WO2023051317A1

WO2023051317A1 - Tungsten oxide nanomaterial and preparation method therefor, and optoelectronic device

Info

Publication number: WO2023051317A1
Application number: PCT/CN2022/119906
Authority: WO
Inventors: 徐威
Original assignee: Tcl科技集团股份有限公司
Priority date: 2021-09-30
Filing date: 2022-09-20
Publication date: 2023-04-06
Also published as: CN115893495A

Abstract

Provided are a preparation method for a tungsten oxide nanomaterial, a tungsten oxide nanomaterial and an optoelectronic device. The preparation method comprises: providing tungstic acid; and mixing tungstic acid with a halogenated compound, the halogenated compound being selected from one or more among halogenated acids and halogenated alcohols, and heating and reacting same to obtain a tungsten oxide nanomaterial. The tungsten oxide nanomaterial comprises tungsten oxide nanoparticles and ligands connected to surfaces of the tungsten oxide nanoparticles, and the ligands comprise one or more among haloacid ligands and halohydrin ligands. The optoelectronic device comprises: an anode, a hole function layer, a light emitting layer and a cathode which are stacked, wherein the hole function layer comprises the tungsten oxide nanomaterial. The tungsten oxide nanomaterial has high hole mobility, which may improve the hole injection and transport capabilities of the optoelectronic device, thereby improving the charge balance in the optoelectronic device, and thus improving the external quantum efficiency and service life of the optoelectronic device.

Description

Tungsten oxide nanomaterial and its preparation method, optoelectronic device

This application claims the priority of the Chinese patent application with the application number 202111160505.0 and the application name "tungsten oxide nanomaterial and its preparation method, hole function thin film and optoelectronic device" filed at the China Patent Office on September 30, 2021 , the entire contents of which are incorporated in this application by reference.

technical field

The present application relates to the field of display technology, and in particular to a preparation method of tungsten oxide nanomaterials, tungsten oxide nanomaterials prepared by the preparation method, and photoelectric devices.

Background technique

Optoelectronic devices refer to devices made according to the photoelectric effect, which have a wide range of applications in new energy, sensing, communication, display, lighting and other fields, such as solar cells, photodetectors, electroluminescent devices, etc.

At present, the light-emitting elements of the display panels of electronic products such as computers and mobile phones are mainly electroluminescent devices. The existing widely used electroluminescent devices are mainly organic electroluminescent devices (OLEDs) and quantum dot electroluminescent devices (QLEDs). The structure of a traditional electroluminescent device mainly includes an anode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer and a cathode. Under the action of the electric field, the holes generated by the anode of the electroluminescent device and the electrons generated by the cathode move, inject into the hole transport layer and the electron transport layer respectively, and finally migrate to the light-emitting layer. When the two meet in the light-emitting layer , to generate energy excitons, thereby exciting the luminescent molecules and finally producing visible light.

It is well known that the electron-hole injection balance of electroluminescent devices can effectively improve the efficiency and lifetime of electroluminescent devices. However, existing electroluminescent devices have poor hole injection and/or transport capabilities due to various reasons, resulting in an unbalanced electron-hole injection of the electroluminescent device. For example, in order to increase the aperture ratio of the display panel, top-emitting electroluminescent devices are generally used. The optical design of top-emitting electroluminescent devices usually requires increasing the thickness of the hole injection layer of the electroluminescent device to optimize the cavity length of the device, and the increase in the thickness of the hole injection layer of the electroluminescent device will lead to The hole injection capability of the electroluminescent device is reduced, which makes the electron-hole injection in the electroluminescent device unbalanced, resulting in low efficiency and life of the electroluminescent device.

Since inorganic materials can effectively solve the problem of device performance degradation due to water absorption in organic materials, in recent years, the use of inorganic semiconductor materials as hole injection materials and hole transport materials has become a relatively popular technology in the preparation of electroluminescent devices. One of the most popular research topics. Among them, tungsten oxide (WO ₃ ), with a band gap of 2.6-2.8eV, can absorb blue light in sunlight, and has good chemical stability, adjustable W/O stoichiometry, adjustable energy level structure, and Due to its high mobility and low price, it is used as a hole injection material or a hole transport material.

technical problem

The hole injection performance of WO ₃ prepared by the existing preparation method is poor, so that the electron-hole injection in the electroluminescent device is unbalanced, resulting in low efficiency and life of the electroluminescent device.

technical solution

Therefore, the present application provides a tungsten oxide nanomaterial, a preparation method thereof, and a photoelectric device.

The embodiment of the present application provides a method for preparing tungsten oxide nanomaterials, which includes the following steps:

Provide tungstic acid;

The tungstic acid is mixed with a halogenated compound, wherein the halogenated compound is selected from one or more of halogenated acids and halogenated alcohols, and heated to react to obtain tungsten oxide nanomaterials, and the tungsten oxide nanomaterials It includes tungsten oxide nanoparticles and ligands connected on the surface of the tungsten oxide nanoparticles, and the ligands include one or more of haloacid ligands and halohydrin ligands.

Preferably, the temperature range of the heating reaction is 40-80°C, and the heating reaction time is 48-72h.

Preferably, the range of the mass ratio of the tungstic acid to the halogenated compound is (1.0:1)-(9.1:1).

Preferably, the preparation method of the tungstic acid is as follows: mixing tungstate and acid to react to obtain tungstic acid.

Preferably, the tungstate is selected from one or more of sodium tungstate, titanium tungstate, nickel tungstate and magnesium tungstate.

Preferably, the tungstate includes one or more of titanium tungstate, nickel tungstate and magnesium tungstate, and the tungsten oxide nanoparticles are doped with doping metal elements, and the doping metal elements are selected from One or more of Ti, Ni and Mg.

Preferably, the molar amount of the doping metal element is 1-20% of the molar amount of the tungsten oxide.

Preferably, after the tungstic acid is mixed with the halogenated compound, a step of adding a weak base is also included.

Preferably, the weak base is selected from one or more of K ₂ CO ₃ , KHCO ₃ , Na ₂ CO ₃ and NaHCO ₃ .

Preferably, the range of the molar ratio of the tungstic acid to the weak base is (1:1.1)-(1:1.5).

Preferably, the halogenated acid is halogenated acetic acid, and the halogenated alcohol is halogenated alcohol.

Preferably, the halogenated acetic acid is selected from one or more of monochlorinated acetic acid, dichlorinated acetic acid and trichloroacetic acid, and the described halogenated alcohol is selected from monochlorinated ethanol, dichlorinated ethanol and trichloroacetic acid One or more of chloroethanols.

Correspondingly, the present application also provides a tungsten oxide nanomaterial, wherein the tungsten oxide nanomaterial includes tungsten oxide nanoparticles and ligands attached to the surface of the tungsten oxide nanoparticles, and the ligands include halogenated acid ligands. One or more of ligands and halohydrin ligands.

Preferably, in the tungsten oxide nanomaterial, the content of the ligand is in the range of 10-50wt%.

Preferably, the tungsten oxide nanoparticles are doped with doping metal elements.

Preferably, the doping metal element is selected from one or more of Ti, Ni and Mg.

Preferably, the average particle diameter of the tungsten oxide nanoparticles is 8-15nm.

Preferably, the haloacid in the haloacid ligand is haloacetic acid, and the halohydrin in the halohydrin ligand is haloethanol.

Correspondingly, the present application also provides a photoelectric device, including a stacked anode, a hole functional layer, a light-emitting layer, and a cathode, wherein the hole functional layer includes the aforementioned tungsten oxide nanomaterial.

Preferably, the anode is selected from doped metal oxide electrodes or composite electrodes, and the doped metal oxide electrodes are selected from indium-doped tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide, aluminum-doped tin oxide One or more of zinc, gallium doped zinc oxide, indium doped zinc oxide, magnesium doped zinc oxide and aluminum doped magnesium oxide, the composite electrode is selected from AZO/Ag/AZO, AZO/Al/AZO , ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO ₂ /Ag/TiO ₂ , TiO ₂ /Al/TiO ₂ , ZnS/Ag/ZnS or ZnS/Al /ZnS;

The light-emitting layer is an organic light-emitting layer or a quantum dot light-emitting layer, and the material of the organic light-emitting layer is selected from 4,4'-bis(N-carbazole)-1,1'-biphenyl:tri[2-(p Tolyl)pyridine-C2,N)Iridium(III), 4,4',4"-tri(carbazol-9-yl)triphenylamine: Tris[2-(p-tolyl)pyridine-C2,N) One or more of iridium(III), diarylanthracene derivatives, stilbene aromatic derivatives, pyrene derivatives, fluorene derivatives, TBPe fluorescent materials, TTPA fluorescent materials, TBRb fluorescent materials, and DBP fluorescent materials multiple, the material of the quantum dot light-emitting layer is selected from one or more of single-structure quantum dots and core-shell structure quantum dots, and the single-structure quantum dots are selected from II-VI group compounds and III-V group compounds And one or more of I-III-VI group compounds, the II-VI group compound is selected from CdSe, CdS, CdTe, ZnSe, ZnS, CdTe, ZnTe, CdZnS, CdZnSe, CdZnTe, ZnSeS, ZnSeTe, ZnTeS , CdSeS, CdSeTe, CdTeS, CdZnSeTe and CdZnSTe one or more, the III-V compound is selected from InP, InAs, GaP, GaAs, GaSb, AlN, AlP, InAsP, InNP, InNSb, GaAlNP and InAlNP One or more of them, the I-III-VI group compound is selected from one or more of CuInS ₂ , CuInSe ₂ and AgInS ₂ , and the quantum dots of the core-shell structure are selected from CdSe/ZnS, CdSe One or more of /ZnSe/ZnS, ZnCdSe/ZnSe/ZnS, ZnSe/ZnS, ZnSeTe/ZnS, CdSe/CdZnSeS/ZnS, InP/ZnSe/ZnS and InP/ZnSeS/ZnS;

The cathode is selected from one or more of Ag electrodes, Al electrodes, Au electrodes, Pt electrodes, Ag/IZO electrodes, IZO electrodes or alloy electrodes.

Beneficial effect

The tungsten oxide nanomaterial prepared by the preparation method of the tungsten oxide nanomaterial of the present application includes tungsten oxide nanoparticles and one or more of the haloacid ligands and the halohydrin ligands attached to the surface of the tungsten oxide nanoparticles. kind. The haloacid ligand and the halohydrin ligand can effectively passivate the defect state luminescence of tungsten oxide nanoparticles, improve the dispersibility and stability of tungsten oxide nanoparticles in solvents, and improve the The hole mobility of the hole functional layer can improve the hole injection and transport capabilities of optoelectronic devices, thereby improving the charge balance in optoelectronic devices, thereby improving the external quantum efficiency and life of optoelectronic devices.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

Fig. 1 is a flow chart of a preparation method of a tungsten oxide nanomaterial provided in an embodiment of the present application;

Fig. 2 is a schematic structural diagram of an optoelectronic device provided by an embodiment of the present application;

Fig. 3 is a schematic structural diagram of another optoelectronic device provided by the embodiment of the present application;

Fig. 4 is a schematic structural diagram of another optoelectronic device provided by an embodiment of the present application.

Embodiment of this application

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of this application.

Embodiments of the present application provide a tungsten oxide nanomaterial, a preparation method thereof, and an optoelectronic device. Each will be described in detail below. It should be noted that the description sequence of the following embodiments is not intended to limit the preferred sequence of the embodiments. In addition, in the description of the present application, the term "including" means "including but not limited to".

In this application, expressions such as "one or more" refer to one or more of the listed items, and "multiple" refers to any combination of two or more of these items, including single items (species) ) or any combination of plural items (species), for example, "at least one (species) of a, b, or c" or "at least one (species) of a, b, and c" can mean: a ,b,c,a-b (that is, a and b),a-c,b-c, or a-b-c, where a,b,c can be single or multiple.

Various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be construed as a rigid limitation on the scope of the application; therefore, the described range should be regarded as The description has specifically disclosed all possible subranges as well as individual values within that range. For example, a description of a range from 1 to 6 should be considered to have specifically disclosed subranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and Single numbers within the stated ranges, eg 1, 2, 3, 4, 5 and 6, apply regardless of the range. Additionally, whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range.

Please refer to Figure 1, the embodiment of this application provides a preparation method of tungsten oxide nanomaterials, including the following steps:

Step S11: providing tungstic acid;

Step S12: Mix tungstic acid with a halogenated compound, the halogenated compound includes one or more of halogenated acid and halogenated alcohol; heat the reaction to obtain tungsten oxide nanomaterials, and the tungsten oxide nanomaterials include oxidized Tungsten nanoparticles and ligands connected to the surface of the tungsten oxide nanoparticles, the ligands include one or more of haloacid ligands and halohydrin ligands.

In the step S11:

The tungstic acid may be selected from but not limited to one or more of white tungstic acid, yellow tungstic acid and metatungstic acid.

In one embodiment, the tungstic acid is produced by the following method: mixing tungstate with acid and reacting to obtain tungstic acid.

The tungstate can be selected from but not limited to sodium tungstate (Na ₂ WO ₄ ), titanium tungstate (TiW ₂ O ₅ ), nickel tungstate (NiW ₂ O ₅ ) and magnesium tungstate (MgWO ₄ ). one or more. The sodium tungstate can be sodium tungstate dihydrate (Na ₂ WO ₄ ·2H ₂ O), the titanium tungstate can be titanium tungstate hexahydrate (TiW ₂ O ₅ ·2H ₂ O), the tungstate The nickel may be nickel tungstate hexahydrate (NiW ₂ O ₅ ·2H ₂ O), and the magnesium tungstate may be magnesium tungstate dihydrate (MgWO ₄ ·2H ₂ O).

When the tungstate includes one or more of titanium tungstate, nickel tungstate and magnesium tungstate, the prepared tungstate will contain one or more of metal elements such as Ti, Ni and Mg. Various. Correspondingly, the tungsten oxide nanoparticles in the tungsten oxide nanomaterials prepared in step S14 are metal element-doped tungsten oxide nanoparticles, and the tungsten oxide nanomaterials include metal element-doped tungsten oxide nanoparticles and connecting haloacid ligands and/or halohydrin ligands on the surface of the tungsten oxide nanoparticles. The doping metal elements include but not limited to one or more of Ti, Ni and Mg.

The acid is an acid commonly used in the preparation of tungstic acid, for example, it can be selected from but not limited to one or more of nitric acid and hydrochloric acid. In one embodiment, the acid is 10% nitric acid in water.

In some embodiments, the preparation method of white tungstic acid further includes the step of cleaning the tungstic acid with a cleaning agent. It can be understood that the cleaning agent can be isopropanol, cyclohexane, ethanol, etc. that are conventionally used for cleaning tungstic acid.

In the step S12:

The halogenated acid refers to a compound containing both a halogen atom and a carboxyl group in the molecule. The halogen atom may be selected from but not limited to one or more of fluorine (F), chlorine (Cl), bromine (Br) and iodine (I). In some embodiments, the haloacid is the haloacetic acid. As an example, the haloacid is selected from monochlorinated acetic acid (CH ₂ ClCOOH), dichlorinated acetic acid (CHCl ₂ COOH) and trichloroacetic acid. One or more of acetic acid (CCl ₃ COOH).

The halogenated alcohol refers to a compound containing both a halogen atom and a -CH ₂ -OH group in the molecule. The halogen atom may be selected from but not limited to one or more of fluorine (F), chlorine (Cl), bromine (Br) and iodine (I). In some embodiments, the halogenated alcohol is the halogenated alcohol. As an example, the halogenated alcohol is selected from monochlorinated ethanol (CH ₂ ClCH ₂ OH), dichlorinated alcohol (CHCl ₂ CH ₂ OH ) and one or more of trichloroethanol (CCl ₃ CH ₂ OH).

In some embodiments, the mass ratio of the tungstic acid to the haloacid and/or halohydrin ranges from (1.0:1) to (9.1:1).

In some embodiments, the method of mixing tungstic acid and halogenated compound is ultrasonic, so that tungstic acid is uniformly dispersed in the halogenated acid and/or halogenated alcohol.

In some embodiments, after the tungstic acid is mixed with the halogenated acid and/or the halogenated alcohol, a weak base needs to be added to adjust the pH value of the solution to 6-8, thereby promoting the reaction between the tungstic acid and the halogenated compound. Form a coordination bond. The weak base may be selected from but not limited to one or more of K ₂ CO ₃ , KHCO ₃ , Na ₂ CO ₃ and NaHCO ₃ . In one embodiment, the weak base is an aqueous solution of a weak base, and the content of the weak base in the aqueous solution of the weak base is 10-30 wt%.

In some embodiments, the molar ratio of the tungstic acid to the weak base is in the range of (1:1.1)-(1:1.5).

In some embodiments, the temperature range of the heating is 40-80°C. The reaction time is 48-72h. It can be understood that, in order to make the reaction proceed quickly and fully, the reaction can be carried out under stirring.

In some embodiments, in the tungsten oxide nanomaterial, the content of the ligand is in the range of 10-50wt%. If the ligand content is too low, the defect state luminescence of the tungsten oxide nanoparticles cannot be effectively passivated; if the ligand content is too high, the conductivity of the tungsten oxide nanomaterials will be too low.

The average particle diameter of the tungsten oxide nanoparticles is 8-15nm. If the particle size of the tungsten oxide nanoparticles is too small, the electrical conductivity is poor and unstable; The energy level mismatch will cause difficulty in carrier injection.

In some embodiments, the tungsten oxide nanoparticles may be doped with doping metal elements, in other words, the tungsten oxide nanoparticles are tungsten oxide nanoparticles doped with metal elements. The doping metal element may be selected from but not limited to one or more of Ti, Ni and Mg. The metal element doping can effectively improve the hole concentration and hole mobility of the tungsten oxide nanomaterial.

In the tungsten oxide nanomaterial, the molar amount of the doping metal element is 1-20% of that of the tungsten oxide. If the content of the doping metal element is too low, there will be no doping effect, and if the content is too high, the doping metal element will be crystallized separately.

The tungsten oxide nanomaterial prepared by the preparation method of the tungsten oxide nanomaterial comprises tungsten oxide nanoparticles and one or more of halogenated acid ligands and halogenated alcohol ligands attached to the surface of the tungsten oxide nanoparticles . The haloacid ligand and the halohydrin ligand can effectively passivate the defect state luminescence of tungsten oxide nanoparticles, improve the dispersibility and stability of tungsten oxide nanoparticles in solvents, and improve the The hole mobility of the hole functional layer can improve the hole injection and transport capabilities of optoelectronic devices, thereby improving the charge balance in optoelectronic devices, thereby improving the external quantum efficiency and life of optoelectronic devices.

The embodiment of the present application also provides a hole-functional thin film, and the hole-functional thin film may be a hole injection thin film or a hole transport thin film. The hole function thin film includes the tungsten oxide nanomaterial.

The embodiment of the present application also provides a method for preparing the hole function thin film, comprising the following steps:

Step S21: providing the tungsten oxide nanomaterial;

Step S22: disposing the tungsten oxide nanomaterial on the substrate to form a thin film of the tungsten oxide nanomaterial, that is, to obtain a hole-energy film.

It can be understood that the type of the substrate is not limited. In an embodiment, the substrate is an anode substrate, and the substrate may be a conventionally used substrate such as glass, and the tungsten oxide nanomaterial is disposed on the anode. In yet another embodiment, the substrate includes a stacked cathode and a light-emitting layer, and the tungsten oxide nanomaterial is disposed on the light-emitting layer.

In the step S22, the method of disposing the tungsten oxide nanomaterial on the substrate may be a chemical method or a physical method. Among them, the chemical method can be chemical vapor deposition method, continuous ion layer adsorption and reaction method, anodic oxidation method, electrolytic deposition method and co-precipitation method, etc. The physical method can be physical coating method or solution processing method, and the physical coating method can be thermal evaporation coating method CVD, electron beam evaporation coating method, magnetron sputtering method, multi-arc ion coating method, physical vapor deposition method PVD, atomic layer deposition method and pulse laser deposition method, etc.; the solution processing method can be spin coating method, printing method, inkjet printing method, scraping method, printing method, dipping and pulling method, soaking method, spraying method, roller coating method, casting method, Slot coating method and strip coating method, etc.

In one embodiment, the method of disposing the tungsten oxide nanomaterial on the substrate is a solution method, at this time, the tungsten oxide nanomaterial needs to be dispersed with a dispersant to obtain a tungsten oxide nanomaterial dispersion, Then the tungsten oxide nanomaterial dispersion is disposed on the substrate by a solution method. The dispersant may be selected from but not limited to one or more of methanol, ethanol, butanol and pentanol. In one embodiment, the concentration range of the dispersion is 5-40 mg/mL.

Referring to FIGS. 2-4 , the embodiment of the present application also provides an optoelectronic device 100 , and the optoelectronic device 100 may be a solar cell, a photodetector, an organic optoelectronic device (OLED) or a quantum dot optoelectronic device (QLED). The optoelectronic device 100 includes an anode 10 , a hole functional layer 20 , a light emitting layer 30 and a cathode 40 which are sequentially stacked. The hole functional layer 20 includes one or more of a hole injection layer 21 and a hole transport layer 22 . The hole injection layer 21 and/or the hole transport layer 22 is the hole energy film, in other words, the hole injection layer 21 and/or the hole transport layer 22 includes the oxide Tungsten nanomaterials.

Referring to FIG. 2 , in one embodiment, the optoelectronic device 100 includes an anode 10 , a hole injection layer 21 , a light emitting layer 30 and a cathode 40 which are sequentially stacked. The hole injection layer 21 includes the tungsten oxide nanomaterial.

Please refer to FIG. 3 , in another embodiment, the optoelectronic device 100 includes an anode 10 , a hole transport layer 22 , a light emitting layer 30 and a cathode 40 which are sequentially stacked. The hole transport layer 22 includes the tungsten oxide nanomaterial.

Please refer to FIG. 4 , in yet another embodiment, the optoelectronic device 100 includes an anode 10 , a hole injection layer 21 , a hole transport layer 22 , a light emitting layer 30 and a cathode 40 which are sequentially stacked. The hole injection layer 21 and/or the hole transport layer 22 includes the tungsten oxide nanomaterial.

The material of the anode 10 is known in the art for anode materials, for example, can be selected from but not limited to doped metal oxide electrodes, composite electrodes and the like. The doped metal oxide electrode may be selected from but not limited to indium doped tin oxide (ITO), fluorine doped tin oxide (FTO), antimony doped tin oxide (ATO), aluminum doped zinc oxide (AZO), One or more of gallium-doped zinc oxide (GZO), indium-doped zinc oxide (IZO), magnesium-doped zinc oxide (MZO) and aluminum-doped magnesium oxide (AMO). The composite electrode is a composite electrode with a metal layer sandwiched between doped or non-doped transparent metal oxide layers, such as AZO/Ag/AZO, AZO/Al/AZO, ITO/Ag/ITO, ITO/Al/ ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO ₂ /Ag/TiO ₂ , TiO ₂ /Al/TiO ₂ , ZnS/Ag/ZnS, ZnS/Al/ZnS, etc. Wherein, "/" indicates a laminated structure, for example, AZO/Ag/AZO indicates a composite electrode with a laminated structure formed by sequentially laminating an AZO layer, an Ag layer and an AZO layer.

The light emitting layer 30 may be an organic light emitting layer or a quantum dot light emitting layer. When the light emitting layer 30 is an organic light emitting layer, the optoelectronic device 100 may be an organic optoelectronic device. When the light emitting layer 30 is a quantum dot light emitting layer, the optoelectronic device 100 may be a quantum dot optoelectronic device.

The material of the organic light-emitting layer is a material known in the art for the organic light-emitting layer of optoelectronic devices, for example, can be selected from but not limited to CBP:Ir(mppy)3(4,4'-bis(N-carbazole )-1,1'-biphenyl: Tris[2-(p-tolyl)pyridine-C2,N) iridium(III)), TCTA:Ir(mmpy)(4,4',4"-tri(carba Azol-9-yl)triphenylamine: tris[2-(p-tolyl)pyridine-C2,N)iridium(III)), diarylanthracene derivatives, stilbene aromatic derivatives, pyrene derivatives or One or more of fluorene derivatives, TBPe fluorescent material emitting blue light, TTPA fluorescent material emitting green light, TBRb fluorescent material emitting orange light, and DBP fluorescent material emitting red light.

The material of the quantum dot light-emitting layer is a quantum dot material known in the art for the quantum dot light-emitting layer of an optoelectronic device, for example, it can be selected from but not limited to one or more of a single-structure quantum dot and a core-shell structure quantum dot Various. For example, the single-structure quantum dots may be selected from, but not limited to, one or more of II-VI compounds, III-V compounds, and I-III-VI compounds. As an example, the II-VI group compound can be selected from but not limited to CdSe, CdS, CdTe, ZnSe, ZnS, CdTe, ZnTe, CdZnS, CdZnSe, CdZnTe, ZnSeS, ZnSeTe, ZnTeS, CdSeS, CdSeTe, CdTeS, CdZnSeTe and One or more of CdZnSTe; the III-V compound can be selected from but not limited to one or Various; the I-III-VI compound may be selected from but not limited to one or more of CuInS ₂ , CuInSe ₂ and AgInS ₂ . The quantum dots of the core-shell structure can be selected from but not limited to CdSe/ZnS, CdSe/ZnSe/ZnS, ZnCdSe/ZnSe/ZnS, ZnSe/ZnS, ZnSeTe/ZnS, CdSe/CdZnSeS/ZnS, InP/ZnSe/ZnS and One or more of InP/ZnSeS/ZnS.

The cathode 40 is a cathode known in the art for optoelectronic devices, for example, can be selected from but not limited to Ag electrodes, Al electrodes, Au electrodes, Pt electrodes, Ag/IZO electrodes, IZO electrodes or alloy electrodes or one of them. Various. Among them, the Ag/IZO electrode refers to a composite electrode having a laminated structure formed by laminating an Ag layer and an IZO layer.

In one embodiment, the optoelectronic device 100 further includes an electron transport layer, and the electron transport layer is connected between the light emitting layer 30 and the cathode 40 .

The material of the electron transport layer is a material known in the art for the electron transport layer, for example, can be selected from but not limited to ZnO, TiO ₂ , ZrO ₂ , HfO ₂ , Ca, Ba, CsF, LiF, CsCO ₃ , One or more of ZnMgO, PBD (2-(4-biphenyl)-5-phenyloxadiazole), 8-hydroxyquinoline aluminum (Alq3) and graphene.

When the photoelectric device 100 includes a hole injection layer 21 and a hole transport layer 22 at the same time, and only the hole injection layer 21 includes the tungsten oxide nanomaterial, the material of the hole transport layer 22 can be known in the art. Known materials for the hole transport layer, for example, can be selected from but not limited to poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), 2,2' ,7,7'-tetra[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (spiro-omeTAD), 4,4'-cyclohexylbis[N, N-bis(4-methylphenyl)aniline](TAPC), N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-diphenyl-4, 4'-diamine (NPB), 4,4'-bis(N-carbazole)-1,1'-biphenyl (CBP), poly[(9,9-dioctylfluorenyl-2,7- Diyl)-co-(4,4'-(N-(p-butylphenyl))diphenylamine)] (TFB), poly(9-vinylcarbazole) (PVK), polytriphenylamine (Poly- TPD), poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) (PEDOT:PSS) and 4,4',4"-tris(carbazol-9-yl)triphenylamine ( TCTA) in one or more.

When the photoelectric device 100 includes a hole injection layer 21 and a hole transport layer 22 at the same time, and only the hole transport layer 22 includes the tungsten oxide nanomaterial, the material of the hole injection layer 21 is known in the art The material used for the hole injection layer, for example, can be selected from but not limited to 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene One or more of (HAT-CN), PEDOT:PSS and its derivative doped with s-MoO ₃ (PEDOT:PSS:s-MoO ₃ ).

It can be understood that, in addition to the above-mentioned functional layers, the optoelectronic device 100 can also add some functional layers that are conventionally used in optoelectronic devices to help improve the performance of optoelectronic devices, such as electron blocking layers, hole blocking layers, electron injection layers and Interface modification layer, etc.

It can be understood that the material of each layer of the optoelectronic device 100 can be adjusted according to the light emission requirement of the optoelectronic device 100 .

It can be understood that the optoelectronic device 100 may be a positive optoelectronic device or an inverted optoelectronic device.

The embodiment of the present application also provides a method for preparing the optoelectronic device 100, including the following steps:

Step S31: providing the anode 10;

Step S32: providing the tungsten oxide nanomaterial, and disposing the tungsten oxide nanomaterial on the anode 10 to obtain a hole functional layer 20;

Step S33 : sequentially forming a laminated light-emitting layer 30 and a cathode 40 on the hole functional layer 20 .

It can be understood that when the optoelectronic device 100 further includes an electron transport layer, the step S33 is: sequentially forming a stacked light emitting layer 30 , an electron transport layer and a cathode 40 on the hole functional layer 20 .

The embodiment of the present application also provides another method for preparing the optoelectronic device 100, which includes the following steps:

Step S41: providing a cathode 40, and forming a light-emitting layer 30 on the cathode 40;

Step S42: providing the tungsten oxide nanomaterial, and disposing the tungsten oxide nanomaterial on the light-emitting layer 30 to obtain the hole functional layer 20;

Step S43 : forming the anode 10 on the hole functional layer 20 .

It can be understood that when the optoelectronic device 100 further includes an electron transport layer, the step S41 is: providing a cathode 40 , and sequentially forming a laminated electron transport layer and a light emitting layer 30 on the cathode 40 .

In the above two preparation methods:

The method for forming the anode 10, the light-emitting layer 30, the electron transport layer and the cathode 40 can be realized by conventional techniques in the art, such as chemical or physical methods. The chemical method or physical method can be referred to above, and will not be repeated here.

It can be understood that when the photoelectric device 100 further includes other functional layers such as an electron blocking layer, a hole blocking layer, an electron injection layer and/or an interface modification layer, the preparation method of the photoelectric device 100 also includes forming the functional layer layer steps.

The present application will be described in detail through specific examples below, and the following examples are only part of the examples of the present application, and are not intended to limit the present application.

Example 1

An ITO/Ag/ITO composite anode 10 is provided, and the thicknesses of the ITO layer, the Ag layer and the ITO layer stacked in the ITO/Ag/ITO composite anode 10 are respectively 10nm, 100nm, and 10nm;

Spin-coat PEDOT:PSS (model AI4083) material on the anode 10, and then heat-treat at 150° C. for 15 minutes to obtain a hole injection layer 21 with a thickness of 24 nm;

Dissolve 10mmol Na ₂ WO ₄ 2H ₂ O in 100ml deionized water, add 10% HNO ₃ aqueous solution, stir vigorously to obtain off-white H ₂ WO ₄ precipitate, then wash the H ₂ WO ₄ with isopropanol Precipitation: Dissolve the H ₂ WO ₄ precipitate in 150 mL of monochlorinated acetic acid, ultrasonically disperse, add 10 ml of K ₂ CO ₃ aqueous solution with a mass concentration of 10 wt%, stir vigorously for 60 min, and use it after stirring at 50°C for 2 days Centrifugal cleaning with ion water and ethanol to obtain tungsten oxide nanomaterials, the tungsten oxide nanomaterials include tungsten oxide nanoparticles and monochlorinated acetic acid ligands connected to the surface of the tungsten oxide nanoparticles, the monochlorinated acetic acid ligands The content is 20wt%;

Disperse the tungsten oxide nanomaterial in cyclohexane to obtain a tungsten oxide nanomaterial dispersion with a concentration of 20 mg/mL, spin-coat the tungsten oxide nanomaterial dispersion on the hole injection layer 21, and then Heat treatment at 100° C. for 30 minutes to obtain a hole transport layer 22 with a thickness of 24 nm;

Spin-coat CdSe/CdZnSeS/ZnS quantum dot luminescent material on the hole transport layer 22 to obtain a luminescent layer 30 with a thickness of 29 nm;

Spin-coat ZnMgO material on the light-emitting layer 30, wherein the content of Mg in the ZnMgO material is 15wt%, heat treatment at 100° C. for 20 minutes in a nitrogen atmosphere, and obtain an electron transport layer with a thickness of 50 nm;

Evaporating Ag on the electron transport layer to obtain a cathode 40 with a thickness of 40 nm;

The NPB material was vapor-deposited on the cathode 40 to obtain a covering layer with a thickness of 60 nm, and the photoelectric device 100 was obtained. The optoelectronic device 100 of this embodiment is a quantum dot optoelectronic device.

Example 2

This example is basically the same as Example 1, the difference is that in this example, 8mmol Na ₂ WO ₄ 2H ₂ O and 1mmol TiW ₂ O ₅ 6H ₂ O were dissolved in 100ml deionized water, correspondingly, the obtained oxidation The tungsten nano material comprises Ti-doped tungsten oxide nanoparticles and monochlorinated acetic acid ligands connected on the surface of the tungsten oxide nanoparticles. Wherein, the molar amount of Ti is 10% of the molar amount of W.

Example 3

This example is basically the same as Example 1, the difference is that in this example, 8mmol Na ₂ WO ₄ 2H ₂ O and 1mmol NiW ₂ O ₅ 6H ₂ O were dissolved in 100ml deionized water, correspondingly, the obtained oxidation The tungsten nano material comprises Ni-doped tungsten oxide nanoparticles and monochlorinated acetic acid ligands connected on the surface of the tungsten oxide nanoparticles. Wherein, the molar amount of Ni is 10% of the molar amount of W.

Example 4

This example is basically the same as Example 1, the difference is that in this example, 8mmol Na ₂ WO ₄ 2H ₂ O and 2mmol MgWO ₄ 2H ₂ O were dissolved in 100ml deionized water, correspondingly, the obtained tungsten oxide nano The materials include Mg-doped tungsten oxide nanoparticles and monochlorinated acetic acid ligands connected on the surface of the tungsten oxide nanoparticles. Wherein, the molar amount of Mg is 20% of the molar amount of W.

Example 5

This example is basically the same as Example 1, except that 8.5mmol Na ₂ WO ₄ 2H ₂ O, 0.5mmol NiW ₂ O ₅ 6H ₂ O and 0.5mmol MgWO ₄ 2H ₂ O were dissolved in In 100ml of deionized water, correspondingly, the obtained tungsten oxide nanomaterials include Ni and Mg doped tungsten oxide nanoparticles and acetic acid monochloride ligands attached to the surface of the tungsten oxide nanoparticles. Wherein, the molar amount of Ni is 5% of the molar amount of W, and the molar amount of Mg is 5% of the molar amount of W.

Example 6

This example is basically the same as Example 1, the difference is that in this example, 8.5mmol Na ₂ WO ₄ ·2H ₂ O, 0.5mmol TiW ₂ O ₅ ·6H ₂ O and 0.5mmol MgWO ₄ ·2H ₂ O were dissolved in 100ml of deionized water, correspondingly, the obtained tungsten oxide nanomaterials include Ti and Mg doped tungsten oxide nanoparticles and acetic acid monochloride ligands attached to the surface of the tungsten oxide nanoparticles. Wherein, the molar weight of Ti is 5% of the molar weight of W, and the molar weight of Mg is 5% of the molar weight of W.

Example 7

This example is basically the same as Example 1, the difference is that the H ₂ WO ₄ precipitate is dissolved in 150 mL of dichlorinated ethanol, and correspondingly, the obtained tungsten oxide nanomaterials include tungsten oxide nanoparticles and tungsten oxide nanoparticles connected to the Ethanol dichloride ligands on the surface of tungsten oxide nanoparticles.

Example 8

Dissolve 10mmol Na ₂ WO ₄ 2H ₂ O in 100ml deionized water, add 10% HNO ₃ aqueous solution, stir vigorously to obtain off-white H ₂ WO ₄ precipitate, then wash the H ₂ WO ₄ with isopropanol Precipitation: Dissolve the H ₂ WO ₄ precipitate in 150 mL of trichloroacetic acid, ultrasonically disperse, add 10 ml of K ₂ CO ₃ aqueous solution with a mass concentration of 10 wt%, stir vigorously for 60 min, and use it after stirring at 50°C for 2 days Centrifugal cleaning with ion water and ethanol to obtain tungsten oxide nanomaterials, the tungsten oxide nanomaterials include tungsten oxide nanoparticles and trichloroacetic acid ligands connected to the surface of the tungsten oxide nanoparticles, the trichloroacetic acid ligands The content is 60wt%;

Dispersing the tungsten oxide nanomaterial in cyclohexane to obtain a tungsten oxide nanomaterial dispersion with a concentration of 20 mg/mL, spin-coating the tungsten oxide nanomaterial dispersion on the anode 10, and then heat-treating at 100°C 30min to obtain a hole injection layer 21 with a thickness of 24nm;

Spin-coat TFB material on the hole injection layer 21 to obtain a hole transport layer 22 with a thickness of 24 nm;

Spin-coat CBP:Ir(mppy)3 material on the hole transport layer 22 to obtain a light-emitting layer 30 with a thickness of 29nm;

Spin-coat PBD material on the light-emitting layer 30, and heat-treat at 150° C. for 30 minutes in a nitrogen atmosphere to obtain an electron transport layer with a thickness of 50 nm;

Evaporating Ag and IZO sequentially on the electron transport layer to obtain an Ag/IZO cathode 40 with a thickness of 40 nm;

The NPB material was vapor-deposited on the cathode 40 to obtain a covering layer with a thickness of 60 nm, and the photoelectric device 100 was obtained. The optoelectronic device 100 of this embodiment is an organic optoelectronic device.

Comparative example 1

This comparative example is basically the same as Example 1, except that the material of the hole transport 22 in this comparative example is TFB.

Comparative example 2

This comparative example is basically the same as Example 8, except that the material of the hole injection layer 21 in this comparative example is PEDOT:PSS (model: AI4083).

The external quantum efficiency EQE and lifetime T95_1knit tests were performed on the optoelectronic devices of Examples 1-8 and Comparative Examples 1-2. Among them, the external quantum efficiency EQE is measured by EQE optical testing equipment, and the life test is carried out through the life test box. The life time T95_1knit refers to the time for the quantum dot light-emitting diode to decay to 95% of the initial brightness of 1knit. The test results are shown in Table 1 below.

Table I:

the

External Quantum Efficiency (EQE)/%

T95_1knit service life/h

实施例1Example 1	1515	1200012000
实施例2Example 2	1616	1300013000
实施例3Example 3	1515	1200012000
实施例4Example 4	1717	1300013000
实施例5Example 5	1414	1100011000
实施例6Example 6	1515	1400014000
实施例7Example 7	1616	1500015000
实施例8Example 8	1515	1000010000
对比例1Comparative example 1	1010	20002000
对比例2Comparative example 2	55	30003000

As can be seen from Table 1, the external quantum efficiency and the lifespan of the quantum dot optoelectronic device of embodiment 1-7 are obviously higher than the external quantum efficiency and the life of the quantum dot optoelectronic device of comparative example 1, the external quantum efficiency of the organic optoelectronic device of embodiment 8 The external quantum efficiency and the lifetime of the organic optoelectronic device of Comparative Example 2 are obviously higher than that of the organic optoelectronic device.

The tungsten oxide nanomaterials and their preparation methods and optoelectronic devices provided by the embodiments of the present application have been described in detail above. In this paper, specific examples are used to illustrate the principles and implementation methods of the present application. The descriptions of the above embodiments are only for To help understand the method and its core idea of this application; at the same time, for those skilled in the art, according to the idea of this application, there will be changes in the specific implementation and application scope. In summary, the content of this specification does not It should be understood as a limitation on the application.

Claims

A method for preparing tungsten oxide nanomaterials, comprising the steps of:

Provide tungstic acid;

The tungstic acid is mixed with a halogenated compound, wherein the halogenated compound is selected from one or more of halogenated acids and halogenated alcohols, and heated to react to obtain tungsten oxide nanomaterials, and the tungsten oxide nanomaterials It includes tungsten oxide nanoparticles and ligands connected on the surface of the tungsten oxide nanoparticles, and the ligands include one or more of haloacid ligands and halohydrin ligands.
The preparation method according to claim 1, wherein the temperature range of the heating reaction is 40-80°C, and the heating reaction time is 48-72h.
The preparation method according to claim 1, wherein the range of the mass ratio of the tungstic acid to the halogenated compound is (1.0:1)-(9.1:1).
The preparation method as claimed in claim 3, wherein, the preparation method of the tungstic acid is: mixing tungstate with acid and reacting to obtain tungstic acid.
The preparation method according to claim 4, wherein the tungstate is selected from one or more of sodium tungstate, titanium tungstate, nickel tungstate and magnesium tungstate.
The preparation method according to claim 4, wherein the tungstate comprises one or more of titanium tungstate, nickel tungstate and magnesium tungstate, and the tungsten oxide nanoparticles are doped with doping metal element, the doping metal element is selected from one or more of Ti, Ni and Mg.
The preparation method according to claim 6, wherein the molar amount of the doping metal element is 1-20% of the molar amount of the tungsten oxide.
The preparation method according to claim 1, wherein, after the tungstic acid is mixed with the halogenated compound, it also includes the step of adding a weak base, wherein the weak base is selected from K 2 CO 3 , KHCO 3 , Na One or more of 2 CO 3 and NaHCO 3 .
The preparation method according to claim 8, wherein the molar ratio of the tungstic acid to the weak base is in the range of (1:1.1)-(1:1.5).
The preparation method according to claim 1, wherein the halogenated acid is halogenated acetic acid, and the halogenated alcohol is halogenated alcohol.
The preparation method according to claim 10, wherein, the halogenated acetic acid is selected from one or more of monochlorinated acetic acid, dichlorinated acetic acid and trichloroacetic acid, and the halogenated alcohol is selected from monochloroacetic acid One or more of trichloroethanol, dichloroethanol and trichloroethanol.
A tungsten oxide nanomaterial, wherein the tungsten oxide nanomaterial includes tungsten oxide nanoparticles and ligands connected to the surface of the tungsten oxide nanoparticles, and the ligands include haloacid ligands and halohydrin ligands one or more of.
The tungsten oxide nanomaterial according to claim 12, wherein, in the tungsten oxide nanomaterial, the content of the ligand is in the range of 10-50wt%.
The tungsten oxide nanomaterial according to claim 12, wherein the tungsten oxide nanoparticles are doped with doping metal elements, and the doping metal elements are selected from one or more of Ti, Ni and Mg.
The tungsten oxide nanomaterial according to claim 14, wherein the molar amount of the doping metal element is 1-20% of the molar amount of the tungsten oxide.
The tungsten oxide nanomaterial according to claim 12, wherein the average particle diameter of the tungsten oxide nanoparticles is 8-15nm.
The tungsten oxide nanomaterial according to claim 12, wherein the haloacid in the haloacid ligand is haloacetic acid, and the halohydrin in the halohydrin ligand is haloethanol.
The tungsten oxide nanomaterial according to claim 17, wherein the halogenated acetic acid is selected from one or more of monochlorinated acetic acid, dichlorinated acetic acid and trichloroacetic acid, and the halogenated alcohol is selected from monochloroacetic acid One or more of trichloroethanol, dichloroethanol and trichloroethanol.
A photoelectric device, comprising a stacked anode, a hole functional layer, a light-emitting layer and a cathode, wherein the hole functional layer includes the tungsten oxide nanomaterial according to any one of claims 12-18.
The tungsten oxide nanomaterial according to claim 19, wherein the anode is selected from a doped metal oxide electrode or a composite electrode, and the doped metal oxide electrode is selected from indium-doped tin oxide, fluorine-doped tin oxide , one or more of antimony-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, indium-doped zinc oxide, magnesium-doped zinc oxide and aluminum-doped magnesium oxide, and the composite electrode is selected from AZO/Ag/AZO, AZO/Al/AZO, ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO 2 /Ag/TiO 2 , TiO 2 /Al/TiO 2. ZnS/Ag/ZnS or ZnS/Al/ZnS;

The light-emitting layer is an organic light-emitting layer or a quantum dot light-emitting layer, and the material of the organic light-emitting layer is selected from 4,4'-bis(N-carbazole)-1,1'-biphenyl:tri[2-(p Tolyl)pyridine-C2,N)Iridium(III), 4,4',4"-tri(carbazol-9-yl)triphenylamine: Tris[2-(p-tolyl)pyridine-C2,N) One or more of iridium(III), diarylanthracene derivatives, stilbene aromatic derivatives, pyrene derivatives, fluorene derivatives, TBPe fluorescent materials, TTPA fluorescent materials, TBRb fluorescent materials, and DBP fluorescent materials multiple, the material of the quantum dot light-emitting layer is selected from one or more of single-structure quantum dots and core-shell structure quantum dots, and the single-structure quantum dots are selected from II-VI group compounds and III-V group compounds And one or more of I-III-VI group compounds, the II-VI group compound is selected from CdSe, CdS, CdTe, ZnSe, ZnS, CdTe, ZnTe, CdZnS, CdZnSe, CdZnTe, ZnSeS, ZnSeTe, ZnTeS , CdSeS, CdSeTe, CdTeS, CdZnSeTe and CdZnSTe one or more, the III-V compound is selected from InP, InAs, GaP, GaAs, GaSb, AlN, AlP, InAsP, InNP, InNSb, GaAlNP and InAlNP One or more of them, the I-III-VI group compound is selected from one or more of CuInS 2 , CuInSe 2 and AgInS 2 , and the quantum dots of the core-shell structure are selected from CdSe/ZnS, CdSe One or more of /ZnSe/ZnS, ZnCdSe/ZnSe/ZnS, ZnSe/ZnS, ZnSeTe/ZnS, CdSe/CdZnSeS/ZnS, InP/ZnSe/ZnS and InP/ZnSeS/ZnS;

The cathode is selected from one or more of Ag electrodes, Al electrodes, Au electrodes, Pt electrodes, Ag/IZO electrodes, IZO electrodes or alloy electrodes.