Organic electroluminescent device and display device

Abstract

The invention provides an organic electroluminescent device and a display device. The organic light-emitting device comprises an anode (10), a cathode (90), a first hole transport layer (20) and a first light-emitting layer (40), the first hole transport layer (20) and the first light-emitting layer (40) are arranged between the anode (10) and the cathode (90), and the first hole transport layer (20) is located between the first light-emitting layer (40) and the anode (10); the first hole transport layer (20) at least comprises a first hole sub-layer (21) and a second hole sub-layer (22); materials of the first hole sub-layer (21) comprise a first material and a second material, and materials of the second hole sub-layer (22) comprise at least one of the first material and the second material. The display crosstalk phenomenon of the device is improved while the performance of the device is improved by optimizing the materials of the hole transport layer and the electron blocking layer of the OLED device and optimizing the physical property parameter relation of different functional layers of the device.

Description

Organic electroluminescent device and display device Technical Field

[0001] The present disclosure relates to, but is not limited to, the field of display technology, and in particular to a stacked organic electroluminescent device and a display apparatus. Background Art

[0002] Organic Light Emitting Device (OLED) is an active light-emitting device with advantages such as luminescence, ultra-thinness, wide viewing angle, high brightness, high contrast, low power consumption, and extremely high response speed. It has gradually become a next-generation display technology with great development prospects.

[0003] OLEDs consist of an anode, a cathode, and a light-emitting layer disposed between the anode and cathode. Their light-emitting principle is that holes and electrons are injected into the light-emitting layer from the anode and cathode, respectively. When electrons and holes meet in the light-emitting layer, they recombine to produce excitons, which emit light as they transition from an excited state to a ground state. To ensure smooth injection of electrons and holes from the electrodes into the light-emitting layer at a relatively low driving voltage, a hole injection layer and a hole transport layer are disposed between the anode and the light-emitting layer, and an electron injection layer and an electron transport layer are disposed between the cathode and the light-emitting layer. The design of the hole injection layer is crucial for OLEDs to achieve better luminous efficiency, low voltage, and a long lifespan.

[0004] Summary of the Invention

[0005] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0006] An organic electroluminescent device and a display apparatus.

[0007] An embodiment of the present disclosure provides an organic electroluminescent device, comprising an anode, a cathode, and a first hole transport layer and a first light-emitting layer disposed between the anode and the cathode, wherein the first hole transport layer is located between the first light-emitting layer and the anode; the first hole transport layer comprises at least a first hole sublayer and a second hole sublayer; a material of the first hole sublayer comprises a first material and a second material, and a material of the second hole sublayer comprises at least one of the first material and the second material; and

[0008]

[0009] In formula 1:

[0010] X is O, S, C or N

[0011] L1 and L2 are each independently a direct bond, and each independently a substituted or unsubstituted C6-C60 aryl group;

[0012] Ar1 and Ar2 are each independently hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, an ester group, an imide group, an amino group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted alkylthio group, a substituted or unsubstituted arylthio group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted unsubstituted alkenyl, substituted or unsubstituted aralkyl, substituted or unsubstituted aralkenyl, substituted or unsubstituted alkylaryl, substituted or unsubstituted alkylamino, substituted or unsubstituted aralkylamino, substituted or unsubstituted heteroarylamino, substituted or unsubstituted arylamino, substituted or unsubstituted arylheteroarylamino, substituted or unsubstituted arylphosphino, substituted or unsubstituted phosphine oxide, substituted or unsubstituted aryl, or substituted or unsubstituted heterocyclic group; or represented by the following Formula 2:

[0013]

[0014] R1, R2, R3, and R4 are each independently selected from deuterium, a halogen group, a cyano group, a C3-C20 heteroaryl group, a C6-C20 aryl group, a C3-C12 trialkylsilyl group, a C18-C30 triarylsilyl group, a C1-C5 alkyl group, a C1-C10 haloalkyl group, a C3-C10 cycloalkyl group, a C2-C10 heterocycloalkyl group, a C5-C10 cycloalkenyl group, a C4-C10 heterocycloalkenyl group, a C1-C10 alkoxy group, a C1-C10 alkylthio group, a C6-C18 aryloxy group, a C6-C18 arylthio group, a C6-C24 phosphino group, a C6-C18 alkylsulfonyl group, a C3-C18 trialkylphosphino group, and a C3-C18 trialkylboryl group; or are optionally bonded to an adjacent group to form a ring;

[0015] a, b, m, and n are each independently an integer of 0-4.

[0016] In an exemplary embodiment of the present disclosure, the first hole sublayer is located between the second hole sublayer and the anode.

[0017] In an exemplary embodiment of the present disclosure, a difference between the LUMO energy level of the first material and the HOMO energy level of the second material is between -0.3 eV and 1.0 eV.

[0018] In an exemplary embodiment of the present disclosure, the organic electroluminescent device further comprises a first electron blocking layer, wherein the first electron blocking layer is located between the first light-emitting layer and the first hole transport layer, and the difference between the HOMO energy level of the second hole sublayer material and the LUMO energy level of the first electron blocking layer is less than or equal to 0.4 eV.

[0019] In an exemplary embodiment of the present disclosure, the mobility of the second hole sublayer material is greater than the mobility of the first electron blocking layer.

[0020] In an exemplary embodiment of the present disclosure, a difference between a LUMO energy level of the first electron blocking layer and a HOMO energy level of the first light emitting layer is less than or equal to 0.4 eV.

[0021] In an exemplary embodiment of the present disclosure, the first electron blocking layer includes a first blocking sublayer, or the first electron blocking layer includes a first blocking sublayer and a second blocking sublayer, the second blocking sublayer is located between the first blocking sublayer and the first light-emitting layer, and the material of the first blocking sublayer is different from the material of the second blocking sublayer.

[0022] In an exemplary embodiment of the present disclosure, the organic electroluminescent device further includes a hole injection layer, wherein the hole injection layer is located between the first hole transport layer and the anode, and the resistivity of the hole injection layer is greater than or equal to 100 Ω·m.

[0023] In an exemplary embodiment of the present disclosure, the organic electroluminescent device further includes a charge generation layer, a second hole transport layer and a second light-emitting layer, the charge generation layer is located on the side of the first light-emitting layer close to the cathode, the second hole transport layer is located on the side of the charge generation layer close to the cathode, and the second light-emitting layer is located between the second hole transport layer and the cathode; the second hole transport layer includes at least a third hole sublayer, and the material of the third hole sublayer includes a first material and a second material.

[0024] In an exemplary embodiment of the present disclosure, the third hole sublayer is located between the second light-emitting layer and the charge generation layer.

[0025] In an exemplary embodiment of the present disclosure, the mobility M2 of the second hole sub-layer material and the mobility M4 of the third hole sub-layer material satisfy the following conditions:

[0026] 10 -1 cm 2 / Vs≤M2 / M4≤10cm 2 / Vs.

[0027] In an exemplary embodiment of the present disclosure, the organic electroluminescent device further comprises a second electron blocking layer, the second electron blocking layer comprises a third blocking sublayer, or the second electron blocking layer comprises a third blocking sublayer and a fourth blocking sublayer, the second electron blocking layer is located between the second light-emitting layer and the second hole transport layer, and the difference between the HOMO energy level of the third hole sublayer material and the LUMO energy level of the second electron blocking layer is less than or equal to 0.4 eV.

[0028] In an exemplary embodiment of the present disclosure, the mobility of the third hole sublayer material is greater than the mobility of the second electron blocking layer.

[0029] In an exemplary embodiment of the present disclosure, a difference between a LUMO energy level of the fourth blocking sublayer and a HOMO energy level of the second light emitting layer is less than or equal to 0.4 eV.

[0030] In an exemplary embodiment of the present disclosure, the second electron blocking layer includes a third blocking sublayer, or the second electron blocking layer includes a third blocking sublayer and a fourth blocking sublayer, the fourth blocking sublayer is located between the third blocking sublayer and the second light-emitting layer, and the material of the third blocking sublayer is different from the material of the fourth blocking sublayer.

[0031] In an exemplary embodiment of the present disclosure, the compound of Formula 1 is selected from one or more of the following compounds:

[0032]

[0033] In an exemplary embodiment of the present disclosure, the second material includes but is not limited to a compound having a structure of Formula 3:

[0034]

[0035] In formula 3:

[0036] A1-A6 are each independently substituted or unsubstituted halogen, substituted or unsubstituted cyano, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, and aryl substituted by an electron-deficient group or heteroaryl substituted by an electron-deficient group;

[0037] A is a 3-membered ring, a 4-membered ring, a 5-membered ring or a 6-membered ring.

[0038] In an exemplary embodiment of the present disclosure, the compound of Formula 3 is selected from one or more of the following compounds:

[0039]

[0040] In an exemplary embodiment of the present disclosure, the electron blocking layer includes, but is not limited to, a compound having a structure of Formula 4:

[0041]

[0042] In Formula 4, Ar3, Ar4, Ar5, and Ar6 are each independently a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group;

[0043] L1, L2, L3, and L4 are each independently a direct bond, and each independently a substituted or unsubstituted C6-C60 aryl group;

[0044] R5 and R6 are each independently selected from deuterium, a halogen group, a cyano group, a C3-C20 heteroaryl group, a C6-C20 aryl group, a C3-C12 trialkylsilyl group, a C18-C30 triarylsilyl group, a C1-C5 alkyl group, a C1-C10 haloalkyl group, a C3-C10 cycloalkyl group, a C2-C10 heterocycloalkyl group, a C5-C10 cycloalkenyl group, a C4-C10 heterocycloalkenyl group, a C1-C10 alkoxy group, a C1-C10 alkylthio group, a C6-C18 aryloxy group, a C6-C18 arylthio group, a C6-C24 phosphino group, a C6-C18 alkylsulfonyl group, a C3-C18 trialkylphosphino group, a C3-C18 trialkylboryl group; or optionally bonded to an adjacent group to form a ring;

[0045] Ar3, Ar4, Ar5, Ar6 are each independently the following groups:

[0046]

[0047] An embodiment of the present disclosure provides a display device including the organic electroluminescent device.

[0048] Still other aspects will become apparent upon reading and understanding the accompanying drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings are intended to provide a further understanding of the technical solutions of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solutions of the present disclosure and do not constitute a limitation of the technical solutions of the present disclosure. The shapes and sizes of the components in the drawings do not reflect the actual scale and are intended only to illustrate the contents of the present disclosure.

[0050] FIG1 is a schematic structural diagram of an OLED display device;

[0051] FIG2 is a schematic diagram of a planar structure of a display area of ​​a display substrate;

[0052] FIG3 is a schematic diagram of a cross-sectional structure of a display substrate;

[0053] FIG4 is a schematic diagram of the structure of an organic electroluminescent device according to an embodiment of the present disclosure;

[0054] FIG5 is a schematic diagram of another exemplary structure of an organic electroluminescent device according to an embodiment of the present disclosure;

[0055] 6A and 6B are schematic structural diagrams of other exemplary organic electroluminescent devices according to an embodiment of the present disclosure;

[0056] FIG7 is a schematic diagram of another exemplary organic electroluminescent device structure according to an embodiment of the present disclosure;

[0057] 8A and 8B are schematic structural diagrams of other exemplary organic electroluminescent devices according to an embodiment of the present disclosure;

[0058] FIG9 is a schematic diagram of another exemplary organic electroluminescent device structure according to an embodiment of the present disclosure;

[0059] FIG10 is a schematic structural diagram of another exemplary organic electroluminescent device according to an embodiment of the present disclosure;

[0060] FIG11 is a schematic diagram of another exemplary organic electroluminescent device structure according to an embodiment of the present disclosure;

[0061] FIG12 is an exemplary crosstalk phenomenon;

[0062] FIG. 13 is an exemplary crosstalk-free spectrum of a device of the present disclosure.

[0063] Description of reference numerals:

[0064] 10—anode; 20—first hole transport layer; 21—first hole sublayer;

[0065] 22—second hole sublayer; 20′—second hole transport layer; 21′—third hole sublayer;

[0066] 30—first electron blocking layer; 31—first blocking sublayer; 32—second blocking sublayer;

[0067] 30'—second electron blocking layer; 31'—third blocking sublayer; 32'—fourth blocking sublayer;

[0068] 40—first light-emitting layer; 40'—second light-emitting layer; 41—light-emitting layer 1;

[0069] 42—luminescent layer 2; 43—luminescent layer 3; 41′—luminescent layer 1;

[0070] 42'—luminescent layer 2; 43'—luminescent layer 3; 50—hole blocking layer;

[0071] 60—charge generation layer; 61—N-type charge generation layer; 62—P-type charge generation layer;

[0072] 80—electron transport layer; 89—electron injection layer; 90—cathode;

[0073] 101—substrate; 102—driving circuit layer; 103—light-emitting device;

[0074] 104—encapsulation layer; 201—first insulating layer; 202—second insulating layer;

[0075] 203—third insulating layer; 204—fourth insulating layer; 205—flat layer;

[0076] 210—driving transistor; 211—storage capacitor; 301—anode;

[0077] 302—pixel definition layer; 303—organic light emitting layer; 304—cathode;

[0078] 401—first encapsulation layer; 402—second encapsulation layer; 403—third encapsulation layer. DETAILED DESCRIPTION

[0079] The embodiments herein can be implemented in a variety of different forms. A person skilled in the art can easily understand that the implementation and content can be transformed into various forms without departing from the purpose and scope of the present disclosure. Therefore, the present disclosure should not be interpreted as being limited to the contents described in the following embodiments. In the absence of conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other in any manner.

[0080] In the drawings, the sizes of components, layer thicknesses, or regions may be exaggerated for clarity. Therefore, any implementation of the present disclosure is not necessarily limited to the dimensions shown in the drawings, and the shapes and sizes of components in the drawings do not reflect true proportions. Furthermore, the drawings schematically illustrate idealized examples, and any implementation of the present disclosure is not limited to the shapes or values ​​shown in the drawings.

[0081] The ordinal numbers such as "first", "second", and "third" in this article are set to avoid confusion of constituent elements, rather than to limit the quantity.

[0082] In this document, for convenience, words and phrases indicating orientation or positional relationships, such as "middle," "upper," "lower," "front," "back," "vertical," "horizontal," "top," "bottom," "inside," and "outside," are used to illustrate the positional relationships of constituent elements with reference to the accompanying drawings. This is merely to facilitate the description of the embodiments and simplify the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it should not be understood as a limitation of the present disclosure. The positional relationships of the constituent elements may be appropriately changed according to the orientation of the constituent elements being described. Therefore, the present invention is not limited to the words and phrases described herein and may be appropriately replaced according to the circumstances.

[0083] In this document, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed, removable, or integral connections; mechanical or electrical connections; direct connections, indirect connections through intermediaries, or internal communication between two components. Those skilled in the art will understand the meaning of these terms in this disclosure based on the specific circumstances.

[0084] In this article, a transistor refers to a device that includes at least three terminals: a gate electrode, a drain electrode, and a source electrode. A transistor has a channel region between a drain electrode (or drain electrode terminal, drain region, or drain electrode) and a source electrode (or source electrode terminal, source region, or source electrode), and current can flow through the drain electrode, the channel region, and the source electrode. In this article, the channel region refers to the region through which current primarily flows.

[0085] In this article, the first electrode can be a drain electrode and the second electrode can be a source electrode, or vice versa. When using transistors with opposite polarity or when the direction of current changes during circuit operation, the functions of "source electrode" and "drain electrode" can sometimes be reversed. Therefore, in this article, "source electrode" and "drain electrode" can be reversed.

[0086] As used herein, "electrically connected" includes components connected together via an element having some electrical function. This "element having some electrical function" is not particularly limited as long as it enables the transfer of electrical signals between the connected components. Examples of this "element having some electrical function" include electrodes or wiring, switching elements such as transistors, and other functional components such as resistors, inductors, and capacitors.

[0087] In this article, "parallel" refers to a state where the angle formed by two straight lines is greater than -10° and less than 10°, and thus also includes a state where the angle is greater than -5° and less than 5°. Furthermore, "perpendicular" refers to a state where the angle formed by two straight lines is greater than 80° and less than 100°, and thus also includes a state where the angle is greater than 85° and less than 95°.

[0088] In this document, the terms "film" and "layer" can be interchanged. For example, "conductive layer" can sometimes be replaced with "conductive film." Similarly, "insulating film" can sometimes be replaced with "insulating layer."

[0089] The term "about" as used herein refers to a numerical value that is not strictly limited to a certain limit and is within a range of process and measurement errors.

[0090] Figure 1 is a schematic structural diagram of an OLED display device. As shown in Figure 1 , the OLED display device may include a scan signal driver, a data signal driver, a light emitting signal driver, an OLED display substrate, a first power supply unit, a second power supply unit, and an initial power supply unit. In an exemplary embodiment, the OLED display substrate includes at least a plurality of scan signal lines (S1 to SN), a plurality of data signal lines (D1 to DM), and a plurality of light emitting signal lines (EM1 to EMN). The scan signal driver is configured to sequentially provide scan signals to the plurality of scan signal lines (S1 to SN), the data signal driver is configured to provide data signals to the plurality of data signal lines (D1 to DM), and the light emitting signal driver is configured to sequentially provide light emitting control signals to the plurality of light emitting signal lines (EM1 to EMN). In an exemplary embodiment, the plurality of scan signal lines and the plurality of light emitting signal lines extend horizontally, while the plurality of data signal lines extend vertically. The display device includes a plurality of sub-pixels, with each sub-pixel being connected to, for example, one scan signal line, one light emitting control line, and one data signal line. The first power supply unit, the second power supply unit, and the initial power supply unit are configured to provide a first power supply voltage, a second power supply voltage, and an initial power supply voltage to the pixel circuit through a first power supply line, a second power supply line, and an initial signal line, respectively.

[0091] Figure 2 is a schematic diagram of a planar structure of a display area of ​​a display substrate. As shown in Figure 2, the display area may include a plurality of pixel units P arranged in a matrix. At least one of the plurality of pixel units P includes a first subpixel P1 that emits a first color light, a second subpixel P2 that emits a second color light, and a third subpixel P3 that emits a third color light. The first subpixel P1, the second subpixel P2, and the third subpixel P3 each include a pixel driving circuit and a light-emitting device. The pixel driving circuits in the first subpixel P1, the second subpixel P2, and the third subpixel P3 are respectively connected to a scan signal line, a data signal line, and a light-emitting signal line. The pixel driving circuits are configured to receive a data voltage transmitted by the data signal line under the control of the scan signal line and the light-emitting signal line and output a corresponding current to the light-emitting device. The light-emitting devices in the first subpixel P1, the second subpixel P2, and the third subpixel P3 are respectively connected to the pixel driving circuit of the subpixel. The light-emitting devices are configured to emit light of a corresponding brightness in response to the current output by the pixel driving circuit of the subpixel.

[0092] In an exemplary embodiment, the pixel unit P may include a red (R) sub-pixel, a green (G) sub-pixel, and a blue (B) sub-pixel, or may include a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white (W) sub-pixel, which is not limited in this disclosure. In an exemplary embodiment, the shape of the sub-pixels in the pixel unit may be rectangular, rhombus, pentagonal, or hexagonal. When the pixel unit includes three sub-pixels, the three sub-pixels may be arranged horizontally, vertically, or in a herringbone pattern. When the pixel unit includes four sub-pixels, the four sub-pixels may be arranged horizontally, vertically, or in a square pattern, which is not limited in this disclosure.

[0093] Figure 3 is a schematic cross-sectional view of a display substrate, illustrating the structure of three sub-pixels of an OLED display substrate. As shown in Figure 3, in a plane perpendicular to the display substrate, the display substrate may include a drive circuit layer 102 disposed on a substrate 101, a light-emitting device 103 disposed on the side of the drive circuit layer 102 facing away from the substrate 101, and an encapsulation layer 104 disposed on the side of the light-emitting device 103 facing away from the substrate 101. In some possible implementations, the display substrate may include other film layers, such as spacers, but this disclosure does not limit this.

[0094] In an exemplary embodiment, the substrate may be a flexible substrate or a rigid substrate. The flexible substrate may include a first flexible material layer, a first inorganic material layer, a semiconductor layer, a second flexible material layer, and a second inorganic material layer stacked together. The first flexible material layer and the second flexible material layer may be made of polyimide (PI), polyethylene terephthalate (PET), or a surface-treated polymer soft film. The first inorganic material layer and the second inorganic material layer may be made of silicon nitride (SiNx) or silicon oxide (SiOx) to improve the substrate's resistance to water and oxygen. The semiconductor layer may be made of amorphous silicon (a-Si).

[0095] In an exemplary embodiment, the driving circuit layer 102 of each sub-pixel may include multiple transistors and storage capacitors constituting a pixel driving circuit. FIG3 illustrates an example of each sub-pixel including one driving transistor and one storage capacitor. In some possible implementations, the driving circuit layer 102 of each sub-pixel may include: a first insulating layer 201 disposed on a substrate; an active layer disposed on the first insulating layer; a second insulating layer 202 covering the active layer; a gate electrode and a first capacitor electrode disposed on the second insulating layer 202; a third insulating layer 203 covering the gate electrode and the first capacitor electrode; a second capacitor electrode disposed on the third insulating layer 203; a fourth insulating layer 204 covering the second capacitor electrode, the second insulating layer 202, the third insulating layer 203, and the fourth insulating layer 204 having vias formed therein, the active layer exposed through the vias; a source electrode and a drain electrode disposed on the fourth insulating layer 204, the source electrode and the drain electrode respectively connected to the active layer through the vias; and a planar layer 205 covering the aforementioned structure, the planar layer 205 having vias formed therein, the drain electrode exposed through the vias. The active layer, the gate electrode, the source electrode and the drain electrode constitute the driving transistor 210 , and the first capacitor electrode and the second capacitor electrode constitute the storage capacitor 211 .

[0096] In an exemplary embodiment, the light-emitting device 103 may include an anode 301, a pixel definition layer 302, an organic light-emitting layer 303, and a cathode 304. The anode 301 is disposed on the planar layer 205 and is connected to the drain electrode of the driving transistor 210 through a via hole provided in the planar layer 205. The pixel definition layer 302 is disposed on the anode 301 and the planar layer 205, and a pixel opening is provided on the pixel definition layer 302, exposing the anode 301. The organic light-emitting layer 303 is at least partially disposed within the pixel opening and is connected to the anode 301. The cathode 304 is disposed on the organic light-emitting layer 303 and is connected to the organic light-emitting layer 303. The organic light-emitting layer 303 emits light of a corresponding color when driven by the anode 301 and the cathode 304.

[0097] In an exemplary embodiment, the encapsulation layer 104 may include a stacked first encapsulation layer 401, a second encapsulation layer 402 and a third encapsulation layer 403. The first encapsulation layer 401 and the third encapsulation layer 403 may be made of inorganic materials, and the second encapsulation layer 402 may be made of organic materials. The second encapsulation layer 402 is arranged between the first encapsulation layer 401 and the third encapsulation layer 403 to ensure that external water vapor cannot enter the light-emitting device 103.

[0098] In an exemplary embodiment, the organic light emitting layer 303 may include at least a hole injection layer 11 , a hole transport layer 20 , a light emitting layer 40 , and a hole blocking layer 50 stacked on the anode 301 .

[0099] FIG4 is a schematic diagram of the structure of an organic electroluminescent device according to an embodiment of the present disclosure, wherein the organic electroluminescent device includes an anode 10, a cathode 90, and a first hole transport layer 20 and a first light-emitting layer 40 disposed between the anode and the cathode, wherein the first hole transport layer 20 is located between the first light-emitting layer 40 and the anode 10; the first hole transport layer 20 includes at least a first hole sublayer 21 and a second hole sublayer 22; the material of the first hole sublayer 21 includes a first material and a second material, and the material of the second hole sublayer 22 includes at least one of the first material and the second material; and

[0100] Wherein, the first material is not limited to a compound having a structure of Formula 1:

[0101]

[0102] In formula 1:

[0103] X is O, S, C or N

[0104] L1 and L2 are each independently a direct bond, and each independently a substituted or unsubstituted C6-C60 aryl group;

[0105] Ar1 and Ar2 are each independently hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, an ester group, an imide group, an amino group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted alkylthio group, a substituted or unsubstituted arylthio group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted unsubstituted alkenyl, substituted or unsubstituted aralkyl, substituted or unsubstituted aralkenyl, substituted or unsubstituted alkylaryl, substituted or unsubstituted alkylamino, substituted or unsubstituted aralkylamino, substituted or unsubstituted heteroarylamino, substituted or unsubstituted arylamino, substituted or unsubstituted arylheteroarylamino, substituted or unsubstituted arylphosphino, substituted or unsubstituted phosphine oxide, substituted or unsubstituted aryl, or substituted or unsubstituted heterocyclic group; or represented by the following Formula 2:

[0106]

[0107] R1, R2, R3, and R4 are each independently selected from deuterium, a halogen group, a cyano group, a C3-C20 heteroaryl group, a C6-C20 aryl group, a C3-C12 trialkylsilyl group, a C18-C30 triarylsilyl group, a C1-C5 alkyl group, a C1-C10 haloalkyl group, a C3-C10 cycloalkyl group, a C2-C10 heterocycloalkyl group, a C5-C10 cycloalkenyl group, a C4-C10 heterocycloalkenyl group, a C1-C10 alkoxy group, a C1-C10 alkylthio group, a C6-C18 aryloxy group, a C6-C18 arylthio group, a C6-C24 phosphino group, a C6-C18 alkylsulfonyl group, a C3-C18 trialkylphosphino group, and a C3-C18 trialkylboryl group; or are optionally bonded to an adjacent group to form a ring;

[0108] a, b, m, and n are each independently an integer of 0-4.

[0109] The first hole sublayer 21 is located between the second hole sublayer 22 and the anode 10. The difference between the LUMO (Lowest Unoccupied Molecular Orbit) energy level of the first material and the HOMO (Highest Occupied Molecular Orbit) energy level of the second material is between -0.3 eV and 1.0 eV.

[0110] FIG5 is a schematic diagram of another exemplary organic electroluminescent device structure according to an embodiment of the present disclosure, wherein the organic electroluminescent device includes an anode 10, a cathode 90, and a first hole transport layer 20 and a first light-emitting layer 40 disposed between the anode and the cathode. The first hole transport layer 20 is located between the first light-emitting layer 40 and the anode 10. The first hole transport layer 20 includes at least a first hole sublayer 21 and a second hole sublayer 22. The material of the first hole sublayer 21 includes a first material and a second material, and the material of the second hole sublayer 22 includes at least one of the first material and the second material. The organic electroluminescent device also includes a first electron blocking layer 30, which is located between the first light-emitting layer 40 and the first hole transport layer 20. The difference between the HOMO energy level of the second hole sublayer material and the LUMO energy level of the first electron blocking layer is less than or equal to 0.4 eV. The difference between the LUMO energy level of the first electron blocking layer and the HOMO energy level of the first light-emitting layer is less than or equal to 0.4 eV. The mobility of the second hole sublayer material is greater than the mobility of the first electron blocking layer. A difference between a LUMO energy level of the first electron blocking layer and a HOMO energy level of the first light-emitting layer is less than or equal to 0.4 eV.

[0111] 6A and 6B are schematic structural diagrams of other exemplary organic electroluminescent devices according to embodiments of the present disclosure. In Figure 6A, the organic electroluminescent device includes an anode 10, a cathode 90, and a first hole transport layer 20 and a first light-emitting layer 40 arranged between the anode and the cathode, the first hole transport layer 20 is located between the first light-emitting layer 40 and the anode 10; the first hole transport layer 20 includes at least a first hole sublayer 21 and a second hole sublayer 22; the material of the first hole sublayer 21 includes a first material and a second material, and the material of the second hole sublayer 22 includes at least one of the first material and the second material; and the organic electroluminescent device also includes a first electron blocking layer 30, the first electron blocking layer 30 is located between the first light-emitting layer 40 and the first hole transport layer 20, the difference between the HOMO energy level of the second hole sublayer material and the LUMO energy level of the first electron blocking layer is less than or equal to 0.4 eV; the difference between the LUMO energy level of the first electron blocking layer and the HOMO energy level of the first light-emitting layer is less than or equal to 0.4 eV; and the first electron blocking layer 30 includes a first blocking sublayer 31. In FIG6B , the organic electroluminescent device comprises an anode 10, a cathode 90, and a first hole transport layer 20 and a first light-emitting layer 40 disposed between the anode and the cathode, wherein the first hole transport layer 20 is located between the first light-emitting layer 40 and the anode 10; the first hole transport layer 20 comprises at least a first hole sublayer 21 and a second hole sublayer 22; the material of the first hole sublayer 21 comprises a first material and a second material, and the material of the second hole sublayer 22 comprises at least one of the first material and the second material; and the organic electroluminescent device further comprises a first electron blocking layer 30, the first The electron blocking layer 30 is located between the first light-emitting layer 40 and the first hole transport layer 20, and the difference between the HOMO energy level of the second hole sublayer material and the LUMO energy level of the first electron blocking layer is less than or equal to 0.4 eV; the difference between the LUMO energy level of the first electron blocking layer and the HOMO energy level of the first light-emitting layer is less than or equal to 0.4 eV; and the first electron blocking layer 30 includes a first blocking sublayer 31 and a second blocking sublayer 32, the second blocking sublayer is located between the first blocking sublayer and the first light-emitting layer, and the material of the first blocking sublayer is different from the material of the second blocking sublayer.

[0112] In an exemplary embodiment of the present disclosure, the resistivity of the first hole sub-layer 21 is greater than or equal to 100Ω·m.

[0113] FIG7 is a schematic diagram of another exemplary structure of an organic electroluminescent device according to an embodiment of the present disclosure, wherein the organic electroluminescent device further includes a charge generation layer 60, a second hole transport layer 20′, and a second light-emitting layer 40′, wherein the charge generation layer 60 is located on the side of the first light-emitting layer 40 close to the cathode, the second hole transport layer 20′ is located on the side of the charge generation layer close to the cathode, and the second light-emitting layer 40′ is located between the second hole transport layer 20′ and the cathode; the second hole transport layer 20′ includes at least a third hole sublayer 21′, the material of the third hole sublayer 21′ includes a first material and a second material; the third hole sublayer 21′ is located between the second light-emitting layer 40′ and the charge generation layer 60; the mobility M2 of the material of the second hole sublayer 22 and the mobility M4 of the material of the third hole sublayer 21′ satisfy the following conditions:

[0114] 10 -1 cm 2 / Vs≤M2 / M4≤10cm 2 / Vs; and

[0115] The organic electroluminescent device also includes a second electron blocking layer 30', which is located between the second light-emitting layer 40' and the second hole transport layer 20'. The difference between the HOMO energy level of the material of the third hole sublayer 21' and the LUMO energy level of the second electron blocking layer 30' is less than or equal to 0.4 eV; the mobility of the material of the third hole sublayer 21' is greater than the mobility of the second electron blocking layer 30'; and the difference between the LUMO energy level of the fourth blocking sublayer 32' and the HOMO energy level of the second light-emitting layer is less than or equal to 0.4 eV.

[0116] Figures 8A and 8B are schematic diagrams of other exemplary organic electroluminescent device structures according to embodiments of the present disclosure. In Figure 8A , the organic electroluminescent device further includes a second electron blocking layer 30', which includes a third blocking sublayer 31'. In Figure 8B , the organic electroluminescent device further includes a second electron blocking layer 30', which includes a third blocking sublayer 31' and a fourth blocking sublayer 32'. The fourth blocking sublayer 32' is located between the third blocking sublayer 31' and the second light-emitting layer 40', and the material of the third blocking sublayer 31' is different from that of the fourth blocking sublayer 32'.

[0117] FIG9 is a schematic diagram of another exemplary structure of an organic electroluminescent device according to an embodiment of the present disclosure, comprising an anode 10, a cathode 90, and a first hole transport layer 20 and a first light-emitting layer 40 disposed between the anode and the cathode, wherein the first hole transport layer 20 is located between the first light-emitting layer 40 and the anode 10; the first hole transport layer 20 comprises at least a first hole sublayer 21 and a second hole sublayer 22; the material of the first hole sublayer 21 comprises a first material and a second material, and the material of the second hole sublayer 22 comprises at least one of the first material and the second material; and the organic electroluminescent device further comprises a first electron blocking layer 30, the first electron blocking layer 30 being located between the first light-emitting layer 40 and the first hole transport layer 20, the difference between the HOMO energy level of the second hole sublayer material and the LUMO energy level of the first electron blocking layer being less than or equal to 0.4 eV; the difference between the LUMO energy level of the first electron blocking layer and the HOMO energy level of the first light-emitting layer being less than or equal to 0.4 eV; and the first electron blocking layer 30 comprises a first blocking sublayer 31 and a first blocking sublayer 32; (wherein 41 is a light-emitting layer 1, which can emit red light; 42 is a light-emitting layer 2, which can emit green light; 43 is a light-emitting layer 3, which can emit blue light; and each light-emitting layer is provided with a corresponding electron blocking sublayer 32-1, 32-2 or 32-3); the organic electroluminescent device further comprises a charge generation layer 60 (61 is an N-type charge generation layer, 62 is a P-type charge generation layer), a second hole transport layer 20' and a second light-emitting layer 40', the charge generation layer 60 is located on the side of the first light-emitting layer 40 close to the cathode, the second hole transport layer 20' is located on the side of the first light-emitting layer 40 close to the cathode, and ... The second hole transport layer 20' is located on the side of the charge generation layer close to the cathode, and the second light-emitting layer 40' is located between the second hole transport layer 20' and the cathode; the second hole transport layer 20' includes at least a third hole sublayer 21', and the material of the third hole sublayer 21' includes a first material and a second material; the third hole sublayer 21' is located between the second light-emitting layer 40' and the charge generation layer 60; the mobility M2 of the material of the second hole sublayer 22 and the mobility M4 of the material of the third hole sublayer 21' meet the following conditions:

[0118] 10 -1 cm 2 / Vs≤M2 / M4≤10cm 2 / Vs; and

[0119] The organic electroluminescent device also includes a second electron blocking layer 30', which is located between the second light-emitting layer 40' and the second hole transport layer 20'. The difference between the HOMO energy level of the material of the third hole sublayer 21' and the LUMO energy level of the second electron blocking layer 30' is less than or equal to 0.4 eV; the mobility of the material of the third hole sublayer 21' is greater than the mobility of the second electron blocking layer 30'; and the difference between the LUMO energy level of the fourth blocking sublayer 30' and the HOMO energy level of the second light-emitting layer is less than or equal to 0.4 eV. The organic electroluminescent device also includes a second electron blocking layer 30', which includes a third blocking sublayer 31' and a fourth blocking sublayer 32'. The fourth blocking sublayer 32' is located between the third blocking sublayer 31' and the second light-emitting layer 40'. The material of the third blocking sublayer 31' is different from that of the fourth blocking sublayer 32' (wherein 41' is the light-emitting layer 1, which can emit red light; 42' is the light-emitting layer 2, which can emit green light; 43' is the light-emitting layer 3, which can emit blue light; and each light-emitting layer is provided with its own corresponding electron blocking sublayer 32'-1, 32'-2 or 32'-3).

[0120] FIG10 is a schematic diagram of another exemplary organic electroluminescent device structure according to an embodiment of the present disclosure, comprising an anode 10, a cathode 90, and a first hole transport layer 20 and a first light-emitting layer 40 disposed between the anode and the cathode, wherein the first hole transport layer 20 is located between the first light-emitting layer 40 and the anode 10; the first hole transport layer 20 comprises at least a first hole sublayer 21 and a second hole sublayer 22; the material of the first hole sublayer 21 comprises a first material and a second material, and the material of the second hole sublayer 22 comprises at least one of the first material and the second material; and the organic electroluminescent device further comprises a first electron blocking layer 30, the first electron blocking layer 30 being located between the first light-emitting layer 40 and the first hole transport layer 20, the difference between the HOMO energy level of the second hole sublayer material and the LUMO energy level of the first electron blocking layer being less than or equal to 0.4 eV; the difference between the LUMO energy level of the first electron blocking layer and the HOMO energy level of the first light-emitting layer being less than or equal to 0.4 eV; and the first electron blocking layer 30 comprises a first blocking sublayer 31 and a first blocking sublayer 32. 2; (wherein 41 is a light-emitting layer 1, which can emit red light, green light or blue light; 42 is a light-emitting layer 2, which can emit red light, green light or blue light; 43 is a light-emitting layer 3, which can emit red light, green light or blue light; and each light-emitting layer is provided with a corresponding electron blocking sublayer 32-1, 32-2 or 32-3); the organic electroluminescent device further includes a charge generation layer 60 (61 is an N-type charge generation layer, 62 is a P-type charge generation layer), a second hole transport layer 20' and a second light-emitting layer 40', the charge generation layer 60 is located on the first light-emitting layer 40 close to the cathode On the other hand, the second hole transport layer 20' is located on the side of the charge generation layer close to the cathode, and the second light-emitting layer 40' is located between the second hole transport layer 20' and the cathode; the second hole transport layer 20' includes at least a third hole sublayer 21', and the material of the third hole sublayer 21' includes a first material and a second material; the third hole sublayer 21' is located between the second light-emitting layer 40' and the charge generation layer 60; the mobility M2 of the material of the second hole sublayer 22 and the mobility M4 of the material of the third hole sublayer 21' satisfy the following conditions:

[0121] 10 -1 cm 2 / Vs≤M2 / M4≤10cm 2 / Vs; and

[0122] The organic electroluminescent device also includes a second electron blocking layer 30', which is located between the second light-emitting layer 40' and the second hole transport layer 20'. The difference between the HOMO energy level of the material of the third hole sublayer 21' and the LUMO energy level of the second electron blocking layer 30' is less than or equal to 0.4 eV; the mobility of the material of the third hole sublayer 21' is greater than the mobility of the second electron blocking layer 30'; and the difference between the LUMO energy level of the fourth blocking sublayer 30' and the HOMO energy level of the second light-emitting layer is less than or equal to 0.4 eV. The organic electroluminescent device also includes a second electron blocking layer 30', which includes a third blocking sublayer 31' and a fourth blocking sublayer 32'. The fourth blocking sublayer 32' is located between the third blocking sublayer 31' and the second light-emitting layer 40'. The material of the third blocking sublayer 31' is different from that of the fourth blocking sublayer 32' (wherein 41' is the light-emitting layer 1, which can emit red light, green light or blue light; 42' is the light-emitting layer 2, which can emit red light, green light or blue light; 43' is the light-emitting layer 3, which can emit red light, green light or blue light; and each light-emitting layer is provided with its own corresponding electron blocking sublayer 32'-1, 32'-2 or 32'-3).

[0123] Figure 11 is a schematic diagram of the structure of another organic electroluminescent device according to an embodiment of the present disclosure. The main structure of the device in this figure is similar to the main structure of the device in Figure 10, except that: 41 is the light-emitting layer 1, which can emit red light, green light or blue light; 42 is the light-emitting layer 2, which can emit red light, green light or blue light; 43 is the light-emitting layer 3, which can emit red light, green light or blue light; and 41 is located above 42 and 43, and 41 is provided with a corresponding electron blocking sublayer 32-1; 41' is the light-emitting layer 1, which can emit red light, green light or blue light; 42' is the light-emitting layer 2, which can emit red light, green light or blue light; 43' is the light-emitting layer 3, which can emit red light, green light or blue light; and 41' is located above 42' and 43', and 41' is provided with a corresponding electron blocking sublayer 32'-1.

[0124] Figure 12 illustrates an example of crosstalk. The vertical axis represents light intensity, while the horizontal axis represents wavelength. The wavelength range for blue light is 440nm-475nm, for green light is 492nm-577nm, and for red light is 622nm-760nm. As can be seen from the figure, when the light-emitting layer is operating, electrons from the intermediate green wavelength flow laterally into the peak of the red wavelength on the right, creating a smaller peak.

[0125] Figure 13 shows an exemplary crosstalk-free light spectrum of the device disclosed herein. The vertical axis represents light intensity, while the horizontal axis represents wavelength. The wavelength range for blue light is 440nm-475nm, the wavelength range for green light is 492nm-577nm, and the wavelength range for red light is 622nm-760nm. As can be seen from the figure, the light-emitting device disclosed herein can effectively reduce crosstalk and improve display quality.

[0126] In an exemplary embodiment, the organic light-emitting layer of an OLED light-emitting element may include an emitting layer (EML), and one or more layers selected from the group consisting of a hole injection layer (HIL), a hole transport layer (HTL), a hole blocking layer (HBL), an electron blocking layer (EBL), an electron injection layer (EIL), and an electron transport layer (ETL). Driven by voltages from the anode and cathode, the organic material's luminescence properties are utilized to produce light in a desired grayscale.

[0127] In an OLED structure, the material used for the hole injection layer HIL can be selected from inorganic oxides, such as molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, manganese oxide, etc.; it can also be selected from dopants of a strong electron-withdrawing system, such as F4TCNQ, HATCN, etc.

[0128] In another OLED structure, the charge generation layer includes a P-type charge generation layer (CGL) and an N-type CGL. The P-type CGL can be a hole-type material such as NPB, TPD, etc., and the N-type charge generation layer can be an electron-type material containing phenanthroline or phosphine oxide. Both the P-type CGL and the N-type CGL can contain dopants. The dopant of the P-type charge generation layer can be HATCN, F4TCNQ, etc., and the dopant of the N-type charge generation layer can be an alkali metal such as lithium (Li), sodium (Na), potassium (K), or cesium (Cs), or an alkali metal or alkaline earth metal such as magnesium (Mg), strontium (Sr), barium (Ba), or radium (Ra), and their oxides. As an N-type CGL, electrons can be injected into the first light-emitting unit. As a P-type CGL, holes can be injected into the second light-emitting unit.

[0129] In another OLED structure, the electron injection layer is generally an alkali metal or metal, such as LiF, Yb, Mg, Ca or their compounds.

[0130] In another OLED structure, the indium tin oxide (ITO) layer on the glass substrate serves as the anode, the hole injection layer (5-30 nm), the first hole sublayer (15-25 nm), the second hole sublayer (5-45 nm), the third hole sublayer (10-25 nm), the red light emitting layer (30-50 nm), the green light emitting layer (30-50 nm), the blue light emitting layer (10-20 nm), the first hole blocking layer (5-15 nm), and the N-type charge generation layer (15-25 nm) are used. , P-type charge generation layer (5-15nm), first hole sublayer (15-25nm), second hole sublayer (5-45nm), third hole sublayer GEBL (10-25nm), red light emitting layer (30-50nm), green light emitting layer (30-50nm), blue light emitting layer (10-20nm), second blocking sublayer (5-15nm), electron transport layer (20-100nm), electron injection layer (1-10nm), cathode (10-20nm).

[0131] In another OLED structure, the physical properties of the layers of the stacked organic light-emitting device are as follows:

[0132] (1) Both the first and second EML layers contain three RGB light-emitting layers, and the wavelength difference between the two layers of the same color is less than or equal to 20nm, ensuring that there is no obvious color difference between the two light-emitting layers;

[0133] When two light-emitting units contain only one light-emitting layer, the light-emitting layer can emit red light, green light, or blue light. When containing three light-emitting layers, they can emit red light, blue light, or green light.

[0134] (2) The difference between the LUMO energy level of the first material and the HOMO energy level of the second material is between -0.3 eV and 1.0 eV;

[0135] The difference between the HOMO energy level of the second hole sublayer material and the LUMO energy level of the first electron blocking layer is less than or equal to 0.4 eV, ensuring smooth carrier transmission;

[0136] The difference between the LUMO energy level of the first electron blocking layer and the HOMO energy level of the first light-emitting layer is less than or equal to 0.4 eV, ensuring that holes are well injected into the light-emitting layer;

[0137] (3) The mobility of the second hole sublayer material is greater than that of the first electron blocking layer. The second hole sublayer has a larger mobility in the thickness direction of the electron blocking layer, which can prevent the problem of high voltage and ensure the device voltage and performance;

[0138] The mobility M2 of the second hole sublayer (HTL-1) material in the first light-emitting unit and the mobility M4 of the third hole sublayer (HTL-2) material in the second light-emitting unit meet the following conditions:

[0139] 10 -1 cm 2 / Vs≤M2 / M4≤10cm 2 / Vs, so that there is no obvious difference in the composite area of ​​the two EML layers;

[0140] (4) Resistivity of the hole injection layer: ≥100Ω·m, lateral current of the hole transport layer, solving the color crosstalk problem between light-emitting units.

[0141] Table 1 Commonly used commercial materials for each functional layer

[0142]

[0143]

[0144] N-CGL can be expressed as follows:

[0145]

[0146] In Formula 5, R1 to R7 are the same or different and are each independently selected from any one of the following: hydrogen; deuterium; tritium; halogen; cyano; nitro; C6-C60 aryl; C2-C60 heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P; a fused ring group of a C3-C60 aliphatic ring and a C6-C60 aromatic ring; C1-C50 alkyl; C2-C20 alkenyl; C2-C20 alkynyl; C1-C30 alkoxy; C6-C30 aryloxy; C3-C60 alkylsilyl; C18-C60 arylsilyl; and C8-C60 alkylarylsilyl; and one or more of R1 to R6 are cyano;

[0147] Ar is each independently any one selected from the following: hydrogen; deuterium; tritium; halogen; cyano; nitro; C6-C60 aryl; C2-C60 heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P; a fused ring group of a C3-C60 aliphatic ring and a C6-C60 aromatic ring; C1-C50 alkyl; C2-C20 alkenyl; C2-C20 alkynyl; C1-C30 alkoxy; C6-C30 aryloxy; C3-C60 alkylsilyl; C18-C60 arylsilyl; and C8-C60 alkylarylsilyl;

[0148] L is selected from any one of the following: a C6-C60 arylene group; a C2-C60 divalent heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P; and a divalent condensed cyclic group of a C3-C60 aliphatic ring and a C6-C60 aromatic ring.

[0149] The compound of formula 5 is selected from one or more of the following compounds:

[0150]

[0151] Resistivity test

[0152] The structure used in the resistivity test in the table below is: lateral resistance substrate / P-type doped hole injection layer / hole transport layer. The film resistivity can reflect the resistivity of the compound.

[0153] Table 2 Comparison of properties of various compounds

[0154]

[0155] As can be seen from the results in the table, the compound of Formula 1 in the present invention has an electron-rich unit, and the conjugation length within the molecule can be effectively adjusted by the connection between the groups. Its reorganization energy is lower and it has a high hole mobility. A higher HOMO energy level is more suitable; it enables better hole transmission. Through the specific connection between the groups, the spatial structure of this type of molecule is made three-dimensional, and the deposited film has a greater lateral resistance. The color crosstalk is mainly caused by the lateral leakage of the hole injection layer. Therefore, the compound of Formula 1 has a large lateral resistance as a hole transport material after P-type doping, which can well solve the lateral diffusion of charges between different colors of light, greatly reduce the color crosstalk problem, and improve the display effect.

[0156] The compound of Formula 3 has a deeper HOMO energy level than the comparative compound and a deeper HOMO energy level than the compound of Formula 2. This significantly reduces the potential barrier between the hole transport layer and the light-emitting layer, facilitating carrier transport. Furthermore, it has a greater lateral resistance than the comparative compound, further improving color crosstalk.

[0157] Functional layer materials used in the examples

[0158]

[0159] Table 3 EL devices prepared in the present disclosure

[0160] No. First hole transport layer Second hole transport layer EBLNCGL Example 1 1-2 and 3-6 3-64-25-1 Example 2 1-3 and 3-63-64-15-1 Example 3 1-2 and 3-6 comparison REBL 4-25-1 Example 4 1-2 and 3-63-64-2 comparison NCGL Example 5 1-2 and 3-6 comparison HTL 4-2 comparison NCGL Example 6 comparison HIL and comparison HTL 3-64-25-1 Comparative Example 1 comparison HIL and comparison HTL comparison HTL comparison EBL comparison NCGL

[0161] Table 4 Parameters of the EL devices in Table 3 above

[0162] No. Voltage Efficiency Lifetime EL Spectrum CIExCIEy Example 1 94.89% 115.06% 115.02% 6250.6850.315 Example 2 95.63% 110.77% 111.62% 6250.6840.315 Example 3 96.06% 106.85% 106.14% 6250.6850.316 Example 4 96.29% 104.72% 105.51% 6260.6850.316 Example 5 99.08% 103.21% 102.78% 6260.6860.315 Example 6 99.83% 102.06% 101.87% 6240.6830.317 Comparative Example 1 100% 100% 100% 6260.6850.315

[0163] Although the embodiments disclosed in this disclosure are as described above, the contents described are merely embodiments adopted to facilitate understanding of the disclosure and are not intended to limit the disclosure. Any person skilled in the art may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope of the disclosure. However, the scope of patent protection of this application shall still be based on the scope defined by the attached claims.

Claims

1. An organic electroluminescent device comprising an anode, a cathode, and a first hole transport layer and a first light-emitting layer disposed between the anode and the cathode, wherein the first hole transport layer is located between the first light-emitting layer and the anode; the first hole transport layer comprises at least a first hole sublayer and a second hole sublayer; the first hole sublayer comprises a first material and a second material, and the second hole sublayer comprises at least one of the first material and the second material; and in, The first material includes but is not limited to a compound having a structure of Formula 1: In formula 1: X is O, S, C or N L1 and L2 are each independently a direct bond, and each independently a substituted or unsubstituted C6-C60 aryl group; Ar1 and Ar2 are each independently hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, an ester group, an imide group, an amino group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted alkylthio group, a substituted or unsubstituted arylthio group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted unsubstituted alkenyl, substituted or unsubstituted aralkyl, substituted or unsubstituted aralkenyl, substituted or unsubstituted alkylaryl, substituted or unsubstituted alkylamino, substituted or unsubstituted aralkylamino, substituted or unsubstituted heteroarylamino, substituted or unsubstituted arylamino, substituted or unsubstituted arylheteroarylamino, substituted or unsubstituted arylphosphino, substituted or unsubstituted phosphine oxide, substituted or unsubstituted aryl, or substituted or unsubstituted heterocyclic group; or represented by the following Formula 2: R1, R2, R3, and R4 are each independently selected from deuterium, a halogen group, a cyano group, a C3-C20 heteroaryl group, a C6-C20 aryl group, a C3-C12 trialkylsilyl group, a C18-C30 triarylsilyl group, a C1-C5 alkyl group, a C1-C10 haloalkyl group, a C3-C10 cycloalkyl group, a C2-C10 heterocycloalkyl group, a C5-C10 cycloalkenyl group, a C4-C10 heterocycloalkenyl group, a C1-C10 alkoxy group, a C1-C10 alkylthio group, a C6-C18 aryloxy group, a C6-C18 arylthio group, a C6-C24 phosphino group, a C6-C18 alkylsulfonyl group, a C3-C18 trialkylphosphino group, and a C3-C18 trialkylboryl group; or are optionally bonded to an adjacent group to form a ring; a, b, m, and n are each independently an integer of 0-4.

2. The organic electroluminescent device according to claim 1, wherein The first hole sublayer is located between the second hole sublayer and the anode.

3. The organic electroluminescent device according to claim 1, wherein The difference between the LUMO energy level of the first material and the HOMO energy level of the second material is between -0.3 eV and 1.0 eV.

4. The organic electroluminescent device according to claim 1, wherein The organic electroluminescent device further includes a first electron blocking layer, which is located between the first light-emitting layer and the first hole transport layer, and the difference between the HOMO energy level of the second hole sublayer material and the LUMO energy level of the first electron blocking layer is less than or equal to 0.4 eV.

5. The organic electroluminescent device according to claim 4, wherein The mobility of the second hole sublayer material is greater than the mobility of the first electron blocking layer. The organic electroluminescent device according to claim 4 , wherein: A difference between a LUMO energy level of the first electron blocking layer and a HOMO energy level of the first light-emitting layer is less than or equal to 0.4 eV.

7. The organic electroluminescent device according to claim 4, wherein: The first electron blocking layer includes a first blocking sublayer, or the first electron blocking layer includes a first blocking sublayer and a second blocking sublayer, the second blocking sublayer is located between the first blocking sublayer and the first light-emitting layer, and the material of the first blocking sublayer is different from that of the second blocking sublayer.

8. The organic electroluminescent device according to claim 1, wherein The resistivity of the first hole sub-layer is greater than or equal to 100Ω·m.

9. The organic electroluminescent device according to claim 1, wherein The organic electroluminescent device also includes a charge generation layer, a second hole transport layer and a second light-emitting layer, the charge generation layer is located on the side of the first light-emitting layer close to the cathode, the second hole transport layer is located on the side of the charge generation layer close to the cathode, and the second light-emitting layer is located between the second hole transport layer and the cathode; the second hole transport layer includes at least a third hole sublayer, and the material of the third hole sublayer includes a first material and a second material.

10. The organic electroluminescent device according to claim 9, wherein: The third hole sublayer is located between the second light-emitting layer and the charge generation layer.

11. The organic electroluminescent device according to claim 9, wherein The mobility M2 of the second hole sub-layer material and the mobility M4 of the third hole sub-layer material satisfy the following conditions: 10 -1 cm 2 / Vs≤M2 / M4≤10cm 2 / Vs。 12. The organic electroluminescent device according to claim 9, wherein: The organic electroluminescent device also includes a second electron blocking layer, which includes a third blocking sublayer, or the second electron blocking layer includes a third blocking sublayer and a fourth blocking sublayer. The second electron blocking layer is located between the second light-emitting layer and the second hole transport layer, and the difference between the HOMO energy level of the third hole sublayer material and the LUMO energy level of the second electron blocking layer is less than or equal to 0.4 eV.

13. The organic electroluminescent device according to claim 12, wherein: The mobility of the third hole sublayer material is greater than the mobility of the second electron blocking layer.

14. The organic electroluminescent device according to claim 12, wherein: A difference between a LUMO energy level of the fourth blocking sublayer and a HOMO energy level of the second light-emitting layer is less than or equal to 0.4 eV.

15. The organic electroluminescent device according to claim 12, wherein: The second electron blocking layer includes a third blocking sublayer, or the second electron blocking layer includes a third blocking sublayer and a fourth blocking sublayer, the fourth blocking sublayer is located between the third blocking sublayer and the second light-emitting layer, and the material of the third blocking sublayer is different from that of the fourth blocking sublayer.

16. The organic electroluminescent device according to any one of claims 1 to 15, wherein The compound of formula 1 is selected from one or more of the following compounds:

17. The organic electroluminescent device according to any one of claims 1 to 15, wherein The second material includes but is not limited to a compound having a structure of Formula 3: In formula 3: A1-A6 are each independently substituted or unsubstituted halogen, substituted or unsubstituted cyano, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, and aryl substituted by an electron-deficient group or heteroaryl substituted by an electron-deficient group; A is a 3-membered ring, a 4-membered ring, a 5-membered ring or a 6-membered ring.

18. The organic electroluminescent device according to claim 17, wherein: The compound of formula 3 is selected from one or more of the following compounds:

19. The organic electroluminescent device according to claim 4, wherein: The electron blocking layer includes but is not limited to compounds having a structure of Formula 4: In Formula 4, Ar3, Ar4, Ar5, and Ar6 are each independently a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group; L1, L2, L3, and L4 are each independently a direct bond, and each independently a substituted or unsubstituted C6-C60 aryl group; R5 and R6 are each independently selected from deuterium, a halogen group, a cyano group, a C3-C20 heteroaryl group, a C6-C20 aryl group, a C3-C12 trialkylsilyl group, a C18-C30 triarylsilyl group, a C1-C5 alkyl group, a C1-C10 haloalkyl group, a C3-C10 cycloalkyl group, a C2-C10 heterocycloalkyl group, a C5-C10 cycloalkenyl group, a C4-C10 heterocycloalkenyl group, a C1-C10 alkoxy group, a C1-C10 alkylthio group, a C6-C18 aryloxy group, a C6-C18 arylthio group, a C6-C24 phosphino group, a C6-C18 alkylsulfonyl group, a C3-C18 trialkylphosphino group, a C3-C18 trialkylboryl group; or optionally bonded to an adjacent group to form a ring; Ar3, Ar4, Ar5, Ar6 are each independently the following groups:

20. A display device comprising the organic electroluminescent device according to any one of claims 1 to 19.

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