Nano material, preparation method and photoelectric device

Abstract

The invention discloses a nano material, a preparation method and a photoelectric device, and relates to the technical field of display. The preparation method of the nano material comprises the following steps: providing a core solution, wherein the core solution comprises a quantum dot core and a first solvent; a shell source is provided, the shell source comprises a zinc sulfide precursor, the structural formula of the zinc sulfide precursor is shown as a formula (I): # imgabs0 #, the shell source is injected into the core solution, a reaction is conducted, and the nanometer material is obtained. According to the preparation method of the nano material provided by the invention, when the prepared nano material is used for preparing a thin film, the roughness of the thin film can be improved, and the thin film with high density and stability is obtained.

Description

Technical Field

[0001] The present application relates to the field of display technologies, and in particular, to a nanomaterial, a preparation method thereof, and an optoelectronic device. Background Art

[0002] Currently, the widely used optoelectronic devices are organic light-emitting diodes (OLEDs) and quantum dot light-emitting diodes (QLEDs). Due to its excellent display performance such as self-luminescence, simple structure, ultra-thinness, fast response speed, wide viewing angle, low power consumption, and flexible display, OLED has become the mainstream technology in the field of display technologies. QLED has the advantages of saturated emission light color and adjustable wavelength, and high photoluminescence and electroluminescence quantum yields. In recent years, it has become a strong competitor of OLED.

[0003] In recent years, the performance of QLED devices has made great progress, basically meeting the minimum standards for commercial use. However, the stability of quantum dot film formation is still a major challenge. Poor stability will cause large fluctuations in device performance, seriously affecting the mass production of QLEDs.

[0004] When preparing a thin film from quantum dots prepared by existing preparation methods, the film formation roughness of the quantum dot film is relatively high, resulting in relatively serious leakage current and affecting the optoelectronic efficiency of the optoelectronic device. Summary of the Invention

[0005] In view of this, the present application provides a nanomaterial, a preparation method thereof, and an optoelectronic device.

[0006] The embodiment of the present application is implemented as follows. A preparation method of a nanomaterial includes:

[0007] Providing a core solution, where the core solution includes quantum dot cores and a first solvent;

[0008] Providing a shell source, where the shell source includes a zinc sulfide precursor, and the structural formula of the zinc sulfide precursor is shown in formula (I):

[0009]

[0010] Wherein, R1 and R2 are each independently selected from hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, one or more of substituted or unsubstituted heterocyclic groups having 3 to 20 ring atoms; R3, R4, R5, R6, R7 each independently include hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, one or more of substituted or unsubstituted heterocyclic groups having 3 to 20 ring atoms; the heteroatoms in the heteroalkyl, heteroalkenyl, heteroalkynyl, and heterocyclic groups include one or more of N, S, O, P, and Si; the substituents of the substituted groups each independently include -NH, -F, -Cl, -Br, -I, -OH, -COOH, -NO, -SO H, -CHO, -SH, -OH, -OOCCH3, -CN, etc.;

[0011] Inject the shell source into the core solution and react to obtain the nanomaterial.

[0012] Correspondingly, the embodiments of the present application further provide a nanomaterial prepared by the above preparation method, or the nanomaterial includes quantum dots and a first ligand connected to the surface of the quantum dots, and the structural formula of the first ligand is shown in formula (Ⅱ):

[0013]

[0014] Among them, R1 and R2 are each independently selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C32 heterovinyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, one or more of substituted or unsubstituted heterocyclic groups having 3 to 20 ring atoms;

[0015] R3, R4, R5, R6, R7 each independently include hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heterovinyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, one or more of substituted or unsubstituted heterocyclic groups having 3 to 20 ring atoms;

[0016] The heteroatoms in the heteroalkyl, heterovinyl, heteroalkynyl, and heterocyclic groups include one or more of N, S, O, P, and Si;

[0017] The substituents of the substituted groups each independently include one or more of -NH, -F, -Cl, -Br, -I, -OH, -COOH, -NO, -SOH, -CHO, -SH, -OH, -OOCCH3, and -CN.

[0018] Correspondingly, an embodiment of the present application further provides an optoelectronic device, including a first electrode, a light-emitting layer, and a second electrode stacked in sequence. The material of the light-emitting layer includes the nanomaterial prepared by the above preparation method, or the material of the light-emitting layer includes the above nanomaterial.

[0019] The preparation method of the nanomaterial provided by the present application can improve the roughness of the film and obtain a film with high density and stability when preparing a film from the prepared nanomaterial. Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present 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 the present application. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 It is a flowchart of the preparation method of the nanomaterial provided by the embodiment of the present application;

[0022] Figure 2 It is a schematic structural diagram of the optoelectronic device provided by the embodiment of the present application;

[0023] Figure 3 It is a schematic structural diagram of another optoelectronic device provided by the embodiment of the present application;

[0024] Figure 4 It is an AFM image of the light-emitting layer of Device Example 1 of the present application;

[0025] Figure 5 It is an AFM image of the light-emitting layer of Comparative Example 1 of the device of the present application;

[0026] Figure 6 It is a voltage-current density curve graph of Device Example 1 and Comparative Example 1 of the device of the present application.

[0027] Reference Signs:

[0028] Light-emitting layer 10; First electrode 20; Second electrode 30; First carrier functional layer 40; Second carrier functional layer 50. Detailed Embodiments

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0030] In this application, unless otherwise stated, the orientation terms such as "upper" and "lower" generally refer to the upper and lower in the actual use or working state of the device, specifically the drawing direction in the attached drawings; while "inner" and "outer" refer to the outline of the device. Additionally, in the description of this application, the term "comprising" means "including but not limited to". The terms first, second, third, etc. are only used as labels and do not impose numerical requirements or establish an order.

[0031] In this application, "and / or" describes the association relationship of associated objects and indicates that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Where A and B can be singular or plural.

[0032] In this application, "at least one" means one or more, and "a plurality" means two or more. "One or several", "at least one (item) below" or similar expressions refer to any combination of these items, including any combination of single (item) or plural items. For example, "at least one (item) of a, b, or c", or, "at least one (item) 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 be single or multiple respectively.

[0033] The various embodiments of this application can 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 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, and this applies 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.

[0034] In the prior art, octanethiol is often used as a ligand for quantum dots to improve the performance of quantum dots. However, during the addition of octanethiol, a large amount of octanethiol is often used in the synthesis of the ZnS shell, resulting in too few octanethiol ligands in the prepared quantum dots and being unable to effectively improve the performance of the quantum dots.

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

[0036] In a first aspect, please refer to Figure 1 , an embodiment of this application provides a method for preparing a nanomaterial, including:

[0037] S11. Provide a nuclear solution, where the nuclear solution includes a quantum dot core and a first solvent;

[0038] S12. Provide a shell source, where the shell source includes a zinc sulfide precursor, and the structural formula of the zinc sulfide precursor is shown in Formula (Ⅰ):

[0039]

[0040] Among them, R1 and R2 are each independently selected from hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, substituted or unsubstituted heterocyclic group with 3 to 20 ring atoms, or one or more of them; the heteroatoms in the heteroalkyl, heteroalkenyl, and heteroalkynyl include one or more of N, S, O, P, and Si; R3, R4, R5, R6, and R7 each independently include hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20one or more of aryl, or substituted or unsubstituted heterocyclic groups having 3 to 20 ring atoms; the heteroatoms in the heteroalkyl, heteroalkenyl, heteroalkynyl, and heterocyclic groups include one or more of N, S, O, P, and Si; the substituents of the substitution are each independently selected from the group consisting of -NH, -F, -Cl, -Br, -I, -OH, -COOH, -NO, -SOH, -CHO, -SH, -OH, -OOCCH3, and -CN;

[0041] S13. Inject the shell source into the nuclear solution, and react to obtain the nanomaterial.

[0042] In the preparation method of the nanomaterial provided by this application, the zinc sulfide precursor contains sulfur atoms and can be used to synthesize the quantum dot shell layer. The chain lengths of R1 and R2 can be adjusted, and the ligand environment of the quantum dots can be flexibly adjusted. This preparation method is simple and convenient. When preparing a thin film from the obtained nanomaterial, the roughness of the thin film can be improved, and a thin film with high density and stability can be obtained.

[0043] In the step S11:

[0044] In some embodiments, the preparation method of the quantum dot core includes: providing a first metal source, a first anion source, and a second solvent, and reacting to obtain the quantum dot core.

[0045] In some embodiments, the first metal source includes one or more of a cadmium source, a zinc source, a mercury source, a tin source, a lead source, a gallium source, an antimony source, an aluminum source, an indium source, and a copper source.

[0046] In some embodiments, the first anion source includes one or more of a sulfur source, a selenium source, a tellurium source, a nitrogen source, an arsenic source, and a phosphorus source.

[0047] In some embodiments, the first solvent and the second solvent each independently include one or more of oleylamine (OA), diphenylphosphine (DPP), tri-n-octylphosphine (TOP), tri-n-octylphosphine oxide (TOPO), tributyl phosphate (TBP), octyldecanoin (ODE), and diethylpropylphenol (DEPP).

[0048] For example, zinc and cadmium can react with oleylamine to form zinc oleate (Zn(OA)2) and cadmium oleate (Zn(Cd)2) as the zinc source and cadmium source respectively. Selenium powder can be dissolved in diphenylphosphine to obtain Se-DPP as the selenium source.

[0049] In some embodiments, the reaction temperature of the first metal source and the first anion source is 300°C to 350°C, and can be, for example, 310°C, 320°C, 330°C, 340°C, etc.

[0050] In some embodiments, the reaction time of the first metal source and the first anion source is 1 h to 4 h, and for example, it can be 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, etc.

[0051] The preparation of the quantum dot core can be carried out in a protective atmosphere of an inert gas.

[0052] In some embodiments, after the reaction of the first metal source and the first anion source, adding a second anion source is further included.

[0053] In some embodiments, the second anion source includes one or more of a sulfur source, a selenium source, a tellurium source, a nitrogen source, an arsenic source, and a phosphorus source.

[0054] In some embodiments, the solvent in the second anion source includes one or more of tri-n-octylphosphine (TOP), diphenylphosphine (DPP), tri-n-octylphosphine oxide (TOPO), tributyl phosphate (TBP), glyceryl octanoate (ODE), and diethylpropylphenol (DEPP).

[0055] In some embodiments, the time for adding the second anion source is 1 h to 3 h, and for example, it can be 1.5 h, 2 h, 2.5 h, etc.

[0056] In the S12:

[0057] In some embodiments, R1 and R2 are selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, aldehyde, nitro, substituted or unsubstituted C5-C 20 alkyl, substituted or unsubstituted C5-C 20 heteroalkyl, substituted or unsubstituted C5-C 20 alkenyl, substituted or unsubstituted C5-C 20 heteroalkenyl, substituted or unsubstituted C5-C 20 alkynyl, substituted or unsubstituted C5-C 20 heteroalkynyl, substituted or unsubstituted C5-C 20 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C3-C 20 acyloxy, substituted or unsubstituted C5-C 20 alkoxycarbonyl, substituted or unsubstituted C8-C 20 aryl, substituted or unsubstituted heterocyclic group with 5 to 15 ring atoms, etc.

[0058] In some embodiments, R1 and R2 are selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, aldehyde, nitro, substituted or unsubstituted C 10 -C 15alkyl, substituted or unsubstituted C 10 -C 15 heteroalkyl, substituted or unsubstituted C 10 -C 15 alkenyl, substituted or unsubstituted C 10 -C 15 heteroalkenyl, substituted or unsubstituted C 10 C 15 alkynyl, substituted or unsubstituted C 10 -C 15 heteroalkynyl, substituted or unsubstituted C 10 -C 15 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C5-C 15 acyloxy, substituted or unsubstituted C5-C 15 alkoxycarbonyl, substituted or unsubstituted C 10 -C 15 aryl, one or more of substituted or unsubstituted heterocyclic groups having 10 to 15 ring atoms.

[0059] In some embodiments, R3, R4, R5, R6, R7 are selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, aldehyde, nitro, substituted or unsubstituted C5-C 20 alkyl, substituted or unsubstituted C5-C 20 heteroalkyl, substituted or unsubstituted C5-C 20 alkenyl, substituted or unsubstituted C5-C 20 heteroalkenyl, substituted or unsubstituted C5-C 20 alkynyl, substituted or unsubstituted C5-C 20 heteroalkynyl, substituted or unsubstituted C5-C 20 alkoxy, substituted or unsubstituted C3-C 20 acyloxy, substituted or unsubstituted C5-C 20 alkoxycarbonyl, substituted or unsubstituted C8-C 20 aryl, one or more of substituted or unsubstituted heterocyclic groups having 5 to 15 ring atoms.

[0060] In some embodiments, R3, R4, R5, R6, R7 are selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, aldehyde, nitro, substituted or unsubstituted C 10 -C 15 alkyl, substituted or unsubstituted C 10 -C 15 heteroalkyl, substituted or unsubstituted C 10 -C 15alkenyl, substituted or unsubstituted C 10 -C 15 heteroalkenyl, substituted or unsubstituted C 10 -C 15 alkynyl, substituted or unsubstituted C 10 -C 15 heteroalkynyl, substituted or unsubstituted C 10 -C 15 alkoxy, substituted or unsubstituted C 10 -C 15 acyloxy, substituted or unsubstituted C 10 -C 15 alkoxycarbonyl, substituted or unsubstituted C 10 -C 15 aryl, one or more of substituted or unsubstituted heterocyclic groups having 10 to 15 ring atoms.

[0061] In some embodiments, the halogen includes one or more of fluorine, chlorine, bromine, and iodine.

[0062] The alkyl includes one or more of methyl, ethyl, isopropyl, tert-butyl, and n-octyl.

[0063] The alkenyl includes one or more of vinyl, propenyl, and butenyl.

[0064] The alkynyl includes one or more of ethynyl, propynyl, pentynyl, and heptynyl.

[0065] The alkoxy includes one or more of methoxy, ethoxy, and propoxy.

[0066] The acyloxy includes one or more of formyloxy, acetyloxy, propionyloxy, butyryloxy, octanoyloxy, palmitoyloxy, and stearoyloxy.

[0067] The alkoxycarbonyl includes one or more of methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxycarbonyl, octoxycarbonyl, palmitoxycarbonyl, and stearoxycarbonyl.

[0068] The aryl includes one or more of phenyl, p-tolyl, p-nitrophenyl, o-methoxyphenyl, m-methoxyphenyl, p-methoxyphenyl, and p-nitromethoxyphenyl.

[0069] The substituents of the substitution each independently include one or more of -NH, -F, -Cl, -Br, -I, -OH, -COOH, -NO, -SOH, -CHO, -SH, -OH, -OOCCH3, and -CN.

[0070] In some embodiments, the R1 is selected from C2-C 18alkyl groups.

[0071] In some embodiments, R2 is selected from substituted or unsubstituted C1-C 32 alkoxy groups, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7.

[0072] In some embodiments, R2 is selected from one of -N(C2H5)2, -OC 16 H 33 , -SC 16 H 33 , -NHC 16 H 33 , -P(OC 16 H 33 )2.

[0073] In some embodiments, the zinc sulfide precursor includes

[0074] one of them.

[0075] It should be noted that during the reaction, the three bonds of Zn in the zinc sulfide precursor connected to three sulfur atoms will all break. The S in -SH reacts with Zn to form a ZnS shell layer, and the remaining group acts as a ligand and attaches to the ZnS shell layer to serve as a ligand for the quantum dots. In other words, the zinc sulfide precursor provided in this application can not only serve as a sulfur source and a zinc source, but also serve as a source of ligands.

[0076] It can be understood that the zinc sulfide precursor can react to form ZnS, or other metal sources can be added during the reaction to synthesize a shell material containing sulfur, zinc, and other metal elements.

[0077] In some embodiments, the shell source further includes a second metal source.

[0078] Furthermore, the second metal source includes one or more of a cadmium source and a mercury source.

[0079] In some embodiments, the molar ratio of the zinc sulfide precursor to the second metal source is 5:(4 - 8), for example, it can be 5:5, 5:6, 5:7, etc.

[0080] In S13:

[0081] In some embodiments, the temperature at which the shell source reacts with the core solution is 280°C to 320°C, for example, it can be 290°C, 300°C, 310°C, etc.

[0082] In some embodiments, the reaction time of the shell source and the core solution is 10 min to 60 min, and for example, it can be 20 min, 30 min, 40 min, 50 min, etc.

[0083] It should be noted that the method provided in this application can also synthesize core-shell structure quantum dots with multiple shells. The shells synthesized in this application can be all the shells on the surface of the quantum dots, or the first shell close to the surface of the quantum dots, or the second shell on the surface of the first shell far from the quantum dots, etc. During the preparation of the shell, a zinc sulfide precursor is used for preparation, and a ZnS shell can be obtained. If other metal sources are added, a shell containing sulfur element, zinc element and other metal elements can be obtained.

[0084] In some embodiments, after the reaction of the shell source and the core solution, a thiol ligand is further added to obtain a nanomaterial.

[0085] Further, in some embodiments, the thiol ligand includes one or more of propanethiol, butanethiol, octanethiol, dodecanethiol, benzenethiol, 1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, 1,2-ethanedithiol.

[0086] In some embodiments, after the reaction of the shell source and the core solution, a precipitant is further added to obtain a nanomaterial.

[0087] Further, the precipitant includes one or more of acetone, ethyl acetate, hexane, heptane, octane.

[0088] The temperature for adding the precipitant is 100 °C to 150 °C, and for example, it can be 110 °C, 120 °C, 130 °C, 140 °C, etc.

[0089] In a second aspect, the embodiments of this application further provide a nanomaterial, which is prepared by the above preparation method, or includes quantum dots and a first ligand connected to the surface of the quantum dots. The structural formula of the first ligand is as shown in formula (Ⅱ):

[0090]

[0091] Among them, R1 and R2 are respectively selected from hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32The heteroalkynyl group, substituted or unsubstituted C1-C 32 The alkoxy group, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C1-C 32 The acyloxy group, substituted or unsubstituted C1-C 32 The alkoxycarbonyl group, substituted or unsubstituted C6-C 20 One or more of the aryl group, substituted or unsubstituted heterocyclic group with 3 to 20 ring atoms;

[0092] R3, R4, R5, R6, R7 each independently include hydrogen, deuterium, halogen, cyano group, hydroxyl group, carboxyl group, aldehyde group, nitro group, substituted or unsubstituted C1-C 32 The alkyl group, substituted or unsubstituted C1-C 32 The heteroalkyl group, substituted or unsubstituted C2-C 32 The alkenyl group, substituted or unsubstituted C2-C 32 The heteroalkenyl group, substituted or unsubstituted C2-C 32 The alkynyl group, substituted or unsubstituted C2-C 32 The heteroalkynyl group, substituted or unsubstituted C1-C 32 The alkoxy group, substituted or unsubstituted C1-C 32 The acyloxy group, substituted or unsubstituted C1-C 32 The alkoxycarbonyl group, substituted or unsubstituted C6-C 20 One or more of the aryl group, substituted or unsubstituted heterocyclic group with 3 to 20 ring atoms;

[0093] The heteroatoms in the heteroalkyl group, heteroalkenyl group, heteroalkynyl group, and heterocyclic group include one or more of N, S, O, P, and Si;

[0094] The substituents of the substituted groups each independently include one or more of -NH, -F, -Cl, -Br, -I, -OH, -COOH, -NO, -SOH, -CHO, -SH, -OH, -OOCCH3, and -CN.

[0095] The nanomaterial provided by this application includes quantum dots and a first ligand connected to the surface of the quantum dots. The first ligand has two sulfur atoms and has a strong binding force with the quantum dots, which can improve the stability of the quantum dots; and the chain lengths of R1 and R2 of the ligand can be adjusted, and the ligand environment of the quantum dots can be flexibly adjusted. When using this nanomaterial to prepare a thin film, the roughness of the thin film can be improved, and a thin film with high density and stability can be obtained.

[0096] Regarding the material selection of R1, R2, R3, R4, R5, R6, and R7, refer to the above description and will not be elaborated here.

[0097] In some embodiments, the average particle size of the quantum dots is 10 nm to 12 nm, and for example, it can be 10.5 nm, 11 nm, 11.5 nm, etc.

[0098] In some embodiments, the first ligand includes

[0099] one of the following.

[0100] In some embodiments, the S of the first ligand is covalently bonded to the surface of the quantum dots. It should be noted that only one of the two S atoms may be connected to the quantum dots, or both may be connected to the quantum dots. When S is connected to the quantum dots, the corresponding H atoms will precipitate.

[0101] Exemplarily, when the metal in the outermost layer material of the quantum dots contains M, the structural formula of the ligand connected to the surface of the quantum dots is shown in the following figure:

[0102]

[0103] In some embodiments, the quantum dots include core-shell quantum dots.

[0104] In some embodiments, the shell material of the core-shell quantum dots contains sulfur and zinc elements. It can be understood that the S of the first ligand is connected to the zinc element to firmly connect to the surface of the quantum dots.

[0105] Furthermore, the shell material of the core-shell quantum dots includes one or more of ZnS, ZnSeS, ZnSTe, CdZnS, HgZnS, CdZnSeS, CdZnSTe, HgZnSeS, HgZnSTe.

[0106] In some embodiments, the core layer material of the core-shell quantum dots includes one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds. The II-VI group compounds may be selected from, but 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 be selected from, but 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 III-V group compounds may be selected from, but 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 I-III-VI group compounds may be selected from, but not limited to, one or more of CuInS2, CuInSe2, and AgInS2.

[0107] It can be understood that the core layer material and the shell layer material of the core-shell quantum dots are different.

[0108] As an example, the core-shell quantum dots can be selected from, but not limited to, one or more of InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdZnSe / ZnSe / CdZnS / ZnS, CdS / CdSe / ZnS, CdSe / CdZnSeS / ZnS, and InP / ZnSe / ZnS. In the expressions such as CdSe / ZnS above, the " / " indicates that the material after " / " (as the shell layer) coats the material before " / " (as the core layer).

[0109] In some embodiments, the nanomaterial further includes a second ligand connected to the surface of the quantum dots, and the second ligand includes thiol ligands.

[0110] Further, in some embodiments, the thiol ligands include one or more of propanethiol, butanethiol, octanethiol, dodecanethiol, benzenethiol, 1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, and 1,2-ethanedithiol.

[0111] It can be understood that the nanomaterial may further include other conventional ligands in the art.

[0112] In some embodiments, in the nanomaterial, the mass fraction of the first ligand is 7% - 8%, and for example, it can be 7.2%, 7.4%, 7.6%, 7.8%, etc.

[0113] In some embodiments, in the nanomaterial, the mass fraction of the second ligand is 7% - 8%, and for example, it can be 7.2%, 7.4%, 7.6%, 7.8%, etc.

[0114] In some embodiments, in the nanomaterial, the mass ratio of the first ligand to the second ligand is (7 - 8):(7 - 8), and for example, it can be 7:7.2, 7:7.5, 7:7.8, 7:7, 7.2:7, 7.5:7, 7.8:7, etc.

[0115] In a third aspect, please refer to Figure 2 , an optoelectronic device provided by an embodiment of the present application includes a first electrode 20, a light-emitting layer 10, and a second electrode 30 that are sequentially stacked. The light-emitting layer 10 includes a thin film, and the material of the thin film 11 includes the above-mentioned nanomaterial.

[0116] In some embodiments, the optoelectronic device includes a light-emitting diode.

[0117] In some embodiments, the optoelectronic device is a top-emitting optoelectronic device.

[0118] In some other embodiments, the optoelectronic device is an inverted optoelectronic device.

[0119] In some embodiments, referring to Figure 3 , the optoelectronic device further includes one or more of a first carrier functional layer 40 and a second carrier functional layer 50. The first carrier functional layer 40 is disposed between the first electrode 20 and the light-emitting layer 10, and the second carrier functional layer 50 is disposed between the light-emitting layer 10 and the second electrode 30.

[0120] In some embodiments, the first carrier functional layer 40 is a hole functional layer, and the second carrier functional layer 50 is an electron functional layer. Correspondingly, the first electrode 20 is an anode, and the second electrode 30 is a cathode.

[0121] In some other embodiments, the second carrier functional layer 50 is a hole functional layer, and the first carrier functional layer 40 is an electron functional layer. Correspondingly, the second electrode 30 is an anode, and the first electrode 20 is a cathode.

[0122] Furthermore, the hole functional layer includes one or more of a hole injection layer and a hole transport layer.

[0123] The electron functional layer includes one or more of an electron injection layer and an electron transport layer.

[0124] In some embodiments, the first electrode 20 and the second electrode 30 each independently include one or more of a metal, a carbon material, and a metal oxide; the metal includes one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg; the carbon material includes one or more of graphite, a carbon nanotube, graphene, and carbon fiber; the metal oxide includes a metal oxide electrode or a composite electrode with a metal disposed between doped or undoped transparent metal oxides. The material of the metal oxide electrode includes one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO3, and AMO, and the composite electrode includes one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2. Herein, " / " represents a stacked structure. For example, AZO / Ag / AZO represents a composite electrode including a sequentially stacked AZO layer, an Ag layer, and an AZO layer.

[0125] In some embodiments, the materials of the hole functional layer include 4,4'-N,N'-dicarbazolyl-biphenyl, 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, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tris(N-carbazolyl)-triphenylamine, 4,4',4'-tris(carbazol-9-yl)triphenylamine, trichloroisocyanuric acid, terbium-doped phosphate-based green luminescent material, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylene vinylene), poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS derivatives doped with s-MoO3, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-bis(naphthalen-1-yl)-N,N'-diphenylbenzidine, spiro-NPB, nanocrystalline diamond, microcrystalline cellulose and tetracyanoquinodimethane, doped graphene, undoped graphene, second doped metal oxide particles, second undoped metal oxide particles, metal sulfides, metal selenides and metal nitrides, wherein the metal oxides in the second doped metal oxide particles and the metal oxides in the second undoped metal oxide particles independently include one or more of MoO3, WO3, NiO, CrO3, CuO, Cu2O, V2O5, the doping elements in the second doped metal oxide particles include one or more of Mo, W, Ni, Cr, Cu, V, the metal sulfides include one or more of CuS, MoS3, WS3, the metal selenides include one or more of MoSe3, WSe3, and the metal nitrides include p-type gallium nitride.

[0126] In some embodiments, the material of the electronic functional layer includes one or more of 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 one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5. The metal oxides in the first doped metal oxide particles include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, Al2O3. The doping elements in the first doped metal oxide particles include one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga. The IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, CdS. The IIIA-VA group semiconductor materials include one or more of InP, GaP. The IB-IIIA-VIA group semiconductor materials include one or more of CuInS, CuGaS.

[0127] Fourthly, an embodiment of the present application further provides a display device, and the display device includes the above optoelectronic device.

[0128] The display device can be any electronic product with a display function. The electronic products include but are not limited to smartphones, tablet computers, laptop computers, digital cameras, digital video cameras, smart wearable devices, smart weighing electronic scales, in-vehicle displays, televisions, or e-book readers. Among them, the smart wearable devices can be, for example, smart bracelets, smart watches, virtual reality (VR) helmets, etc.

[0129] The present application will be specifically described below through specific embodiments. The following embodiments are only partial embodiments of the present application and do not limit the present application.

[0130] Embodiment 1

[0131] This embodiment provides a nanomaterial, including core-shell quantum dots, a first ligand, and a second ligand. The material of the core-shell quantum dots includes CdZnSe / ZnSe / ZnS. The second ligand is octanethiol, and the structural formula of the first ligand is as follows:

[0132]

[0133] The preparation method of the nanomaterial is as follows:

[0134] S1. Add 20 mmol of Zn(OA)2 solution into a three-necked flask, evacuate to no bubbles at 150 °C, switch to an argon atmosphere for protection, heat up to 330 °C, inject 1 mmol of Se DPP precursor, and then inject 0.12 mmol of Cd(OA)2 precursor after 1 min. React for 2 h to obtain the CdZnSe core layer;

[0135] S2. Slowly inject 3 mmol of Se TOP into the above reaction system over 2 h to grow the ZnSe shell layer. After the reaction is completed, cool down to 310 °C;

[0136] S3. Provide a zinc sulfide precursor Dissolve it in octadecene to obtain a zinc sulfide precursor solution. Inject 0.5 mmol of the zinc sulfide precursor solution into the reaction system of S2 over 20 min to grow the ZnS shell layer and the first ligand;

[0137] S4. Quickly inject 1 mmol of octanethiol into the above reaction system. After reacting for 5 min, cool down to 120 °C to grow the octanethiol ligand;

[0138] S5. Take 40 mL of n-hexane and 40 mL of ethyl acetate in a centrifuge tube, pour them into the above centrifuge tube, then add 60 mL of ethanol, shake well and centrifuge. The precipitate is the nanomaterial.

[0139] Example 2

[0140] This example is basically the same as Example 1, except that in this example, 0.6 mmol of Cd(OA)2 is also injected when injecting the zinc sulfide precursor solution in S3, and the core-shell quantum dot material is CdZnSe / ZnSe / CdZnS.

[0141] Example 3

[0142] This example is basically the same as Example 1, except that in this example, S4 is replaced with: inject 0.25 mmol of the zinc sulfide precursor solution over 5 min, and then cool down to 120 °C. The core-shell quantum dot material is CdZnSe / ZnSe / CdZnS / ZnS, and the core-shell quantum dots do not contain octanethiol ligands.

[0143] Example 4

[0144] This example is basically the same as Example 3, except that in this example, S3 is replaced with: inject 2 mmol of STOP and 0.6 mmol of Cd(OA)2 to synthesize the CdZnS shell layer. The core-shell quantum dot material is CdZnSe / ZnSe / CdZnS / ZnS, and the core-shell quantum dots do not contain octanethiol ligands.

[0145] Example 5

[0146] This example is basically the same as Example 1, except that in this example, the zinc sulfide precursor in S3 is replaced with The structural formula of the first ligand is

[0147] Example 6

[0148] This example is basically the same as Example 1, except that in this example, Zn(OA)2 is not added in S1, the Se source is replaced with an S source, and the core-shell quantum dot material is CdS / CdSe / ZnS.

[0149] Example 7

[0150] This example is basically the same as Example 1, except that in this example, Zn(OA)2 and Cd(OA)2 are not added in S1, and the metal source is replaced with a tin source.

[0151] Example 8

[0152] This example is basically the same as Example 1, except that in this example, after the reaction in S2 ends, the temperature is lowered to 320 °C, and the synthesis of the ZnS shell layer is carried out at this temperature.

[0153] Example 9

[0154] This example is basically the same as Example 1, except that in this example, after the reaction in S2 ends, the temperature is lowered to 280 °C, and the synthesis of the ZnS shell layer is carried out at this temperature.

[0155] Example 10

[0156] This example is basically the same as Example 1, except that in this example, the time for injecting the zinc sulfide precursor solution in S2 is 60 min.

[0157] Example 11

[0158] This example is basically the same as Example 1, except that in this example, the time for injecting the zinc sulfide precursor solution in S2 is 10 min.

[0159] Comparative Example 1

[0160] This comparative example is basically the same as Example 1, except that in this comparative example, S3 is replaced with the simultaneous injection of 2 mmol of S TOP and 0.6 mmol of zinc stearate.

[0161] Comparative Example 2

[0162] This comparative example is basically the same as Example 1, except that in this comparative example, S3 is replaced by injecting 2 mmol of S TOP and 0.6 mmol of Cd(OA)2 simultaneously.

[0163] Comparative Example 3

[0164] This comparative example is basically the same as Example 1, except that in this comparative example, S3 is replaced by injecting 2 mmol of S TOP, 0.6 mmol of Cd(OA)2 and zinc stearate simultaneously, and after synthesizing CdZnS, S TOP and zinc stearate are injected again to further synthesize the ZnS shell layer.

[0165] Device Example 1

[0166] This device example provides an optoelectronic device, and the preparation method is as follows:

[0167] Provide ITO glass, wipe the ITO surface with a cotton swab dipped in a small amount of soapy water to remove visible impurities on the surface, then ultrasonically clean it with deionized water, acetone, ethanol, and isopropanol for 15 min, then dry it with nitrogen, and irradiate it with UV for 15 min to form the ITO anode;

[0168] Spin-coat PEDOT:PSS on the ITO anode at a rotation speed of 5000 rpm for 30 s, and then heat it at 100 °C for 15 min to form the hole injection layer;

[0169] Dissolve TFB in chlorobenzene at a concentration of 8 mg / mL, spin-coat it on the hole injection layer at a rotation speed of 3000 rpm for 30 s, and then heat it at 100 °C for 15 min to form the hole transport layer;

[0170] Prepare a quantum dot solution from the nanomaterials of Example 1, and set the quantum dot solution on the hole transport layer to obtain the light-emitting layer;

[0171] Spin-coat an ethanol solution of ZnO on the light-emitting layer at a rotation speed of 4000 rpm, and then heat it at 80 °C for 10 min to form the electron transport layer;

[0172] On the electron transport layer, turn on the Ag target, and the Ag target is evaporated at a rate to form the cathode;

[0173] Encapsulate to obtain the optoelectronic device.

[0174] Device Examples 2 - 11

[0175] Device Examples 2 - 11 are basically the same as Device Example 1, except that the nanomaterials of Example 1 are respectively replaced by the nanomaterials of Examples 2 - 11.

[0176] Device Comparative Examples 1-3

[0177] Device Comparative Examples 1-3 are basically the same as Device Example 1, except that the nanomaterials in Example 1 are respectively replaced with the nanomaterials in Comparative Examples 1-3.

[0178] AFM images of the light-emitting layers of Device Examples 1-11 and Device Comparative Examples 1-3 were tested, and the AFM image of the light-emitting layer of Device Example 1 is as Figure 4 shown, and the AFM image of the light-emitting layer of Device Comparative Example 1 is as Figure 5 shown; the roughness of the light-emitting layers of Device Examples 1-11 and Device Comparative Examples 1-3 is shown in Table 1.

[0179] From Figure 4 and Figure 5 and the test data, it can be obtained that the roughness Ra of the light-emitting layer of Device Example 1 is 0.78 nm, while the roughness Ra of the light-emitting layer of Device Comparative Example 1 is 1.65 nm, about twice that of the light-emitting layer of Device Example 1, indicating that the nanomaterials prepared by this scheme are used to prepare the light-emitting layer, which can effectively improve the film-forming performance of the light-emitting layer and improve the density of the light-emitting layer.

[0180] The leakage current conditions of Device Examples 1-11 and Device Comparative Examples 1-3 were tested, and the current densities of the optoelectronic devices of Device Example 1 and Device Comparative Example 1 are as Figure 6 shown, and the leakage currents of the optoelectronic devices of Device Examples 1-11 and Device Comparative Examples 1-3 are shown in Table 1. The leakage current test was measured by an efficiency test system built with Keithley 2400 and Keithley 6485.

[0181] From Figure 6 it can be obtained that the leakage current of Device Example 1 has been significantly improved compared with that of Device Comparative Example 1, because the roughness of the light-emitting layer is reduced and the density is increased, thereby reducing the leakage current phenomenon.

[0182] Table 1

[0183]

[0184]

[0185] As can be seen from Table 1:

[0186] From Device Examples 1-4 and Device Comparative Examples 1-3, it can be obtained that the roughness of the light-emitting layers of Comparative Examples 1-3 is greater than 1.5 nm, and the leakage current is 10 -2 mA / cm 2Around, using the zinc sulfide precursor provided by the present application to prepare the quantum dot shell layer and synthesize ligands is beneficial to reducing the roughness of the light-emitting layer, improving the film-forming property of the light-emitting layer, and thus alleviating the leakage current phenomenon of optoelectronic devices; whether it is synthesizing the first shell layer coating the quantum dot core or the second shell layer coating the first shell layer, the performance of optoelectronic devices can be effectively improved;

[0187] From Device Example 1, Device Examples 5-7 and Comparative Example 1, it can be seen that replacing the core layer material of the quantum dots or replacing the zinc sulfide precursor to prepare the quantum dot shell layer has little impact on the performance between optoelectronic devices, and there are obvious improvement effects compared with Comparative Example 1. This is because the zinc sulfide precursor can flexibly adjust the ligand environment of the quantum dots, improve the roughness of the thin film, and obtain a light-emitting layer with high density and stability;

[0188] From Device Example 1, Device Examples 8-11 and Comparative Example 1, it can be seen that when preparing the quantum dot shell layer and synthesizing ligands using the zinc sulfide precursor, within the temperature and time ranges provided by the present application, the roughness of optoelectronic devices can be effectively improved, the density of the light-emitting layer can be increased, and thus the leakage current phenomenon of optoelectronic devices can be reduced. There is no significant difference in the performance of optoelectronic devices under different time and temperature ranges.

[0189] The above has introduced in detail the nanomaterials, preparation methods, and optoelectronic devices provided by the embodiments of the present application. Specific examples are used in this article to elaborate on the principles and implementation manners of the present application. The descriptions of the above embodiments are 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. A preparation method of a nanomaterial, characterized in that, Comprising: Providing a core solution, which includes a quantum dot core and a first solvent; Providing a shell source, which includes a zinc sulfide precursor, and the structural formula of the zinc sulfide precursor is shown in Formula (Ⅰ): Among them, R1 and R2 are each independently selected from hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, or one or more of them; R3, R4, R5, R6, and R7 each independently include hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, or one or more of them; the heteroatoms in the heteroalkyl, heteroalkenyl, heteroalkynyl, and heterocyclic group include one or more of N, S, O, P, and Si; the substituents of the substituted groups each independently include one or more of -NH, -F, -Cl, -Br, -I, -OH, -COOH, -NO, -SO H, -CHO, -SH, -OH, -OOCCH3, and -CN; Injecting the shell source into the core solution, reacting to obtain a nanomaterial.

2. The preparation method according to claim 1, wherein R1 and R2 are selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, formyl, nitro, substituted or unsubstituted C5-C 20 alkyl, substituted or unsubstituted C5-C 20 heteroalkyl, substituted or unsubstituted C5-C 20 alkenyl, substituted or unsubstituted C5-C 20 heteroalkenyl, substituted or unsubstituted C5-C 20 alkynyl, substituted or unsubstituted C5-C 20 heteroalkynyl, substituted or unsubstituted C5-C 20 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C3-C 20 acyloxy, substituted or unsubstituted C5-C 20 alkoxycarbonyl, substituted or unsubstituted C8-C 20 aryl, substituted or unsubstituted heterocyclic group having 5 to 15 ring atoms, or one or more of them; and / or R3, R4, R5, R6, R7 are selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, aldehyde, nitro, substituted or unsubstituted C5-C 20 alkyl, substituted or unsubstituted C5-C 20 heteroalkyl, substituted or unsubstituted C5-C 20 alkenyl, substituted or unsubstituted C5-C 20 heteroalkenyl, substituted or unsubstituted C5-C 20 alkynyl, substituted or unsubstituted C5-C 20 heteroalkynyl, substituted or unsubstituted C5-C 20 alkoxy, substituted or unsubstituted C3-C 20 acyloxy, substituted or unsubstituted C5-C 20 alkoxycarbonyl, substituted or unsubstituted C8-C 20 aryl, or one or more of substituted or unsubstituted heterocyclic groups having 5 to 15 ring atoms.

3. The preparation method according to claim 1, wherein The R1 is selected from C2-C 18 alkyl; and / or The R2 is selected from substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7; and / or R2 is selected from -N(C2H5)2, -OC 16 H 33 , -SC 16 H 33 , -NHC 16 H 33 , -P(OC 16 H 33 )2; and / or The zinc sulfide precursor includes one of 4. The preparation method according to claim 1, characterized in that, The preparation method of the core solution includes: providing a first metal source, a first anion source, and a second solvent, reacting to obtain a quantum dot core.

5. The preparation method according to claim 4, wherein The first metal source includes one or more of a cadmium source, a zinc source, a mercury source, a tin source, a lead source, a gallium source, an antimony source, an aluminum source, an indium source, a copper source; and / or The first anion source includes one or more of a sulfur source, a selenium source, a tellurium source, a nitrogen source, an arsenic source, a phosphorus source; and / or The first solvent and the second solvent each independently include one or more of oleylamine, diphenylphosphine, tri-n-octylphosphine, tri-n-octylphosphine oxide, tributyl phosphate, glyceryl caprylate, diethylpropylphenol; and / or The reaction temperature of the first metal source and the first anion source is 300°C to 350°C; the time is 1h to 4h.

6. The preparation method according to claim 1, wherein The shell source further includes a second metal source; the second metal source includes one or more of a cadmium source, a mercury source; the molar ratio of the zinc sulfide precursor to the second metal source is 5:(4 to 8); and / or After the shell source and the core solution react, it further includes adding a thiol ligand to obtain a nanomaterial; the thiol ligand includes one or more of propanethiol, butanethiol, octanethiol, dodecanethiol, benzenethiol, 1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, 1,2-ethanedithiol; and / or After the shell source and the core solution react, it further includes adding a precipitant to obtain a nanomaterial; the precipitant includes one or more of acetone, ethyl acetate, hexane, heptane, octane; and / or The reaction temperature of the shell source and the core solution is 280°C to 320°C; the time is 10 min to 60 min.

7. A nanomaterial, characterized in that, Prepared by the preparation method according to any one of claims 1 to 6, or the nanomaterial includes a quantum dot and a first ligand connected to the surface of the quantum dot, and the structural formula of the first ligand is shown in Formula (Ⅱ): wherein, R1 and R2 are each independently selected from hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, or one or more of the above; R3, R4, R5, R6, and R7 each independently include hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, aldehyde, nitro, substituted or unsubstituted C1-C 32 alkyl, substituted or unsubstituted C1-C 32 heteroalkyl, substituted or unsubstituted C2-C 32 alkenyl, substituted or unsubstituted C2-C 32 heteroalkenyl, substituted or unsubstituted C2-C 32 alkynyl, substituted or unsubstituted C2-C 32 heteroalkynyl, substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted C1-C 32 acyloxy, substituted or unsubstituted C1-C 32 alkoxycarbonyl, substituted or unsubstituted C6-C 20 aryl, or one or more of substituted or unsubstituted heterocyclic groups having 3 to 20 ring atoms; The heteroatoms in the heteroalkyl, heteroalkenyl, heteroalkynyl, heterocyclic group include one or more of N, S, O, P, Si; The substituents of the substitution each independently include one or more of -NH, -F, -Cl, -Br, -I, -OH, -COOH, -NO, -SOH, -CHO, -SH, -OH, -OOCCH3, -CN.

8. The nanomaterial according to claim 7, wherein R1 and R2 are selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, formyl, nitro, substituted or unsubstituted C5-C 20 alkyl, substituted or unsubstituted C5-C 20 heteroalkyl, substituted or unsubstituted C5-C 20 alkenyl, substituted or unsubstituted C5-C 20 heteroalkenyl, substituted or unsubstituted C5-C 20 alkynyl, substituted or unsubstituted C5-C 20 heteroalkynyl, substituted or unsubstituted C5-C 20 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7, substituted or unsubstituted C3-C 20 acyloxy, substituted or unsubstituted C5-C 20 alkoxycarbonyl, substituted or unsubstituted C8-C 20 aryl, substituted or unsubstituted heterocyclic group with 5 to 15 ring atoms, one or more of them; R3, R4, R5, R6, and R7 are selected from hydrogen, deuterium, halogen, cyano, hydroxy, carboxy, formyl, nitro, substituted or unsubstituted C5-C 20 alkyl, substituted or unsubstituted C5-C 20 heteroalkyl, substituted or unsubstituted C5-C 20 alkenyl, substituted or unsubstituted C5-C 20 heteroalkenyl, substituted or unsubstituted C5-C 20 alkynyl, substituted or unsubstituted C5-C 20 heteroalkynyl, substituted or unsubstituted C5-C 20 alkoxy, substituted or unsubstituted C3-C 20 acyloxy, substituted or unsubstituted C5-C 20 alkoxycarbonyl, substituted or unsubstituted C8-C 20 aryl, substituted or unsubstituted heterocyclic group with 5 to 15 ring atoms, one or more of them; Optionally, the R1 is selected from C2-C 18 alkyl; and / or Optionally, R2 is selected from substituted or unsubstituted C1-C 32 alkoxy, substituted or unsubstituted -NR3R4, substituted or unsubstituted -SR5, substituted or unsubstituted -PR6R7; and / or Optionally, R2 is selected from -N(C2H5)2, -OC 16 H 33 , -SC 16 H 33 , -NHC 16 H 33 , -P(OC 16 H 33 )2; and / or Optionally, the first ligand includes one of 9. The nanomaterial according to claim 7, wherein In the nanomaterial, the mass fraction of the first ligand is 7% to 8%; and / or The S of the first ligand is covalently bonded to the surface of the quantum dot; and / or The average particle size of the quantum dots is 10 nm to 12 nm; and / or The quantum dots include core-shell quantum dots.

10. The nanomaterial according to claim 9, characterized in that, The surface of the quantum dots contains metal M, and the structural formula of the connection between the quantum dots and the first ligand includes:

11. The nanomaterial according to claim 9, wherein The shell material of the core-shell quantum dots contains sulfur and zinc elements, and the S of the first ligand is connected to the zinc element; and / or The shell material of the core-shell quantum dots includes one or more of ZnS, ZnSeS, ZnSTe, CdZnS, HgZnS, CdZnSeS, CdZnSTe, HgZnSeS, and HgZnSTe; and / or The core material of the core-shell quantum dots includes one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds; the II-VI group 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 group compounds include one or more 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 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 group compounds include one or more of CuInS2, CuInSe2, and AgInS2.

12. The nanomaterial according to claim 7, characterized in that, The nanomaterial further includes a second ligand connected to the surface of the quantum dots; Optionally, the second ligand includes a thiol ligand, and the thiol ligand includes one or more of propanethiol, butanethiol, octanethiol, dodecanethiol, benzenethiol, 1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, 1,2-ethanedithiol; Optionally, in the nanomaterial, the mass fraction of the second ligand is 7% to 8%; Optionally, in the nanomaterial, the mass ratio of the first ligand to the second ligand is (7 to 8):(7 to 8).

13. An optoelectronic device, characterized in that, It includes a first electrode, a light-emitting layer, and a second electrode that are sequentially stacked, and the material of the light-emitting layer includes the nanomaterial prepared by the preparation method according to any one of claims 1 to 6, or the material of the light-emitting layer includes the nanomaterial according to any one of claims 7 to 12.

Images