Light-emitting device and display panel comprising same, and display apparatus

Abstract

Provided in the present disclosure are a light-emitting device and a display panel comprising same, and a display apparatus. The light-emitting device comprises: a first carrier layer, a light-emitting layer and a second carrier layer, which are arranged in a stacked manner, wherein the light-emitting layer comprises a first light-emitting layer, a second light-emitting layer and a third light-emitting layer, which are arranged in a stacked manner, with the first light-emitting layer being arranged close to the first carrier layer, and the first light-emitting layer and the third light-emitting layer have different carrier transport rates. The light-emitting device of the present disclosure has a structure of three light-emitting layers, wherein the first light-emitting layer which is close to an anode side has a good hole injection / transport capability, the third light-emitting layer which is close to a cathode side has a good electron injection / transport capability, and the second light-emitting layer in the middle has a good hole and electron transport capability. Electrons and holes can be better injected into the light-emitting layers, an exciton recombination zone can also be broadened, and a larger part of the recombination zone is made to be within the light-emitting layers, so as to reduce the energy loss of non-radiative transition, thereby improving the efficiency and stability of devices.

Description

A light-emitting device, a display panel including the light-emitting device, and a display device.

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202410703213.4, filed in China on May 31, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure belongs to the technical field of organic electroluminescent devices, and specifically relates to a light-emitting device, a display panel including the same, and a display device. Background Technology

[0004] Organic light-emitting diode (OLED) displays have become the mainstream new generation of flat panel displays due to their advantages such as self-illumination, low power consumption, high resolution, wide color gamut, no need for backlight, and flexibility. Summary of the Invention

[0005] In a first aspect, this disclosure provides a light-emitting device, comprising: a first carrier layer, a light-emitting layer and a second carrier layer stacked together, wherein the light-emitting layer comprises a first light-emitting layer, a second light-emitting layer and a third light-emitting layer stacked together, the first light-emitting layer being disposed close to the first carrier layer, and the carrier transport rates of the first light-emitting layer and the third light-emitting layer being different.

[0006] Optionally, the hole transport rate of the first light-emitting layer is greater than that of the third light-emitting layer, and the electron transport rate of the first light-emitting layer is less than that of the third light-emitting layer.

[0007] Optionally, the first light-emitting layer includes a first host material and a first object material, the second light-emitting layer includes a first host material, a second host material and a second object material, and the third light-emitting layer includes a second host material and a third object material, wherein the first host material and the second host material are different.

[0008] Optionally, the first light-emitting layer includes a first host material, a second host material, a third host material, and a first object material; the second light-emitting layer includes a first host material, a second host material, and a second object material; and the third light-emitting layer includes a first host material, a second host material, a fourth host material, and a third object material, wherein the first host material, the second host material, the third host material, and the fourth host material are different.

[0009] Optionally, in the first light-emitting layer, the second light-emitting layer, and the third light-emitting layer, at least one of the main materials contains a carbazole group.

[0010] Optionally, the first host material includes: a compound having chemical formula I, the structure of which is:

[0011] A11 is selected from one of chemical formulas 1, 2, and 3:

[0012] Where * represents the connection site between A11 and chemical formula I, and R111-R119 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 Aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic group, -LN-(Ar1)(Ar2) or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings; n111, n112 and n119 are integers from 0 to 4, n113-118 are integers from 0 to 5, and when n111-n119 are integers greater than 1, each R111-R119 may be the same or different;

[0013] L11 is independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0014] R11-R18 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic, -LN-(Ar1)(Ar2), or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings;

[0015] Ar1 and Ar2 are each independently selected from hydrogen, deuterium, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic group, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring.

[0016] Optionally, the second host material includes: a compound having chemical formula II, wherein the structure of chemical formula II is:

[0017] Wherein, Har is a substituted or unsubstituted 3-30 member heteroaryl group;

[0018] L12 is independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0019] R21-R28 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic, -LN-(Ar1)(Ar2), or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings;

[0020] Har is selected from one of the chemical formulas 4, 5, 6 and 7;

[0021] Wherein, * represents the connection site between Har and chemical formula II; X21-X39 are each independently selected from CR2 or N, and at least one of X21-X23 is N, at least one of X24-X31 is N, and at least one of X32-X39 is N; Y is independently selected from NR44, CR45R46, O, S, or Se; Ar21 and Ar22 each independently represent hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3- C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring; L independently represents a single bond, substituted or unsubstituted C1-C30 alkylene, substituted or unsubstituted C6-C30 arylene, substituted or unsubstituted 5-30-membered heteroarylene, or substituted or unsubstituted C3-C30 cycloalkylene;

[0022] R2 and R29 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic, -LN-(Ar1)(Ar2), or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings; n29 is an integer from 0 to 7, and when n29 is an integer greater than 1, each R29 is the same or different;

[0023] Ar1 and Ar2 are each independently selected from hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic group, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring;

[0024] L is independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0025] Optionally, the third host material includes: a compound having chemical formula III, wherein the structure of chemical formula III is:

[0026] Among them, L31-L33 are each independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0027] Ar31-Ar33 are each independently selected from hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic group, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring.

[0028] Optionally, the fourth host material includes: a compound having chemical formula IV, wherein the structure of chemical formula IV is:

[0029] R41-R43 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic, -LN-(Ar1)(Ar2), or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings;

[0030] n41-n43 are integers from 0 to 5, and when n41-n43 are integers greater than 1, each R41-R43 is either the same or different;

[0031] Ar1 and Ar2 each independently represent hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic group, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring;

[0032] L is independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0033] Optionally, the first charge carrier layer includes a first hole transport layer, the second charge carrier layer includes a first electron transport layer, and further includes: a first light-emitting region, the first light-emitting region being disposed on the side of the first electron transport layer away from the light-emitting layer; the first light-emitting region includes: a charge generation layer, a second hole transport layer, a fourth light-emitting layer, and a second electron transport layer stacked together, the charge generation layer being disposed close to the first electron transport layer.

[0034] Optionally, the first charge carrier layer includes a first hole transport layer, the second charge carrier layer includes a first electron transport layer, and further includes a second light-emitting region disposed on the side of the first hole transport layer away from the light-emitting layer; the second light-emitting region includes a third hole transport layer, a fifth light-emitting layer, a third electron transport layer, and a charge generation layer stacked together, the charge generation layer being disposed close to the first hole transport layer.

[0035] Secondly, this disclosure provides a display panel including the light-emitting device described above.

[0036] Thirdly, this disclosure provides a display device, including the display panel described above. Attached Figure Description

[0037] Figure 1 is a schematic diagram of the first structure of the light-emitting device in this disclosure;

[0038] Figure 2 is a second structural schematic diagram of the light-emitting device in this disclosure;

[0039] Figure 3 is a third structural schematic diagram of the light-emitting device in this disclosure.

[0040] Reference numerals: Substrate 0; Anode 1; First hole transport layer 2; First light-emitting layer 3-1; Second light-emitting layer 3-2; Third light-emitting layer 3-3; First electron transport layer 4; Cathode 5; Light extraction area 6; Charge generation layer 7; Second hole transport layer 8; Fourth light-emitting layer 9; Second electron transport layer 10; Fifth light-emitting layer 11; Third hole transport layer 12; Third electron transport layer 13. Detailed Implementation

[0041] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0042] The terms "first," "second," etc., used in this disclosure and in the claims are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this disclosure can be implemented in orders other than those illustrated or described herein. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0043] The English abbreviations and non-common terms appearing in this disclosure are given their corresponding Chinese names and meanings as follows:

[0044] OLED: Organic Light Emitting Diode; HIL: Hole Injection Layer; HTL: Hole Transport Layer; EBL (B-prime): Electron Blocking Layer; BH: Blue Light Host; BH-P: Blue Light Hole Host; BH-N: Blue Light Electron Host; BD: Blue Light Dopant; EML: Emitting Layer; HBL: Hole Blocking Layer; ETL: Electron Transport Layer; EIL: Electron Injection Layer; HOMO: Highest Occupied Molecular Orbital; LUMO: Lowest Unoccupied Molecular Orbital; T1: Lowest Triplet Level; S1: Lowest Singlet Level.

[0045] Currently, the guest materials used in blue organic light-emitting diodes (OLEDs) are traditional fluorescent materials. Due to transition prohibition, traditional fluorescent materials can only utilize 25% of singlet excitons for emission, leaving 75% of triplet excitons unusable. This results in a theoretical maximum internal quantum efficiency of only 25% for traditional fluorescent devices. In contrast, blue phosphorescent devices, due to the introduction of heavy metals, can achieve triplet exciton emission, with a theoretical maximum internal quantum efficiency reaching 100%, thus solving the problem of excessively low internal quantum efficiency. Therefore, the development of blue phosphorescent OLEDs is of paramount importance.

[0046] A typical organic light-emitting diode (OLED) device comprises an anode, a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), an emissive layer (EML), a hole blocking layer (HBL), an electron transport layer (ETL), an electron injection layer (EIL), and a cathode, deposited sequentially on a substrate. When an OLED device operates, a voltage is applied between the cathode and the anode. Electrons and holes are injected from the cathode and anode, respectively, pass through several intermediate layers, and are then injected into and transported within the emissive layer. They recombine in the emissive layer to form excitons, which emit photons, thus enabling the device to emit light. Therefore, the choice of the emissive layer directly affects the efficiency of carrier recombination to form excitons, thereby influencing the device's performance. The emissive layer needs to possess both good electron injection and hole injection transport properties.

[0047] In traditional blue phosphorescent devices, the emitting layer is a single layer, making it difficult to balance the injection and transport of electrons and holes. When the host's hole injection and transport performance is stronger, the exciton recombination center is closer to the EML / HBL interface; when the host's electron injection and transport performance is stronger, the exciton recombination center is closer to the EBL / EML interface, resulting in exciton accumulation at the interface. Blue phosphorescent guest materials have long triplet exciton lifetimes and high exciton energies. Excitons accumulate in large quantities at the EML / HBL or EBL / EML interface, easily leading to non-radiative transitions such as TTA and TPQ. Furthermore, high exciton energy accumulation can cause material stability issues, such as breakage at low bond energies, thus affecting the device's efficiency and lifespan.

[0048] In a first aspect, this disclosure provides a light-emitting device, comprising:

[0049] A first carrier layer, a light-emitting layer, and a second carrier layer are stacked together. The light-emitting layer includes a first light-emitting layer, a second light-emitting layer, and a third light-emitting layer stacked together. The first light-emitting layer is disposed close to the first carrier layer. The carrier transport rates of the first light-emitting layer and the third light-emitting layer are different.

[0050] According to some embodiments of this disclosure, the hole transport rate of the first light-emitting layer is greater than the hole transport rate of the third light-emitting layer, and the electron transport rate of the first light-emitting layer is less than the electron transport rate of the third light-emitting layer.

[0051] According to some embodiments of this disclosure, the first light-emitting layer includes a first host material and a first object material, the second light-emitting layer includes a first host material, a second host material and a second object material, and the third light-emitting layer includes a second host material and a third object material, wherein the first host material and the second host material are different.

[0052] To address the challenge of balancing electron and hole injection and transport in single-layer blue phosphorescent devices, this disclosure provides a three-layer emissive-emitting device. The amount of bulk material in the second emissive-emitting layer differs from that in the first and third emissive-emitting layers. The first emissive-emitting layer, closer to the anode, exhibits excellent hole injection and transport capabilities, while the third emissive-emitting layer, closer to the cathode, provides excellent electron injection and transport capabilities. The middle second emissive-emitting layer simultaneously possesses good hole and electron transport capabilities. This allows for better injection of electrons and holes into the emissive layers. Furthermore, by adjusting the proportions and energy levels of the bulk materials in each of the three emissive-emitting layers, carrier distribution can be better balanced. Simultaneously, the exciton recombination region can be broadened, and this recombination region is concentrated more within the emissive layers, reducing the large exciton accumulation at the EML / HBL or EBL / EML interface. This reduces energy loss during non-radiative transitions, improving device efficiency and stability.

[0053] According to some embodiments of this disclosure, the first light-emitting layer includes a first host material, a second host material, a third host material, and a first guest material; the second light-emitting layer includes a first host material, a second host material, and a second guest material; and the third light-emitting layer includes a first host material, a second host material, a fourth host material, and a third guest material. The first host material, the second host material, the third host material, and the fourth host material are different. This arrangement in this disclosure aims to ensure good hole transport performance in the first light-emitting layer, good electron transport performance in the third light-emitting layer, and good hole and electron transport performance in the second light-emitting layer, while minimizing the types of materials used and reducing the amount of crucible and vapor deposition chamber used in actual production.

[0054] According to some embodiments of this disclosure, in the first light-emitting layer, the second light-emitting layer and the third light-emitting layer, at least one of the host materials in each layer contains a carbazole group.

[0055] Because blue phosphorescent guest materials have high triplet exciton energies and long lifetimes, more stringent conditions are imposed on their host materials. First, suitable HOMO and LUMO energy levels are required to ensure good carrier injection into the emitting layer. Generally, BH-P has a suitable HOMO to ensure hole injection, and BH-N has a suitable LUMO to ensure electron injection. When the two host materials RH-N and RH-P form an excitocomplex, a suitable difference between the HOMO of RH-P and the LUMO of RH-N must also be ensured. Second, the host materials also need to have high and well-matched hole and electron mobility to balance the carrier distribution in the emitting layer. Generally, BH-P has a high hole mobility, and BH-N has a high electron mobility to improve carrier recombination efficiency and exciton utilization. Furthermore, the host material must possess suitable S1 and T1 energy levels. The S1 energy level of the host material must be higher than that of the guest material, and the T1 energy level of the host material must also be higher than that of the guest material. This is because phosphorescent guest materials utilize T1-state excitons for luminescence. When the two host materials RH-N and RH-P form an exciton complex, the T1 energy level of the resulting exciton complex must be greater than that of the guest material. Simultaneously, because OLED devices generate Joule heating when operating under applied voltage, and BD has high exciton energy, the host material also needs to possess good thermal stability to ensure the stability and long lifespan of the OLED device.

[0056] In short, excellent blue light source materials should possess the following characteristics:

[0057] 1. Suitable HOMO and LUMO energy levels, specifically: BH-P has a suitable HOMO, and BH-N has a suitable LUMO;

[0058] 2. Higher and better matched hole and electron mobility, specifically: BH-P has higher hole mobility, and BH-N has higher electron mobility;

[0059] 3. Suitable S1 and T1 energy levels, specifically: S1 and T1 energy levels higher than BD;

[0060] 4. Good stability. Specifically, the material has high bond energy and a certain degree of rigidity.

[0061] Therefore, in view of the above situation, the host material used in this disclosure has a substituted carbazole structure. The carbazole fragment has a high T1 energy level and good stability, making it suitable for use as a host material for blue phosphorescence with high triplet exciton energy. At the same time, the strong electron-donating property of carbazole makes it suitable for use as a P-type blue light host. When it is combined with a strong electron-withdrawing group, it can improve the LUMO energy level of the material and is also suitable for N-type blue light hosts.

[0062] According to some embodiments of this disclosure, the first main material includes: a compound having chemical formula I, the structure of which is:

[0063] A11 is selected from one of chemical formulas 1, 2, and 3:

[0064] Wherein, * represents the connection site between A11 and chemical formula I, and R111-R119 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C3 0 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic group, -LN-(Ar1)(Ar2) or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings; n111, n112 and n119 are integers from 0 to 4, n113-118 are integers from 0 to 5, and when n111-n119 are integers greater than 1, each R111-R119 may be the same or different;

[0065] L11 is independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0066] R11-R18 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic, -LN-(Ar1)(Ar2), or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings;

[0067] Ar1 and Ar2 are each independently selected from hydrogen, deuterium, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic group, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring.

[0068] According to some embodiments of this disclosure, the first body material includes, but is not limited to, the following structures:

[0069] According to some embodiments of this disclosure, the second body material includes:

[0070] Compounds having chemical formula II have the following structure:

[0071] Wherein, Har is a substituted or unsubstituted 3-30 member heteroaryl group;

[0072] L12 is independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0073] R21-R28 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic, -LN-(Ar1)(Ar2), or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings;

[0074] Har is selected from one of the chemical formulas 4, 5, 6 and 7;

[0075] Wherein, * represents the connection site between Har and chemical formula II; X21-X39 are each independently selected from CR2 or N, and at least one of X21-X23 is N, at least one of X24-X31 is N, and at least one of X32-X39 is N; Y is independently selected from NR44, CR45R46, O, S, or Se; Ar21 and Ar22 each independently represent hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3- C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring; L independently represents a single bond, substituted or unsubstituted C1-C30 alkylene, substituted or unsubstituted C6-C30 arylene, substituted or unsubstituted 5-30-membered heteroarylene, or substituted or unsubstituted C3-C30 cycloalkylene;

[0076] R2 and R29 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic, -LN-(Ar1)(Ar2), or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings; n29 is an integer from 0 to 7, and when n29 is an integer greater than 1, each R29 is the same or different;

[0077] Ar1 and Ar2 are each independently selected from hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic group, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring;

[0078] L is independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0079] According to some embodiments of this disclosure, the second body material includes, but is not limited to, the following structures:

[0080] According to some embodiments of this disclosure, the third body material includes:

[0081] Compounds having chemical formula III have the following structure:

[0082] Among them, L31-L33 are each independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0083] Ar31-Ar33 are each independently selected from hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic group, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring.

[0084] According to some embodiments of this disclosure, the third body material includes, but is not limited to, the following structures:

[0085] According to some embodiments of this disclosure, the fourth body material includes:

[0086] Compounds having chemical formula IV have the following structure:

[0087] R41-R43 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C2-C30 alkynyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclic, -LN-(Ar1)(Ar2), or bonded to adjacent substituents to form substituted or unsubstituted 3-30 membered rings;

[0088] n41-n43 are integers from 0 to 5, and when n41-n43 are integers greater than 1, each R41-R43 is either the same or different;

[0089] Ar1 and Ar2 each independently represent hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 5-30-membered heteroaryl, substituted or unsubstituted 3-30-membered heterocyclic group, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30-membered ring;

[0090] L is independently selected from single bonds, substituted or unsubstituted C1-C30 alkylene groups, substituted or unsubstituted C6-C30 arylene groups, substituted or unsubstituted 5-30 heteroarylene groups, or substituted or unsubstituted C3-C30 cycloalkylene groups.

[0091] According to some embodiments of this disclosure, the fourth body material includes, but is not limited to, the following structures:

[0092] Furthermore, some energy level parameters and mobility parameters of the compound disclosed herein were simulated and measured. Gaussian simulations were performed on the S1, T1, HOMO, and LUMO parameters of the compound. The simulation units and functionals used were 6-31g** and b3lyp. The mobility was calculated using the SCLC method. The energy level and mobility data are shown in Table 1. The data in the table show that the compound disclosed herein possesses suitable S1, T1, HOMO, and LUMO energy levels to serve as a blue light host.

[0093] Table 1

[0094] According to some embodiments of this disclosure, the hole transport region may include one or more of a hole injection layer, a hole transport layer, and an electron blocking layer; the electron transport region may include one or more of a hole blocking layer, an electron transport layer, and an electron injection layer; the light extraction region may include one or more light extraction layers; the charge generation region may include one or more of a P-type charge generation layer (P-CGL), an N-type charge generation layer (NCGL), and other organic layers; and the light emission region may include one or more light emission layers.

[0095] According to some embodiments of this disclosure, in the device structure, the anode can be a transparent oxide ITO, IZO, or a composite electrode formed of ITO / Ag / ITO, Ag / IZO, CNT / ITO, CNT / IZO, etc.; the cathode can be a silver-magnesium composite electrode or an Al electrode. The electroluminescent device also includes a substrate disposed on the side of the anode away from the cathode. The substrate can be a transparent rigid or flexible material, such as glass, polyimide, etc., enabling both rigid substrate displays and flexible displays.

[0096] According to some embodiments of this disclosure, the hole injection layer can be an inorganic oxide, such as oxides of metals such as molybdenum, titanium, vanadium, rhenium, ruthenium, chromium, zirconium, hafnium, tantalum, silver, tungsten, and manganese, or it can be a dopant of a strong electron-withdrawing system, such as F4TCNQ, HAT-CN, etc., or it can be P-type doped in the hole transport material. The thickness of the hole injection layer can be 3nm to 30nm.

[0097] According to some embodiments of this disclosure, the hole transport layer is made of a material with good hole transport characteristics, such as aromatic amine or carbazole materials, such as NPB, TPD, BAFLP, DFLDPBi, etc., and the thickness of the hole transport layer can be 30nm to 300nm.

[0098] According to some embodiments of this disclosure, the electron blocking layer, i.e. the light-emitting auxiliary layer, has hole transport characteristics. The material of the light-emitting auxiliary layer can be an aromatic amine or carbazole material, such as TCTA, CBP, PCzPA, etc., and the thickness of the electron blocking layer can be 2nm to 150nm.

[0099] According to some embodiments of this disclosure, the hole blocking layer includes aromatic heterocyclic compounds, such as imidazole derivatives, imidazopyridine derivatives, benzimidazole-phenanthridine derivatives, and pyrimidine derivatives, triazine derivatives, and other aziridine derivatives, as well as compounds containing a nitrogen-containing six-membered ring structure, such as quinoline derivatives, isoquinoline derivatives, and phenanthreneroline derivatives. It may also include compounds with phosphine oxide substituents on the heterocycle, such as TPBi, BCP, OXD-7, TAZ, p-EtTAZ, BPhen, etc. The thickness of the hole blocking layer can be 3 nm to 100 nm.

[0100] According to some embodiments of this disclosure, the electron transport layer also includes aromatic heterocyclic compounds, such as imidazole derivatives, imidazopyridine derivatives, benzimidazole-phenanthridine derivatives, and pyrimidine derivatives, triazine derivatives, and other aziridine derivatives, as well as compounds containing a nitrogen-containing six-membered ring structure, such as quinoline derivatives, isoquinoline derivatives, and phenanthreneroline derivatives. It may also include compounds with phosphine oxide substituents on the heterocycle, such as TPBi, BCP, OXD-7, TAZ, p-EtTAZ, BPhen, etc. At the same time, the electron transport layer may also contain another doping material, such as Liq, Yb, etc., to enhance electron injection and transport characteristics. The thickness of the electron transport layer can be 20 nm to 150 nm.

[0101] According to some embodiments of this disclosure, the electron injection layer material includes alkali metals or metals, such as LiF, Yb, Mg, Ca or their compounds, and the thickness of the electron injection layer can be 1 nm to 15 nm.

[0102] According to some embodiments of this disclosure, the light extraction region may include one or more light extraction layers, and the light extraction layer material may include various organic materials, inorganic materials, or a combination of organic and inorganic materials.

[0103] According to some embodiments of this disclosure, in addition to the blue light emitted by the three light-emitting layers, the emission colors of the other light-emitting regions can be various colors such as red, green, blue, yellow, orange, and white. The light-emitting object can include any one of conventional fluorescent light-emitting materials, phosphorescent light-emitting materials, and thermally activated delayed fluorescence materials. The host material of the light-emitting layer can contain one material, or two or more materials, and may also contain compounds disclosed herein. The thickness of a single light-emitting region can be 10 nm to 80 nm.

[0104] According to some embodiments of this disclosure, the first charge carrier layer includes a first hole transport layer, the second charge carrier layer includes a first electron transport layer, and further includes: a first light-emitting region, the first light-emitting region being disposed on the side of the first electron transport layer away from the light-emitting layer; the first light-emitting region includes: a charge generation layer, a second hole transport layer, a fourth light-emitting layer, and a second electron transport layer stacked together, the charge generation layer being disposed close to the first electron transport layer.

[0105] According to some embodiments of this disclosure, the first charge carrier layer includes a first hole transport layer, the second charge carrier layer includes a first electron transport layer, and further includes a second light-emitting region disposed on the side of the first hole transport layer away from the light-emitting layer; the second light-emitting region includes a third hole transport layer, a fifth light-emitting layer, a third electron transport layer, and a charge generation layer stacked together, the charge generation layer being disposed close to the first hole transport layer.

[0106] Optionally, the organic electroluminescent device provided in this disclosure has the structure shown in FIG1. ​​Specifically, the layers in the device structure are represented as follows: 0 is the substrate; 1 is the anode; 2 is the first hole transport layer; 3-1 is the first light-emitting layer; 3-2 is the second light-emitting layer; 3-3 is the third light-emitting layer; 4 is the first electron transport layer; 5 is the cathode; and 6 is the light extraction region.

[0107] Optionally, the organic electroluminescent device provided in this disclosure has the structure shown in Figure 2 or Figure 3. Specifically, the layers in the device structure are represented as follows: 0 is the substrate; 1 is the anode; 2 is the first hole transport layer; 3-1 is the first light-emitting layer; 3-2 is the second light-emitting layer; 3-3 is the third light-emitting layer; 4 is the first electron transport layer; 5 is the cathode; 6 is the light extraction region; 7 is the charge generation region; 8 is the second hole transport layer; 9 is the fourth light-emitting layer; 10 is the second electron transport layer; 11 is the fifth light-emitting layer; 12 is the third hole transport layer; and 13 is the third electron transport layer. Compared with the structure in Figure 1, the structures in Figures 2 and 3 have an additional light-emitting region, which greatly improves the device lifetime.

[0108] Secondly, this disclosure provides a display panel that includes the light-emitting devices described above.

[0109] Thirdly, this disclosure provides a display device, which includes a display panel as described above.

[0110] Example 1

[0111] The pre-prepared ITO substrate was cleaned and dried.

[0112] HIL, HTL, and EBL (B-Prime) were sequentially deposited onto the anode.

[0113] Then, the material for the luminescent region is deposited by vapor deposition;

[0114] Then, HBL, ETL, EIL(Yb), cathode and photoextraction layer (CPL) are deposited sequentially.

[0115] The light-emitting region consists of three layers: a first light-emitting layer, a second light-emitting layer, and a third light-emitting layer, which are deposited sequentially. The first light-emitting layer contains compound I-9 and BD in a mass ratio of 95:5; the second light-emitting layer contains compound I-9, compound II-3, and BD in a mass ratio of 47:47:6; and the third light-emitting layer contains compound II-3 and BD in a mass ratio of 95:5.

[0116] The device structure is as follows: HIL (5nm) / HTL (100nm) / EBL (5nm) / Ⅰ-9:BD (95:5,5nm) / Ⅰ-9:Ⅱ-3:BD (47:47:6,15nm) / Ⅱ-3:BD (95:5,5nm) / HBL (5nm) / ETL:LiQ (1:1,30nm) / Yb (1nm) / Mg:Ag (1:9,15nm) / CPL (60nm).

[0117] The specific chemical structural formulas of the above substances are shown below:

[0118] Example 2

[0119] In Example 1, all compounds I-9 were replaced with compound I-15, and all compounds II-3 were replaced with compound II-8. The other steps were the same, and the organic light-emitting device 2 of this example was obtained.

[0120] Examples 3 to 8

[0121] The light-emitting areas of Examples 3 to 8 are the same as those of Examples 1-2, consisting of three light-emitting layers. The specific materials and proportions of each layer are shown in Table 2.

[0122] Comparative Example 1

[0123] Comparative Example 1 has only one luminescent layer in its luminescent region, which contains compound I-9, compound II-3 and BD in a mass ratio of 47:47:5 and has a thickness of 25 nm. The other layers are the same as in Example 1. The specific materials and ratios of each layer are shown in Table 2.

[0124] Table 2

[0125] Example 9

[0126] The pre-prepared ITO substrate was cleaned and dried.

[0127] HIL, HTL, and EBL (B-Prime) were sequentially deposited onto the anode; then the first luminescent region material was deposited.

[0128] Then HBL, ETL, n-CGL, p-CGL, HTL, and EBL are deposited sequentially by vapor deposition;

[0129] Then, the material for the second luminescent region is deposited by vapor deposition;

[0130] Then, HBL, ETL, EIL(Yb), cathode, and light extraction layer (CPL) are deposited sequentially. The first luminescent region consists of three layers deposited sequentially: a first luminescent layer, a second luminescent layer, and a third luminescent layer. The first luminescent layer contains compound I-9 and BD in a mass ratio of 95:5; the second luminescent layer contains compound I-9, compound II-3, and BD in a mass ratio of 47:47:6; and the third luminescent layer contains compound II-3 and BD in a mass ratio of 95:5. The second luminescent region has only one luminescent layer containing compound I-9, compound II-3, and BD in a mass ratio of 47:47:6.

[0131] The device structure is as follows: HIL (5nm) / HTL (100nm) / EBL (5nm) / Ⅰ-9:BD (95:5,5nm) / Ⅰ-9:Ⅱ-3:BD (47:47:6,15nm) / Ⅱ-3:BD (95:5,5nm) / HBL (5nm) / ETL:LiQ (1:1,15nm) / n-CGL (18nm) / n-CGL (15nm) / HTL (20nm) / EBL (5nm) / Ⅰ-9:Ⅱ-3:BD (47:47:6,25nm) / HBL (5nm) / ETL:LiQ (1:1,30nm) / Yb (1nm) / Mg:Ag (1:9,15nm) / CPL (60nm).

[0132] Examples 10 to 15

[0133] The preparation methods of Examples 10 to 15 are the same as those of Example 9, except that the setting of the light-emitting region is different from that of Example 9. The specific materials and proportions of each layer of the light-emitting region are shown in Table 3.

[0134] Comparative Example 2

[0135] The first luminescent region of Comparative Example 2 has only one luminescent layer, containing compound I-9, compound II-3 and BH in a mass ratio of 47:47:6, with a thickness of 25 nm; the second luminescent region also has only one luminescent layer, containing compound I-9, compound II-3 and BH in a mass ratio of 47:47:6, with a thickness of 25 nm; the remaining layers are the same as in Example 9, and the specific materials and proportions of each layer are shown in Table 3.

[0136] Table 3

[0137] Test case

[0138] Voltage and efficiency Cd: Operating voltage, voltage, and efficiency were all obtained using PR680 IVL testing;

[0139] Lifespan: This refers to the service life of device M6000, with a fixed brightness level such as J = 15mA / cm. 2 The light remains on, decreasing from 100% brightness to 95% brightness (LT95%).

[0140] The test results are recorded in Tables 2 and 3, respectively. It should be noted that Table 2 uses the data from Comparative Example 1 as a reference, and sets its voltage, efficiency, and lifespan data to 100%. Table 3 uses the data from Comparative Example 2 as a reference, and sets its voltage, efficiency, and lifespan data to 100%.

[0141] As shown in Table 2, the three-layer light-emitting device of this embodiment exhibits lower voltage, higher efficiency, and longer lifetime compared to the single-layer light-emitting device of Comparative Example 1. As shown in Table 3, among stacked devices, the three-layer light-emitting device of this embodiment exhibits lower voltage, higher efficiency, and longer lifetime compared to the single-layer light-emitting device in each light-emitting region of Comparative Example 2. In particular, Examples 11 and 15, which employ a three-layer light-emitting structure in both light-emitting regions, demonstrate even better device performance, exhibiting lower voltage, higher efficiency, and longer lifetime. This is because the three-layer light-emitting scheme of this design improves upon the difficulty of balancing electron and hole injection and transport in a single-layer light-emitting layer, reducing the problem of excessive exciton accumulation at the EML / HBL or EBL / EML interface, decreasing non-radiative transitions, reducing the impact of high-energy excitons on the HBL and EBL, improving device efficiency, and extending lifetime.

[0142] The embodiments of this disclosure have been described above with reference to the accompanying drawings. However, this disclosure is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this disclosure without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this disclosure.

Claims

1. A light emitting device, wherein, The application relates to an organic electroluminescence device, comprising: a first carrier layer, a light-emitting layer and a second carrier layer which are arranged in a stack, wherein the light-emitting layer comprises a first light-emitting layer, a second light-emitting layer and a third light-emitting layer which are arranged in a stack, and the first light-emitting layer is arranged close to the first carrier layer, and the first light-emitting layer and the third light-emitting layer have different carrier transport rates. The hole transport rate of the first light-emitting layer is greater than the hole transport rate of the third light-emitting layer, and the electron transport rate of the first light-emitting layer is less than the electron transport rate of the third light-emitting layer.

2. The light-emitting device according to claim 1, wherein The first light-emitting layer comprises a first host material and a first guest material, the second light-emitting layer comprises a first host material, a second host material and a second guest material, and the third light-emitting layer comprises a second host material and a third guest material, and the first host material is different from the second host material.

3. The light-emitting device according to claim 1, wherein The first light-emitting layer comprises a first host material, a second host material, a third host material and a first guest material, the second light-emitting layer comprises a first host material, a second host material and a second guest material, and the third light-emitting layer comprises a first host material, a second host material, a fourth host material and a third guest material, and the first host material, the second host material, the third host material and the fourth host material are different.

4. The light-emitting device according to claim 1, wherein At least one host material in each of the first light-emitting layer, the second light-emitting layer and the third light-emitting layer contains a carbazole group.

5. The light emitting device according to claim 3 or 4, wherein The first host material comprises:

6. The light-emitting device according to claim 3 or 4, wherein wherein * is a linking site of A11 and Formula I, R111-R119 are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, a substituted or unsubstituted C1-C30 alkyl, a substituted or unsubstituted C2-C30 alkenyl, a substituted or unsubstituted C2-C30 alkynyl, a substituted or unsubstituted C3-C30 cycloalkyl, a substituted or unsubstituted C1-C30 alkoxy, a substituted or unsubstituted C6-C30 aryl, a substituted or unsubstituted 5-30 membered heteroaryl, a substituted or unsubstituted 3-30 membered heterocyclyl, -L-N-(Ar1)(Ar2) or is bonded with an adjacent substituent to form a substituted or unsubstituted 3-30 membered ring; n111, n112 and n119 are integers from 0 to 4, n113-118 are integers from 0 to 5, and when n111-n119 are integers greater than 1, each R111-R119 is the same or different; Compounds of formula I, the structure of formula I is: wherein A11 is selected from one of Formula 1, Formula 2, and Formula 3: L11 is independently selected from a single bond, a substituted or unsubstituted C1-C30 alkylene, a substituted or unsubstituted C6-C30 arylene, a substituted or unsubstituted 5-30 membered heteroarylene, or a substituted or unsubstituted C3-C30 cycloalkylene; ​ R11-R18are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C2-C30alkynyl, substituted or unsubstituted C3-C30cycloalkyl, substituted or unsubstituted C1-C30alkoxy, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclyl, -L-N-(Ar1)(Ar2), or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30 membered ring; Ar1and Ar2are each independently selected from hydrogen, deuterium, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C3-C30cycloalkyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclyl, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30 membered ring.

7. The light-emitting device according to claim 3 or 4, wherein the second host material comprises: Compounds of formula II, the structure of which is: wherein Haris a substituted or unsubstituted 3-30 membered heteroaryl; L12is independently selected from a single bond, substituted or unsubstituted C1-C30alkylene, substituted or unsubstituted C6-C30arylene, substituted or unsubstituted 5-30 membered heteroarylene, or substituted or unsubstituted C3-C30cycloalkylene; R21-R28are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C2-C30alkynyl, substituted or unsubstituted C3-C30cycloalkyl, substituted or unsubstituted C1-C30alkoxy, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclyl, -L-N-(Ar1)(Ar2), or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30 membered ring; Har is selected from one of Formula 4, Formula 5, Formula 6, and Formula 7; wherein * is the linking site of Har and Formula II, X21-X39 are each independently selected from CR2or N, and at least one of X21-X23is N, at least one of X24-X31is N, and at least one of X32-X39is N; Y is independently selected from NR44, CR45R46, O, S, or Se; Ar21and Ar22are each independently hydrogen, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C3-C30cycloalkyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclyl, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30 membered ring; and L is independently a single bond, substituted or unsubstituted C1-C30alkylene, substituted or unsubstituted C6-C30arylene, substituted or unsubstituted 5-30 membered heteroarylene, or substituted or unsubstituted C3-C30cycloalkylene; R2and R29are each independently selected from hydrogen, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C2-C30alkynyl, substituted or unsubstituted C3-C30cycloalkyl, substituted or unsubstituted C1-C30alkoxy, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclyl, -L-N-(Ar1)(Ar2), or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30 membered ring; n29is an integer from 0 to 7, and when n29is an integer greater than 1, each R29is the same or different; Ar1and Ar2are each independently selected from hydrogen, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C3-C30cycloalkyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclyl, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30 membered ring; L is independently selected from a single bond, substituted or unsubstituted C1-C30alkylene, substituted or unsubstituted C6-C30arylene, substituted or unsubstituted 5-30 membered heteroarylene, or substituted or unsubstituted C3-C30cycloalkylene.

8. The light-emitting device according to claim 4, wherein The third host material comprises: The compound of formula III, the structure of which is: wherein L31-L33are each independently selected from a single bond, substituted or unsubstituted C1-C30alkylene, substituted or unsubstituted C6-C30arylene, substituted or unsubstituted 5-30 membered heteroarylene, or substituted or unsubstituted C3-C30cycloalkylene; wherein * is the linking site of Har and Formula II, X21-X39 are each independently selected from CR2or N, and at least one of X21-X23is N, at least one of X24-X31is N, and at least one of X32-X39is N; Y is independently selected from NR44, CR45R46, O, S, or Se; Ar21and Ar22are each independently hydrogen, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C3-C30cycloalkyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted 5-30 membered heteroaryl, substituted or unsubstituted 3-30 membered heterocyclyl, or bonded to an adjacent substituent to form a substituted or unsubstituted 3-30 membered ring; and L is independently a single bond, substituted or unsubstituted C1-C30alkylene, substituted or unsubstituted C6-C30arylene, substituted or unsubstituted 5-30 membered heteroarylene, or substituted or unsubstituted C3-C30cycloalkylene; Ar31-Ar33are each independently selected from hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C2-C30 alkenyl group, a substituted or unsubstituted C3-C30 cycloalkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted 5- to 30-membered heteroaryl group, a substituted or unsubstituted 3- to 30-membered heterocyclyl group, or are bonded to an adjacent substituent to form a substituted or unsubstituted 3- to 30-membered ring.

9. The light-emitting device according to claim 4, wherein The fourth host material includes: The compound of formula IV, the structure of which is: wherein R41-R43are each independently selected from hydrogen, a halogen, a cyano group, a nitro group, a hydroxyl group, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C2-C30 alkenyl group, a substituted or unsubstituted C2-C30 alkynyl group, a substituted or unsubstituted C3-C30 cycloalkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted 5- to 30-membered heteroaryl group, a substituted or unsubstituted 3- to 30-membered heterocyclyl group, -L-N-(Ar1)(Ar2), or are bonded to an adjacent substituent to form a substituted or unsubstituted 3- to 30-membered ring; n41-n43are integers from 0 to 5, and when n41-n43are integers greater than 1, each R41-R43are the same or different; Ar1and Ar2are each independently represent hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C2-C30 alkenyl group, a substituted or unsubstituted C3-C30 cycloalkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted 5- to 30-membered heteroaryl group, a substituted or unsubstituted 3- to 30-membered heterocyclyl group, or are bonded to an adjacent substituent to form a substituted or unsubstituted 3- to 30-membered ring; L is independently selected from a single bond, a substituted or unsubstituted C1-C30 alkylene group, a substituted or unsubstituted C6-C30 arylene group, a substituted or unsubstituted 5- to 30-membered heteroarylene group, or a substituted or unsubstituted C3-C30 cycloalkylene group.

10. The light-emitting device according to claim 1, wherein The first carrier layer includes a first hole transport layer, and the second carrier layer includes a first electron transport layer, and the light-emitting device further includes: a first light-emitting region disposed on a side of the first electron transport layer distal to the light-emitting layer; The first light-emitting region includes a charge generation layer, a second hole transport layer, a fourth light-emitting layer, and a second electron transport layer disposed in a stack, the charge generation layer disposed proximate to the first electron transport layer.

11. The light-emitting device according to claim 1, wherein The first carrier layer includes a first hole transport layer, and the second carrier layer includes a first electron transport layer, and the light-emitting device further includes: a second light-emitting region disposed on a side of the first hole transport layer distal to the light-emitting layer; The second light-emitting region includes a third hole transport layer, a fifth light-emitting layer, a third electron transport layer, and a charge generation layer disposed in a stack, the charge generation layer disposed proximate to the first hole transport layer.

12. A display panel, wherein, The light-emitting device of any one of claims 1-11.

13. A display device, wherein, Comprising the display panel described in claim 12.

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