阅读说明：本技术 复合材料及其制备方法、发光器件 (Composite material, preparation method thereof and light-emitting device ) 是由 何斯纳 吴龙佳 吴劲衡 于 2020-05-21 设计创作，主要内容包括：本发明属于显示器件技术领域,尤其涉及一种复合材料的制备方法,包括步骤：在含卤素气体的氛围下,对石墨炔进行热卤化处理,得到卤化石墨炔；获取金属化合物溶液和卤化石墨炔的有机溶液,将所述卤化石墨炔的有机溶液与所述金属化合物溶液混合处理,得到卤化石墨炔掺杂金属化合物的复合材料。本发明提供的复合材料的制备方法,操作简单,适用于工业化大规模生产和应用功能,卤化石墨炔掺杂金属化合物的复合材料,提高了电子传输层的电子传输能力,促进电子-空穴在发光层中有效地复合,降低激子累积对器件性能的影响,从而提高发光器件的光电性能。(The invention belongs to the technical field of display devices, and particularly relates to a preparation method of a composite material, which comprises the following steps: carrying out thermal halogenation treatment on the graphatidine in the atmosphere of halogen-containing gas to obtain halogenated graphatidine; obtaining a metal compound solution and an organic solution of halogenated graphite alkyne, and mixing the organic solution of halogenated graphite alkyne and the metal compound solution to obtain the halogenated graphite alkyne-doped metal compound composite material. The preparation method of the composite material provided by the invention is simple to operate, is suitable for industrial large-scale production and application functions, and the composite material of the halogenated graphite alkyne doped metal compound improves the electron transport capability of the electron transport layer, promotes the effective recombination of electron-hole in the luminescent layer, reduces the influence of exciton accumulation on the device performance, and thus improves the photoelectric performance of the luminescent device.)

1. A preparation method of a composite material is characterized by comprising the following steps:

carrying out thermal halogenation treatment on the graphatidine in the atmosphere of halogen-containing gas to obtain halogenated graphatidine;

obtaining a metal compound solution and an organic solution of halogenated graphite alkyne, and mixing the organic solution of halogenated graphite alkyne and the metal compound solution to obtain the halogenated graphite alkyne-doped metal compound composite material.

2. The method of preparing the composite material of claim 1, wherein the step of thermally halogenating the graphdiyne comprises: carrying out heat treatment on the graphate for 1-2 hours in the presence of anhydrous oxygen-free gas at the temperature of 250-350 ℃ and halogen-containing gas to obtain halogenated graphate; and/or the presence of a gas in the gas,

the halogen-containing gas atmosphere comprises: halogen gas and shielding gas.

3. The method according to claim 2, wherein the halogen-containing atmosphere comprises, in volume percent: 5-10% of halogen gas and 90-95% of protective gas; and/or the presence of a gas in the gas,

the halogen gas is selected from: at least one of fluorine gas, chlorine gas and bromine gas; and/or the presence of a gas in the gas,

the protective gas is selected from: at least one of nitrogen, argon, helium.

4. The method of preparing a composite material of claim 1, wherein the step of obtaining a solution of a metal compound comprises: under the condition that the temperature is 60-90 ℃, metal salt and an alkaline substance or a sulfur source are mixed and dissolved in a first organic solvent, and then are mixed and treated for 4-6 hours to obtain a metal compound solution; and/or the presence of a gas in the gas,

the step of mixing the organic solution of the halogenated graphdine with the metal compound solution comprises: and under the stirring condition of the temperature of 60-80 ℃, adding the organic solution of the halogenated graphite alkyne into the metal compound solution, reacting for 1-2 hours, and separating to obtain the composite material of the halogenated graphite alkyne doped metal compound.

5. The method for preparing the composite material according to claim 4, wherein the metal salt and the alkaline substance are mixed and dissolved in a system formed by the first organic solvent, and the pH value is 12-13; and/or the presence of a gas in the gas,

mixing and dissolving a metal salt and an alkaline substance in a system formed by dissolving the metal salt and the alkaline substance in a first organic solvent, wherein the molar ratio of metal ions to the alkaline substance is 1: (1.8-4.5); or

Mixing and dissolving metal salt and a sulfur source in a system after a first organic solvent, wherein the molar ratio of metal ions to the sulfur source is 1: (1-1.5); and/or the presence of a gas in the gas,

adding the organic solution of the halogenated graphdine into the system after the metal compound solution is added, wherein the molar ratio of the halogenated graphdine to the metal compound is (0.1-0.3): 1.

6. the method of claim 5, wherein the metal ion is a divalent metal ion, and the molar ratio of the metal ion to the basic substance is 1: (1.8-3);

the metal ion is tetravalent, and the molar ratio of the metal ion to the alkaline substance is 1: (3-4.5).

7. A method of preparing a composite material as claimed in any one of claims 4 to 6, wherein the metal salt is selected from: at least one of zinc salt, titanium salt and tin salt; and/or the presence of a gas in the gas,

the alkaline substance is selected from: at least one of ammonia water, potassium hydroxide, sodium hydroxide, lithium hydroxide, ethanolamine, ethylene glycol, diethanolamine, triethanolamine and ethylenediamine; and/or the presence of a gas in the gas,

the sulfur source is selected from: at least one of sodium sulfide, potassium sulfide, thiourea and amine sulfide; and/or the presence of a gas in the gas,

the first organic solvent is selected from: at least one of isopropanol, ethanol, propanol, butanol, and methanol; and/or the presence of a gas in the gas,

the organic solvent in the organic solution of halogenated graphdine is selected from: at least one of isopropanol, ethanol, propanol, butanol, and methanol.

8. The method of preparing a composite material according to claim 7, wherein the zinc salt is selected from the group consisting of: at least one of zinc acetate, zinc nitrate, zinc chloride, zinc sulfate, zinc acetate dihydrate; and/or the presence of a gas in the gas,

the titanium salt is selected from: at least one of titanium nitrate, titanium chloride, titanium sulfate and titanium bromide; and/or the presence of a gas in the gas,

the tin salt is selected from: at least one of tin nitrate, tin chloride, tin sulfate, tin methane sulfonate, tin ethane sulfonate and tin propane sulfonate.

9. A composite material, comprising: a halogenated graphatidine and a metal compound bound to the halogenated graphatidine.

10. The composite material of claim 9, wherein the halogenated graphdine comprises: at least one halogen selected from fluorine, chlorine and bromine; and/or the presence of a gas in the gas,

the metal compound includes: at least one of zinc oxide, titanium oxide, tin oxide, zinc sulfide, titanium sulfide, and tin sulfide; and/or the presence of a gas in the gas,

in the composite material, the molar ratio of the halogenated graphdiyne to the metal compound is (0.1-0.3): 1.

11. a light emitting device comprising an anode and a cathode disposed opposite each other, a quantum dot light emitting layer disposed between the anode and the cathode, and an electron transport layer disposed between the cathode and the quantum dot light emitting layer; the electron transport layer comprises a composite material prepared by the method of any one of claims 1 to 8, or comprises a composite material of any one of claims 9 to 10.

Technical Field

The invention belongs to the technical field of display devices, and particularly relates to a composite material and a preparation method thereof, and a light-emitting device.

Background

The semiconductor quantum dots have quantum size effect, people can realize the required light emission with specific wavelength by regulating and controlling the size of the quantum dots, and the tuning range of the light emission wavelength of the CdSe QDs can be from blue light to red light. In the conventional inorganic electroluminescent device, electrons and holes are injected from a cathode and an anode, respectively, and then recombined in a light emitting layer to form excitons for light emission.

In recent years, inorganic semiconductors have been studied as an electron transport layer in a relatively hot manner. Semiconductor materials such as nano ZnO, ZnS and the like are wide bandgap semiconductor materials, and attract the attention of a plurality of researchers due to the advantages of quantum confinement effect, size effect, excellent fluorescence characteristic and the like. ZnO is an n-type semiconductor material with a direct band gap, has a wide forbidden band of 3.37eV and a low work function of 3.7eV, and the structural characteristics of the energy band determine that ZnO can be used as a proper electron transport layer material. In addition, ZnS is a II-VI semiconductor material, has two different structures of sphalerite and wurtzite, and has the characteristics of stable chemical property of forbidden bandwidth (3.62eV), abundant resources, low price and the like. Therefore, in the last ten years, ZnO, ZnS II-VI and other conductor nano materials have shown great development potential in the research of fields such as photocatalysis, sensors, transparent electrodes, fluorescent probes, diodes, solar cells, lasers and the like.

At present, ZnO, ZnS and other semiconductor materials are poor in crystallinity, and a large number of active groups and surface defect states exist on the surface, so that loss of photocurrent is easily caused, and the performance of a device is reduced; meanwhile, the active groups can also cause bonding effect among the nanoparticles, which not only causes agglomeration among the particles to influence the dispersibility of the nanoparticles, but also reduces the injection efficiency of electrons and influences the electron and hole recombination efficiency in the quantum dot light-emitting layer. Therefore, the application performance of the semiconductor materials such as ZnO, ZnS and the like in the electron transport layer of the photoelectric device needs to be further improved.

Disclosure of Invention

The invention aims to provide a preparation method of a composite material, aiming at improving the electron transmission performance of the existing semiconductor materials such as ZnO, ZnS and the like to a certain extent and improving the photoelectric performance of devices.

It is another object of the present invention to provide a composite material.

It is still another object of the present invention to provide a light emitting device.

In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows:

a method of making a composite material comprising the steps of:

carrying out thermal halogenation treatment on the graphatidine in the atmosphere of halogen-containing gas to obtain halogenated graphatidine;

obtaining a metal compound solution and an organic solution of halogenated graphite alkyne, and mixing the organic solution of halogenated graphite alkyne and the metal compound solution to obtain the halogenated graphite alkyne-doped metal compound composite material.

Accordingly, a composite material comprising: a halogenated graphatidine and a metal compound bound to the halogenated graphatidine.

Correspondingly, the light-emitting device comprises an anode and a cathode which are oppositely arranged, a quantum dot light-emitting layer arranged between the anode and the cathode, and an electronic function layer arranged between the cathode and the quantum dot light-emitting layer; the electronic functional layer comprises a composite material prepared as described above, or comprises a composite material as described above.

Firstly, carrying out thermal halogenation treatment on the graphatidine in the atmosphere of halogen-containing gas to enable an alkyne bond in the graphatidine to be halogenated and connected with a halogen atom, thereby obtaining the halogenated graphatidine. With the introduction of halogen atoms, the delocalized pi orbit on the graphdine is overlapped with the 3d orbit above the halogen atoms, so that the electron affinity potential energy of the graphdine is obviously increased to form n-type doping. The halogenated graphdiyne with high affinity potential is beneficial to overcoming the energy barrier of electrons and effectively injecting the electrons into the LUMO energy level, so that the electron transport performance of the graphdiyne is improved. Then, after a metal compound solution is obtained, mixing the organic solution of the halogenated graphite alkyne with the metal compound solution, and obtaining the composite material of the halogenated graphite alkyne doped with the metal compound through stronger adsorption of the halogenated graphite alkyne and the metal element in the metal compound. According to the composite material prepared by the invention, on one hand, halogenated graphite alkyne provides a metal compound with a two-dimensional network structure with a special electronic structure and a hole structure, so that the metal compound is effectively prevented from agglomerating in the application process, and the stability of an electron transmission film is improved; on the other hand, by doping halogenated graphite alkyne, the hybridization between the pz orbit of the graphite alkyne and the 3d orbit of metal ions in the metal compound is realized, the electronic interaction can be generated between the graphite alkyne and the metal compound, and the electronic transmission capability of the composite material is improved. On the other hand, in the composite material of the halogenated graphite alkyne doped metal compound, the work function of the graphite alkyne is about 5.0eV and is between the electrode and the electron transport material such as the metal compound and the like, so that the electron transport barrier is reduced, the energy level matching of the electron transport layer and the electrode is facilitated, the electron transport capacity of the electron transport layer is improved, the effective recombination of electron-hole in the luminescent layer is promoted, the influence of exciton accumulation on the device performance is reduced, and the photoelectric performance of the luminescent device is improved.

The present invention provides a composite material comprising: the halogenated graphite alkyne and the metal compound combined on the halogenated graphite alkyne are in a two-dimensional network structure with a special electronic structure and a hole structure, so that the agglomeration of the metal compound in the application process is effectively prevented, and the stability of the electron transport film is improved. In addition, the metal compound is combined on the halogenated graphite alkyne, so that the hybridization effect between the pz orbit of the graphite alkyne and the 3d orbit of the metal ion in the metal compound is realized, the electronic interaction can be generated between the graphite alkyne and the metal compound, and the electronic transmission capability of the composite material is improved. In the composite material of the halogenated graphite alkyne doped metal compound, the work function of the graphite alkyne is about 5.0eV and is between the electrode and the electron transport material such as the metal compound, so that the electron transport barrier is reduced, the energy level matching of the electron transport layer and the electrode is facilitated, the electron transport capacity of the electron transport layer is improved, the effective recombination of electron-hole in the luminescent layer is promoted, the influence of exciton accumulation on the performance of the device is reduced, and the photoelectric performance of the luminescent device is improved.

The light-emitting device provided by the invention comprises the composite material which has good stability and high electron transmission efficiency and can reduce the electron transmission barrier between the electrode and the electron transmission material such as metal compound. Therefore, the energy level matching of the electron transport layer and the electrode is facilitated, the electron transport capability of the electron transport layer in the light-emitting device is improved, the effective recombination of electrons and holes in the light-emitting layer is promoted, the influence of exciton accumulation on the device performance is reduced, and the photoelectric performance of the light-emitting device is improved.

Drawings

Fig. 1 is a schematic flow chart of a method for preparing a composite material according to an embodiment of the present invention.

Fig. 2 is a light-emitting device of a positive type configuration according to an embodiment of the present invention.

Fig. 3 is an inverted light emitting device according to an embodiment of the present invention.

Detailed Description

In order to make the purpose, technical solution and technical effect of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention is clearly and completely described, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art without any inventive step in connection with the embodiments of the present invention shall fall within the scope of protection of the present invention.

In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

The weight of the related components mentioned in the description of the embodiments of the present invention may not only refer to the specific content of each component, but also represent the proportional relationship of the weight among the components, and therefore, the content of the related components is scaled up or down within the scope disclosed in the description of the embodiments of the present invention as long as it is in accordance with the description of the embodiments of the present invention. Specifically, the weight described in the description of the embodiment of the present invention may be a unit of mass known in the chemical industry field, such as μ g, mg, g, and kg.

As shown in fig. 1, an embodiment of the present invention provides a method for preparing a composite material, including the following steps:

s10, carrying out thermal halogenation treatment on the graphate under the atmosphere of halogen-containing gas to obtain halogenated graphate;

s20, obtaining a metal compound solution and an organic solution of halogenated graphite alkyne, and mixing the organic solution of halogenated graphite alkyne and the metal compound solution to obtain the halogenated graphite alkyne-doped metal compound composite material.

According to the preparation method of the composite material provided by the embodiment of the invention, firstly, under the atmosphere of halogen-containing gas, the graphite alkyne is subjected to thermal halogenation treatment, so that the alkyne bond in the graphite alkyne is halogenated and connected with the halogen atom, and the halogenated graphite alkyne is obtained. With the introduction of halogen atoms, the delocalized pi orbit on the graphdine is overlapped with the 3d orbit above the halogen atoms, so that the electron affinity potential energy of the graphdine is obviously increased to form n-type doping. The halogenated graphdiyne with high affinity potential is beneficial to overcoming the energy barrier of electrons and effectively injecting the electrons into the LUMO energy level, so that the electron transport performance of the graphdiyne is improved. And then, after a metal compound solution is obtained, mixing the organic solution of the halogenated graphite alkyne with the metal compound solution for treatment, and obtaining the composite material of the halogenated graphite alkyne doped metal compound through stronger adsorption of metal atoms in the halogenated graphite alkyne and metal elements in the metal compound. According to the composite material prepared by the embodiment of the invention, on one hand, halogenated graphite alkyne provides a metal compound with a two-dimensional network structure with a special electronic structure and a hole structure, so that the metal compound is effectively prevented from agglomerating in the application process, and the stability of an electron transmission film is improved; on the other hand, by doping halogenated graphite alkyne, the hybridization between the pz orbit of the graphite alkyne and the 3d orbit of metal ions in the metal compound is realized, the electronic interaction can be generated between the graphite alkyne and the metal compound, and the electronic transmission capability of the composite material is improved. On the other hand, in the composite material of the halogenated graphite alkyne doped metal compound, the work function of the graphite alkyne is about 5.0eV and is between the electrode and the electron transport material such as the metal compound and the like, so that the electron transport barrier is reduced, and the energy level matching of the electron transport layer and the electrode is facilitated. The electron transport capability of the electron transport layer is improved, the effective recombination of electron-hole in the luminescent layer is promoted, and the influence of exciton accumulation on the performance of the device is reduced, so that the photoelectric performance of the luminescent device is improved.

Specifically, in example S10, the graphatidyne was subjected to a thermal halogenation treatment in an atmosphere containing a halogen gas, to thereby obtain a halogenated graphatidyne. According to the embodiment of the invention, under the atmosphere of halogen-containing gas, the graphite alkyne is subjected to thermal halogenation treatment, so that the alkyne bond in the graphite alkyne is halogenated and connected with the halogen atom, and the halogenated graphite alkyne is obtained. With the introduction of halogen atoms, the delocalized pi orbit on the graphdine is overlapped with the 3d orbit above the halogen atoms, so that the electron affinity potential energy of the graphdine is obviously increased to form n-type doping. The halogenated graphdiyne with high affinity potential is beneficial to overcoming the energy barrier of electrons and effectively injecting the electrons into the LUMO energy level, so that the electron transport performance of the graphdiyne is improved. According to the embodiment of the invention, 90-100% of acetylene bonds can be completely halogenated by controlling the temperature of thermal halogenation treatment, the concentration of halogen gas and the reaction time, namely, carbon atoms on the original acetylene bonds are respectively connected with two halogen atoms.

The present invention has the structure represented by sp and sp²A novel carbon allotrope-graphite alkyne formed by hybridization is used as a base material, and is a two-dimensional plane hyperconjugated structure which is formed by conjugating and connecting benzene rings by 1, 3-diyne bonds and has rich carbon chemical bonds and a huge conjugated system, thereby not only becoming a good electron acceptor due to the huge highly conjugated structure, but also having good electron donating property due to the self-owned mass of free electrons, and having special electronic structure and hole structure, excellent chemical and thermal stability, semiconductor performance and other properties. When the metal compound is applied to the composite material, not only an attachment carrier is provided for the metal compound, the dispersion stability of the metal compound is improved, but also the electron transmission performance of the metal compound can be effectively improved, and the existence of electrons-holes in a luminescent layer is promotedEffectively compound, thereby improving the photoelectric performance of the light-emitting device.

In some embodiments, the step of thermally halogenating the graphdiyne comprises: and carrying out heat treatment on the graphate for 1-2 hours in the presence of anhydrous oxygen-free gas at the temperature of 250-350 ℃ and halogen-containing gas to obtain halogenated graphate. According to the embodiment of the invention, under the condition that the temperature is 250-350 ℃, halogen gas is adopted to halogenate the graphdiyne, and the halogen gas has high chemical activity at the temperature, can open the alkyne bond to connect with halogen, and has a good modification effect on the alkyne bond in the graphdiyne. In some embodiments, the graphdiyne powder is spread on a boat-shaped crucible, placed in a muffle furnace and continuously introduced with inert gas to remove air and moisture in the muffle furnace; and (3) heating the muffle furnace to 250-350 ℃, switching the inert gas into halogen gas, keeping the temperature, continuously introducing for 1-2 hours, cutting off the halogen gas source, and cooling to room temperature to obtain the halogenated graphite alkyne.

In some embodiments, the halogen-containing gas atmosphere comprises: halogen gas and shielding gas. In some embodiments, the shielding gas is selected from gases that provide an inert atmosphere for the thermal halogenation process of the graphdiyne. In some embodiments, the atmosphere containing the halogen gas comprises, in volume percent: 5% -10% of halogen gas and 90-95% of protective gas, if the concentration of the halogen gas is too high, the two-dimensional carbon structure of the graphdiyne is easily damaged by strong oxidizing property of the graphdiyne; if the concentration is too low, the gas-solid molecule contact is unstable, and the reaction activity is low. In some embodiments, the halogen gas is selected from: at least one of fluorine gas, chlorine gas and bromine gas. In some embodiments, the shielding gas is capable of providing an inert atmosphere for the thermal halogenation process of the graphdiyne to prevent high temperature oxidation of the graphdiyne; and the concentration/content of halogen gas in the reaction system can be adjusted, so that the thermal halogenation treatment effect of the graphite alkyne can be adjusted. For example, the shielding gas is selected from: at least one of nitrogen, argon, helium.

Specifically, in step S20, a metal compound solution and an organic solution of halogenated graphdiyne are obtained, and the organic solution of halogenated graphdiyne and the metal compound solution are mixed to obtain a composite material of halogenated graphdiyne doped with a metal compound. After the metal compound solution is obtained, the organic solution of the halogenated graphite alkyne and the metal compound solution are mixed, and the composite material of the halogenated graphite alkyne doped metal compound is obtained through stronger adsorption between the halogenated graphite alkyne and metal elements in the metal compound. The composite material has good dispersion stability, realizes the hybridization between the pz orbit of the graphite alkyne and the 3d orbit of the metal ions in the metal compound by doping the halogenated graphite alkyne, can generate electronic interaction between the graphite alkyne and the metal compound, and improves the electronic transmission capability of the composite material. And the graphdiyne can reduce the transmission barrier of electrons, is beneficial to the energy level matching of the electron transmission layer and an electrode, improves the electron transmission capability of the electron transmission layer, promotes the effective recombination of electrons and holes in a light-emitting layer, reduces the influence of exciton accumulation on the performance of a device, and further improves the photoelectric performance of the light-emitting device.

In some embodiments, the step of obtaining a metal compound solution comprises: under the condition that the temperature is 60-90 ℃, metal salt and an alkaline substance or a sulfur source are mixed and dissolved in a first organic solvent, and then mixed and treated for 4-6 hours to obtain a metal compound solution. In the embodiment of the invention, under the condition that the temperature is 60-90 ℃, metal salt and alkaline substance or sulfur source are mixed and dissolved in a first organic solvent, then the mixture is mixed and treated for 4-6 hours, and the metal salt and the alkaline substance react to generate hydroxide, then the condensation polymerization reaction is carried out, and metal salt oxide is generated by dehydration, or metal salt and sulfur source react to generate metal salt sulfide. After the reaction or cooling, using weak polar and non-polar solvents such as ethyl acetate, heptane, octane and the like as a precipitator to precipitate metal compounds of metal oxides or metal salt sulfides, and obtaining a metal compound solution through multiple washing and extraction. The metal compound solution can be directly used for subsequent reaction with halogenated graphite alkyne without drying, and if the metal compound is dried, some active groups on the surface of the material can be damaged, so that the subsequent doping combination reaction with the halogenated graphite alkyne is not facilitated.

In some embodiments, the metal salt is mixed with a basic materialAnd mixing and dissolving the mixture in a system after the first organic solvent, wherein the pH value is 12-13. In some embodiments, the metal salt and the basic substance are mixed and dissolved in the first organic solvent, and the molar ratio of the metal ion to the basic substance is 1: (1.8-4.5). In some embodiments, the metal ion is a divalent metal ion, and the molar ratio of the metal ion to the basic material is 1: (1.8-3). In some embodiments, the metal ion is a tetravalent metal ion, and the molar ratio of the metal ion to the basic species is 1: (3-4.5). In the embodiment of the invention, metal salt and alkaline substances are reacted to prepare the metal compound of the metal salt oxide, the pH value and the addition amount of the alkaline substances in a reaction system are directly related to the metal compound of the metal salt oxide, and when the H value in the system is less than 12, the alkaline substances are insufficient, the metal salt is excessive, and the reaction is insufficient; when the H value in the system is more than 12, the pH value is too high, so that the hydrolysis and polycondensation speed of the sol in the system is reduced, and the preparation of the metal salt oxide semiconductor material is not facilitated. Similarly, when the metal ion is Zn²⁺When the divalent metal is equal, the molar ratio of the metal ions to the alkaline substance is 1: (1.8-3) when the metal ion is Ti⁴⁺、Sn⁴⁺When the tetravalent metal is contained, the molar ratio of the metal ions to the basic substance is 1: (3-4.5), if the alkaline substances are excessive, the hydrolysis and polycondensation speed of the sol in the system can be reduced, and the preparation of the metal salt oxide semiconductor material is not facilitated; if the alkaline substance is too little, the metal salt is excessive and the reaction is insufficient.

In some embodiments, the metal salt and the sulfur source are mixed and dissolved in the system after the first organic solvent, and the molar ratio of the metal ion to the sulfur source is 1: (1-1.5). According to the embodiment of the invention, metal salt reacts with a sulfur source to prepare the metal compound of metal salt sulfide, and the molar ratio of metal ions to the sulfur source is 1: (1-1.5), the method is favorable for preparing the metal salt sulfide semiconductor material with small and uniform particle size, and when the molar ratio of the metal ions to the sulfur source is less than 1:1, excessive zinc salt and less sulfur source are generated, so that the zinc sulfide is not sufficiently generated; when the molar ratio of the metal ions to the sulfur source is greater than 1: at 1.5, the sulfur salt is excessive, and the impurity compound is easily formed and is not easily removed.

In some embodiments, the step of treating the organic solution of halogenated graphdiyne in admixture with the metal compound solution comprises: and under the stirring condition of the temperature of 60-80 ℃, adding the organic solution of the halogenated graphite alkyne into the metal compound solution, reacting for 1-2 hours, and separating to obtain the composite material of the halogenated graphite alkyne doped metal compound. In the embodiment of the invention, under the stirring condition of the temperature of 60-80 ℃, after the organic solution of the halogenated graphite alkyne is added into the metal compound solution in a dropping mode or the like, the added halogenated graphite alkyne can be rapidly and uniformly combined with the metal compound, and the composite material of the halogenated graphite alkyne doped metal compound is obtained through stronger adsorption between the halogenated graphite alkyne and metal elements in the metal compound. The halogenated graphite alkyne provides a two-dimensional network structure with a special electronic structure and a hole structure for the metal compound, effectively prevents the metal compound from agglomerating in the application process, and improves the stability of the electron transport film. Meanwhile, by doping the halogenated graphite alkyne, the hybridization between the pz orbit of the graphite alkyne and the 3d orbit of the metal ions in the metal compound is realized, the electronic interaction can be generated between the halogenated graphite alkyne and the metal compound, and the electronic transmission capability of the metal compound is improved.

In some embodiments, the organic solution of the halogenated graphtylene is added to the system after the metal compound solution, and the molar ratio of the halogenated graphtylene to the metal compound is (0.1-0.3): 1. when the molar ratio of the halogenated graphdine to the metal compound is less than 0.1:1, the metal compound is excessive, the metal compound cannot be well dispersed, and the improvement effect on the conductivity is small; when the molar ratio of the halogenated graphdine to the metal compound is greater than 0.3:1, excessive halogenated graphite alkyne cannot generate hybridization with metal ions in the gold nano material, and the electron transmission performance of the composite transmission material is not obviously improved. In some embodiments, the molar ratio of the halogenated graphdiyne to the metal compound may be 0.1:1, 0.15:1, 0.2:1, 0.25:1, or 0.3:1, and the like.

In some embodiments, the metal salt is selected from: at least one of zinc salt, titanium salt and tin salt. In some embodiments, the zinc salt is selected from: at least one of zinc acetate, zinc nitrate, zinc chloride, zinc sulfate, and zinc acetate dihydrate. In some embodiments, the titanium salt is selected from: at least one of titanium nitrate, titanium chloride, titanium sulfate and titanium bromide. In some embodiments, the tin salt is selected from: at least one of tin nitrate, tin chloride, tin sulfate, tin methane sulfonate, tin ethane sulfonate and tin propane sulfonate. The metal salts adopted in the embodiment of the invention can react with alkaline substances or sulfur sources to generate metal compounds with electron transport characteristics.

In some embodiments, the alkaline material is selected from: at least one of ammonia water, potassium hydroxide, sodium hydroxide, lithium hydroxide, ethanolamine, ethylene glycol, diethanolamine, triethanolamine and ethylenediamine, wherein the alkaline substances can react with metal salts such as zinc salt, titanium salt, tin salt and the like to generate hydroxide, and then the hydroxide is subjected to polycondensation reaction and dehydration to generate the metal salt oxide semiconductor material.

In some embodiments, the sulfur source is selected from: at least one of sodium sulfide, potassium sulfide, thiourea and amine sulfide, wherein the sulfur source can react with metal salts such as zinc salt, titanium salt and tin salt to generate metal salt sulfide semiconductor material.

In some embodiments, the first organic solvent is selected from: the organic solvents have better solubility to metal salts, alkaline substances and sulfur sources, provide a better solvent system for the reaction among the substances and are beneficial to the reaction.

In some embodiments, the organic solvent in the organic solution of halogenated graphdiynes is selected from the group consisting of: the organic solvents have good dispersion characteristics on halogenated graphite alkyne, and are beneficial to mutual doping reaction between the halogenated graphite alkyne and the metal compound, so that the composite material of the halogenated graphite alkyne doped with the metal compound is obtained.

Correspondingly, the embodiment of the invention also provides a composite material, which comprises: a halogenated graphatidine and a metal compound bound to the halogenated graphatidine.

The composite material provided by the embodiment of the invention comprises: the halogenated graphite alkyne and the metal compound combined on the halogenated graphite alkyne are in a two-dimensional network structure with a special electronic structure and a hole structure, so that the agglomeration of the metal compound in the application process is effectively prevented, and the stability of the electron transport film is improved. In addition, the metal compound is combined on the halogenated graphite alkyne, so that the hybridization effect between the pz orbit of the graphite alkyne and the 3d orbit of the metal ion in the metal compound is realized, the electronic interaction can be generated between the graphite alkyne and the metal compound, and the electronic transmission capability of the composite material is improved. In the composite material of the halogenated graphite alkyne doped metal compound, the work function of the graphite alkyne is about 5.0eV and is between the electrode and the electron transport material such as the metal compound, so that the electron transport barrier is reduced, the energy level matching of the electron transport layer and the electrode is facilitated, the electron transport capacity of the electron transport layer is improved, the effective recombination of electron-hole in the luminescent layer is promoted, the influence of exciton accumulation on the performance of the device is reduced, and the photoelectric performance of the luminescent device is improved.

In some embodiments, the halogenated graphdiyne comprises: at least one halogen selected from fluorine, chlorine and bromine. In the preparation of the halogenated graphite alkyne, 90-100% of alkyne bonds in the halogenated graphite alkyne can be completely halogenated by controlling the temperature of thermal halogenation treatment, the concentration of halogen gas and the reaction time, namely, two halogen atoms are respectively connected to carbon atoms on the original alkyne bonds.

In some embodiments, the metal compound is selected from: at least one of zinc oxide, titanium oxide, tin oxide, zinc sulfide, titanium sulfide, and tin sulfide.

In some embodiments, the molar ratio of the halogenated graphdiyne to the metal compound is (0.1 to 0.3): 1.

correspondingly, the embodiment of the invention also provides a light-emitting device, which comprises an anode and a cathode which are oppositely arranged, a quantum dot light-emitting layer arranged between the anode and the cathode, and an electronic functional layer arranged between the cathode and the quantum dot light-emitting layer; the electronic function layer comprises the composite material prepared by the method or comprises the composite material.

The light-emitting device provided by the embodiment of the invention comprises the composite material which has good stability and high electron transmission efficiency and can reduce the electron transmission barrier between the electrode and the electron transmission materials such as metal compounds. Therefore, the energy level matching of the electron transport layer and the electrode is facilitated, the electron transport capability of the electron transport layer in the light-emitting device is improved, the effective recombination of electrons and holes in the light-emitting layer is promoted, the influence of exciton accumulation on the device performance is reduced, and the photoelectric performance of the light-emitting device is improved.

In some embodiments, the light emitting device of the embodiments of the present invention includes a positive structure and a negative structure.

In one embodiment, a positive type structure light emitting device includes a stacked structure of an anode and a cathode which are oppositely disposed, a light emitting layer disposed between the anode and the cathode, and the anode is disposed on a substrate. Further, a hole function layer such as a hole injection layer, a hole transport layer, an electron blocking layer and the like can be arranged between the anode and the light-emitting layer; an electron-transporting layer, an electron-injecting layer, a hole-blocking layer, and other electron-functional layers may be further disposed between the cathode and the light-emitting layer, as shown in fig. 2. In some embodiments of positive-type structure devices, the light-emitting device includes a substrate, an anode disposed on a surface of the substrate, a hole transport layer disposed on a surface of the anode, a light-emitting layer disposed on a surface of the hole transport layer, an electron transport layer disposed on a surface of the light-emitting layer, and a cathode disposed on a surface of the electron transport layer.

In one embodiment, an inversion structure light emitting device includes a stacked structure of an anode and a cathode disposed opposite to each other, a light emitting layer disposed between the anode and the cathode, and the cathode disposed on a substrate. Further, a hole function layer such as a hole injection layer, a hole transport layer, an electron blocking layer and the like can be arranged between the anode and the light-emitting layer; an electron functional layer such as an electron transport layer, an electron injection layer, and a hole blocking layer may be further disposed between the cathode and the light emitting layer, as shown in fig. 3. In some embodiments of the device with the inverted structure, the light-emitting device comprises a substrate, a cathode arranged on the surface of the substrate, an electron transport layer arranged on the surface of the cathode, a light-emitting layer arranged on the surface of the electron transport layer, a hole transport layer arranged on the surface of the light-emitting layer, and an anode arranged on the surface of the hole transport layer.

In further embodiments, the substrate layer comprises a rigid, flexible substrate, or the like;

the anode includes: ITO, FTO or ZTO, etc.;

the hole injection layer includes PEODT: PSS (poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonic acid)), WoO₃、MoO₃、NiO、V₂O₅HATCN (2,3,6,7,10, 11-hexacyano-1, 4,5,8,9, 12-hexaazatriphenylene), CuS, etc.;

the hole transport layer can be a micromolecular organic matter or a macromolecule conducting polymer, and comprises the following components: TFB (Poly [ (9, 9-di-N-octylfluorenyl-2, 7-diyl) -alt- (4,4' - (N- (4-N-butyl) phenyl) -diphenylamine)]) PVK (polyvinylcarbazole), TCTA (4,4 '-tris (carbazol-9-yl) triphenylamine), TAPC (4,4' -cyclohexylbis [ N, N-bis (4-methylphenyl) aniline)]) Poly-TBP, Poly-TPD, NPB (N, N ' -diphenyl-N, N ' - (1-naphthyl) -1,1' -biphenyl-4, 4' -diamine), CBP (4,4' -bis (9-carbazole) biphenyl), peot: PSS, MoO₃、WoO₃、NiO、CuO、V₂O₅CuS, and the like or a mixture of any combination thereof, and can also be other high-performance hole transport materials.

The luminescent layer is a quantum dot luminescent layer, wherein the quantum dot is one of red, green and blue. Including but not limited to: at least one of the semiconductor compounds of II-IV group, II-VI group, II-V group, III-VI group, IV-VI group, I-III-VI group, II-IV-VI group and II-IV-V group of the periodic table of the elements, or at least two of the semiconductor compounds. In some embodiments, the quantum dot light emitting layer material is selected from: at least one semiconductor nanocrystal compound of CdSe, CdS, CdTe, ZnO, ZnSe, ZnS, ZnTe, HgS, HgSe, HgTe and CdZnSe, or at least two semiconductor nanocrystal compounds with mixed type, gradient mixed type, core-shell structure type or combined type structures. In other embodiments, the quantum dot light emitting layer material is selected from: at least one semiconductor nanocrystal compound of InAs, InP, InN, GaN, InSb, InAsP, InGaAs, GaAs, GaP, GaSb, AlP, AlN, AlAs, AlSb, CdSeTe and ZnCdSe, or a semiconductor nanocrystal compound with a mixed type, a gradient mixed type, a core-shell structure type or a combined type of at least two components. In other embodiments, the quantum dot light emitting layer material is selected from: at least one of a perovskite nanoparticle material (in particular a luminescent perovskite nanoparticle material), a metal nanoparticle material, a metal oxide nanoparticle material. The quantum dot materials have the characteristics of quantum dots, and have good photoelectric properties;

the electron transport layer comprises the composite material;

the cathode includes: al, Ag, Au, Cu, Mo, or an alloy thereof.

In some embodiments, the fabrication of the light emitting device according to embodiments of the present invention includes the steps of:

s30, obtaining a substrate deposited with an anode;

s40, growing a hole transport layer on the surface of the anode;

s50, depositing a quantum dot light-emitting layer on the hole transport layer;

and S60, finally depositing an electron transmission layer on the quantum dot light-emitting layer, and depositing a cathode on the electron transmission layer to obtain the light-emitting device.

In some embodiments, in step S30, in order to obtain a high-quality zinc oxide nanomaterial film, the ITO substrate needs to undergo a pretreatment process. The basic specific processing steps include: and cleaning the ITO conductive glass with a cleaning agent to primarily remove stains on the surface, then sequentially and respectively ultrasonically cleaning the ITO conductive glass in deionized water, acetone, absolute ethyl alcohol and deionized water for 20min to remove impurities on the surface, and finally drying the ITO conductive glass with high-purity nitrogen to obtain the ITO anode.

In some embodiments, in step S40, the step of growing the hole transport layer includes: depositing a prepared solution of the hole transport material on an ITO substrate to form a film in modes of spin coating and the like; the film thickness is controlled by adjusting the concentration of the solution, the spin-coating speed and the spin-coating time, and then a thermal annealing process is performed at an appropriate temperature.

In some embodiments, the step of depositing the quantum dot light-emitting layer on the hole transport layer in step S50 includes: and depositing the prepared luminescent material solution with a certain concentration on the hole transport layer in a spin coating mode and other modes, controlling the thickness of the luminescent layer to be about 20-60 nm by adjusting the concentration of the solution, the spin coating speed and the spin coating time, and drying at a proper temperature to form the quantum dot luminescent layer.

In some embodiments, the step of depositing an electron transport layer on the quantum dot light emitting layer in step S60 includes: the electron transmission layer is a zinc oxide nano material (a/c-ZnO) film with a crystalline phase and an amorphous phase mixed, and the zinc oxide nano material comprises the following components in percentage by weight: the prepared zinc oxide composite material solution with a certain concentration is deposited on the quantum dot light-emitting layer in a spin coating mode and the like, the thickness of the electron transmission layer is controlled to be about 20-60 nm by adjusting the concentration of the solution, the spin coating speed (preferably, the rotating speed is 2000-6000 rpm) and the spin coating time, and then the electron transmission layer film is formed by annealing at the temperature of 200-250 ℃.

In some embodiments, in step S60, the step of preparing the cathode includes: the substrate deposited with the functional layers is placed in an evaporation bin, a layer of 15-30nm metal silver or aluminum is thermally evaporated through a mask plate to serve as a cathode, or a nano Ag wire or a Cu wire is used, so that a carrier can be smoothly injected due to the small resistance.

Further, the obtained photoelectric device is subjected to packaging treatment, and the packaging treatment can adopt a common machine for packaging and can also adopt manual packaging. Preferably, the oxygen content and the water content in the packaging treatment environment are both lower than 0.1ppm so as to ensure the stability of the device.

In order to make the above implementation details and operations of the present invention clearly understood by those skilled in the art and to make the advanced performance of the composite material, the preparation method thereof and the photoelectric device of the embodiments of the present invention obviously manifest, the above technical solutions are exemplified by a plurality of embodiments.

Example 1

An electron transport film of F @ graphite alkyne doped ZnS comprises the following steps:

firstly, 1g of graphdine powder was spread on a boat-shaped crucible, placed in a muffle furnace and continuously purged with argon. And (3) after exhausting for 20min, heating the muffle furnace to 250 ℃, switching argon into fluorine-containing gas (5% fluorine gas and 95% argon gas), preserving the temperature for 1h, cutting off the fluorine-containing gas, and cooling to room temperature to obtain the F @ graphite alkyne.

② adding proper amount of zinc chloride into 50ml of ethanol to form solution with total concentration of 0.5M, stirring and dissolving at 70 ℃. A solution of sodium sulfide dissolved in 10ml of ethanol (molar ratio, S) was added^2-：Zn²⁺1.2: 1). Stirring was continued at 70 ℃ for 4h to give a homogeneous ZnS solution.

Thirdly, slowly dripping F @ graphite alkyne into the ZnS solution, dispersing the F @ graphite alkyne in 10ml of ethanol solution (the molar ratio of F @ graphite alkyne: ZnS is 0.2:1), and continuously stirring at 70 ℃ for 1.5h to obtain the F @ graphite alkyne doped ZnS solution.

Fourthly, after the solution is cooled, spin-coating the solution on the processed ITO by a spin coater and annealing the solution at 200 ℃ to obtain the F @ graphite alkyne doped ZnS electron transport film.

Example 2

A Cl @ graphite alkyne-doped ZnO electron transport film comprises the following steps:

firstly, 1g of graphdine powder was spread on a boat-shaped crucible, placed in a muffle furnace and continuously purged with argon. And (3) after exhausting for 20min, heating the muffle furnace to 300 ℃, switching argon into chlorine-containing gas (8% chlorine and 92% argon), keeping the temperature for 1.5h, cutting off the chlorine-containing gas, and cooling to room temperature to obtain the Cl @ graphite alkyne.

② adding proper amount of zinc nitrate into 50ml of propanol to form solution with total concentration of 0.5M, stirring and dissolving at 80 ℃. A solution of sodium hydroxide dissolved in 10ml of propanol (molar ratio, OH) was added^-：Zn²⁺2: 1). Stirring was continued at 80 ℃ for 4h to give a homogeneous ZnO solution.

③ slowly dripping Cl @ graphite alkyne into the ZnO solution to disperse in 10ml of propanol solution (molar ratio, Cl @ graphite alkyne: ZnO ═ 0.3:1), and continuously stirring for 2h at 80 ℃ to obtain the Cl @ graphite alkyne doped ZnO solution.

Fourthly, after the solution is cooled, depositing on the treated ITO by a spin coater and annealing at 150 ℃ to obtain the Cl @ graphite alkyne-doped ZnO electron transport film.

Example 3

Br @ graphite alkyne doped TiO₂A dissolved electron transport film comprising the steps of:

firstly, 1g of graphdine powder was spread on a boat-shaped crucible, placed in a muffle furnace and continuously purged with argon. And (3) after exhausting for 20min, heating the muffle furnace to 350 ℃, switching argon into bromine-containing gas (10% of bromine gas and 90% of argon), preserving the temperature for 2h, cutting off the bromine-containing gas, and cooling to room temperature to obtain Br @ graphite alkyne.

② adding a proper amount of titanium sulfate into 50ml of methanol to form a solution with the total concentration of 0.5M, and stirring and dissolving at 60 ℃. A solution of potassium hydroxide dissolved in 10ml of methanol (molar ratio, OH) was added^-：Ti⁴⁺4: 1). Stirring at 60 deg.C for 4 hr to obtain uniform TiO₂And (3) solution.

③ to TiO₂Slowly dripping Br @ graphite alkyne into the solution, dispersing the Br @ graphite alkyne into 10ml methanol solution (molar ratio, Br @ graphite alkyne: ZnO ═ 0.1:1), and continuously stirring for 1h at 60 ℃ to obtain Br @ graphite alkyne doped TiO₂And (3) solution.

Fourthly, after the solution is cooled, spraying the solution on the treated ITO by a spin coater and annealing the solution at 200 ℃ to obtain Br @ graphite alkyne doped TiO₂Dissolved electron transport films.

Example 4

A quantum dot light emitting diode with a positive structure comprises a laminated structure of an anode and a cathode which are oppositely arranged, wherein the anode is arranged on a substrate, a quantum dot light emitting layer is arranged between the anode and the cathode, an electron transport layer is arranged between the cathode and the quantum dot light emitting layer, a hole transport layer is arranged between the anode and the quantum dot light emitting layer, and the anode is arranged on the substrate. Wherein the material of the substrateThe material is a glass sheet, the anode is made of an ITO substrate, the hole transport layer is made of a TFB material, the electron transport layer is made of an F @ graphite alkyne doped ZnS nano material obtained by the method in the embodiment 1, the electron transport layer is prepared by annealing at 250 ℃, and the cathode is made of Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Example 5

A quantum dot light emitting diode with a positive structure comprises a laminated structure of an anode and a cathode which are oppositely arranged, wherein the anode is arranged on a substrate, a quantum dot light emitting layer is arranged between the anode and the cathode, an electron transport layer is arranged between the cathode and the quantum dot light emitting layer, a hole transport layer is arranged between the anode and the quantum dot light emitting layer, and the anode is arranged on the substrate. The substrate is made of a glass sheet, the anode is made of an ITO (indium tin oxide) substrate, the hole transport layer is made of a TFB (tunneling thin film transistor), the electron transport layer is made of a Cl @ graphite alkyne-doped ZnO nanomaterial obtained by the method in the embodiment 2, the electron transport layer is prepared by annealing at 250 ℃, and the cathode is made of Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Example 6

A quantum dot light emitting diode with a positive structure comprises a laminated structure of an anode and a cathode which are oppositely arranged, wherein the anode is arranged on a substrate, a quantum dot light emitting layer is arranged between the anode and the cathode, an electron transport layer is arranged between the cathode and the quantum dot light emitting layer, a hole transport layer is arranged between the anode and the quantum dot light emitting layer, and the anode is arranged on the substrate. Wherein the substrate is made of glass sheet, the anode is made of ITO substrate, the hole transport layer is made of TFB, and the electron transport layer is made of Br @ graphite alkyne doped TiO obtained by the method in the embodiment 3₂The nano material is annealed at the temperature of 250 ℃ to prepare an electron transport layer, and the cathode is made of Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Example 7

The quantum dot light-emitting diode with the inversion structure comprises an anode and a cathode which are oppositely arranged, wherein the cathode is arranged on a substrate, a quantum dot light-emitting layer is arranged between the anode and the cathode, an electron transmission layer is arranged between the cathode and the quantum dot light-emitting layer, a hole transmission layer is arranged between the anode and the quantum dot light-emitting layer, and the anode is arranged on the substrate. The material of the substrate is a glass sheet, the material of the anode is an ITO substrate, the material of the hole transport layer is TFB, the material of the electron transport layer is the F @ graphite alkyne doped ZnS nano material obtained by the method in the embodiment 1, the electron transport layer is prepared by annealing at 250 ℃, and the material of the cathode is Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Example 8

The quantum dot light-emitting diode with the inversion structure comprises an anode and a cathode which are oppositely arranged, wherein the anode is arranged on a substrate, a quantum dot light-emitting layer is arranged between the anode and the cathode, an electron transmission layer is arranged between the cathode and the quantum dot light-emitting layer, a hole transmission layer is arranged between the anode and the quantum dot light-emitting layer, and the anode is arranged on the substrate. The substrate is made of a glass sheet, the anode is made of an ITO (indium tin oxide) substrate, the hole transport layer is made of a TFB (tunneling thin film transistor), the electron transport layer is made of a Cl @ graphite alkyne-doped ZnO nanomaterial obtained by the method in the embodiment 2, the electron transport layer is prepared by annealing at 250 ℃, and the cathode is made of Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Example 9

The quantum dot light-emitting diode with the inversion structure comprises a laminated structure of an anode and a cathode which are oppositely arranged, wherein the anode is arranged on a substrate, a quantum dot light-emitting layer is arranged between the anode and the cathode, an electron transmission layer is arranged between the cathode and the quantum dot light-emitting layer, and a hole transmission layer is arranged between the anode and the quantum dot light-emitting layerAnd the anode is arranged on the substrate. Wherein the substrate is made of glass sheet, the anode is made of ITO substrate, the hole transport layer is made of TFB, and the electron transport layer is made of Br @ graphite alkyne doped TiO obtained by the method in the embodiment 3₂The nano material is annealed at the temperature of 250 ℃ to prepare an electron transport layer, and the cathode is made of Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Comparative example 1

A quantum dot light-emitting diode comprises a laminated structure of an anode and a cathode which are oppositely arranged, a quantum dot light-emitting layer arranged between the anode and the cathode, an electron transport layer arranged between the cathode and the quantum dot light-emitting layer, and a hole transport layer arranged between the anode and the quantum dot light-emitting layer, wherein the cathode is arranged on a substrate. The material of the substrate is a glass sheet, the material of the anode is an ITO substrate, the material of the hole transport layer is TFB, the material of the electron transport layer is commercial ZnS, and the material of the cathode is Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Comparative example 2

A quantum dot light-emitting diode comprises a laminated structure of an anode and a cathode which are oppositely arranged, a quantum dot light-emitting layer arranged between the anode and the cathode, an electron transport layer arranged between the cathode and the quantum dot light-emitting layer, and a hole transport layer arranged between the anode and the quantum dot light-emitting layer, wherein the cathode is arranged on a substrate. The substrate is made of a glass sheet, the anode is made of an ITO (indium tin oxide) substrate, the hole transport layer is made of a TFB (thin film transistor), the electron transport layer is made of a commercial ZnO material, and the cathode is made of Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Comparative example 3

A quantum dot light emitting diode comprises a laminated structure of an anode and a cathode which are oppositely arranged, a quantum dot light emitting layer arranged between the anode and the cathode, and a quantum dot light emitting layer arranged between the cathode and the cathodeThe electron transport layer between the quantum dot light emitting layers is arranged on the anode, the hole transport layer between the quantum dot light emitting layers is arranged on the cathode, and the cathode is arranged on the substrate. Wherein the substrate is made of glass sheet, the anode is made of ITO substrate, the hole transport layer is made of TFB, and the electron transport layer is made of commercial TiO₂The material of the cathode is Al; with blue light quantum dot Cd_XZn_1-XS/ZnS is used as a material of the luminescent layer, wherein X is more than 0 and less than 1.

Furthermore, in order to verify the advancement of the electron transport film and the quantum dot light emitting diode prepared by the embodiment of the invention, the embodiment of the invention is subjected to performance test.

Test example 1

The test example of the invention performs performance tests on the electron transport films prepared in examples 1 to 3, the electron transport films prepared in comparative examples 1 to 3, the quantum dot light-emitting diodes prepared in examples 4 to 9 and comparative examples 1 to 3, and the test indexes and the test methods are as follows:

(1) electron mobility: testing the current density (J) -voltage (V) of the quantum dot light-emitting diode, drawing a curve relation diagram, fitting a Space Charge Limited Current (SCLC) region in the relation diagram, and then calculating the electron mobility according to a well-known Child's law formula:

J＝(9/8)ε_rε₀μ_eV²/d³(ii) a Wherein J represents current density in mAcm^-2；ε_rDenotes the relative dielectric constant,. epsilon₀Represents the vacuum dielectric constant; mu.s_eDenotes the electron mobility in cm²V^-1s^-1(ii) a V represents the drive voltage, in units of V; d represents the film thickness in m.

(2) Resistivity: the resistivity of the electron transport film is measured by the same resistivity measuring instrument.

(3) External Quantum Efficiency (EQE): measured using an EQE optical test instrument.

Note: the electron mobility and resistivity were tested as single layer thin film structure devices, namely: cathode/electron transport film/anode. The external quantum efficiency test is the QLED device, namely: anode/hole transport film/quantum dot/electron transport film/cathode, or cathode/electron transport film/quantum dot/hole transport film/anode.

The test results are shown in table 1 below:

TABLE 1

From the above test results, it can be seen that the electron transport films of the halogenated graphdiyne doped metal compound prepared in examples 1 to 3 of the present invention have a resistivity significantly lower than that of the electron transport films made of the metal compound nanomaterial in comparative examples 1 to 3, and have an electron mobility significantly higher than that of the electron transport films made of the metal compound nanomaterial in comparative examples 1 to 3.

The external quantum efficiency of the quantum dot light-emitting diodes (the electron transport layer is made of halogenated graphite alkyne doped metal compound) prepared in the embodiments 4 to 9 of the invention is obviously higher than that of the quantum dot light-emitting diodes made of metal compound nano material in the comparative examples 1 to 3, which shows that the quantum dot light-emitting diodes obtained in the embodiments 4 to 9 have better luminous efficiency.

It is noted that the embodiments provided by the present invention all use blue light quantum dots Cd_XZn_1-XS/ZnS is used as a material of a light emitting layer, and is based on that a blue light emitting system is a system which uses more (in addition, a light emitting diode based on blue quantum dots is relatively difficult to manufacture, and therefore has a higher reference value), and does not mean that the invention is only used for the blue light emitting system.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.