Photoelectric device, preparation method thereof and display device

Abstract

The invention discloses a photoelectric device and a preparation method thereof and a display device, the photoelectric device comprises an anode, an active layer and a cathode which are stacked, and the material of the active layer comprises a self-assembly material. According to the photoelectric device provided by the technical scheme of the invention, the active layer containing the self-assembly material is adopted, so that the current efficiency of the device can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor devices, and particularly to an optoelectronic device, a preparation method thereof, and a display device. Background Art

[0002] Optoelectronic devices emit light by the recombination of electrons and holes, and are widely used in technical fields such as display and lighting. The lifetime and stability of optoelectronic devices are important parameters for evaluating device performance. At present, with the increasing requirements of users for product quality, improving device stability has become an urgent problem to be solved. Summary of the Invention

[0003] In view of this, the present application provides an optoelectronic device, a preparation method thereof, and a display device.

[0004] The embodiments of the present application are implemented as follows:

[0005] In a first aspect, an embodiment of the present application provides an optoelectronic device, which includes a stacked anode, an active layer, and a cathode. The material of the active layer includes a self-assembled material, and the self-assembled material includes one or more of a first compound and a second compound. Among them, the first compound has the structure shown in formula (1), and the second compound has the structure shown in formula (2):

[0006] (1)

[0007] (2)

[0008] Among them, M1 is selected from substituted or unsubstituted C1-C30 alkyl;

[0009] M2 is selected from any one of substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted aryl with 6-40 ring atoms, and substituted or unsubstituted heteroaryl with 6-40 ring atoms;

[0010] X1, X2, and X3 are each independently selected from one or more combinations of hydrogen, C1-C30 alkyl, and halogen groups;

[0011] Y1 and Y2 are each independently selected from one or more combinations of hydrogen, hydroxyl, and C1-C30 alkoxy, and at least one of Y1 and Y2 is selected from C1-C30 alkoxy or hydroxyl;

[0012] When being substituted by a substituent, the substituent is independently selected from one or more combinations of D, C1-C10 alkyl, C1-C10 alkoxy, C2-C10 alkoxycarbonyl, C2-C10 alkylcarbonyl, C6-C10 aryl, cyano, nitro, mercapto, hydroxyl, carboxyl, amino, and halogen groups each time it appears.

[0013] In a second aspect, an embodiment of the present application provides a method for manufacturing an optoelectronic device, including the following steps:

[0014] Providing a prefabricated device, where the prefabricated device includes a bottom electrode;

[0015] Preparing an active layer on one side of the bottom electrode;

[0016] Preparing a top electrode on the side of the active layer facing away from the prefabricated device to obtain an optoelectronic device;

[0017] Wherein, the bottom electrode is selected from one of an anode and a cathode, and the top electrode is selected from the other of the anode and the cathode;

[0018] The preparation of the active layer includes: depositing the material of the active layer to obtain the active layer, where the material of the active layer includes a self-assembled material, and the self-assembled material includes one or more of a first compound and a second compound. Among them, the first compound has the structure shown in formula (1), and the second compound has the structure shown in formula (2):

[0019] (1)

[0020] (2)

[0021] Wherein, M1 is selected from a substituted or unsubstituted C1-C30 alkyl group;

[0022] M2 is selected from any one of a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted aryl group with 6-40 ring atoms, and a substituted or unsubstituted heteroaryl group with 6-40 ring atoms;

[0023] X1, X2, and X3 are each independently selected from one or more combinations of hydrogen, a C1-C30 alkyl group, and a halogen group;

[0024] Y1 and Y2 are each independently selected from one or more combinations of hydrogen, a hydroxyl group, and a C1-C30 alkoxy group, and at least one of Y1 and Y2 is selected from a C1-C30 alkoxy group or a hydroxyl group;

[0025] When being substituted by a substituent, the substituent is independently selected from one or more combinations of D, a C1-C10 alkyl group, a C1-C10 alkoxy group, a C2-C10 alkoxycarbonyl group, a C2-C10 alkylcarbonyl group, a C6-C10 aryl group, a cyano group, a nitro group, a mercapto group, a hydroxyl group, a carboxyl group, an amino group, and a halogen group each time it appears.

[0026] In a third aspect, the present application proposes a display device, including the optoelectronic device described above, or including an optoelectronic device manufactured by the manufacturing method described above.

[0027] The optoelectronic device provided by the technical solution of this application uses an active layer containing self-assembled materials, which helps to improve the lifespan and stability of the device. Description of the Drawings

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of this application. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] Figure 1 It is a schematic structural diagram of an optoelectronic device provided by an embodiment of this application;

[0030] Figure 2 It is a schematic flowchart of a preparation method of an optoelectronic device provided by an embodiment of this application;

[0031] Reference Signs: Optoelectronic Device 100; Anode 10; Cathode 20; Active Layer 30; First Interface Layer 31; Light-Emitting Layer 32; Electron Function Layer 33; Second Interface Layer 34. Detailed Embodiments

[0032] The following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the drawings in the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, rather than all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope protected by this application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain this application, and are not used to limit this application. In this application, unless otherwise stated, the orientation terms such as "upper" and "lower" specifically refer to the drawing directions in the drawings. Additionally, in the description of this application, the term "including" means "including but not limited to". The various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be construed as a rigid limitation on the scope of this application; therefore, it should be considered that the described range description has specifically disclosed all possible sub-ranges and individual values within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and individual numbers within that range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.

[0033] In this application, "and / or" describes the relationship between related objects and indicates that there can be three relationships. For example, A and / or B can represent: A exists alone, both A and B exist simultaneously, or B exists alone. Here, A and B can be singular or plural.

[0034] In this application, "at least one" means one or more, and "a plurality" means two or more. "At least one kind", "at least one of the following items (pieces)" or similar expressions refer to any combination of these items, including any combination of single items (pieces) or plural items (pieces). For example, "at least one of a, b, or c", or "at least one of a, b, and c" can both represent: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can each be single or multiple.

[0035] Term Explanation

[0036] In this application, "substituted or unsubstituted" means that the defined group can be substituted or not. When the defined group is substituted, it should be understood as optionally substituted by groups acceptable in the art, including but not limited to: one or more combinations of D, C1 - C10 alkyl, C1 - C10 alkoxy, C2 - C10 alkoxycarbonyl, C2 - C10 alkylcarbonyl, C6 - C10 aryl, cyano, nitro, mercapto, hydroxy, carboxy, amino, and halogen groups. In this application, "combination of multiple kinds" means the situation where at least one hydrogen in a group is substituted by other groups (it can be substituted by one other group or multiple other groups). For example, the combination of hydroxy, halogen, and amino can mean that at least two hydrogens in the amino group are respectively substituted by hydroxy and halogen.

[0037] In this application, when the same substituent appears multiple times, it can be independently selected from different groups. If the general formula contains multiple R1s, then R1s can be independently selected from different groups. For example 6 Rs on the benzene ring 1 can be the same as or different from each other.

[0038] In this application, "alkyl" can represent a straight-chain alkyl, a branched-chain alkyl, and / or a cyclic alkyl. The number of carbon atoms in the alkyl can be 1 - 30, 1 - 20, 1 - 10, or 1 - 6. Phrases containing this term, for example, "C 1-9"Alkyl" refers to an alkyl group containing 1 to 9 carbon atoms, and each occurrence can independently be a C1 alkyl group, C2 alkyl group, C3 alkyl group, C4 alkyl group, C5 alkyl group, C6 alkyl group, C7 alkyl group, C8 alkyl group, or C9 alkyl group. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-tert-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyl octyl, 2-hexyloctyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyl decyl, 2-butyl decyl, 2-hexyl decyl, 2-octyl decyl, n-undecyl, n-dodecyl, 2-ethyldodecyl, 2-butyl dodecyl, 2-hexyl dodecyl, 2-octyl dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, 2-ethylhexadecyl, 2-butyl hexadecyl, 2-hexyl hexadecyl, 2-octyl hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, 2-ethyl eicosyl, 2-butyl eicosyl, 2-hexyl eicosyl, 2-octyl eicosyl, n-heneicosyl, n-docosyl, n-tricosyl, n-tetracosyl, n-pentacosyl, n-hexacosyl, n-heptacosyl, n-octacosyl, n-nonacosyl, n-triacontyl, etc. Thioalkyl refers to a group in which at least one hydrogen in the alkyl group is replaced by a sulfur atom.

[0039] In this application, "-C n H 2n+1 ", without special annotation or limitation, represents a straight-chain alkyl group. For example, -C6H 13 represents n-hexyl, -C 12 H 25 represents n-dodecyl.

[0040] In this application, "the number of ring atoms" represents the number of atoms that form the ring itself in a structural compound obtained by bonding atoms in a ring (for example, a monocyclic compound or a polycyclic compound). It can be understood that the ring atoms are not limited to carbon atoms. When a heterocycle is contained in a cyclic compound, the heteroatom is also an atom that forms the heterocycle and belongs to the ring atoms. When the ring is substituted by a substituent, the atoms contained in the substituent are not included in the ring-forming atoms. The same applies to "the number of ring atoms" described below without special explanation. For example, the number of ring atoms in a benzene ring is 6, the number of ring atoms in a naphthalene ring is 10, and the number of ring atoms in a thiophenyl group is 5.

[0041] In the present application, "aryl, aryl group or aromatic group" refers to a hydrocarbon group containing at least one aromatic ring, such as a monocyclic compound, a fused-ring compound or a polycyclic non-fused compound, etc. The ring atoms of the aryl group can be 6 to 40, 6 to 30, 6 to 20, or 6 to 10. "Heteroaryl or heteroaromatic group" refers to an aromatic hydrocarbon group containing at least one heteroatom, such as a monocyclic compound containing at least one heteroatom, a fused-ring compound containing at least one heteroatom or a polycyclic non-fused compound containing at least one heteroatom, etc. The heteroatom is preferably selected from Si, N, P, O, S and / or Ge, and particularly preferably selected from Si, N, P, O and / or S. Among them, the fused-ring compound or the fused compound has the same meaning and can be interchanged, specifically referring to a compound that can have two or more rings, where two ring atoms are shared by two adjacent rings, that is, a fused ring. For the purposes of the present application, the aromatic group or heteroaromatic group includes not only the system of the aromatic ring, but also a non-aromatic ring system. Therefore, for example, systems such as pyridine, thiophene, pyrrole, pyrazole, triazole, imidazole, oxazole, oxadiazole, thiazole, tetrazole, pyrazine, pyridazine, pyrimidine, triazine, carbene, etc. are also considered aromatic groups or heteroaromatic groups for the purposes of this invention. For the purposes of the present application, the fused-ring aromatic or fused heteroaromatic ring system includes not only the system of the aromatic group or heteroaromatic group, but also, in which multiple aromatic groups or heteroaromatic groups can also be interrupted by short non-aromatic units (<10% non-H atoms, preferably less than 5% non-H atoms, such as C, N or O atoms). Therefore, for example, systems such as 9,9'-spirobifluorene, 9,9-diarylfluorene, triarylamine, diaryl ether, etc. are also considered fused-ring aromatic ring systems for the purposes of this invention.

[0042] In a preferred embodiment, the aromatic group is selected from: benzene, naphthalene, anthracene, fluoranthene, phenanthrene, benzo[a]phenanthrene, dibenzo[a,h]anthracene, tetracene, pyrene, benzo[a]pyrene, acenaphthene, fluorene, and their derivatives; the heteroaromatic group is selected from triazine, pyridine, pyrimidine, imidazole, furan, thiophene, benzofuran, benzothiophene, indole, carbazole, pyrroloimidazole, pyrrolopyrrole, thiophenopyrrole, thiophenothiophene, furanopyrrole, furanofuran, thiophenofuran, benzoisoxazole, benzoisothiazole, benzimidazole, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthridine, perimidine, quinazolinone, dibenzothiophene, dibenzofuran, carbazole and their derivatives.

[0043] In the present application, amino represents -NR 1 R 2 wherein, R 1 R 2 each independently represents H or an alkyl group, that is, amino can refer to -NH2, can also be -NH(alkyl), or can also be -N(alkyl)(alkyl).

[0044] In this application, "halogen group" represents -Cl, -Br, -F or -I; hydroxyl group represents -OH; carboxyl group represents -COOH; nitro group represents -NO2; mercapto group represents -SH; cyano group represents alkoxy group represents -OR; alkoxycarbonyl group represents alkylcarbonyl group represents wherein, R represents a straight-chain alkyl group or a branched-chain alkyl group.

[0045] In this application, "its combination", "any combination thereof", "any combination mode thereof", etc. include all suitable combination modes of any two or more than two items in the listed items.

[0046] In a first aspect, an embodiment of this application provides an optoelectronic device 100, such as a quantum dot light-emitting diode (QLED), as Figure 1 shown, the optoelectronic device 100 includes an anode 10 and a cathode 20 which are oppositely arranged, and an active layer 30 disposed between the anode 10 and the cathode 20. The material of the active layer 30 includes a self-assembled material, and the self-assembled material includes one or more of a first compound and a second compound. Among them, the first compound has a structure shown in formula (1), and the second compound has a structure shown in formula (2):

[0047] (1)

[0048] (2)

[0049] wherein, M1 is selected from substituted or unsubstituted C1-C30 alkyl groups;

[0050] M2 is selected from any one of substituted or unsubstituted C1-C30 alkyl groups, substituted or unsubstituted aryl groups with 6 to 40 ring atoms, and substituted or unsubstituted heteroaryl groups with 6 to 40 ring atoms;

[0051] X1, X2, and X3 are each independently selected from one or more combinations of hydrogen, C1-C30 alkyl groups, and halogen groups;

[0052] Y1 and Y2 are each independently selected from one or more combinations of hydrogen, hydroxyl groups, and C1-C30 alkoxy groups, and at least one of Y1 and Y2 is selected from C1-C30 alkoxy groups or hydroxyl groups;

[0053] When being substituted by substituents, each occurrence of the substituent is independently selected from one or more combinations of D, C1-C10 alkyl groups, C1-C10 alkoxy groups, C2-C10 alkoxycarbonyl groups, C2-C10 alkylcarbonyl groups, C6-C10 aryl groups, cyano groups, nitro groups, mercapto groups, hydroxyl groups, carboxyl groups, amino groups, and halogen groups.

[0054] The hole mobility of the self-assembled material is greater than or equal to 10 -6 cm 2 / V / s, and the self-assembled material has a self-assembling group, such as a phosphonic acid group or a phosphonic acid ester group in the first compound, and a silyl group in the second compound.

[0055] The optoelectronic device 100 provided by the technical solution of the present application uses the active layer 30 containing the self-assembled material, which helps to improve the lifespan and stability of the device.

[0056] In some embodiments, M1 is selected from C1-C20 alkyl groups.

[0057] In some embodiments, X1, X2, and X3 are each independently selected from one or more combinations of C1-C30 alkyl groups and halogen groups.

[0058] In some embodiments, when Y1 and Y2 are each independently selected from one or more of hydrogen and C1-C30 alkoxy groups, M2 is selected from C1-C30 alkyl groups and aryl groups with 6 to 14 ring atoms; when Y1 and Y2 are each independently selected from hydroxyl groups, M2 is selected from the following structures:

[0059]

[0060] wherein, n is any integer from 1 to 10, and n1 and n2 are each independently selected from any integer from 1 to 4;

[0061] R 1 and R 2 are each independently selected from one or more combinations of halogen groups, substituted or unsubstituted C1-C30 alkoxy groups; when substituted by a substituent, the substituent is independently selected from one or more combinations of D, C1-C10 alkyl groups, C1-C10 alkoxy groups, C2-C10 alkoxy carbonyl groups, C2-C10 alkyl carbonyl groups, C6-C10 aryl groups, cyano groups, nitro groups, mercapto groups, hydroxyl groups, carboxyl groups, amino groups, and halogen groups each time it appears.

[0062] Since the self-assembled material has a self-assembling group, when the self-assembled material in the active layer 30 is distributed on the side in contact with the anode 10 of the film layer, the self-assembling group can be connected to the surface of the anode 10 to form a self-assembled film on the surface of the anode 10. According to the difference of the self-assembling group, there are various forms of the specific connection mode between the self-assembled material and the anode 10.

[0063] In some specific embodiments, the first compound includes one or more of the following compounds P1 to P2. Among them, compound P1 may be dimethyloctadecylchlorosilane, with a CAS number of 18643-08-8; compound P2 may be octadecyltrichlorosilane, with a CAS number of 112-04-9. When the self-assembled material in the active layer 30 is distributed on the side where the film layer contacts the anode 10, and the self-assembled material is selected from one or more of P1 to P2, the alkyl group in the compound structure can be connected to the metal atoms in the anode 10, which helps to form a self-assembled film on the surface of the anode 10.

[0064] In some specific embodiments, the second compound includes one or more of the following compounds P3 to P7. Among them, compound P3 may be ethyl phenylphosphonate, with a CAS number of 2511-09-3; compound P4 may be dimethyl phenylphosphonate, with a CAS number of 2240-41-7. When the self-assembled material in the active layer 30 is distributed on the side where the film layer contacts the anode 10, and the self-assembled material is selected from one or more of P3 to P4, the phosphate group in the compound structure can be connected to the metal atoms in the anode 10, which helps to form a self-assembled film on the surface of the anode 10; in addition, the phosphate group in the compound structure can also be bonded to the cationic defects on the surface of the quantum dot luminescent material in the form of a covalent bond, thereby playing a role in stabilizing the quantum dot luminescent material and helping to inhibit exciton quenching of the quantum dot luminescent material. Compound P5 may be (2-(9H-carbazol-9-yl)ethyl)phosphonic acid, also known as 2PACz, with a CAS number of 20999-38-6; compound P6 may be (2-(3,6-dibromo-9H-carbazol-9-yl)ethyl)phosphonic acid, also known as Br-2PACZ, with a CBNumber of CB59034502; compound P7 may be (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl)phosphonic acid, also known as MeO-2PACz, with a CAS number of 2377770-18-6. When the self-assembled material in the active layer 30 is distributed on the side where the film layer contacts the anode 10, and the self-assembled material is selected from one or more of P5 to P7, the hydroxyl group in the compound structure can be connected to the metal atoms in the anode 10, which helps to form a self-assembled film on the surface of the anode 10; in addition, the hydroxyl group in the compound structure can also be bonded to the cationic defects on the surface of the quantum dot luminescent material in the form of a covalent bond, thereby playing a role in stabilizing the quantum dot luminescent material and helping to inhibit exciton quenching of the quantum dot luminescent material.

[0065]

[0066] In some embodiments, the active layer 30 may include a first interface layer 31, which is connected to the surface of the anode 10 facing the cathode 20. The material of the first interface layer 31 includes a first material, which is selected from at least one of the self-assembled materials described above. The first interface layer 31 is formed by self-assembly of the first material on the surface of the anode 10 and is a self-assembled thin film with an ordered structure. The presence of the first interface layer 31 can modify the surface of the anode 10 facing the cathode 20, help improve its surface wettability, increase the work function of the anode 10, and promote hole injection. When the active layer 30 further includes a light-emitting layer 32, the presence of the first interface layer 31 can promote the energy level matching and interface contact effect between the anode 10 and the light-emitting layer 32, reduce the hole injection barrier, and further promote hole injection. In the process of fabricating a normal device, the design of the first interface layer 31 can also improve the film-forming quality of the light-emitting layer 32 and help improve the optoelectronic performance of the device.

[0067] Currently, the common optoelectronic device 100 is usually based on a "sandwich" structure, which consists of an anode 10, a hole functional layer, a light-emitting layer 32, and a cathode 20. Among them, the hole functional layer includes, but is not limited to, a hole injection layer, a hole transport layer, etc. Since the materials of the hole functional layer generally use p-type polymer materials, and these materials are complex to synthesize and have a high cost, it increases the fabrication difficulty and cost of the optoelectronic device 100 and limits the development of the optoelectronic device 100. In addition, for QLEDs, since most of these p-type polymer materials are characterized as hydrophobic, the interfacial contact between the hole functional layer and the quantum dot light-emitting layer 32 is poor, which also affects the performance of the device. The design of the first interface layer 31 can, to a certain extent, replace the hole functional layer and construct an optoelectronic device 100 without a hole transport layer. In this way, the traditional hole injection layer and hole transport layer are simplified, which helps reduce the raw material cost and fabrication cost of the device and improves the flexibility of device fabrication. At the same time, since the device structure without a hole transport layer does not contain hydrophilic hole injection layer materials such as PEDOT:PSS, the lifespan and long-term storage stability of the device are also significantly improved.

[0068] In some embodiments, the thickness of the first interface layer 31 is 1 to 5 nm, for example, it can be 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, and values between any two of the above values, etc. Controlling the thickness of the first interface layer 31 within this range can promote hole injection.

[0069] In some embodiments, the active layer 30 includes at least one of a light-emitting layer 32 and an electron functional layer 33. When the active layer 30 includes the light-emitting layer 32 and the electron functional layer 33, the electron functional layer 33 is located between the light-emitting layer 32 and the cathode 20.

[0070] In one embodiment, the material of the light-emitting layer 32 includes a quantum dot light-emitting material. In another embodiment, the material of the light-emitting layer 32 includes a quantum dot light-emitting material and a second material, and the second material is selected from at least one of the self-assembled materials described above.

[0071] In one embodiment, the material of the electron functional layer 33 includes an electron transport material. In another embodiment, the material of the electron functional layer 33 includes an electron transport material and a third material, and the third material is selected from at least one of the self-assembled materials described above.

[0072] It can be understood that the film layer structure of the optoelectronic device 100 is adjusted according to actual requirements. Based on this, there are various choices for the specific structure of the active layer 30. For example, in the first embodiment, the active layer 30 may be composed of a first interface layer 31 and an electron functional layer 33. Among them, the material of the electron functional layer 33 may be selected from an electron transport material or a mixture of an electron transport material and a third material; in the second embodiment, the active layer 30 may be composed of a first interface layer 31 and a light-emitting layer 32. Among them, the material of the light-emitting layer 32 may be selected from a quantum dot light-emitting material or a mixture of a quantum dot light-emitting material and a second material; in the third embodiment, the active layer 30 may be composed of a first interface layer 31, a light-emitting layer 32, and an electron functional layer 33. Similarly, in this embodiment, the material of the light-emitting layer 32 may be selected from a quantum dot light-emitting material or a mixture of a quantum dot light-emitting material and a second material, and the material of the electron functional layer 33 may be selected from an electron transport material or a mixture of an electron transport material and a third material.

[0073] It can be understood that the first material, the second material, and the third material may be the same or different.

[0074] Doping the self-assembled material in the light-emitting layer 32, the self-assembled material can passivate the light-emitting layer 32 rich in defects, thereby suppressing exciton quenching and improving the current efficiency and external quantum efficiency of the device. In addition, the self-assembled material aggregates on the side of the light-emitting layer 32 facing the anode 10, which also helps to reduce the hole injection from the anode 10 to the light-emitting layer 32 and improve the current density of the device.

[0075] Doping the self-assembled material in the electron functional layer 33 can block excessive electron injection and help to improve the balance of hole injection and electron injection in the device.

[0076] In some embodiments, the active layer 30 simultaneously includes a light-emitting layer 32 and an electron-functional layer 33. Self-assembled materials are doped in both the light-emitting layer 32 and the electron-functional layer 33. Under electrostatic interaction, the self-assembled materials in the electron transport layer tend to aggregate at the interface between the light-emitting layer 32 and the electron-functional layer 33, thereby forming a second interface layer 34 at the interface. That is, the active layer 30 includes a light-emitting layer 32, a second interface layer 34, and an electron-functional layer 33. The material of the second interface layer 34 is composed of at least part of a second material and at least a third material. The formation of the second interface layer 34 can better block the excessive electron injection from the electron-functional layer 33 and significantly improve the performance and stability of the device.

[0077] In some embodiments, the thickness of the second interface layer 34 is 1 to 5 nm, and can be, for example, 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, and values between any two of the above values, and so on.

[0078] In some embodiments, the active layer 30 is composed of a first interface layer 31, a light-emitting layer 32, a second interface layer 34, and an electron-functional layer 33. The material of the first interface layer 31 includes a first material. The material of the light-emitting layer 32 is selected from the mixture of a quantum dot light-emitting material and a second material, and the material of the electron-functional layer 33 is selected from the mixture of an electron transport material and a third material. In this embodiment, on the one hand, by setting the first interface layer 31 and doping self-assembled materials in the light-emitting layer 32, the interface contact, energy level matching, and injection barrier between the anode 10 and the light-emitting layer 32 are well improved, thereby significantly enhancing the hole injection, suppressing the interface exciton quenching, and increasing the current density. On the other hand, due to the electrostatic attraction of the self-assembled materials on the surfaces of the light-emitting layer 32 and the electron-functional layer 33, an ultra-thin second interface layer 34 is formed at the interface between the light-emitting layer 32 and the electron-functional layer 33, thereby significantly enhancing the hole injection of the device without a hole transport layer, suppressing the excessive electron injection from the electron-functional layer 33, and well improving the carrier balance. Overall, the brightness, current efficiency, lifetime, and stability of the device are significantly improved.

[0079] When the material of the light-emitting layer 32 includes the quantum dot light-emitting material and the second material, in the light-emitting layer 32, the ratio of the total mass of the quantum dot light-emitting material to the total mass of the second material is 20:(0.1 - 0.5); for example, it can be 20:0.1, 20:0.2, 20:0.3, 20:0.4, 20:0.5, and values between any two of the above values.

[0080] When the material of the electronic functional layer 33 includes the electron transport material and the third material, in the electronic functional layer 33, the mass ratio of the electron transport material to the third material is 20:(0.1 - 0.5); for example, it can be 20:0.1, 20:0.2, 20:0.3, 20:0.4, 20:0.5, and values between any two of the above.

[0081] Among them, the quantum dot light-emitting material may include, but is not limited to, at least one of single-structure quantum dots, core-shell structure quantum dots, and perovskite semiconductor materials. The single-structure quantum dots are selected from at least one of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds. The II-VI group compounds are selected from at least one of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe. The IV-VI group compounds are selected from at least one of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe. The III-V group compounds are selected from at least one of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, and InAlPSb. The I-III-VI group compounds are selected from at least one of CuInS, CuInSe, and AgInS. The core of the core-shell structure quantum dots is selected from any one of the above single-structure quantum dots, and the shell material of the core-shell structure quantum dots is selected from at least one of CdS, CdTe, CdSeTe, CdZnSe, CdZnS, CdSeS, ZnSe, ZnSeS, and ZnS.

[0082] As an example, the quantum dots of the core-shell structure can be selected from, but not limited to, at least one of CdZnSe / CdZnSe / ZnSe / CdZnS / ZnS, CdZnSe / CdZnSe / CdZnS / ZnSCdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS, and InP / ZnSe / ZnS.

[0083] It should be noted that for the materials of the aforementioned single-structure quantum dots, or the core materials of the core-shell structure quantum dots, or the shell materials of the core-shell structure quantum dots, the chemical formulas provided only indicate the elemental composition and do not indicate the content of each element. For example, CdZnSe only represents the composition of three elements, Cd, Zn, and Se. If the content of each element is to be represented, it corresponds to Cd x Zn 1-x Se, where 0 < x < 1.

[0084] The perovskite semiconductor material is selected from doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the general structural formula of the inorganic perovskite semiconductor is AMX3, where A is Cs + ion, M is a divalent metal cation selected from Pb 2+ , Sn 2+ , Cu 2+ , Ni 2+ , Cd 2+ , Cr 2+ , Mn 2+ , Co 2+ , Fe 2+ , Ge 2+ , Yb 2+ , Eu 2+ and at least one of them, X is a halogen anion selected from Cl - , Br - , I - and at least one of them; the general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, where B is an organic amine cation selected from CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n ≥ 2, M is a divalent metal cation selected from Pb 2+ , Sn 2+ , Cu 2+ , Ni 2+ , Cd2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ at least one of, X is a halogen anion, selected from Cl - 、Br - 、I - at least one of.

[0085] Among them, the material of the electron functional layer 33 includes an electron transport material, and the electron transport material includes one or more of metal oxides, doped metal oxides, IIB-VIA group materials, IIIB-VA group materials, and IB-IIIB-VIA group materials; the metal oxides include one or more of ZnO, TiO2, and SnO2; the metal oxides in the doped metal oxides include one or more of ZnO, TiO2, and SnO2, and the doping elements include one or more of Al, Mg, Li, In, and Ga; the IIB-VIA group materials include one or more of ZnS, ZnSe, CdS, and CdSe; the IIIB-VA group materials include one or more of InP and GaP.

[0086] In some embodiments, the hole mobility of the self-assembled material is greater than or equal to 5×10 -3 cm 2 / V / s and less than or equal to 5×10 -2 cm 2 / V / s; for example, it can be 5×10 -3 cm 2 / V / s, 5.1×10 -3 cm 2 / V / s, 5.2×10 -3 cm 2 / V / s, 5.5×10 -3 cm 2 / V / s, 5.7×10 -3 cm 2 / V / s, 5.9×10 -3 cm 2 / V / s, 6×10 -3 cm 2 / V / s, 6.5×10 -3 cm 2 / V / s, 7×10 -3 cm 2 / V / s, 8×10 -3 cm 2 / V / s, 9×10-3 cm 2 / V / s, 1×10 -2 cm 2 / V / s, 2×10 -2 cm 2 / V / s, 3×10 -2 cm 2 / V / s, 4×10 -2 cm 2 / V / s, 5×10 -2 cm 2 / V / s and values between any two of the above. The self-assembled material has a high hole mobility. When used as the material of the active layer 30, it helps to promote hole injection and block electron injection.

[0087] In some embodiments, the CBM energy level of the self-assembled material is from -3.5 eV to -3 eV; for example, it can be -3.5 eV, -3.4 eV, -3.3 eV, -3.2 eV, -3.1 eV, -3 eV and values between any two of the above. Among them, CBM is the point with the lowest energy level in the conduction band. Selecting a material with a CBM energy level within the above range helps to better block electron leakage.

[0088] The VBM energy level of the self-assembled material is from -5.5 eV to -6.5 eV; for example, it can be -5.5 eV, -5.6 eV, -5.7 eV, -5.8 eV, -5.9 eV, -6 eV, -6.1 eV, -6.2 eV, -6.3 eV, -6.4 eV, -6.5 eV and values between any two of the above. Among them, VBM is the point with the highest energy level in the valence band. Selecting a material with a VBM energy level within the above range helps to better reduce the interfacial barrier between the anode 10 and the light-emitting layer 32.

[0089] In addition, the anode 10 and the cathode 20 are each independently selected from a metal electrode, a carbon electrode, a doped or undoped metal oxide electrode, and a composite electrode; wherein, the material of the metal electrode is selected from at least one of Al, Ag, Cu, Mo, Au, Ba, Ca, Ni, Ir, and Mg; the material of the carbon electrode is selected from at least one of graphite, carbon nanotubes, graphene, and carbon fibers; the material of the doped or undoped metal oxide electrode is selected from at least one of ITO, FTO, ATO, AZO, GZO, IZO, MZO, ITZO, ICO, AMO, SnO2, In2O3, Cd:ZnO, Ga:SnO2; the material of the composite electrode is selected from one of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO2 / Ag / TiO2, TiO2 / Al / TiO2, ZnS / Ag / ZnS, and ZnS / Al / ZnS. Wherein, " / " represents a laminated structure. For example, the composite electrode AZO / Ag / AZO represents an electrode with a three-layer laminated composite structure composed of an AZO layer, an Ag layer, and an AZO layer.

[0090] It can be understood that in addition to the above functional layers, the optoelectronic device 100 can also be provided with some functional layers that are commonly used in optoelectronic devices 100 and are helpful for improving the performance of the optoelectronic device 100, such as an electron blocking layer, an electron injection layer, a hole blocking layer, and / or an interface modification layer, etc.

[0091] It can be understood that the materials and thicknesses of the respective layers of the optoelectronic device 100 can be correspondingly set and adjusted according to the light emission requirements of the optoelectronic device 100.

[0092] It can be understood that the optoelectronic device 100 can be a normal optoelectronic device or an inverted optoelectronic device.

[0093] It can be understood that the optoelectronic device 100 may further include a packaging layer (not shown in the figure), and the packaging layer covers or partially covers the above functional layers to isolate water and oxygen (for example, to make the concentrations of oxygen and water lower than 0.1 ppm), thereby improving the performance stability of the optoelectronic device 100. Specifically, the packaging material used to form the packaging layer can be selected from at least one of UV glue, metal thin film, and glass glue, etc. In a specific embodiment, the packaging material can be acrylic resin or epoxy resin.

[0094] The embodiment of the present application also proposes a preparation method for an optoelectronic device 100. Please refer to Figure 2 , the preparation method includes the following steps:

[0095] S10, providing a prefabricated device, the prefabricated device includes a bottom electrode;

[0096] S20. Prepare an active layer 30 on one side of the bottom electrode;

[0097] S30. Prepare a top electrode on the side of the active layer 30 facing away from the prefabricated device to obtain an optoelectronic device 100;

[0098] Wherein, the bottom electrode is selected from one of the anode 10 and the cathode 20, and the top electrode is selected from the other of the anode 10 and the cathode 20;

[0099] The preparation of the active layer 30 includes: depositing the material of the active layer 30 to obtain the active layer 30, wherein the material of the active layer 30 includes a self-assembled material, and the self-assembled material includes one or more of a first compound and a second compound. Among them, the first compound has the structure shown in formula (1), and the second compound has the structure shown in formula (2):

[0100] (1)

[0101] (2)

[0102] Wherein, M1 is selected from substituted or unsubstituted C1-C30 alkyl;

[0103] M2 is selected from any one of substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted aryl with 6-40 ring atoms, and substituted or unsubstituted heteroaryl with 6-40 ring atoms;

[0104] X1, X2, and X3 are each independently selected from one or more combinations of hydrogen, C1-C30 alkyl, and halogen groups;

[0105] Y1 and Y2 are each independently selected from one or more combinations of hydrogen, hydroxyl group, and C1-C30 alkoxy group, and at least one of Y1 and Y2 is selected from C1-C30 alkoxy group or hydroxyl group;

[0106] When substituted by a substituent, the substituent is independently selected from one or more combinations of D, C1-C10 alkyl, C1-C10 alkoxy, C2-C10 alkoxycarbonyl, C2-C10 alkylcarbonyl, C6-C10 aryl, cyano group, nitro group, mercapto group, hydroxyl group, carboxyl group, amino group, and halogen group each time it appears.

[0107] Briefly, the preparation method of the optoelectronic device 100 may be as follows: According to the film layer stacking sequence of the optoelectronic device 100 described above, the bottom electrode, one or more film layers of the active layer 30, and the top electrode are sequentially prepared from bottom to top, thereby obtaining the optoelectronic device 100. Among them, one or more film layers of the active layer 30 refer to one or more of the first interface layer 31, the light-emitting layer 32, the second interface layer 34, and the electron function layer 33. It can be understood that during actual processing, the currently to-be-prepared film layer can be prepared on the surface of the film layer formed in the previous process.

[0108] It can be understood that the preparation methods of the respective film layers in the optoelectronic device 100 provided in the present application, including the anode 10, the cathode 20, the light-emitting layer 32, the first interface layer 31, the electron function layer 33, and other film layers, can be realized by conventional techniques in the art, such as chemical methods or physical methods. Among them, chemical methods include chemical vapor deposition, sequential ionic layer adsorption and reaction, anodic oxidation, electrodeposition, coprecipitation. Physical methods include physical coating methods and solution methods. Among them, physical coating methods include: thermal evaporation coating, electron beam evaporation coating, magnetron sputtering, multi-arc ion coating, physical vapor deposition, atomic layer deposition, pulsed laser deposition, etc.; solution methods can be spin coating, printing, inkjet printing, blade coating, printing, dip coating, immersion, spraying, roll coating, casting, slot die coating, and bar coating, etc.

[0109] Specifically, in some embodiments, when the active layer 30 includes the light-emitting layer 32, the preparation method of the light-emitting layer 32 includes: providing the material of the light-emitting layer 32, depositing the material of the light-emitting layer 32, and performing a first annealing treatment to obtain the light-emitting layer 32. Among them, the material of the light-emitting layer 32 includes quantum dot light-emitting materials.

[0110] When the solution method is used to prepare the light-emitting layer 32, the material of the light-emitting layer 32 further includes a first solvent, and the first solvent includes one or more of ethane, propane, butane, n-octane, cyclohexane, hexane, and pentane.

[0111] In the material of the light-emitting layer 32, the concentration of the quantum dot light-emitting material is 10 - 30 mg / ml; for example, it can be 10 mg / ml, 15 mg / ml, 20 mg / ml, 25 mg / ml, 30 mg / ml, and values between any two of the above.

[0112] In some embodiments, the material of the light-emitting layer 32 further includes a second material selected from at least one of the self-assembled materials; that is, the material of the light-emitting layer 32 includes the quantum dot light-emitting material and the second material. Accordingly, the prepared light-emitting layer 32 is doped with the second material. Based on this, during actual processing, the quantum dot light-emitting material and the second material can be dispersed in a first solvent to form a mixed solution, and then the mixed solution is deposited on the surface of the previous film layer, and after a first annealing treatment, the light-emitting layer 32 can be obtained.

[0113] Wherein, when the material of the light-emitting layer 32 includes the quantum dot light-emitting material and the second material, in the material of the light-emitting layer 32, the ratio of the total mass of the quantum dot light-emitting material to the total mass of the second material is 20:(0.1 - 0.5).

[0114] Wherein, in the material of the light-emitting layer 32, the concentration of the second material is 0.1 - 0.5 mg / mL; for example, it can be 0.1 mg / ml, 0.2 mg / ml, 0.3 mg / ml, 0.4 mg / ml, 0.5 mg / ml, and values between any two of the above.

[0115] Wherein, the temperature of the first annealing treatment can be 90°C - 110°C; for example, it can be 90°C, 95°C, 100°C, 105°C, 110°C, and values between any two of the above.

[0116] Wherein, the time of the first annealing treatment can be 1 - 10 min; for example, it can be 1 min, 2 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, and values between any two of the above.

[0117] Specifically, in some embodiments, when the active layer 30 includes an electron functional layer 33, the preparation method of the electron functional layer 33 includes: providing the material of the electron functional layer 33, depositing the material of the electron functional layer 33, and performing a second annealing treatment to obtain the electron functional layer 33, wherein the material of the electron functional layer 33 includes an electron transport material.

[0118] When the solution method is used to prepare the electron functional layer 33, the material of the electron functional layer 33 further includes a second solvent, and the second solvent includes one or more of methanol, ethanol, propanol, isopropanol, butanol, cyclohexanol, 2-methyl-2-propanol, and 2-ethyl-1-propanol.

[0119] In the material of the electronic functional layer 33, the concentration of the electron transport material is 10 to 40 mg / ml; for example, it can be 10 mg / ml, 15 mg / ml, 20 mg / ml, 25 mg / ml, 30 mg / ml, 35 mg / ml, 40 mg / ml, and values between any two of the above.

[0120] In some embodiments, the material of the electronic functional layer 33 further includes a third material, and the third material is selected from at least one of the self-assembled materials; that is, the material of the electronic functional layer 33 includes the electron transport material and the third material. Correspondingly, the prepared electronic functional layer 33 is doped with the third material. Based on this, during actual processing, the electron transport material and the third material can be dispersed in a second solvent to form a mixed solution, and then the mixed solution is deposited on the surface of the previous film layer, and after the first annealing treatment, the electronic functional layer 33 can be obtained.

[0121] Wherein, when the material of the electronic functional layer 33 includes the electron transport material and the third material, in the material of the electronic functional layer 33, the ratio of the total mass of the electron transport material to the total mass of the third material is 20:(0.1 - 0.5).

[0122] Wherein, in the material of the electronic functional layer 33, the concentration of the third material is 0.1 to 0.5 mg / mL; for example, it can be 0.1 mg / ml, 0.2 mg / ml, 0.3 mg / ml, 0.4 mg / ml, 0.5 mg / ml, and values between any two of the above.

[0123] Wherein, the temperature of the second annealing treatment can be 90°C to 110°C; for example, it can be 90°C, 95°C, 100°C, 105°C, 110°C, and values between any two of the above.

[0124] Wherein, the time of the second annealing treatment can be 5 to 30 min; for example, it can be 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, 15 min, 20 min, 25 min, 30 min, and values between any two of the above.

[0125] In some embodiments, the active layer 30 further includes a second interface layer 34, which is formed by the interaction of at least part of a second material in the light-emitting layer 32 and at least part of a third material in the electron-functional layer 33 and aggregates at the interface between the two. Correspondingly, the preparation of the active layer 30 includes the following steps: depositing the first film layer material to obtain a first film layer, then depositing the second film layer material on one side of the first film layer to form a second film layer, and at least part of the second material and at least part of the third material interact to form the second interface layer 34 between the first film layer and the second film layer. Herein, the first film layer, the second film layer, the first film layer material, and the second film layer material are named for convenience of description. Specifically, one of the light-emitting layer 32 and the electron-functional layer 33 is named as the first film layer, and the other of the light-emitting layer 32 and the electron-functional layer 33 is named as the second film layer. One of the materials of the light-emitting layer 32 and the materials of the electron-functional layer 33 is named as the first film layer material, and the other of the materials of the light-emitting layer 32 and the materials of the electron-functional layer 33 is named as the second film layer material.

[0126] Specifically, in some embodiments, when the active layer 30 includes a first interface layer 31, the preparation of the first interface layer 31 includes: providing the material of the first interface layer 31, depositing the material of the first interface layer 31, and performing a third annealing treatment to obtain the first interface layer 31. Herein, the material of the first interface layer 31 includes a first material, and the first material is selected from at least one of the self-assembled materials.

[0127] When the first interface layer 31 is prepared by a solution method, the material of the first interface layer 31 further includes a third solvent, and the third solvent includes one or more of methanol, ethanol, isopropanol, ethyl acetate, toluene, dichloromethane, acetonitrile, chloroform, and ether.

[0128] In the material of the first interface layer 31, the concentration of the first material is 0.5 - 2 mg / mL; for example, it can be 0.5 mg / ml, 0.8 mg / ml, 1 mg / ml, 1.1 mg / ml, 1.2 mg / ml, 1.5 mg / ml, 1.8 mg / ml, 2 mg / ml, and values between any two of the above.

[0129] Herein, the temperature of the third annealing treatment can be 90°C - 110°C; for example, it can be 90°C, 95°C, 100°C, 105°C, 110°C, and values between any two of the above.

[0130] Herein, the time of the third annealing treatment can be 5 - 15 min; for example, it can be 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, 15 min, and values between any two of the above.

[0131] It can be understood that when the active layer 30 is composed of two or more film layers, when any two adjacent film layers are prepared by the solution method, the solvents used respectively are orthogonal solvents, so as to avoid the solvent of the next film layer eroding the previous film layer when preparing the next film layer.

[0132] This application also relates to a display device, which includes the optoelectronic device 100 provided by this application, or the optoelectronic device 100 prepared by the above preparation method. The display device can be any electronic product with a display function. The electronic product includes but is not limited to a smart phone, a tablet computer, a notebook computer, a digital camera, a digital video camera, a smart wearable device, a smart weighing electronic scale, a vehicle-mounted display, a television or an e-book reader. Among them, the smart wearable device can be, for example, a smart bracelet, a smart watch, a virtual reality (VR) helmet, etc.

[0133] The following specifically describes this application through specific embodiments. The following embodiments are only partial embodiments of this application and do not limit this application. The raw materials used in the following embodiments are all commercially available products unless otherwise specified.

[0134] Example 1

[0135] This embodiment provides a QLED and its preparation method. The structure of the QLED device is ITO / CdZnSe+Me-4PAcz / ZnO / Ag. The preparation method specifically includes the following steps:

[0136] Step 1: After cleaning and drying the ITO substrate (with a thickness of 100 nm), it is treated in an ultraviolet ozone cleaning instrument for 15 min.

[0137] Step 2: Disperse Me-4PAcz and CdSe / CdS quantum dots in n-hexane to obtain a mixed solution. In the mixed solution, the concentration of CdSe / CdS quantum dots is 20 mg / ml, and the concentration of Me-4PAcz is 0.2 mg / ml. Spin-coat the mixed solution on the ITO substrate at a spin-coating speed of 2000 rpm for 30 s, and then heat it at 100 °C for 5 min to obtain a light-emitting layer with a thickness of 30 nm.

[0138] Step 3: Spin-coat an ethanol solution of ZnO (ZnO concentration is 30 mg / ml) on the light-emitting layer at a spin-coating speed of 3000 rpm for 30 s, and then heat it at 100 °C for 15 min to obtain an electron transport layer with a thickness of 20 nm.

[0139] Step 4: Evaporate Ag on the electron transport layer by thermal evaporation. During evaporation, the vacuum degree is 3×10 -4Pa, the evaporation rate was 1 Å / s, and the time was 200 s to obtain a cathode with a thickness of 20 nm.

[0140] Step 5: The device prepared in Step 5 was encapsulated with epoxy resin to obtain a QLED device.

[0141] Example 2

[0142] This example is basically the same as Example 1, except that in this example, a first interface layer is further provided between the anode and the light-emitting layer. Correspondingly, between Steps 1 and 2, it further includes:

[0143] Step 1-2: 2PAcz was dispersed in ethanol to prepare a mixed solution with a concentration of 1 mg / ml of 2PAcz. The mixed solution was spin-coated on the ITO substrate processed in Step 1 at a spin-coating speed of 3000 rpm for 30 s, and then heated at 100 °C for 10 min to obtain a first interface layer with a thickness of 3 nm. The surface of the first interface layer was used to prepare the light-emitting layer.

[0144] In addition, other parameters and steps remain unchanged.

[0145] Example 3

[0146] This example is basically the same as Example 2, except that in this example, Me-4PAcz is doped in the electron transport layer, and in the electron transport layer, the mass ratio of ZnO to Me-4PAcz is 30:0.2, and a second interface layer is formed between the light-emitting layer and the electron transport layer.

[0147] Correspondingly, Step 3 is changed to:

[0148] Me-4PAcz and ZnO nanoparticles were dispersed in ethanol to obtain a mixed solution, and in the mixed solution, the concentration of ZnO was 30 mg / ml and the concentration of Me-4PAcz was 0.2 mg / ml. The mixed solution was spin-coated on the light-emitting layer at a spin-coating speed of 3000 rpm for 30 s, and then heated at 100 °C for 15 min to obtain an electron transport layer with a thickness of 20 nm. In addition, other parameters and steps remain unchanged.

[0149] Example 4

[0150] This example is basically the same as Example 3, except that in this example, the thickness of the first interface layer is changed to 1 nm, and correspondingly, in Step 1-2, the spin-coating time is changed to 50 s.

[0151] In addition, other parameters and steps remain unchanged.

[0152] Example 5

[0153] This embodiment is basically the same as Embodiment 3, except that in this embodiment, the thickness of the first interface layer is changed to 5 nm. Correspondingly, in Step 1-2, the spin-coating time is changed to 20 s.

[0154] In addition, other parameters and steps remain unchanged.

[0155] Embodiment 6

[0156] This embodiment is basically the same as Embodiment 3, except that in this embodiment, the thickness of the interface layer is changed to 7 nm. Correspondingly, in Step 1-2, the spin-coating time is changed to 15 s.

[0157] In addition, other parameters and steps remain unchanged.

[0158] Embodiment 7

[0159] This embodiment is basically the same as Embodiment 3, except that in this embodiment, 2PAcz is changed to octadecyltrichlorosilane in Step 1-2.

[0160] Embodiment 8

[0161] This embodiment is basically the same as Embodiment 3, except that in this embodiment, 2PAcz is changed to ethyl phenylphosphonate in Step 1-2.

[0162] Embodiment 9

[0163] This embodiment is basically the same as Embodiment 3, except that in this embodiment, there is no first interface layer in the device, but both the light-emitting layer and the electron transport layer are doped with Me-4PAcz. Correspondingly, in the preparation method, Step 1-2 is omitted, and the light-emitting layer is directly prepared on ITO.

[0164] Embodiment 10

[0165] This embodiment is basically the same as Embodiment 1, except that in this embodiment, the light-emitting layer is not doped with Me-4PAcz, but the electron transport layer is doped with Me-4PAcz, and in the electron transport layer, the mass ratio of ZnO to Me-4PAcz is 30:0.2. The structure of the device in this comparative example is ITO / CdZnSe / ZnO + Me-4PAcz / Ag. Correspondingly, in the preparation steps:

[0166] In Step 2, Me-4PAcz is not added to the mixed solution;

[0167] Step 3 is changed to: Disperse Me-4PAcz and ZnO nanoparticles in ethanol to obtain a mixed solution. In the mixed solution, the concentration of ZnO is 30 mg / ml, and the concentration of Me-4PAcz is 0.2 mg / ml. Spin-coat the mixed solution on the light-emitting layer at a spin-coating speed of 3000 rpm for 30 s, and then heat it at 100 °C for 15 min to obtain an electron transport layer with a thickness of 20 nm.

[0168] In addition, other parameters and steps remain unchanged.

[0169] Comparative Example 1

[0170] This comparative example is basically the same as Example 1, except that the structure of the device in this comparative example is ITO / CdZnSe / ZnO / Ag. Correspondingly, in the preparation steps, Step 2 is omitted. In addition, other parameters and steps remain unchanged.

[0171] Experimental Example

[0172] Perform performance tests on the quantum dot light-emitting diodes of the examples and comparative examples. The performance test items include brightness L test, lifetime T95 test, lifetime T95@1000 nit test, current efficiency C.E test, and stability test. The test results are shown in Tables 1 to 4.

[0173] Among them, the test methods for brightness L and current efficiency C.E are as follows: Use a Fosdick FPD optical property measurement device, and build an efficiency test system by controlling a QE PRO spectrometer, a Keithley 2400, and a Keithley 6485 through LabView to measure parameters such as voltage, current, brightness, and emission spectrum, and calculate the current efficiency C.E through calculation;

[0174] The test method for lifetime T95@1000 nit is: The time required for the brightness of the device to decrease to a certain proportion of the maximum brightness under constant current or voltage drive. The time when the brightness drops to 95% of the maximum brightness is defined as T95, and this lifetime is the measured lifetime. To shorten the test cycle, the device lifetime test is usually carried out by accelerating device aging at high brightness, and the lifetime at high brightness is obtained by fitting with an extended exponential decay brightness decay fitting formula. For example, the lifetime at 1000 nit is denoted as T95@1000 nit. The specific calculation formula is as follows:

[0175]

[0176] Among them, T95 L is the lifetime at low brightness, T95 H is the measured lifetime at high brightness, L H is the device accelerated to the maximum brightness, L LIt is 1000 nits. A is the acceleration factor. In this experiment, the value of A is obtained as 1.7 by measuring the lifetimes of several groups of green QLED devices at the rated brightness.

[0177] The method for the stability test is as follows: The initial brightness L, lifetime T95, lifetime T95@1000 nits, and current efficiency C.E of the devices in the examples and comparative examples are tested. After recording the initial data, they are placed in a sealed environment at a temperature of 25°C and a humidity of 60%. After 1000 hours, the brightness L, lifetime T95, lifetime T95@1000 nits, and current efficiency C.E after placement are recorded, and the attenuation rate is calculated to characterize the stability.

[0178] Table 1

[0179]

[0180]

[0181] Table 2

[0182]

[0183] Table 3

[0184]

[0185]

[0186] Table 4

[0187] C.E (cd / A) C.E (cd / A) after placement C.E attenuation rate (%) Example 1 35.52 23.34 34.3 Example 2 57.55 47.22 17.9 Example 3 63.04 61.16 3.0 Example 4 59.38 53.88 9.3 Example 5 60.05 56.92 5.2 Example 6 38.12 19.35 49.2 Example 7 62.26 59.89 3.8 Example 8 62.91 60.47 3.9 Example 9 47.49 32.51 31.5 Example 10 34.16 12.96 62.1 Comparative Example 1 35.89 9.55 73.4

[0188] As can be seen from the above table, Examples 1 to 10 all have lower brightness attenuation rates, lifetime attenuation rates, and current efficiency attenuation rates than Comparative Example 1, and higher initial T95. This shows that compared with the QLED devices without a hole functional layer, the devices of the present application, by setting an active layer containing a self-assembled material, greatly improve the stability of the QLED devices without a hole functional layer and extend their lifetimes. At the same time, from the overall high initial brightness, initial lifetime, and initial current efficiency shown by the devices in the above examples, the devices proposed in the present application have good quality.

[0189] Among Examples 1 to 3 and Examples 9 to 10, Example 3 shows the highest brightness, lifetime, and current efficiency and the lowest attenuation rate. This shows that in the case of setting the first interface layer in Example 3, a certain amount of self-assembled material is incorporated into the light-emitting layer and the electron functional layer to form a second interface layer, which can significantly improve the brightness, current efficiency, lifetime, and stability, and construct a high-quality device without a hole functional layer.

[0190] The above has introduced the technical solutions provided by the embodiments of the present application in detail. Specific examples are used herein to elaborate on the principles and implementation manners of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. An optoelectronic device, characterized in that, The optoelectronic device includes a stacked anode, an active layer, and a cathode. The material of the active layer includes a self-assembled material, and the self-assembled material includes one or more of a first compound and a second compound. Among them, the first compound has the structure shown in formula (1), and the second compound has the structure shown in formula (2): (1) (2) Wherein, M1 is selected from substituted or unsubstituted C1-C30 alkyl; M2 is selected from any one of substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted aryl with 6-40 ring atoms, and substituted or unsubstituted heteroaryl with 6-40 ring atoms; X1, X2, and X3 are each independently selected from one or more combinations of hydrogen, C1-C30 alkyl, and halogen groups; Y1 and Y2 are each independently selected from one or more combinations of hydrogen, hydroxyl, and C1-C30 alkoxy, and at least one of Y1 and Y2 is selected from C1-C30 alkoxy or hydroxyl; When substituted by a substituent, the substituent is independently selected from one or more combinations of D, C1-C10 alkyl, C1-C10 alkoxy, C2-C10 alkoxycarbonyl, C2-C10 alkylcarbonyl, C6-C10 aryl, cyano, nitro, mercapto, hydroxyl, carboxyl, amino, and halogen groups each time it appears.

2. The optoelectronic device according to claim 1, characterized in that, The hole mobility of the self-assembled material is greater than or equal to 5×10 -3 cm 2 / V / s and less than or equal to 5×10 -2 cm 2 / V / s; and / or, The CBM energy level of the self-assembled material is -3.5 eV to -3 eV; and / or, The VBM energy level of the self-assembled material is -5.5 eV to -6.5 eV; and / or, M1 is selected from C1-C20 alkyl; and / or, X1, X2, and X3 are each independently selected from one or more combinations of C1-C30 alkyl and halogen groups; and / or, When Y1 and Y2 are each independently selected from one or more of hydrogen and C1-C30 alkoxy, M2 is selected from C1-C30 alkyl and aryl with 6-14 ring atoms; when Y1 and Y2 are each independently selected from hydroxyl, M2 is selected from the following structures: Wherein, n is any integer from 1 to 10, and n1 and n2 are each independently selected from any integer from 1 to 4; R 1 and R 2 each independently selected from one or more combinations of a halogen group, a substituted or unsubstituted C1-C30 alkoxy group; when substituted by a substituent, each occurrence of the substituent is independently selected from one or more combinations of D, a C1-C10 alkyl group, a C1-C10 alkoxy group, a C2-C10 alkoxycarbonyl group, a C2-C10 alkylcarbonyl group, a C6-C10 aryl group, a cyano group, a nitro group, a mercapto group, a hydroxy group, a carboxyl group, an amino group, and a halogen group.

3. The optoelectronic device according to claim 2, characterized in that, The first compound includes one or more of the following compounds P1 to P2; and / or, The second compound includes one or more of the following compounds P3 to P7; 4. The optoelectronic device according to any one of claims 1 to 3, characterized in that, The active layer includes at least one of a light-emitting layer and an electron-functional layer. When the active layer includes the light-emitting layer and the electron-functional layer, the electron-functional layer is located between the light-emitting layer and the cathode; and / or, The active layer includes a first interface layer disposed between the anode and the active layer. The material of the first interface layer includes a first material, and the first material is selected from at least one of the self-assembled materials.

5. The optoelectronic device according to claim 4, characterized in that, The thickness of the first interface layer is 1-5 nm; and / or, The material of the light-emitting layer includes a second material, and the second material is selected from at least one of the self-assembled materials; and / or, The material of the electron-functional layer includes a third material, and the third material is selected from at least one of the self-assembled materials.

6. The optoelectronic device according to claim 5, characterized in that, When the active layer includes the light-emitting layer and the electron-functional layer, the active layer further includes a second interface layer located between the light-emitting layer and the electron-functional layer, and the material of the second interface layer includes at least part of the second material and at least part of the third material.

7. The optoelectronic device according to claim 6, characterized in that, When the material of the light-emitting layer includes a quantum dot light-emitting material and the second material, in the light-emitting layer, the ratio of the total mass of the quantum dot light-emitting material to the total mass of the second material is 20:(0.1 - 0.5); and / or, When the material of the electron-functional layer includes an electron transport material and the third material, in the electron-functional layer, the ratio of the mass of the electron transport material to the mass of the third material is 20:(0.1 - 0.5); and / or, The thickness of the second interface layer is 1 - 5 nm.

8. The optoelectronic device according to claim 4, characterized in that, The anode and the cathode are each independently selected from a metal electrode, a carbon electrode, a doped or undoped metal oxide electrode, and a composite electrode; wherein, the material of the metal electrode is selected from at least one of Al, Ag, Cu, Mo, Au, Ba, Ca, Ni, Ir, and Mg; the material of the carbon electrode is selected from at least one of graphite, carbon nanotubes, graphene, and carbon fiber; the material of the doped or undoped metal oxide electrode is selected from at least one of ITO, FTO, ATO, AZO, GZO, IZO, MZO, ITZO, ICO, AMO, SnO2, In2O3, Cd:ZnO, Ga:SnO2; the material of the composite electrode is selected from one of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO2 / Ag / TiO2, TiO2 / Al / TiO2, ZnS / Ag / ZnS, and ZnS / Al / ZnS; and / or, The material of the light-emitting layer includes quantum dot light-emitting materials, and the quantum dot light-emitting materials are selected from at least one of single-structure quantum dots, core-shell structure quantum dots, and perovskite semiconductor materials. The single-structure quantum dots are selected from at least one of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds. The II-VI group compounds are selected from at least one of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe. The IV-VI group compounds are selected from at least one of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe. The III-V group compounds are selected from at least one of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, and InAlPSb. The I-III-VI group compounds are selected from at least one of CuInS, CuInSe, and AgInS. The core of the core-shell structure quantum dots is selected from any one of the above single-structure quantum dots, and the shell material of the core-shell structure quantum dots is selected from at least one of CdS, CdTe, CdSeTe, CdZnSe, CdZnS, CdSeS, ZnSe, ZnSeS, and ZnS. The perovskite semiconductor materials are selected from doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors;The structural general formula of the inorganic perovskite semiconductor is AMX3, where A is Cs; + ion, M is a divalent metal cation selected from 2+ Pb 2+ Sn 2+ Cu 2+ Ni 2+ Cd 2+ Cr 2+ Mn 2+ Co 2+ Fe 2+ Ge 2+ Yb 2+ Eu - at least one of them, and X is a halogen anion selected from - Cl - Br n-2 I + at least one of them; the structural general formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, where B is an organic amine cation selected from n CH3(CH2) 2+ NH3 2+ or 2+ [NH3(CH2) 2+ NH3] 2+ where n≥2, M is a divalent metal cation selected from 2+ Pb 2+ Sn 2+ Cu 2+ Ni 2+ Cd 2+ Cr 2+ Mn 2+ Co - Fe - Ge - Yb 2+ Eu 2+ at least one of them, and X is a halogen anion selected from - Cl - Br - I - at least one of them; and / or The material of the electron-functional layer includes an electron transport material, and the electron transport material includes one or more of a metal oxide, a doped metal oxide, a IIB-VIA group material, a IIIB-VA group material, and a IB-IIIB-VIA group material; the metal oxide includes one or more of ZnO, TiO2, and SnO2; the metal oxide in the doped metal oxide includes one or more of ZnO, TiO2, and SnO2, and the doping element includes one or more of Al, Mg, Li, In, and Ga; the IIB-VIA group material includes one or more of ZnS, ZnSe, CdS, and CdSe; the IIIB-VA group material includes one or more of InP and GaP.

9. A method for preparing an optoelectronic device, characterized in that, Comprising the following steps: Providing a prefabricated device, the prefabricated device including a bottom electrode; Preparing an active layer on one side of the bottom electrode; Preparing a top electrode on the side of the active layer facing away from the prefabricated device to obtain an optoelectronic device; Wherein, the bottom electrode is selected from one of the anode and the cathode, and the top electrode is selected from the other of the anode and the cathode; The preparation of the active layer includes: depositing the materials of the active layer to obtain the active layer, wherein the materials of the active layer include self-assembled materials, and the self-assembled materials include one or more of a first compound and a second compound. Among them, the first compound has the structure shown in formula (1), and the second compound has the structure shown in formula (2): (1) (2) Wherein, M1 is selected from substituted or unsubstituted C1-C30 alkyl groups; M2 is selected from any one of substituted or unsubstituted C1-C30 alkyl groups, substituted or unsubstituted aryl groups with 6 to 40 ring atoms, and substituted or unsubstituted heteroaryl groups with 6 to 40 ring atoms; X1, X2, and X3 are each independently selected from one or more combinations of hydrogen, C1-C30 alkyl groups, and halogen groups; Y1 and Y2 are each independently selected from one or more combinations of hydrogen, hydroxyl groups, and C1-C30 alkoxy groups, and at least one of Y1 and Y2 is selected from C1-C30 alkoxy groups or hydroxyl groups; When substituted by substituents, each occurrence of the substituent is independently selected from one or more combinations of D, C1-C10 alkyl groups, C1-C10 alkoxy groups, C2-C10 alkoxy carbonyl groups, C2-C10 alkyl carbonyl groups, C6-C10 aryl groups, cyano groups, nitro groups, mercapto groups, hydroxyl groups, carboxyl groups, amino groups, and halogen groups.

10. The preparation method according to claim 9, characterized in that, The active layer includes a light-emitting layer. The preparation of the light-emitting layer includes: providing the materials of the light-emitting layer, depositing the materials of the light-emitting layer, and performing a first annealing treatment to obtain the light-emitting layer, wherein the materials of the light-emitting layer include quantum dot light-emitting materials; and / or, The active layer includes an electron functional layer. The preparation of the electron functional layer includes: providing the materials of the electron functional layer, depositing the materials of the electron functional layer, and performing a second annealing treatment to obtain the electron functional layer, wherein the materials of the electron functional layer include electron transport materials; and / or, The active layer includes a first interface layer. The preparation of the first interface layer includes: providing the materials of the first interface layer, depositing the materials of the first interface layer, and performing a third annealing treatment to obtain the first interface layer, wherein the materials of the first interface layer include a first material, and the first material is selected from at least one of the self-assembled materials.

11. The preparation method according to claim 10, characterized in that, The materials of the light-emitting layer further include a first solvent, and the first solvent includes one or more of ethane, propane, butane, n-octane, cyclohexane, hexane, and pentane; and / or, The materials of the light-emitting layer further include a second material, and the second material is selected from at least one of the self-assembled materials; and / or, The temperature of the first annealing treatment is 90°C to 110°C; and / or, The time of the first annealing treatment is 1 to 10 minutes; and / or, The materials of the electron functional layer further include a second solvent, and the second solvent includes one or more of methanol, ethanol, propanol, isopropanol, butanol, cyclohexanol, 2-methyl-2-propanol, and 2-ethyl-1-propanol; and / or, The materials of the electron functional layer further include a third material, and the third material is selected from at least one of the self-assembled materials; and / or, The temperature of the second annealing treatment is 90°C to 110°C; and / or, The time of the second annealing treatment is 5 to 30 minutes; and / or, The material of the first interface layer further includes a third solvent, and the third solvent includes one or more of methanol, ethanol, isopropanol, ethyl acetate, toluene, dichloromethane, acetonitrile, chloroform, and ether; and / or, The temperature of the third annealing treatment is 90°C to 110°C; and / or, The time of the third annealing treatment is 5 to 15 minutes.

12. The preparation method according to claim 11, characterized in that, In the material of the first interface layer, the concentration of the first material is 0.5 to 2 mg / mL; and / or, When the material of the light-emitting layer includes the quantum dot light-emitting material and the second material, in the material of the light-emitting layer, the ratio of the total mass of the quantum dot light-emitting material to the total mass of the second material is 20:(0.1 to 0.5); and / or, In the material of the light-emitting layer, the concentration of the second material is 0.1 to 0.5 mg / mL; and / or, In the material of the light-emitting layer, the concentration of the quantum dot light-emitting material is 10 to 30 mg / ml; and / or, When the material of the electron functional layer includes the electron transport material and the third material, in the material of the electron functional layer, the ratio of the mass of the electron transport material to the mass of the third material is 20:(0.1 to 0.5); and / or, In the material of the electron transport layer, the concentration of the third material is 0.1 to 0.5 mg / mL.

13. The preparation method according to claim 12, characterized in that, The active layer includes the electron functional layer, the light-emitting layer, and a second interface layer; One of the light-emitting layer and the electron functional layer is named as the first film layer, and the other of the light-emitting layer and the electron functional layer is named as the second film layer. One of the materials of the light-emitting layer and the materials of the electron functional layer is named as the first film layer material, and the other of the materials of the light-emitting layer and the materials of the electron functional layer is named as the second film layer material; The preparation of the active layer includes: Depositing the first film layer material to obtain the first film layer, and then depositing the second film layer material on one side of the first film layer to form the second film layer. At least part of the second material and at least part of the third material interact to form the second interface layer between the first film layer and the second film layer.

14. A display device, characterized in that, Including the optoelectronic device according to any one of claims 1 to 8, or including the optoelectronic device prepared by the preparation method according to any one of claims 9 to 13.

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