

[0123] R b Each occurrence, whether identical or different, indicates monosubstitution, polysubstitution, or no substitution;

[0124] R b R bEach time it appears, it is selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3-20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1-20 carbon atoms, substituted or unsubstituted heterocyclic groups having 3-20 ring atoms, substituted or unsubstituted aralkyl groups having 7-30 carbon atoms, substituted or unsubstituted alkoxy groups having 1-20 carbon atoms, substituted or unsubstituted aroxy groups having 6-30 carbon atoms, substituted or unsubstituted groups having 2-20 carbon atoms. Alkenyl, substituted or unsubstituted alkynyl groups having 2-20 carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3-20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6-20 carbon atoms, substituted or unsubstituted alkylgermanium groups having 3-20 carbon atoms, substituted or unsubstituted arylgermanium groups having 6-20 carbon atoms, acyl, carbonyl, carboxylic acid, ester, cyano, isocyano, hydroxyl, mercapto, sulfinyl, sulfonyl, phosphin, and combinations thereof.

[0125] According to an embodiment of the present invention, in formula 2, L a It is selected from substituted or unsubstituted phenylene, substituted or unsubstituted biphenylene, substituted or unsubstituted terphenylene, substituted or unsubstituted naphthylene, substituted or unsubstituted fluorene, substituted or unsubstituted silylfluorene, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted dibenzoselenophenyl, substituted or unsubstituted phenanthyl, substituted or unsubstituted terphenylene, substituted or unsubstituted pyridyl, substituted or unsubstituted spirodifluorene, substituted or unsubstituted anthracene, substituted or unsubstituted pyrene, or combinations thereof.

[0126] According to one embodiment of the present invention, L a Selected from substituted or unsubstituted phenylene, or substituted or unsubstituted biphenylene.

[0127] According to one embodiment of the present invention, L a It is a phenylene or biphenylene.

[0128] According to an embodiment of the present invention, in formula 2, R a Selected from hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3-20 cyclic carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, and substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms; preferably, R aSelected from hydrogen, deuterium, substituted or unsubstituted aryl groups having 6-30 carbon atoms, and substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms.

[0129] According to an embodiment of the present invention, in formula 2, Ar a Selected from substituted or unsubstituted aryl groups having 6-20 carbon atoms, and substituted or unsubstituted heteroaryl groups having 3-20 carbon atoms; preferably, Ar a It is selected from phenyl, biphenyl, terphenyl, naphthyl, fluorenyl, dibenzothiophene, spirodifluorenyl, pyridyl or pyrimidinyl.

[0130] According to one embodiment of the present invention, in formula 3, W is selected from single bonds, CR b 'R b ', O; preferably, W is selected from single bonds, CR b 'R b More preferably, W is selected from single bonds.

[0131] According to an embodiment of the present invention, in formula 3, L b Selected from substituted or unsubstituted phenylene, substituted or unsubstituted biphenylene, substituted or unsubstituted terphenylene, substituted or unsubstituted naphthylene, substituted or unsubstituted fluorene, substituted or unsubstituted silylfluorene, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzoselenophene, substituted or unsubstituted phenanthylene, substituted or unsubstituted terphenylene, substituted or unsubstituted pyridylene, substituted or unsubstituted spirodifluorene, substituted or unsubstituted anthracene, substituted or unsubstituted pyrene, or combinations thereof; preferably, L b Selected from substituted or unsubstituted phenylene, or substituted or unsubstituted biphenylene; more preferably, L b It is a phenylene or biphenylene.

[0132] According to an embodiment of the present invention, in formula 3, R b Selected from hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3-20 cyclic carbon atoms, substituted or unsubstituted aryl groups having 6-30 carbon atoms, and substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms; preferably, R b Selected from hydrogen, deuterium, substituted or unsubstituted aryl groups having 6-30 carbon atoms, and substituted or unsubstituted heteroaryl groups having 3-30 carbon atoms. According to one embodiment of the invention, in Formula 3, Ar... b Selected from substituted or unsubstituted aryl groups having 6-20 carbon atoms, and substituted or unsubstituted heteroaryl groups having 3-20 carbon atoms; preferably, Ar bIt is selected from phenyl, biphenyl, terphenyl, naphthyl, fluorenyl, dibenzothiophene, spirodifluorenyl, pyridyl or pyrimidinyl.

[0133] According to one embodiment of the present invention, the second compound is selected from the group consisting of:

[0134]

[0135]

[0136] According to one embodiment of the present invention, the peak wavelength of the electroluminescence spectrum of the light-emitting layer is between 600 nm and 700 nm.

[0137] According to one embodiment of the present invention, the peak wavelength of the electroluminescence spectrum of the light-emitting layer is between 620 nm and 630 nm.

[0138] According to one embodiment of the present invention, the peak wavelength of the electroluminescence spectrum of the light-emitting layer is between 500 nm and 600 nm.

[0139] According to one embodiment of the present invention, the peak wavelength of the electroluminescence spectrum of the light-emitting layer is between 520 nm and 540 nm.

[0140] According to one embodiment of the present invention, the peak wavelength of the electroluminescence spectrum of the light-emitting layer is between 400 nm and 500 nm.

[0141] According to one embodiment of the present invention, the peak wavelength of the electroluminescence spectrum of the light-emitting layer is between 450 nm and 460 nm.

[0142] According to one embodiment of the present invention, an electronic device is disclosed, which includes the organic electroluminescent device described in any of the foregoing embodiments.

[0143] Combination with other materials

[0144] The materials described in this invention for specific layers in organic light-emitting devices can be used in combination with a variety of other materials present in the device. These combinations of materials are described in detail in paragraphs 0132-0161 of U.S. Patent Application US2016 / 0359122A1, the entire contents of which are incorporated herein by reference. The materials described or mentioned herein 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.

[0145] Materials described herein for use in specific layers of organic light-emitting devices can be used in combination with a variety of other materials present in said devices. For example, the compounds disclosed herein can be used in combination with a variety of light-emitting dopants, substrates, transport layers, blocking layers, implantation layers, electrodes, and other possible layers. These combinations of materials are 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 herein 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.

[0146] In the embodiments of the device, the characteristics of the device are tested using equipment conventional in the art (including but not limited to vapor deposition machines manufactured by Angstrom Engineering, optical testing systems and lifetime testing systems manufactured by Suzhou Fushida, ellipsometers manufactured by Beijing Liangtuo, etc.) and methods well known to those skilled in the art. Since those skilled in the art are familiar with the use of the above-mentioned equipment, testing methods, and other related content, and can obtain the inherent data of the sample reliably and unaffected, the above-mentioned related content will not be elaborated in this patent.

[0147] In this paper, the HOMO energy level (highest occupied orbital) values ​​were obtained using electrochemical cyclic voltammetry, the most commonly used method for determining the energy levels of organic materials. The tests were conducted using a CorrTest CS120 electrochemical workstation manufactured by Wuhan CorrTest Instruments Co., Ltd., employing a three-electrode system: a platinum disk electrode as the working electrode, an Ag / AgNO3 electrode as the reference electrode, and a platinum wire electrode as the auxiliary electrode. Anhydrous DCM was used as the solvent, and 0.1 mol / L tetrabutylammonium hexafluorophosphate was used as the supporting electrolyte. The test compound was prepared by adding 10... -3 A mol / L solution was used, and nitrogen gas was bubbled into the solution for 10 min to remove oxygen before testing. Instrument parameters were set as follows: scan rate 100 mV / s, potential interval 0.5 mV, and test window -1 V to 1 V. The HOMO levels of some compounds used in the device examples of this invention were measured using the aforementioned method, and the results are listed in Table 1 below.

[0148] In this paper, all "HOMO levels" are represented by negative values; the smaller the value (i.e., the larger the absolute value), the deeper the energy level. The statement that an energy level is less than a certain number in this application means that the energy level is numerically smaller than that number, i.e., has a more negative value.

[0149] Taking the testing of the first organic layer GSP as an example, the specific steps of the giant surface potential (GSP) testing method used in this invention are as follows:

[0150] GSP device 1: First, prepare as follows Figure 1 Device 100 uses a 0.7 mm thick glass substrate on which a pre-patterned ITO anode 101 is formed. After cleaning the substrate with deionized water and detergent, the anode surface was treated with oxygen plasma and UV ozone. Subsequently, the substrate was dried in a glove box to remove moisture and then placed on a support and transferred to the vacuum chamber. The organic layers specified below are used at a vacuum degree of approximately 10... -6 In the case of Torr, The deposition rate is achieved by sequentially depositing compounds HI-2 and HI-3 onto the anode via vacuum thermal evaporation. These compounds form a hole injection layer 110 (HIL). HI-2:HI-3 = 3:97). Subsequently, compound HI-3 was vapor-deposited as hole transport layer 120 (HTL). Next, compound C11 was vapor-deposited as the test material layer 130. Finally, silver (Ag) is vapor-deposited onto the test material layer 130 as a cathode 140. Finally, glass encapsulation 102 is performed to ensure structural stability and isolate environmental interference during testing.

[0151] The device uses more than one layer of material, which is obtained by doping different compounds in their recorded weight ratios.

[0152] GSP Device 2: The fabrication method is the same as GSP Device 1, except that the thickness of the material layer to be tested is...

[0153] GSP Device 3: The fabrication method is the same as GSP Device 1, except that the thickness of the test material layer is...

[0154] GSP Device 4: The fabrication method is the same as GSP Device 1, except that the thickness of the test material layer is...

[0155] GSP Device 5: The fabrication method is the same as GSP Device 1, except that the thickness of the test material layer is...

[0156] GSP Device 6: The fabrication method is the same as GSP Device 1, except that the thickness of the test material layer is...

[0157] Subsequently, capacitance-voltage (CV) measurements were performed on GSP devices 1–6 of different thicknesses. Using an impedance analyzer at a frequency of 500 Hz and an AC signal amplitude of 100 mV, capacitance was measured from -6.0 V to +8.0 V in 0.1 V steps to obtain stable capacitance-voltage curves. Then, the hole injection voltage V was determined from each capacitance-voltage curve. inj This typically corresponds to the turning point where capacitance begins to rise significantly. The V values ​​corresponding to different thicknesses... inj By performing a linear fit, we obtain Formula 1:

[0158] V inj =k·d+b (Formula 1)

[0159] The slope k (mV / nm) reflects the rate of change of hole injection voltage with thickness, d is the thickness (nm) of the material layer under test, which is used as the independent variable in the fitting to represent the effect of thickness change on hole injection voltage. b is the intercept of the fitted line, which reflects the contribution of factors other than thickness to GSP.

[0160] According to physical principles, the giant surface potential GSP inside the functional layer has a relationship with this slope as expressed in Equation 2:

[0161] GSP = -k (Formula 2)

[0162] Table 1 shows the measured data of the highest occupied molecular orbital (HOMO) and giant surface potential (GSP) of the aforementioned test materials. The specific compounds used in the test materials are shown in Table 1, and the structures of the specific compounds are described in the following examples.

[0163] Table 1. HOMO levels and GSP values ​​of the first and second organic layers.

[0164]

[0165] Table 1 lists the HOMO levels (HOMO) of the first organic layer with different combinations of second organic layer materials in specific embodiments of the present invention. 第一有机层 HOMO 第二有机层 ) and giant surface potential (GSP) 第一有机层 GSP 第二有机层 The measured data were used to calculate the corresponding HOMO level difference (ΔHOMO = HOMO). 第一有机层 –HOMO 第二有机层 ) and GSP difference (ΔGSP=GSP) 第一有机层 –GSP 第二有机层 This provides specific material data support for the "HOMO and GSP collaborative matching" proposed in this invention.

[0166] The present invention will be described in more detail below with reference to the following embodiments. The compounds used in the following embodiments are readily available to those skilled in the art, and their synthesis methods are not described in detail here. Obviously, the following embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Those skilled in the art can reasonably improve the preparation methods of the following embodiments based on existing technology. For example, the proportions of various materials in the light-emitting layer are not particularly limited, and those skilled in the art can reasonably select them within a certain range based on existing technology. For instance, based on the total weight of the light-emitting layer materials, the main material can account for 70%-99%, and the light-emitting material can account for 1%-30%. In the device embodiments, the device characteristics are also tested using conventional equipment in the art (including but not limited to evaporation machines manufactured by Angstrom Engineering, optical testing systems manufactured by Suzhou Fushida, ellipsometers manufactured by Beijing Liangtuo, etc.) using methods well known to those skilled in the art.

[0167] Example 1:

[0168] Preparation such as Figure 2 The device 200 shown uses a 0.7mm thick glass substrate with a pre-patterned design. The ITO anode 201 was prepared by washing the substrate with deionized water and detergent, followed by treatment of the anode surface with oxygen plasma and UV ozone. Subsequently, the substrate was dried in a glove box to remove moisture and then placed on a support and transferred into a vacuum chamber. The organic layer specified below was prepared under a vacuum of approximately 10... -6 In the case of torr, The deposition rate is achieved sequentially on the anode layer 201 via vacuum thermal evaporation. First, compound HT-1 and compound HI-1 are simultaneously deposited to form a hole injection layer 210 (HIL). Next, compound HT-1 was vapor-deposited as hole transport layer 220 (HTL). Subsequently, compound C11 was deposited sequentially as the first organic layer 230 (EBL1); Compound P-1 is deposited on it as a second organic layer 240 (EBL2), Compounds RH-1 and RD-1 are simultaneously deposited on it as the luminescent layer 250 (EML, 97:3). Next, compound H-2 was sequentially deposited as a hole-blocking layer 260 (HBL). On top of this, compounds ET and Liq are simultaneously deposited as an electron transport layer 270 (ETL, ET:Liq = 40:60). Liq is deposited on top as an electron injection layer with a thickness of 280 nm. Finally, aluminum is vapor-deposited as the cathode 290 (Cathode). Finally, glass encapsulation 202 is performed.

[0169] The device uses more than one layer of material, which is obtained by doping different compounds in their recorded weight ratios.

[0170] Example 2: The preparation method is the same as in Example 1, except that H-22 is used for the second organic layer.

[0171] Example 3: The preparation method is the same as in Example 1, except that P-26 is used for the second organic layer.

[0172] Comparative Example 1: The preparation method is the same as in Example 1, except that C11 is used for the second organic layer.

[0173] Comparative Example 2: The preparation method is the same as in Example 1, except that the second organic layer uses D-1.

[0174] Comparative Example 3: The preparation method is the same as in Example 1, except that D-2 is used for the second organic layer.

[0175] Comparative Example 4: The preparation method is the same as in Example 1, except that D-3 is used for the second organic layer.

[0176] Table 2. Partial device structures of Examples 1-3 and Comparative Examples 1-4

[0177] Number First organic layer Second organic layer Example 1 C11 P-1 Example 2 C11 H-22 Example 3 C11 P-26 Comparative Example 1 C11 C11 Comparative Example 2 C11 D-1 Comparative Example 3 C11 D-2 Comparative Example 4 C11 D-3

[0178] The structure of the compound used in the device is shown below:

[0179]

[0180] Table 3 summarizes the device performance of Examples 1 to 3 and Comparative Examples 1 to 4. The external quantum efficiency (EQE) is calculated at a current density of 10 mA / cm². 2 The maximum capacitance (Cmax) was measured using an impedance analyzer (Keysight E4990A): a DC bias voltage of -4V to 5V was applied to the two electrodes of the device, while a 100mV sinusoidal AC voltage signal was simultaneously superimposed, and tests were performed at an AC voltage frequency of 500Hz. The CV curve of the device was measured, and the maximum capacitance Cmax of the device was obtained. These data are recorded and shown in Table 3.

[0181] Table 3. Partial device performance of Examples 1-3 and Comparative Examples 1-4

[0182]

[0183] discuss:

[0184] Referring to Tables 1-3, Comparative Example 1 used the same compound C11 as the first and second organic layers; Comparative Example 2 used compounds C11 and D-1 as the first and second organic layers, respectively. GSP 第一有机层 –GSP 第二有机层 =36.5mV / nm, HOMO 第一有机层 –HOMO 第二有机层 = -0.15eV; the organic electroluminescent device has a typical external quantum efficiency of 24.9% and 25.8%, and a relatively large maximum capacitance of 3.10nF and 2.81nF. In contrast, Examples 1-3 introduce GSP-compliant... 第一有机层 –GSP 第二有机层 ≥30mV / nm and HOMO 第一有机层 –HOMO 第二有机层 Compounds P-1, H-22, and P-26, with a second organic layer voltage of ≥0.05 eV, significantly reduced device capacitance by 46%-48% while maintaining high external quantum efficiencies of 26.6%, 25.6%, and 26.4%, respectively. This performance improvement stems from the synergistic regulation mechanism of GSP and HOMO energy levels. Specific GSP relationships enable the first and second organic layers to form built-in electric fields of opposite directions and specific strengths. These built-in electric fields can regulate the interface charge distribution and suppress charge accumulation. Simultaneously, the energy levels determine the energy barrier for carrier injection, and the necessary HOMO energy level difference ensures effective carrier transport, thereby reducing carrier accumulation while maintaining efficiency and further optimizing capacitance.

[0185] Comparative Examples 3 and 4 used compounds D-2 and D-3 as the second organic layer. Although compounds D-2 and D-3 have negative gas point differences (GSPs), their GSP differences with the first organic layer are 7.1 mV / nm and 1.4 mV / nm, respectively, far below 30 mV / nm. The capacitance reduction is limited, indicating that relying solely on a negative GSP sign without sufficient difference is insufficient to form an effective built-in electric field to regulate interface charge. Notably, although Comparative Example 2 meets the GSP difference requirement, its HOMO energy level difference is only 0.015 eV, yet the capacitance is still as high as 2.81 nF, significantly different from the examples. This demonstrates that even with a sufficient GSP difference, if carrier energy level matching is insufficient, a large barrier will still hinder effective carrier transport, causing interface charge accumulation and resulting in a large capacitance.

[0186] In summary, the core of this invention lies in the dual synergistic design of GSP and HOMO energy levels: by using the GSP difference between two organic layers with different signs, a built-in electric field is established to regulate interface charge and reduce capacitance; the HOMO energy level difference ensures carrier injection through energy level matching, further reducing carrier accumulation. Both work together, and neither can be dispensed with, to ensure effective carrier transport and recombination, achieving low-capacitance devices. This provides key technical support for low power consumption, low latency, and high response speed in display panels under high refresh rates, high resolutions, and dynamic scenes, and is particularly helpful in promoting the further development of high-performance display applications such as virtual reality (VR), smartphones, and automotive displays.

[0187] It should be understood that the various embodiments described herein are merely examples and are not intended to limit the scope of the 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 substituted with other materials and structures without departing from the spirit of the invention. It should be understood that various theories regarding why the invention works are not intended to be limiting.

Claims

1. An organic electroluminescent device comprising: an anode, a cathode, and a first organic layer and a second organic layer disposed between the anode and the cathode; Wherein, the HOMO energy level of the first organic layer is HOMO 第一有机层 The giant surface potential is GSP 第一有机层 The HOMO energy level of the second organic layer is HOMO. 第二有机层 The giant surface potential is GSP 第二有机层 HOMO 第一有机层 -HOMO second organic layer ≥0.05, and GSP first organic layer - GSP second organic layer ≥30mV / nm, GSP first organic layer >0, GSP second organic layer <0.

2. The organic electroluminescent device according to claim 1, further comprising a hole transport layer and an emission layer, the first organic layer and the second organic layer being between the emission layer and the hole transport layer.

3. The organic electroluminescent device according to claim 1, wherein the second organic layer is disposed on the first organic layer; preferably, the first organic layer and the second organic layer are in direct contact.

4. The organic electroluminescent device according to claim 1, wherein the second organic layer is in direct contact with the emission layer.

5. The organic electroluminescent device according to claim 1, wherein the HOMO energy levels of the first organic layer and the second organic layer satisfy HOMO 第一有机层 - HOMO 第二有机层 ≥ 0.1 eV; preferably, HOMO 第一有机层 - HOMO 第二有机层 ≥ 0.2 eV.

6. The organic electroluminescent device according to claim 1, wherein the second organic layer has a thickness of less than 7 nm; preferably, the second organic layer has a thickness of more than 3 nm and less than or equal to 5 nm.

7. The organic electroluminescent device according to claim 1, wherein the first organic layer is a first electron blocking layer and the second organic layer is a second electron blocking layer, the second organic layer being closer to the cathode than the first organic layer.

8. The organic electroluminescent device according to claim 4, HOMO 第一有机层 ≥ -5.20 eV.

9. The organic electroluminescent device according to claim 2, 0 < GSP < +10 mV / nm. 第一有机层 ≤ +10 mV / nm.

10. The organic electroluminescent device according to claim 7, wherein the giant surface potential of the light-emitting layer is GSP 发光层 , GSP 发光 layer > 0 mV / nm; preferably GSP light-emitting layer > +20 mV / nm.

11. An electronic device comprising the organic electroluminescent device according to any one of claims 1 to 10.

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