Nano material, ink and preparation method thereof, thin film, luminescent device and display device

Abstract

The invention discloses a nanometer material, ink, a preparation method, a film, a light-emitting device and a display device, the nanometer material comprises quantum dots, a first ligand and a second ligand, the first ligand is a compound containing disulfide bonds, and the second ligand is a thiol compound. The nano material disclosed by the invention has relatively high stability.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a nanomaterial, an ink and its preparation method, a thin film, a light-emitting device, and a display device. Background Technology

[0002] Quantum dots (QDs), also known as semiconductor nanocrystals, have unique luminescent properties, such as wide excitation peaks, narrow emission peaks, and tunable emission spectra, making them promising for applications in the field of optoluminescence.

[0003] The stability of existing quantum dots is poor and needs to be further improved. Summary of the Invention

[0004] In view of this, this application provides a nanomaterial, an ink and a method for preparing it, a thin film, a light-emitting device, and a display device.

[0005] The embodiments of this application are implemented as follows: a nanomaterial includes quantum dots, a first ligand, and a second ligand, wherein the first ligand is a compound containing disulfide bonds, and the second ligand is a thiol compound.

[0006] Accordingly, this application also provides an ink comprising a solvent and the nanomaterial.

[0007] Accordingly, this application also provides a method for preparing ink, comprising the following steps:

[0008] A quantum dot solution is provided, the quantum dot solution comprising quantum dots and a solvent, and the quantum dot solution is mixed with a compound containing disulfide bonds and a thiol compound to obtain a mixture;

[0009] Heating the mixture yields ink comprising a solvent and nanomaterials, the nanomaterials comprising quantum dots, a first ligand coordinated to the quantum dots, and a second ligand coordinated to the quantum dots, the first ligand being a compound containing disulfide bonds and the second ligand being a thiol compound.

[0010] Accordingly, this application also provides a thin film comprising the nanomaterial, or the thin film is prepared from the ink by a film-forming process.

[0011] Accordingly, this application also provides a light-emitting device, comprising an anode, a light-emitting layer and a cathode stacked sequentially, wherein the light-emitting layer comprises the nanomaterial, or the light-emitting layer is prepared by the ink through a film-forming process.

[0012] Accordingly, this application also provides a display device, including the light-emitting device described above.

[0013] The nanomaterials described in this application have high stability. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a flowchart illustrating a method for preparing quantum dot ink according to an embodiment of this application;

[0016] Figure 2 This is a schematic diagram of the structure of a light-emitting device provided in an embodiment of this application.

[0017] Figure Labels

[0018] Light-emitting device 100; anode 10; light-emitting layer 20; cathode 30; electron transport layer 40; hole transport layer 50. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application.

[0020] In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in its actual use or operating state, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. Furthermore, in the description of this application, the term "comprising" means "including but not limited to". The terms first, second, third, etc., are used merely as illustrative purposes and do not impose numerical requirements or establish a numerical order.

[0021] In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural.

[0022] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c," or "at least one of a, b, and c," can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0023] In this application, the term "on" forming another layer on a certain layer is a broad concept. It can mean that the formed other layer is adjacent to a certain layer, or it can mean that there are other spacer structures between the other layer and the certain layer. For example, when a second electrode is formed "on" a first charge carrier functional layer, the term "on" can mean that the formed second electrode is adjacent to the first charge carrier functional layer, or it can mean that there are other spacer structures between the second electrode and the first charge carrier functional layer, such as a light-emitting layer.

[0024] 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 merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical 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 single numbers within the range, such as 1, 2, 3, 4, 5, and 6, whichever applies. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the range referred to.

[0025] In this application, "substitution" means that the hydrogen atom in the substituent is replaced by the substituent.

[0026] In this application, when no linking site is specified in the group, it means that any linkable site in the group is selected as the linking site.

[0027] 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.

[0028] In this application, "substituted or unsubstituted" means that the defined group may or may not be substituted. When the defined group is substituted, it should be understood that the defined group can be substituted by one or more substituents R, wherein R is selected from, but is not limited to: deuterium, cyano, isocyano, nitro or halogen, C1-30 alkyl, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, heteroaromatic group containing 5-20 ring atoms, -NR'R", silyl, carbonyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, halocarbamoyl, etc. Formyl, isocyanate, thiocyanate, isothiocyanate, hydroxyl, trifluoromethyl, and the above groups may be further substituted with substituents acceptable in the art; it is understood that R' and R" in -NR'R" are independently selected from, but not limited to: H, deuterium, cyano, isocyano, nitro or halogen, C1-10 alkyl, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, and heteroaromatic group containing 5-20 ring atoms.

[0029] In this application, "ring atom number" refers to the number of atoms in the ring itself of a structural compound (e.g., a monocyclic compound, a fused-ring compound, a cross-linked compound, a carbocyclic compound, or a heterocyclic compound) obtained by atomic bonding to form a ring. 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 "ring atom number" described below unless otherwise specified. For example, a benzene ring has 6 ring atoms, a naphthalene ring has 10 ring atoms, and a thiophene group has 5 ring atoms.

[0030] In this application, "aryl or aromatic group" refers to an aromatic hydrocarbon group derived from an aromatic ring compound by removing one hydrogen atom. It can be a monocyclic aryl, a fused-ring aryl, or a polycyclic aryl. For polycyclic rings, at least one is an aromatic ring system. For example, "substituted or unsubstituted aryl having 6 to 40 ring atoms" refers to an aryl containing 6 to 40 ring atoms, preferably a substituted or unsubstituted aryl having 6 to 30 ring atoms, more preferably a substituted or unsubstituted aryl having 6 to 18 ring atoms, and particularly preferably a substituted or unsubstituted aryl having 6 to 14 ring atoms, and optionally further substituted on the aryl group; suitable examples include, but are not limited to: phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthrene, fluoranyl, triphenylene, pyrene, perylene, tetraphenyl, fluorenyl, dinaphthylphenyl, acenaphthyl and their derivatives. Understandably, multiple aryl groups can also be interrupted by short non-aromatic units (e.g., <10% non-H atoms, such as C, N, or O atoms), specifically acenaphthene, fluorene, or 9,9-diarylfluorene, triarylamine, and diaryl ether systems should also be included in the definition of aryl.

[0031] In this application, "heteroaryl or heteroaromatic group" refers to an aryl group in which at least one carbon atom is replaced by a non-carbon atom, which can be an N atom, O atom, S atom, etc. For example, "substituted or unsubstituted heteroaryl group having 5 to 40 ring atoms" refers to a heteroaryl group having 5 to 40 ring atoms, preferably a substituted or unsubstituted heteroaryl group having 6 to 30 ring atoms, more preferably a substituted or unsubstituted heteroaryl group having 6 to 18 ring atoms, and particularly preferably a substituted or unsubstituted heteroaryl group having 6 to 14 ring atoms. The heteroaryl group may optionally be further substituted, and suitable examples include, but are not limited to: thiophene, furanyl, pyrroleyl, imidazole, triazolyl, imidazoleyl, diazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridineyl, pyridazinyl, etc. Azinyl, quinolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridinylpyrimidinyl, pyridinylpyrazinyl, pyrazinylpyrazinyl, isoquinolinyl, indolyl, carbazoleyl, benzothiopheneyl, benzofuranyl, indolyl, carbazoleyl, pyrroloimidazolyl, pyrrolopyrrololyl, thienopyrrololyl, thienopyrrololyl, furanolol, furanol, thienofuranyl, benzoisoxazolyl, benzoisothiazolyl, benzoimidazolyl, quinolinyl, isoquinolinyl, o-diazonaphthyl, quinoxalinyl, phenanthridine, primidyl, quinazolinyl, quinazolinone, dibenzothiopheneyl, dibenzofuranyl, carbazoleyl and their derivatives.

[0032] In this application, "alkyl" can refer to straight-chain or branched alkyl. The number of carbon atoms in an alkyl group can be 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. Phrases containing this term, such as "C1-9 alkyl," refer to alkyl groups containing 1 to 9 carbon atoms, and each time it appears, it can independently be C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl, or C9 alkyl. 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, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3,7-dimethyloctyl, n-nonyl, n-decyl, adamantyl, 2-ethyldecyl, 2-butyldecyl, 2-hexyldecyl, 2-octyldecyl The compounds include: n-undecyl, n-dodecyl, 2-ethyldodecyl, 2-butyldodecyl, 2-hexyldodecyl, 2-octyldodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, n-hexadecyl, 2-ethylhexadecyl, 2-butylhexadecyl, 2-hexylhexadecyl, 2-octylhexadecyl, n-heptadecyl, n-octadecyl, n-heptadecyl, n-eicosyl, 2-ethyleicosyl, 2-butyleicosyl, 2-hexyleicosyl, 2-octyleicosyl, n-monodecyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, n-eicosyl, and adamantane.

[0033] In this application, "alkoxy" refers to a group with the structure "-O-alkyl", that is, an alkyl group as defined above that is attached to other groups via an oxygen atom. Suitable examples of phrases containing this term include, but are not limited to: methoxy (-O-CH3 or -OMe), ethoxy (-O-CH2CH3 or -OEt), and tert-butoxy (-OC(CH3)3 or -OtBu).

[0034] The stability of quantum dots has a significant impact on the stability, efficiency, and lifespan of devices containing quantum dots. Quantum dot surfaces are typically linked with ligands, and existing ligands on quantum dot surfaces can detach, migrate, or degrade over time, thus affecting device performance. Furthermore, the long-term stability of quantum dot inks places high demands on printing stability and device stability, especially given the potential for ligand detachment, migration, and degradation on the quantum dot surface over time, which in turn affects device performance.

[0035] The technical solution of this application is as follows:

[0036] In a first aspect, embodiments of this application provide a nanomaterial comprising quantum dots, a first ligand, and a second ligand, wherein the first ligand is a compound containing disulfide bonds, and the second ligand is a thiol compound.

[0037] Understandably, the first ligand is coordinated with the quantum dot, and the second ligand is coordinated with the quantum dot.

[0038] In at least one embodiment, the nanomaterial comprises the quantum dot, the first ligand, and the second ligand.

[0039] The compound containing disulfide bonds has the structural formula shown in formula (I):

[0040]

[0041] The thiol compound has the structural formula shown in formula (II):

[0042] R3—OH

[0043] (II)

[0044] Among them, R1, R2, and R3 are each independently, including but not limited to, substituted or site-substituted C3 to C4. 20 Straight-chain alkyl, substituted or substituted C3-C 20 Straight-chain alkoxy, substituted or substituted C3-C 20 Straight-chain thioalkoxy, substituted or substituted C3-C 20 Branched alkyl, substituted or substituted C3-C 20 Branched alkoxy, substituted or substituted C3-C 20 Branched thioalkoxy, substituted or substituted C3-C 20 Cycloalkyl, substituted or substituted C3-C 20 Cyclic alkoxy groups, substituted or substituted C3-C 20 Cyclic thioalkoxy, substituted or substituted silyl groups, substituted or substituted C1-C 20 Ketone group, substituted or substituted C2-C 20 alkoxycarbonyl, substituted or substituted C7-C 20 aryloxycarbonyl, C3~C 20 alkenyl, C3~C 20 Alynyl, aryl with 5 to 30 substituted or unsubstituted ring atoms, heteroaryl with 5 to 30 substituted or unsubstituted ring atoms, aryloxy with 5 to 30 substituted or unsubstituted ring atoms, heteroaryloxy with 5 to 30 substituted or unsubstituted ring atoms, or combinations of these groups.

[0045] The substituents include halogen, hydroxyl, carboxyl, nitro, amino, cyano, isocyanate, silyl, C1-C1 groups. 20 Alkyl, C1-C 20 Alkoxy, C1-C 20 Alkylthio, C1-C 20 Ketone group, C1-C 20 One or more of the following: amino group, aryl group with 5 to 30 ring atoms, aryloxy group with 5 to 30 ring atoms, and arylthio group with 5 to 30 ring atoms.

[0046] The quantum dot surface of the nanomaterial described in this application is connected with the compound containing disulfide bonds and the thiol compound. On the one hand, the compound containing disulfide bonds and the thiol compound can effectively passivate defects on the quantum dot surface, improving the stability and fluorescence quantum efficiency of the quantum dots. On the other hand, the compound containing disulfide bonds and the thiol compound can undergo the following reversible dynamic reaction:

[0047]

[0048] Based on the dynamic exchange reaction between the thiol compound and the compound containing disulfide bond (i.e., the thiol-disulfide bond dynamic exchange reaction), the disulfide bond can be reduced to two thiol groups, and the thiol groups can be re-oxidized to disulfide bonds. Based on this reversible dynamic property, the quantum dot has a self-healing function, which enables the first ligand and the second ligand to be stably coordinated and connected to the surface of the quantum dot, effectively avoiding the phenomenon of ligand detachment, migration, and degradation on the surface of the quantum dot.

[0049] When quantum dot inks or films containing the aforementioned nanomaterials encounter chemical or physical damage, such as chemical damage from water, oxygen, or light exposure, or physical damage from friction or bending, a self-healing mechanism (i.e., a dynamic exchange reaction) can respond rapidly, restoring the integrity and function of the quantum dot ink or film without external intervention. This self-healing property is crucial for improving the long-term reliability and lifespan of quantum dot inks and films. This unique thiol-disulfide bond dynamic exchange reaction significantly enhances the stability of quantum dot inks and films in practical applications.

[0050] In some embodiments, R1, R2, and R3 are each independently including, but not limited to, C3 to C3 substituted or site-substituted. 15 Straight-chain alkyl, substituted or substituted C3-C 15 Straight-chain alkoxy, substituted or substituted C3-C 15 Straight-chain thioalkoxy, substituted or substituted C3-C 15Branched alkyl, substituted or substituted C3-C 15 Branched alkoxy, substituted or substituted C3-C 15 Branched thioalkoxy, substituted or substituted C3-C 15 Cycloalkyl, substituted or substituted C3-C 15 Cyclic alkoxy groups, substituted or substituted C3-C 15 Cyclic thioalkoxy, substituted or substituted silyl groups, substituted or substituted C1-C 15 Ketone group, substituted or substituted C2-C 150 alkoxycarbonyl, substituted or substituted C7-C 15 aryloxycarbonyl, C3~C 20 alkenyl, C3~C 15 Alkyne, aryl group having 5 to 20 substituted or unsubstituted ring atoms, heteroaryl group having 5 to 20 substituted or unsubstituted ring atoms, aryloxy group having 5 to 20 substituted or unsubstituted ring atoms, heteroaryloxy group having 5 to 20 substituted or unsubstituted ring atoms, or combinations of these groups.

[0051] Furthermore, in some embodiments, R1, R2, and R3 are each independently, including but not limited to, substituted or site-substituted C3-C 10 Straight-chain alkyl, substituted or substituted C3-C 10 Straight-chain alkoxy, substituted or substituted C3-C 15 Straight-chain thioalkoxy, substituted or substituted C3-C 10 Branched alkyl, substituted or substituted C3-C 10 Branched alkoxy, substituted or substituted C3-C 10 Branched thioalkoxy, substituted or substituted C3-C 10 Cycloalkyl, substituted or substituted C3-C 10 Cyclic alkoxy groups, substituted or substituted C3-C 10 Cyclic thioalkoxy, substituted or substituted silyl groups, substituted or substituted C1-C 10 Ketone group, substituted or substituted C2-C 10 alkoxycarbonyl, substituted or substituted C7-C 10 aryloxycarbonyl, C3~C 15 alkenyl, C3~C 10 Alkyne, aryl group having 5 to 15 substituted or unsubstituted ring atoms, heteroaryl group having 5 to 15 substituted or unsubstituted ring atoms, aryloxy group having 5 to 15 substituted or unsubstituted ring atoms, heteroaryloxy group having 5 to 15 substituted or unsubstituted ring atoms, or combinations of these groups.

[0052] Furthermore, in some embodiments, R1, R2, and R3 each independently include, but are not limited to, substituted or substituted C3-C8 straight-chain alkyl groups, substituted or substituted C3-C8 straight-chain alkoxy groups, substituted or substituted C3-C8 straight-chain thioalkoxy groups, substituted or substituted C3-C8 branched alkyl groups, substituted or substituted C3-C8 branched alkoxy groups, substituted or substituted C3-C8 branched thioalkoxy groups, substituted or substituted C3-C8 cyclic alkyl groups, substituted or substituted C3-C8 cyclic alkoxy groups, substituted or substituted C3-C8 cyclic thioalkoxy groups, substituted or substituted silyl groups, substituted or substituted C1-C8 ketone groups, substituted or substituted C2-C8 alkoxycarbonyl groups, and substituted or substituted C7-C8 cyclic alkoxycarbonyl groups. 10 Aryloxycarbonyl, C3-C8 alkenyl, C3-C8 alkynyl, aryl with 5 to 10 substituted or unsubstituted ring atoms, heteroaryl with 5 to 10 substituted or unsubstituted ring atoms, aryloxy with 5 to 10 substituted or unsubstituted ring atoms, heteroaryloxy with 5 to 10 substituted or unsubstituted ring atoms, or combinations of these groups.

[0053] As an example, in some embodiments, the disulfide-containing compounds include, but are not limited to, one or more of dipropyl disulfide (CAS: 629-19-6), 6,6'-dithionyldimethylbis(hexane-1-ol) (CAS: 80901-86-6), 3,3'-dihydrooxolinenic acid (CAS: 1119-62-6), dibenzyl disulfide (CAS: 150-60-7), homocysteine, 3,3'-difluorodiphenyl disulfide (CAS: 63930-17-6), and bis(p-chlorobenzyl) disulfide (CAS: 23566-17-8).

[0054] The structural formula of the dipropyl disulfide is:

[0055]

[0056] The chemical structural formula of the 6,6'-dithiodiylbis(hexane-1-ol) is as follows:

[0057]

[0058] The chemical structural formula of the 3,3'-dihydrooxoline acid is as follows:

[0059]

[0060] The chemical structural formula of the dibenzyl disulfide is:

[0061]

[0062] The chemical structural formula of the homocysteine ​​is:

[0063]

[0064] The chemical structural formula of the 3,3'-difluorodiphenyl disulfide is:

[0065]

[0066] The chemical structural formula of the bis(p-chlorobenzyl) disulfide is:

[0067]

[0068] As an example, in some embodiments, the thiol compounds include, but are not limited to, one or more of the following: butanethiol (CAS: 109-79-5), 1,6-hexanedithiol (CAS: 1191-43-1), cyclohexanethiol (CAS: 1569-69-3), 1,9-nonanedithiol (CAS: 3489-28-9), 11-mercaptoundecanoic acid (CAS: 71310-21-9), 3-mercapto-2-benzylpropylglycine (CAS: 76721-89-6), and p-fluorobenzylthiophenol (CAS: 371-42-6).

[0069] The chemical structural formula of the butanethiol is:

[0070]

[0071] The chemical structural formula of the 1,6-hexanedithiol is:

[0072]

[0073] The chemical structural formula of the cyclohexanethiol is:

[0074]

[0075] The chemical structural formula of the 1,9-nonanedithiol is:

[0076]

[0077] The chemical structural formula of the 11-mercaptoundecanoic acid is as follows:

[0078]

[0079] The chemical structural formula of the 3-mercapto-2-benzylpropylglycine is as follows:

[0080]

[0081] The chemical structural formula of the p-fluorothiophenol is as follows:

[0082]

[0083] The quantum dots may include, but are not limited to, one or more of the following: single-structure quantum dots, core-shell structure quantum dots, and perovskite quantum dots. The core-shell structure quantum dots may have one or more shell layers.

[0084] The materials for the single-structure quantum dots, the core materials for the core-shell structure quantum dots, and the shell materials for the core-shell structure quantum dots may include, but are not limited to, one or more of group II-VI compounds, group IV-VI compounds, group III-V compounds, and group I-III-VI compounds. The group II-VI compounds may include, but are not limited to, one or more 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 may include, but are not limited to, one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe. The group III-V compounds may include, but are not limited to, one or more 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 group I-III-VI compounds may include, but are not limited to, one or more of CuInS2, CuInSe2, and AgInS2.

[0085] As an example, the core-shell structured quantum dots may include, but are not limited to, one or more of CdSe / 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.

[0086] The perovskite quantum dots may include, but are not limited to, doped or undoped inorganic perovskite quantum dots, or organic-inorganic hybrid perovskite quantum dots. The general structural formula of the inorganic perovskite quantum dots is AMX3, where A is Cs. + Ions, where M is a divalent metal cation, including Pb 2+ Sn 2+ Cu 2+ Ni 2+ Cd 2+ Cr 2+ Mn 2+ Co 2+ Fe 2+ 、Ge 2+ Yb 2+ Eu 2+ One or more of them, where X is a halide anion, including Cl. - ,Br - I - One or more of the following. The general structural formula of the organic-inorganic hybrid perovskite quantum dots is BMX3, where B is an organic amine cation, including CH3(CH2). n-2 NH3 + Or [NH3(CH2)] n NH3] 2+ Where n≥2, M is a divalent metal cation, including Pb 2+ Sn 2+ Cu 2+ Ni 2+ Cd 2+ Cr 2+ Mn 2+ Co 2+ Fe 2+ 、Ge 2+ Yb 2 + Eu 2+ One or more of them, where X is a halide anion, including Cl. - ,Br - I - One or more of them.

[0087] In some embodiments, the average particle size of the quantum dots ranges from 5 to 20 nm, for example, 5 nm, 10 nm, 15 nm, 20 nm, etc.

[0088] In some embodiments, the surface of the quantum dot further includes organic ligands, including but not limited to substituted or unsubstituted C6-C. 24 Fatty acids, substituted or unsubstituted C6-C 24 Fatty amines, substituted or unsubstituted C6-C 24 Aliphatic thiols, substituted or unsubstituted C6-C 24 Aliphatic sulfides, substituted or unsubstituted C6-C 24 Aliphatic phosphine, substituted or unsubstituted C6-C 24 Aliphatic phosphine oxides, substituted or unsubstituted C8-C8 phosphine oxides 20 Aliphatic phosphates, substituted or unsubstituted C6-C 24 Aliphatic phosphates, substituted or unsubstituted C6-C 24 Aliphatic phosphorous acid and substituted or unsubstituted C6-C 24 At least one of the fatty phosphites, wherein the substituent is selected from at least one of C1-C6 alkyl, C1-C6 alkoxy and halogen.

[0089] In some embodiments, the substituted or unsubstituted C6-C 24 Fatty acids include at least one of the following: decanoic acid, undecenoic acid, tetradecanoic acid, oleic acid, linoleic acid, and stearic acid.

[0090] In some embodiments, the substituted or unsubstituted C6-C 24 Aliphatic thiols include at least one of octylthiol, dodecylthiol, and octadecylthiol.

[0091] In some embodiments, the substituted or unsubstituted C6-C 24 Fatty amines include at least one of oleylamine, octadecylamine, octylamine, dioctylamine, and trioctylamine.

[0092] In some embodiments, the substituted or unsubstituted C6-C 24 Aliphatic phosphines include trioctylphosphine.

[0093] In some embodiments, the substituted or unsubstituted C6-C 24 Aliphatic phosphine oxides include trioctylphosphine oxides.

[0094] In some embodiments, the molar ratio of the first ligand to the second ligand is 1:(0.5–5), for example, 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, etc. Within this ratio range, defects on the surface of the quantum dots can be effectively passivated, and the nanomaterials can also have good self-healing capabilities, thereby giving the nanomaterials high stability.

[0095] In some embodiments, the mass ratio of the second ligand to the quantum dot is (1–10):1, for example, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, etc. Within this range, defects on the surface of the quantum dot can be effectively passivated, and the nanomaterial can have good conductivity, which is beneficial for carrier injection into the interior of the quantum dot, giving the quantum dot a high fluorescence quantum efficiency.

[0096] Secondly, this application also provides a quantum dot ink, which includes the nanomaterials and solvents described above.

[0097] The nanomaterials mentioned above will not be repeated here.

[0098] The solvents include, but are not limited to, one or more of the following: n-octane, isooctane, n-hexane, cyclohexane, ethyl acetate, benzene, toluene, chloroform, carbon tetrachloride, dichloromethane, dimethyl ether, and tetraethylene glycol dimethyl ether.

[0099] In some embodiments, the concentration of the nanomaterial in the quantum dot ink ranges from 5 to 100 mg / mL, for example, 5 mg / mL, 10 mg / mL, 20 mg / mL, 30 mg / mL, 40 mg / mL, 50 mg / mL, 60 mg / mL, 70 mg / mL, 80 mg / mL, 90 mg / mL, 100 mg / mL, etc. This concentration range is suitable for processes such as spin coating, blade coating, and inkjet printing, and is beneficial for preparing films with a thickness of 10–60 nm.

[0100] The quantum dot ink described in this application includes the nanomaterials mentioned above. When the quantum dot ink or the film prepared from the quantum dot ink encounters chemical or physical damage, such as chemical damage caused by water and oxygen or light exposure, or physical damage caused by vibration, the self-repair mechanism can respond quickly and restore the integrity and function of the nanomaterials without external intervention. This self-repair characteristic is crucial for improving the long-term reliability and service life of quantum dot ink.

[0101] In addition to its self-healing properties, the dynamic exchange reaction of thiol-disulfide bonds endows quantum dot inks with shear-thinning rheological properties, thereby improving the ink's processing performance. When external shear force is applied, the dynamic covalent bonds in quantum dot inks can break rapidly and reduce the crosslinking density, leading to a decrease in viscosity and making the quantum dot ink easier to flow and process. Simultaneously, this shear-thinning behavior facilitates the precise shaping of quantum dot inks in printing, coating, and other processing processes. Under static conditions without shear force, these dynamic bonds reform, allowing the quantum dot ink to regain its original viscosity and shape, exhibiting excellent structural stability. Furthermore, the thiol-disulfide exchange reaction facilitates the orientation process of molecular chains, as the breaking and reforming of dynamic covalent bonds makes it easier for molecular chains to rearrange, thus macroscopically manifesting shear-thinning behavior.

[0102] In some embodiments, the quantum dot ink is further provided with additives, including but not limited to one or more of organophosphorus and organic amines. The organophosphorus includes, but is not limited to, one or more of tri-n-butylphosphine (TBP), triphenylphosphine (PPh3), trimethylphosphine (PMe3), and dimethylphenylphosphine (DMPP). The organic amines include, but are not limited to, one or more of diisopropylethylamine (DIPEA) and tetramethylethylenediamine (TMEDA).

[0103] The additives can effectively promote the dynamic exchange reaction of thiol-disulfide bonds in the quantum dot ink, which is beneficial to improving the stability and fluorescence quantum efficiency of the nanomaterials. Specifically, the organophosphorus can form an ion-pair intermediate between organophosphorus cations and thiol anions, with the thiol anion then attacking the disulfide bond to complete the dynamic exchange reaction. The organic amine can promote the deprotonation of thiols, facilitating the formation of thiol anions, thereby indirectly promoting the thiol-disulfide bond exchange reaction.

[0104] As an example, tri-n-butylphosphine can form an ion-pair intermediate between a tri-n-butylphosphine cation and a thiol anion. The thiol anion then attacks the disulfide bond to complete the exchange, improving the stability of quantum dot inks. Triphenylphosphine, similar to tri-n-butylphosphine, possesses strong nucleophilicity and reducing properties, allowing it to form adducts with thiol anions, thereby promoting the thiol-disulfide bond exchange reaction. Trimethylphosphine, as a smaller phosphine ligand, exhibits even higher nucleophilicity, enabling it to form adducts with thiols more effectively. Dimethylphenylphosphine combines the properties of phosphine and aromatic compounds, maintaining sufficient nucleophilicity to promote thiol-disulfide bond exchange while also possessing good stability due to its aromaticity. The use of DMPP can also bring new physical properties, such as improved solubility or processability of materials.

[0105] In some embodiments, the mass ratio of the additive to the nanomaterial is (0.01–0.2):1, for example, 0.01:1, 0.02:1, 0.03:1, 0.05:1, 0.06:1, 0.08:1, 0.1:1, 0.12:1, 0.13:1, 0.15:1, 0.16:1, 0.18:1, 0.2:1, etc. Within this range, the quantum dot ink can exhibit high stability.

[0106] Thirdly, please refer to Figure 1 This application also provides a method for preparing quantum dot ink, comprising the following steps:

[0107] Step S11: Provide a quantum dot solution, the quantum dot solution comprising quantum dots and a solvent, and mix the quantum dot solution with a compound containing disulfide bonds and a thiol compound to obtain a mixture;

[0108] Step S12: Heat the mixture to coordinate the disulfide-bonded compound and the thiol compound to the surface of the quantum dots, thereby obtaining quantum dot ink.

[0109] The quantum dot ink prepared by the method includes a solvent and nanomaterials. The nanomaterials include quantum dots, a first ligand coordinated with the quantum dots, and a second ligand coordinated with the quantum dots. The first ligand is a compound containing disulfide bonds, and the second ligand is a thiol compound.

[0110] The quantum dots, the disulfide-bonded compounds, the thiols, and the solvents are described above and will not be repeated here.

[0111] Understandably, in some embodiments, the quantum dot solution may be the quantum dot stock solution obtained from synthesizing quantum dots.

[0112] In some embodiments, the molar ratio of the thiol compound to the disulfide-containing compound is (0.5–5):1. Within this range, it is advantageous to prepare a composite material with good stability and high fluorescence quantum efficiency.

[0113] In some embodiments, the mass ratio of the thiol compound to the quantum dots is (1–20):1, for example, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1, 20:1, etc. Within this range, it is advantageous to prepare composite materials with good stability and high fluorescence quantum efficiency.

[0114] In some embodiments, the heating temperature is 25°C to 120°C, for example, 25°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, etc.; the heating time is 10 to 60 minutes, for example, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes, 60 minutes, etc. Within the temperature and time range, it is beneficial for the disulfide-bonded compound and the thiol compound to be fully and effectively coordinated and connected to the surface of the quantum dots, which is beneficial for preparing quantum dot inks with good stability and fluorescence quantum efficiency.

[0115] In some embodiments, the process further includes adding an additive after heating the mixture and before obtaining the quantum dot ink.

[0116] The additives mentioned above will not be repeated here.

[0117] In some embodiments, the mass ratio of the additive to the nanomaterial is (0.01–0.2):1, for example, 0.01:1, 0.02:1, 0.03:1, 0.05:1, 0.06:1, 0.08:1, 0.1:1, 0.12:1, 0.13:1, 0.15:1, 0.16:1, 0.18:1, 0.2:1, etc. Within this range, the prepared quantum dot ink can exhibit high stability and fluorescence quantum efficiency.

[0118] Understandably, in some embodiments, the nanomaterials described in this application are prepared by drying the quantum dot ink.

[0119] Understandably, during the drying process, the additive will detach with the solvent and will not be present in the nanomaterial.

[0120] In some embodiments, the process further includes washing and purification after heating the mixture and before obtaining the quantum dot ink, followed by redissolving it in a solvent. This is beneficial for obtaining quantum dot ink with higher purity.

[0121] The washing and purification process uses detergents known for washing quantum dot inks during preparation, such as organic solvents like ethanol.

[0122] Understandably, the addition of the additive is carried out after washing and purification, so as to avoid the additive being washed away.

[0123] Fourthly, embodiments of this application also provide a quantum dot film, wherein the quantum dot film includes the nanomaterial, or the quantum dot film is prepared from the quantum dot ink through a film-forming process.

[0124] The thickness of the quantum dot film is 10–60 nm.

[0125] Fifthly, please refer to Figure 2 This application provides a light-emitting device 100, comprising an anode 10, a light-emitting layer 20, and a cathode 30 stacked sequentially. The light-emitting layer 20 includes the aforementioned nanomaterials, or the light-emitting layer 20 is prepared from the quantum dot ink through a film-forming process.

[0126] In some embodiments, the light-emitting device 100 further includes an electron transport layer 40 located between the light-emitting layer 20 and the cathode 30.

[0127] In some embodiments, the light-emitting device 100 further includes a hole transport layer 50 located between the anode 10 and the light-emitting layer 20.

[0128] The anode 10 and the cathode 30 are anodes and cathodes known in the art for use in light-emitting devices. For example, they can be independently, but are not limited to, doped metal oxide particle electrodes, composite electrodes, graphene electrodes, carbon nanotube electrodes, elemental metal electrodes, or alloy electrodes. The material of the doped metal oxide particle electrode can be, but is not limited to, one or more of indium-doped tin oxide (ITO), fluorine-doped tin oxide (FTO), antimony-doped tin oxide (ATO), aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), indium-doped zinc oxide (IZO), magnesium-doped zinc oxide (MZO), and aluminum-doped magnesium oxide (AMO). The composite electrode is a composite electrode in which a metal is sandwiched between doped or undoped transparent metal oxide particles, such as 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, ZnS / Al / ZnS, etc., where " / " indicates a stacked structure. For example, AZO / Ag / AZO represents a composite electrode comprising sequentially stacked AZO, Ag, and AZO layers. The material of the elemental metal electrode may include, but is not limited to, one or more of Ag, Al, Cu, Mo, Au, Pt, Ca, Mg, and Ba.

[0129] The material of the electron transport layer 40 is a material known in the art for use in electron transport layers, such as one or more selected from, but not limited to, inorganic and organic electron transport materials. The inorganic electron transport material includes, but is not limited to, one or more of the following: first doped metal oxide particles, first undoped metal oxide particles, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The material of the first undoped metal oxide particles includes, but is not limited to, one or more of ZnO, TiO2, SnO2, ZrO2, and Ta2O5. The metal oxide in the first doped metal oxide particles includes, but is not limited to, one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, and Al2O3. The doping element in the first doped metal oxide particles includes, but is not limited to, one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, and Ga. The IIB-VIA group semiconductor materials include, but are not limited to, one or more of ZnS, ZnSe, and CdS. The IIIA-VA group semiconductor materials include, but are not limited to, one or more of InP and GaP. The IB-IIIA-VIA group semiconductor materials include, but are not limited to, one or more of CuInS and CuGaS. The organic electron transport material includes one or more of the following: quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, and hydroxyquinoline compounds.

[0130] The material of the hole transport layer 50 can also be any material known in the art for hole transport layers, such as, but not limited to, one or more of inorganic hole transport materials and organic hole transport materials. The inorganic hole transport material includes, but is not limited to, one or more of second-doped metal oxide particles, second-undoped metal oxide particles, metal sulfides, metal selenides, and metal nitrides. The metal oxides in the second-doped metal oxide particles and the metal oxides in the second-undoped metal oxide particles each independently include, but are not limited to, one or more of MoO3, WO3, NiO, CrO3, CuO, Cu2O, and V2O5. The doping elements in the second-doped metal oxide particles include, but are not limited to, one or more of Mo, W, Ni, Cr, Cu, and V. The metal sulfides include, but are not limited to, one or more of CuS, MoS3, and WS3. The metal selenides include, but are not limited to, one or more of MoSe3 and WSe3. The metal nitrides include, but are not limited to, p-type gallium nitride.The organic hole transport materials include, but are not limited to, 4,4'-N,N'-dicarbazolyl-biphenyl (CBP), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4”-diamine (α-NPD), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), poly(N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)biphenylamine) (Poly-TPD), N,N'- Bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro(spiro-TPD), N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine (DNTPD), 4,4',4'-tris(N-carbazolyl)-triphenylamine (TCTA), 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine (m-MTDATA), poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))](TFB), poly(N-vinylcarbazole)(PVK) ) and its derivatives, N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4-4'-diamine (NPB), spiroNPB, poly(phenylenevinylene) (PPV), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (MOMO-PPV), 2,2',7,7'-tetra[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene (spiro-omeT) AD), 4,4'-cyclohexylbis[N,N-di(4-methylphenyl)aniline] (TAPC), 1,3-bis(carbazole-9-yl)benzene (MCP), polyaniline, polypyrrole, poly(p-)phenylenevinylene, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazole)-1,1'-biphenyl compounds, N,N,N',N'-tetraarylbenzidine, PEDOT:PSS and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, doped graphene, undoped graphene, and one or more of C60.

[0131] In some embodiments, the light-emitting device 100 further includes a hole injection layer. The material of the hole injection layer can be a material known in the art for hole injection layers, such as, but not limited to, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazabenzphenanthrene (HAT-CN), PEDOT, PEDOT:PSS, a derivative of PEDOT:PSS doped with s-MoO3 (PEDOT:PSS:s-MoO3), 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine (m-MTDATA), tetracyanoquinone dimethyl ether (F4-TCQN), copper phthalocyanine, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, molybdenum sulfide, tungsten sulfide, and copper oxide.

[0132] In some embodiments, the thickness of the anode 10 is 10–200 nm; the thickness of the light-emitting layer 20 is 10–60 nm; the thickness of the cathode 30 is 30–100 nm; the thickness of the electron transport layer 40 is 20–60 nm; and the thickness of the hole transport layer 50 is 20–100 nm.

[0133] It is understood that the light-emitting device 100 may also be provided with some functional layers that are conventionally used in light-emitting devices and help to improve the performance of the light-emitting device, such as electron blocking layer, hole blocking layer, electron injection layer, interface modification layer, etc.

[0134] It is understood that the materials of each layer of the light-emitting device 100 can be adjusted according to the light-emitting requirements of the light-emitting device 100.

[0135] In some embodiments, the light-emitting device 100 further includes a substrate disposed on the side of the anode 10 away from the light-emitting layer 20, or the substrate disposed on the side of the cathode 30 away from the light-emitting layer 20.

[0136] The substrate can be a rigid substrate or a flexible substrate. In some embodiments, the substrate material may include, but is not limited to, one or more of glass, silicon wafer, polycarbonate, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, polyamide, and polyethersulfone.

[0137] It is understood that the light-emitting device 100 can be a normally positioned light-emitting device or an inverted light-emitting device. The light-emitting device 100 can be a quantum dot light-emitting device or an organic light-emitting device.

[0138] Sixthly, embodiments of this application also provide a display device, the display device including the light-emitting device 100.

[0139] The display device can be any electronic product with display function, including but not limited to smartphones, tablets, laptops, digital cameras, digital camcorders, smart wearable devices, smart weighing scales, in-vehicle displays, televisions, or e-book readers. Among them, smart wearable devices can be, for example, smart bracelets, smartwatches, virtual reality (VR) headsets, etc.

[0140] The present application will be specifically described below through specific embodiments. The following embodiments are only some embodiments of the present application and are not intended to limit the present application.

[0141] Ink Example 1

[0142] Step 1: Zinc acetate (7 mmol) and oleic acid (7 mL) are placed in a 50 mL flask and evacuated at 120 °C for one hour. Then, the environment is switched to an argon atmosphere. Subsequently, 15 mL of 1-octadecene is added to obtain a mixture, and the temperature of the mixture is raised to 300 °C. The first Se-TOP solution and cadmium oleate solution are rapidly injected into the mixture. The first Se-TOP solution is obtained by dissolving 0.8 mmol of Se powder in 0.4 mL of trioctylphosphine (TOP) and cadmium oleate is obtained by dissolving 0.16 mmol of cadmium oleate in 0.6 mL of oleic acid to obtain a quantum dot core solution, which includes quantum dot cores ZnCdSe.

[0143] Step 2: Add the first S-TOP solution to the quantum dot core solution at a rate of 0.025 mL / min. The second S-TOP solution is obtained by dissolving 0.8 mmol Se powder in 0.4 mL TOP, and the first S-TOP solution is obtained by dissolving 0.2 mmol S powder in 0.1 mL TOP. React for 30 minutes. Simultaneously add the second S-TOP solution and Cd solution at a rate of 0.04 mL / min. The second S-TOP solution is obtained by dissolving 0.8 mmol S powder in 0.4 mL TOP, and the Cd solution is obtained by dissolving 0.32 mmol cadmium oleate in 0.4 mL TOP. Grow a CdSeS shell on the surface of the quantum dot core to form ZnCdSe / CdSeS blue quantum dots, obtaining the quantum dot stock solution.

[0144] Step 3: Dissolve the thiol compound 1,6-hexanedithiol and the disulfide-containing compound dipropyldisulfide in ethanol to obtain a ligand solution, wherein the molar ratio of the thiol compound to the disulfide-containing compound is 2:1; add the ligand solution to the quantum dot stock solution, wherein the mass ratio of the thiol compound in the ligand solution to the quantum dots in the quantum dot stock solution is 10:1; react at 60°C for 30 min to form thiol compound ligands and disulfide-containing compound ligands on the surface of the ZnCdSe / CdSeS blue quantum dots, thereby obtaining a nanomaterial solution;

[0145] Step 4: Cool to ambient temperature, then wash and purify with ethanol, and redissolve in isooctane to obtain quantum dot ink.

[0146] The quantum dot ink of this embodiment includes nanomaterials and isooctane (solvent), wherein the nanomaterials include ZnCdSe / CdSeS blue quantum dots and 1,6-hexanedithiol and dipropyldisulfide coordinated to the surface of the quantum dots.

[0147] Ink Example 2

[0148] This embodiment is basically the same as ink embodiment 1, except that the thiol compound 1,9-nonanedithiol is used in this embodiment to replace 1,6-hexanedithiol in ink embodiment 1.

[0149] Ink Example 3

[0150] This embodiment is basically the same as ink embodiment 1, except that the thiol compound 3-mercapto-2-benzylpropylglycine is used in this embodiment to replace 1,6-hexanedithiol in ink embodiment 1.

[0151] Ink Example 4

[0152] This embodiment is basically the same as ink embodiment 1, except that in this embodiment, the dipropyl disulfide in ink embodiment 1 is replaced by 3,3'-dihydrooxylinic acid, a compound containing disulfide bonds.

[0153] Ink Example 5

[0154] This embodiment is basically the same as ink embodiment 1, except that this embodiment uses a compound containing disulfide bonds, bis(p-chlorobenzyl) disulfide, to replace dipropyl disulfide in ink embodiment 1.

[0155] Ink Example 6

[0156] This embodiment is basically the same as ink embodiment 1, except that the molar ratio of the thiol compound to the compound containing disulfide bonds in this embodiment is 0.5:1.

[0157] Ink Example 7

[0158] This embodiment is basically the same as ink embodiment 1, except that the molar ratio of the thiol compound to the compound containing disulfide bonds in this embodiment is 5:1.

[0159] Ink Example 8

[0160] This embodiment is basically the same as ink embodiment 1, except that the mass ratio of the thiol compound in the ligand solution to the quantum dots in the quantum dot stock solution is 1:1.

[0161] Ink Example 9

[0162] This embodiment is basically the same as ink embodiment 1, except that the mass ratio of the thiol compound in the ligand solution to the quantum dots in the quantum dot stock solution is 20:1.

[0163] Ink Example 10

[0164] This embodiment is basically the same as ink embodiment 1, except that the reaction temperature in step S3 of this embodiment is 25°C.

[0165] Ink Example 11

[0166] This embodiment is basically the same as ink embodiment 1, except that the reaction temperature in step S3 of this embodiment is 120°C.

[0167] Ink Example 12

[0168] This embodiment is basically the same as ink embodiment 1, except that cadmium-free quantum dots ZnSeTe are used in this embodiment to replace the ZnCdSe / CdSeS quantum dots in embodiment 1.

[0169] Ink Example 13

[0170] This embodiment is basically the same as ink embodiment 1, except that after obtaining the nanomaterial solution, this embodiment also includes adding the additive TBP to the nanomaterial solution, wherein the mass ratio of the additive to the nanomaterial is 0.1:1.

[0171] The ink in this example includes ZnCdSe / CdSeS blue quantum dots, additive TBP, and dipropyl disulfide and 1,6-hexanedithiol coordinated to the surface of the quantum dots.

[0172] Ink Example 14

[0173] This embodiment is basically the same as ink embodiment 13, except that in this embodiment, DIPEA is used to replace TBP in ink embodiment 13.

[0174] Ink Example 15

[0175] This embodiment is basically the same as ink embodiment 13, except that the mass ratio of the additive to the nanomaterial in this embodiment is 0.01:1.

[0176] Ink Example 16

[0177] This embodiment is basically the same as ink embodiment 13, except that the mass ratio of the additive to the nanomaterial in this embodiment is 0.2:1.

[0178] Ink Comparison Example 1

[0179] This comparative example is basically the same as ink example 1, except that the preparation of quantum dot ink in this comparative example does not include step S3, and the quantum dot surface of the quantum dot ink prepared in this comparative example is not connected with compounds containing disulfide bonds and thiols.

[0180] Ink Comparison Example 2

[0181] This comparative example is basically the same as ink example 1, except that step S3 of this comparative example does not use thiol compounds, and the quantum dot ink prepared in this comparative example has ligands containing disulfide bonds on the surface of the quantum dots, but no thiol compound ligands.

[0182] Ink Comparison Example 3

[0183] This comparative example is basically the same as ink example 1, except that step S3 of this comparative example does not use compounds containing disulfide bonds, and the quantum dot ink prepared in this comparative example has ligands containing thiol compounds attached to the surface of the quantum dots, but no ligands containing disulfide bonds attached.

[0184] Ink Comparison Example 4

[0185] This comparative example is basically the same as ink comparative example 1, except that ZnSeTe quantum dots are used to replace ZnCdSe / CdSeS quantum dots in example 1 in this comparative example.

[0186] The quantum dot inks of Ink Examples 1-16 and Ink Comparative Examples 1-4 were stored in a room temperature, humid (relative humidity of 50%), natural light and air environment. A small amount of ink was taken every 2 weeks to observe the changes in DLS particle size and precipitation of quantum dot ink over time. The observation results are shown in Table 1.

[0187] The quantum dot inks of Ink Examples 1-16 and Ink Comparative Examples 1-4 were stored in a room temperature, dry, light-protected, and nitrogen-filled environment. A small amount of ink was taken every two weeks to observe the changes in DLS particle size and precipitation of the quantum dot ink over time. The observation results are shown in Table 1.

[0188] The DLS particle size measurement method is as follows: Principle: DLS (Dynamic Light Scattering) technology is based on the phenomenon of light scattering. When a laser beam shines on sample particles, the particles scatter the light, forming scattered light. This scattered light contains information about the particles, such as particle size and particle size distribution. By analyzing the intensity fluctuations of the scattered light, the particle size can be calculated. The steps include: adding the sample to be tested to a suitable solvent and suspending it uniformly; adjusting the instrument parameters, such as laser power, detection angle, and measurement time, according to the properties and particle size range of the sample to obtain a suitable scattered light signal; placing the sample in the measurement cell and measuring the sample using the instrument's built-in probe or adapter. During this process, the instrument automatically generates an intensity-time curve; and calculating the particle size and analyzing the particle size distribution based on the characteristics of the curve.

[0189] Table 1:

[0190]

[0191]

[0192] As shown in Table 1:

[0193] Compared to the quantum dot inks in Comparative Examples 1-4, the quantum dot inks in Examples 1-16 showed no change in DLS particle size and no precipitation during storage and placement in room temperature, dry, light-proof, and nitrogen environments. This indicates that the nanomaterials described in this application have high stability and are not prone to agglomeration in inks. The reason may be that when the nanomaterials described in this application are damaged, their self-repair mechanism can respond quickly and restore their integrity and function without external intervention, exhibiting excellent structural stability.

[0194] Compared to the quantum dot inks of Comparative Examples 1-4, the quantum dot inks of Examples 1-16 showed no change in DLS particle size and no precipitation during storage and placement in room temperature, dry, light-proof, and nitrogen environments. However, when stored under water, oxygen, and light conditions, the quantum dot inks of Examples 1-16 showed less or no change in DLS particle size and no precipitation during placement, compared to the quantum dot inks of Comparative Examples 1-4. This may be because the quantum dot inks of Examples 1-16 contain the nanomaterials described above. When the quantum dot ink or the film prepared from the quantum dot ink is damaged, the self-repair mechanism can respond quickly and restore the integrity and function of the nanomaterials without external intervention.

[0195] Thin films with a thickness of 50 nm were prepared using the quantum dot inks of Ink Examples 1-16 and Ink Comparative Examples 1-4, respectively. The initial fluorescence quantum efficiency (PLQY) of the films was tested, as well as the fluorescence quantum efficiency (PLQY) after 3 days in a room temperature, dry, light-proof, and nitrogen environment, and the fluorescence quantum efficiency (PLQY) after 3 days of storage in a room temperature, 50% relative humidity, natural light, and air environment. The test results are shown in Table 2.

[0196] Thin films with a thickness of 50 nm were prepared using quantum dot inks from Ink Examples 1-16 and Ink Comparative Examples 1-4, respectively. The initial surface roughness (surface roughness before friction) and the surface roughness after rubbing once with a rubber glove and then standing for 24 hours were tested. The test results are shown in Table 2.

[0197] The fluorescence quantum yield (PLQY) was tested using a steady-state fluorescence spectrometer from Edinburgh Instruments, model FS5, with the SC-30 accessory for measuring the fluorescence quantum yield.

[0198] Table 2:

[0199]

[0200]

[0201] As shown in Table 2:

[0202] Compared to the films prepared with quantum dot inks in Examples 1-4, the films prepared with quantum dot inks in Examples 1-16 still exhibit high PLQY after being placed in a room temperature, dry, light-protected, and nitrogen-filled environment. They also maintain high PLQY after being placed in water, oxygen, and light conditions, as well as after chemical damage. The surface roughness changes less after physical damage. This may be because the films prepared with inks in Examples 1-16 include the nanomaterials described above. When the films encounter chemical or physical damage, the self-repair mechanism can respond quickly and restore the integrity and function of the nanomaterials without external intervention.

[0203] Device Example 1

[0204] Provide an ITO anode 10 glass substrate, wipe the ITO surface with a cotton swab dipped in a small amount of soapy water to remove visible impurities, then ultrasonically clean it with deionized water, acetone, ethanol, and isopropanol for 15 minutes, and then dry it with nitrogen gas for later use.

[0205] A TFB material with a concentration of 10 mg / mL was spin-coated onto the anode 10 at a spin speed of 2500 rpm for 40 seconds, followed by annealing at 200°C for 30 min to obtain a hole transport layer 50 with a thickness of 40 nm.

[0206] The quantum dot ink from Example 1 was spin-coated onto the hole transport layer 50 at a spin speed of 1500 rpm for 30 seconds, followed by annealing at 100°C for 5 minutes to obtain a light-emitting layer 20 with a thickness of 30 nm.

[0207] An ethanol solution of ZnO with a concentration of 40 mg / mL was spin-coated onto the light-emitting layer 20 at a speed of 3000 rpm for 60 seconds, followed by annealing at 100°C for 5 min to obtain an electron transport layer 40 with a thickness of 25 nm.

[0208] In a vacuum coating machine, thermal evaporation is performed, with a vacuum level not exceeding 3×10⁻⁶. -4 Pa, evaporate Ag to form an Ag layer with a thickness of 100 nm, to obtain cathode 30;

[0209] The light-emitting device 100 is obtained by packaging.

[0210] Device Examples 2-16

[0211] Device Examples 2 to 16 are basically the same as Device Example 1, except that Device Examples 2 to 16 use quantum dot ink from Ink Examples 2 to 16 to replace the quantum dot ink from Quantum Dot Example 1.

[0212] Device Comparison Examples 1-4

[0213] The devices in Comparative Examples 1 to 4 are basically the same as those in Device Example 1, except that the quantum dot ink in Comparative Examples 1 to 4 is replaced with the quantum dot ink in Quantum Dot Example 1.

[0214] The external quantum efficiency (EQE), lifetime (T95), and lifetime (T95@1000 nit) of the light-emitting devices in Device Examples 1-16 and Device Comparative Examples 1-4 were tested. The test results are shown in Table 3.

[0215] External quantum efficiency (EQE) is the ratio of electron-hole pairs injected into a quantum dot to emitted photons, expressed as a percentage (%). It is an important parameter for evaluating the quality of electroluminescent devices and can be measured using an EQE optical testing instrument. The specific calculation formula is as follows:

[0216]

[0217] Where ηe is the optical output coupling efficiency, ηr is the ratio of the number of recombinated carriers to the number of injected carriers, χ is the ratio of the number of excitons that generate photons to the total number of excitons, KR is the radiative process rate, and KNR is the non-radiative process rate.

[0218] The lifetime T95 and lifetime T95@1000nit test methods are as follows: In CDA gas, under constant current or voltage drive, the time it takes for the device brightness to decay to a certain percentage of its maximum brightness is measured. The time for the brightness to decay to 95% of the maximum brightness is defined as T95, and this lifetime is the measured lifetime. To shorten the lifetime testing cycle, device lifetime testing is usually performed at high brightness by accelerating device aging, and the lifetime at low brightness is obtained by fitting a decay fitting formula. For example, the lifetime at 1000 nits is denoted as T95@1000nits, and the calculation formula is:

[0219]

[0220] Among them, T95 L The lifespan at low brightness is typically taken as the lifespan at 1000 nits, T95. H The lifetime at high brightness, i.e., the measured lifetime, L H L is the maximum brightness that the device accelerates to. L The typical value is 1000 nits, where A is the acceleration factor, taken as 1.7. The constant current is 2 mA.

[0221] EQE and lifespan testing conditions: conducted at room temperature with 50% humidity.

[0222] Table 3:

[0223]

[0224]

[0225] As shown in Table 3:

[0226] Compared to the light-emitting devices in Comparative Examples 1-3, the light-emitting devices in Examples 1-11 and 13-16 exhibit higher external quantum efficiency and longer lifetime. Compared to the light-emitting device in Comparative Example 4, the light-emitting device in Example 12 exhibits higher external quantum efficiency and longer lifetime. It is evident that light-emitting devices using the nanomaterials of this application as the light-emitting layer material or those prepared using the quantum dot inks of this application can possess higher external quantum efficiency and longer lifetime. This may be because the quantum dot surface of the nanomaterials described in this application is connected to the disulfide-bonded compound and the thiol compound. On one hand, the disulfide-bonded compound and the thiol compound can effectively passivate defects on the quantum dot surface, improving the stability of the quantum dots. On the one hand, the fluorescence quantum efficiency is high; on the other hand, a reversible dynamic reaction can occur between the compound containing disulfide bonds and the thiol compound. Based on this dynamic exchange reaction (i.e., thiol-disulfide bond dynamic exchange reaction), the disulfide bond can be reduced to two thiol groups, and the thiol groups can be re-oxidized to disulfide bonds. Based on this reversible dynamic property, the quantum dots have a self-healing function, which enables the first ligand and the second ligand to be stably coordinated and connected to the surface of the quantum dots. This can effectively avoid the shedding, migration, and degradation of ligands on the surface of the quantum dots. When the light-emitting layer including the nanomaterial is damaged, the self-healing mechanism (i.e., dynamic exchange reaction) can respond quickly and restore the integrity and function of the light-emitting layer without external intervention.

[0227] The technical solutions provided by the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A nanomaterial, characterized in that, The nanomaterial comprises quantum dots, a first ligand and a second ligand, the first ligand is a compound containing a disulfide bond, and the second ligand is a thiol compound.

2. The nanomaterial of claim 1, wherein, The nanomaterial is composed of the quantum dots, the first ligand and the second ligand.

3. The nanomaterial according to any one of claims 1-2, wherein, The compound containing a disulfide bond has a structural formula as shown in the following formula (I): The thiol compound has a structural formula as shown in the following formula (II): R3-OH (II) wherein R1, R2, R3 each independently include substituted or unsubstituted C3-C 20 linear alkyl, substituted or unsubstituted C3-C 20 linear alkoxy, substituted or unsubstituted C3-C 20 linear thioalkoxy, substituted or unsubstituted C3-C 20 branched alkyl, substituted or unsubstituted C3-C 20 branched alkoxy, substituted or unsubstituted C3-C 20 branched thioalkoxy, substituted or unsubstituted C3-C 20 cyclic alkyl, substituted or unsubstituted C3-C 20 cyclic alkoxy, substituted or unsubstituted C3-C 20 cyclic thioalkoxy, substituted or unsubstituted silyl, substituted or unsubstituted C1-C 20 keto, substituted or unsubstituted C2-C 20 alkoxycarbonyl, substituted or unsubstituted C7-C 20 aryloxycarbonyl, C3-C 20 alkenyl, C3-C 20 alkynyl, substituted or unsubstituted aryl having 5 to 30 ring atoms, substituted or unsubstituted heteroaryl having 5 to 30 ring atoms, substituted or unsubstituted aryloxy having 5 to 30 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 30 ring atoms, or a combination of these groups; The substituents include halogen, hydroxyl, carboxyl, nitro, amino, cyano, isocyanate, silyl, C1-C1 groups. 20 Alkyl, C1-C 20 Alkoxy, C1-C 20 Alkylthio, C1-C 20 Ketone group, C1-C 20 One or more of the following: amino group, aryl group with 5 to 30 ring atoms, aryloxy group with 5 to 30 ring atoms, and arylthio group with 5 to 30 ring atoms.

4. The nanomaterial of claim 3, wherein, Further comprising at least one of the following features (1)-(3): (1) R1, R2, R3each independently include substituted or unsubstituted C3to C 15 linear alkyl, substituted or unsubstituted C3to C 15 linear alkoxy, substituted or unsubstituted C3to C 15 linear thioalkoxy, substituted or unsubstituted C3to C 15 branched alkyl, substituted or unsubstituted C3to C 15 branched alkoxy, substituted or unsubstituted C3to C 15 branched thioalkoxy, substituted or unsubstituted C3to C 15 cyclic alkyl, substituted or unsubstituted C3to C 15 cyclic alkoxy, substituted or unsubstituted C3to C 15 cyclic thioalkoxy, substituted or unsubstituted silyl, substituted or unsubstituted C1to C 15 keto, substituted or unsubstituted C2to C 150 alkoxycarbonyl, substituted or unsubstituted C7to C 15 aryloxycarbonyl, C3to C 20 alkenyl, C3to C 15 alkynyl, substituted or unsubstituted aryl having 5 to 20 ring atoms, substituted or unsubstituted heteroaryl having 5 to 20 ring atoms, substituted or unsubstituted aryloxy having 5 to 20 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 20 ring atoms, or a combination of these groups; (2) R1, R2, R3 each independently include substituted or unsubstituted C3-C 10 straight-chain alkyl, substituted or unsubstituted C3-C 10 straight-chain alkoxy, substituted or unsubstituted C3-C 15 straight-chain thioalkoxy, substituted or unsubstituted C3-C 10 branched alkyl, substituted or unsubstituted C3-C 10 branched alkoxy, substituted or unsubstituted C3-C 10 branched thioalkoxy, substituted or unsubstituted C3-C 10 cyclic alkyl, substituted or unsubstituted C3-C 10 cyclic alkoxy, substituted or unsubstituted C3-C 10 cyclic thioalkoxy, substituted or unsubstituted silyl, substituted or unsubstituted C1-C 10 keto, substituted or unsubstituted C2-C 10 alkoxycarbonyl, substituted or unsubstituted C7-C 10 aryloxycarbonyl, C3-C 15 alkenyl, C3-C 10 alkynyl, substituted or unsubstituted aryl having 5 to 15 ring atoms, substituted or unsubstituted heteroaryl having 5 to 15 ring atoms, substituted or unsubstituted aryloxy having 5 to 15 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 15 ring atoms, or a combination of these groups; (3) R1, R2, R3each independently include substituted or unsubstituted C3-C8 straight chain alkyl, substituted or unsubstituted C3-C8 straight chain alkoxy, substituted or unsubstituted C3-C8 straight chain thioalkoxy, substituted or unsubstituted C3-C8 branched chain alkyl, substituted or unsubstituted C3-C8 branched chain alkoxy, substituted or unsubstituted C3-C8 branched chain thioalkoxy, substituted or unsubstituted C3-C8 cyclic alkyl, substituted or unsubstituted C3-C8 cyclic alkoxy, substituted or unsubstituted C3-C8 cyclic thioalkoxy, substituted or unsubstituted silyl group, substituted or unsubstituted C1-C8 keto group, substituted or unsubstituted C2-C8 alkoxycarbonyl group, substituted or unsubstituted C7-C 10 substituted or unsubstituted C3-C8 alkenyl group, substituted or unsubstituted C3-C8 alkynyl group, substituted or unsubstituted aryl group having 5 to 10 ring atoms, substituted or unsubstituted heteroaryl group having 5 to 10 ring atoms, substituted or unsubstituted aryloxy group having 5 to 10 ring atoms, substituted or unsubstituted heteroaryloxy group having 5 to 10 ring atoms, or a combination of these groups.

5. The nanomaterial according to any one of claims 1-2, wherein, The molar ratio of the first ligand to the second ligand is 1:(0.5-5); and / or The mass ratio of the second ligand to the quantum dots is (1-10):1; and / or The first ligand is coordinately connected with the quantum dots; and / or The second ligand is coordinately connected with the quantum dots; and / or The compound containing a disulfide bond comprises one or more of dipropyl disulfide, 6,6'-dithia- bis(hexan-1-ol), 3,3'-dihydroxyphenyl acid, dibenzyl disulfide, homocystine, 3,3'-difluorobenzene disulfide, bis(p-chlorobenzyl) disulfide; and / or The thiol compound comprises one or more of butanethiol, 1,6-hexanedithiol, cyclohexanethiol, 1,9-nonanedithiol, 11-mercaptoundecanoic acid, 3-mercapto-2-benzylpropyl glycine, p-fluorophenylthiol; and / or The average particle size of the quantum dots ranges from 5 to 20 nm; and / or The quantum dots include one or more of single-structure quantum dots, core-shell quantum dots including one or more shell layers, and perovskite semiconductor materials, the material of the single-structure quantum dots, the core material of the core-shell quantum dots, and the shell layer material of the core-shell quantum dots are independently selected from one or more of II-VI compounds, IV-VI compounds, III-V compounds, and I-III-VI compounds, the II-VI compounds include one or more 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 compounds include one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, the III-V compounds include one or more 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 compounds include one or more of CuInS2, CuInSe2, and AgInS2, the perovskite semiconductor materials include doped or non-doped inorganic perovskite semiconductors or organic-inorganic hybrid perovskite semiconductors, the inorganic perovskite semiconductors have a general structure of AMX3, where A is a Cs + ion, M is a divalent metal cation including Pb 2+ , Sn 2+ , Cu 2+ , Ni 2+ , Cd 2+ , Cr 2+ , Mn 2+ , Co 2+ , Fe 2+ , Ge 2+ , Yb 2+ , Eu 2+ one or more of Cl - , Br - , I - ; the structure general formula of the organic-inorganic hybrid perovskite type semiconductor is BMX3, wherein B is an organic amine cation, including CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , wherein n≥2, M is a divalent metal cation, including one or more of Pb 2+ , Sn 2+ , Cu 2+ , Ni 2+ , Cd 2+ , Cr 2+ , Mn 2+ , Co 2+ , Fe 2+ , Ge 2+ , Yb 2+ , Eu 2+ one or more of Cl - , Br - , I - .

6. Ink, characterized by The ink further comprises a solvent and the nanomaterial according to any one of claims 1-5.

7. The ink according to claim 6, wherein Further comprising at least one of the following features (1)-(3): (1) The solvent comprises one or more of n-octane, isooctane, n-hexane, cyclohexane, ethyl acetate, benzene, toluene, chloroform, carbon tetrachloride, dichloromethane, dimethyl ether, tetraethylene glycol dimethyl ether; (2) In the ink, the concentration of the nanomaterial ranges from 5 to 100 mg / mL; (3) The ink further comprises an additive, wherein: The additive comprises one or more of an organic phosphine and an organic amine, the organic phosphine comprises one or more of tri-n-butyl phosphine, triphenyl phosphine, trimethyl phosphine, dimethyl phenyl phosphine, the organic amine comprises one or more of diisopropyl ethyl amine, tetramethyl ethylenediamine; and / or The mass ratio of the additive to the nanomaterial is (0.01-0.2):

1.

8. A method for preparing an ink, characterized by, The method comprises the following steps: Providing a quantum dot solution comprising quantum dots and a solvent, mixing the quantum dot solution with a compound containing a disulfide bond and a thiol compound to obtain a mixture; Heating the mixture to obtain an ink, the ink comprising a solvent and a nanomaterial, the nanomaterial comprising quantum dots, a first ligand coordinately connected with the quantum dots, and a second ligand coordinately connected with the quantum dots, the first ligand being a compound containing a disulfide bond, and the second ligand being a thiol compound.

9. The production method according to claim 8, wherein Further comprising at least one of the following features (1)-(6): (1) the molar ratio of the thiol compound to the disulfide bond-containing compound is (0.5-5):1; (2) the mass ratio of the thiol compound to the quantum dots is (1-20):1; (3) the heating temperature is 25-120°C, and the heating time is 10-60 min; (4) the solvent comprises one or more of n-octane, iso-octane, n-hexane, cyclohexane, ethyl acetate, benzene, toluene, chloroform, carbon tetrachloride, dichloromethane, dimethyl ether, tetraethylene glycol dimethyl ether; (5) the disulfide bond-containing compound has the following structural formula (I): the thiol compound has the following structural formula (II): R3-OH (II) wherein R1, R2, R3 each independently include substituted or unsubstituted C3-C 20 straight-chain alkyl, substituted or unsubstituted C3-C 20 straight-chain alkoxy, substituted or unsubstituted C3-C 20 straight-chain thioalkoxy, substituted or unsubstituted C3-C 20 branched alkyl, substituted or unsubstituted C3-C 20 branched alkoxy, substituted or unsubstituted C3-C 20 branched thioalkoxy, substituted or unsubstituted C3-C 20 cyclic alkyl, substituted or unsubstituted C3-C 20 cyclic alkoxy, substituted or unsubstituted C3-C 20 cyclic thioalkoxy, substituted or unsubstituted silyl, substituted or unsubstituted C1-C 20 keto, substituted or unsubstituted C2-C 20 alkoxycarbonyl, substituted or unsubstituted C7-C 20 aryloxycarbonyl, C3-C 20 alkenyl, C3-C 20 alkynyl, substituted or unsubstituted aryl having 5 to 30 ring atoms, substituted or unsubstituted heteroaryl having 5 to 30 ring atoms, substituted or unsubstituted aryloxy having 5 to 30 ring atoms, substituted or unsubstituted heteroaryloxy having 5 to 30 ring atoms, or a combination of these groups; The substituents include halogen, hydroxyl, carboxyl, nitro, amino, cyano, isocyanate, silyl, C1-C1 groups. 20 Alkyl, C1-C 20 Alkoxy, C1-C 20 Alkylthio, C1-C 20 Ketone group, C1-C 20 One or more of the following: amino group, aryl group with 5 to 30 ring atoms, aryloxy group with 5 to 30 ring atoms, and arylthio group with 5 to 30 ring atoms; (6) after heating the mixture and before obtaining the ink, further comprising adding an additive, wherein: the additive comprises one or more of an organic phosphine and an organic amine, the organic phosphine comprises one or more of tri-n-butyl phosphine, triphenyl phosphine, trimethyl phosphine, dimethyl phenyl phosphine, the organic amine comprises one or more of diisopropyl ethyl amine, tetramethyl ethylene diamine; the mass ratio of the additive to the nanomaterial is (0.01-0.2):

1.

10. A film, characterized by, The thin film comprises the nanomaterial according to any one of claims 1-5, or the thin film is prepared by a film-forming process using the ink according to any one of claims 6-7.

11. A light-emitting device, characterized in that, The light-emitting layer comprises the nanomaterial according to any one of claims 1-5, or the light-emitting layer is prepared by a film-forming process using the ink according to any one of claims 6-7.

12. The light-emitting device according to claim 11, wherein: the anode and the cathode each independently comprises a doped metal oxide particle electrode, a composite electrode, a graphene electrode, a carbon nanotube electrode, a metal element electrode or an alloy electrode, the material of the doped metal oxide particle electrode comprises one or more of indium-doped tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, indium-doped zinc oxide, magnesium-doped zinc oxide and aluminum-doped magnesium oxide, the composite electrode comprises one or more 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 or ZnS / Al / ZnS, the material of the metal element electrode comprises one or more of Ag, Al, Cu, Mo, Au, Pt, Ca, Mg and Ba; and / or The light-emitting device further comprises an electron transport layer between the light-emitting layer and the cathode, the material of the electron transport layer is selected from one or more of inorganic electron transport materials and organic electron transport materials, the inorganic electron transport materials include one or more of first doped metal oxide particles, first non-doped metal oxide particles, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials and IB-IIIA-VIA group semiconductor materials, the material of the first non-doped metal oxide particles includes one or more of ZnO, TiO2, SnO2, ZrO2 and Ta2O5, the metal oxide in the first doped metal oxide particles includes one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5 and Al2O3, the doping element in the first doped metal oxide particles includes one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In and Ga, the IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe and CdS, the IIIA-VA group semiconductor materials include one or more of InP and GaP, the IB-IIIA-VIA group semiconductor materials include one or more of CuInS and CuGaS; the organic electron transport materials include one or more of quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds and hydroxyquinoline compounds; and / or The light-emitting device further includes a hole transport layer between the anode and the light-emitting layer, a material of the hole transport layer including one or more of an inorganic hole transport material and an organic hole transport material, the inorganic hole transport material including one or more of second doped metal oxide particles, second undoped metal oxide particles, metal sulfide, metal selenide, and metal nitride, the metal oxide in the second doped metal oxide particles and the metal oxide in the second undoped metal oxide particles each independently including one or more of MoO3, WO3, NiO, CrO3, CuO, Cu2O, V2O5, the doping element in the second doped metal oxide particles including one or more of Mo, W, Ni, Cr, Cu, V, the metal sulfide including one or more of CuS, MoS3, WS3, the metal selenide including one or more of MoSe3, WSe3, the metal nitride including P-type gallium nitride;The organic hole transport material includes one or more of 4,4'-N,N'-dicarbazolyl-biphenyl, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, poly(N,N'bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine), N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-di(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tris(N-carbazolyl)-triphenylamine, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-buty lphenyl)benzidine)], poly(N-vinylcarbazole) and derivatives thereof, N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4-4'-diamine, Spiro NPB, poly(phenylenevinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene], 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene, 4,4'-cyclohexylbis[N,N-di(4-methylphenyl)benzidine], 1,3-bis(carbazol-9-yl)benzene, polyaniline, polypyrrole, poly(p-phenylenevinylene), aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT:PSS and derivatives thereof, polymethacrylate and derivatives thereof, poly(9,9-octylfluorene) and derivatives thereof, poly(spirofluorene) and derivatives thereof, doped graphene, non-doped graphene, one or more of C60.

13. A display device comprising: The light-emitting device comprises the light-emitting device according to any one of claims 11-12.

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