CN115411198A - Light emitting device and method of manufacturing the same - Google Patents

Abstract

The present application provides a light emitting device and a manufacturing method thereof. The light emitting device includes a first electrode layer, an electrode protection layer, a light emitting layer and a second electrode layer. The electrode protection layer is disposed on the first electrode layer. Oxygen absorbing material is dispersed in the electrode protection layer. The light emitting layer is arranged on the side of the electrode protection layer away from the first electrode layer. The second electrode layer is arranged on the side of the light emitting layer away from the electrode protection layer. In this application, an electrode protection layer is formed on the side of the first electrode layer. Oxygen absorbing particles are dispersed in the electrode protection layer. The oxygen absorbing particles can absorb oxygen in the light-emitting device, thereby avoiding the erosion of the electrode layer by oxygen and effectively ensuring the protection of the device. stability and extend device life.

Description

Light emitting device and manufacturing method thereof

technical field

The present application relates to the display field, in particular to a light emitting device and a manufacturing method thereof.

Background technique

Light-emitting devices such as Organic Light Emitting Diode (OLED) and Quantum Dot Light Emitting Diode (QLED) light-emitting devices have wide viewing angles, high contrast, high response speed, high brightness, etc. Advantages, and gradually become the mainstream of the display field.

However, current OLED and QLED display packaging technologies and packaging materials cannot completely avoid the intrusion of oxygen. When oxygen remains or enters the light-emitting device from the outside, the interface between the functional layer such as the electron transport layer and the electrode will be oxidized, the transport property will be changed, and the binding force between the interfaces will be reduced. When the light-emitting device is energized or heated, it will intensify the oxidation process, resulting in rapid aging and failure of the device, and a sharp decrease in device performance. Therefore, it is necessary to propose a scheme to reduce the influence of oxygen on the light-emitting device, improve the photoelectric characteristics of the device, and prolong the lifetime of the device.

Contents of the invention

In view of this, the purpose of the present application is to provide a light-emitting device capable of reducing the influence of oxygen on the light-emitting device and a manufacturing method thereof.

The application provides a light emitting device, which includes:

first electrode layer;

an electrode protection layer, disposed on the first electrode layer, and an oxygen absorbing material is dispersed in the electrode protection layer;

a light-emitting layer disposed on a side of the electrode protection layer away from the first electrode layer; and

The second electrode layer is arranged on the side of the light-emitting layer away from the electrode protection layer.

In one embodiment, the oxygen absorbing material includes one or more of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide and cadmium sulfide.

In one embodiment, the oxygen absorbing material is composed of one or more of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide and cadmium sulfide.

In one embodiment, a hydrogen absorbing material is also dispersed in the electrode protection layer.

In one embodiment, the hydrogen absorbing material includes at least one of C60+Ca and _TiSi2 .

In one embodiment, the hydrogen absorbing material consists of at least one of C60+Ca and _TiSi2 .

In one embodiment, the electrode protection layer includes an organic film, the oxygen absorbing material is dispersed in the organic film, and the material of the organic film includes polyethylene terephthalate, polyimide , polycarbonate, acrylic resin, epoxy resin, polymethyl methacrylate and polystyrene.

In one embodiment, the electrode protection layer includes an organic film and a hydrogen absorbing material, the oxygen absorbing material and the hydrogen absorbing material are dispersed in the organic film, and in the electrode protection layer, the organic film The mass fraction of the material is 50wt% to 75wt%; the mass fraction of the oxygen absorbing material is 12.5wt% to 25wt%; the mass fraction of the hydrogen absorbing material is 12.5wt% to 25wt%.

In one embodiment, a hole eliminating agent is also dispersed in the electrode protection layer.

In one embodiment, the hole eliminator includes one or more of triethanolamine, polyethylene glycol, polyvinyl alcohol, and polyethylene oxide.

In one embodiment, the electrode protection layer includes an organic film and a hydrogen absorbing material, the oxygen absorbing material and the hydrogen absorbing material are dispersed in the organic film, and in the electrode protection layer, the organic film The mass fraction of the material is 50wt% to 65wt%; the mass fraction of the oxygen absorbing material is 12.5wt% to 15wt%; the mass fraction of the hydrogen absorbing material is 12.5wt% to 15wt%; the mass fraction of the triethanolamine The fraction is from 10 wt% to 20 wt%.

In one embodiment, the first electrode layer is a cathode layer, and the light emitting device further includes an electron transport layer, and the electron transport layer is disposed between the electrode protection layer and the light emitting layer.

The present application provides a method for manufacturing a light emitting device, which includes the following steps:

forming a first electrode layer;

forming an electrode protection layer on the first electrode layer;

forming a light emitting layer on a side of the electrode protection layer away from the first electrode layer; and

forming a second electrode layer on the side of the light-emitting layer away from the electrode protection layer to obtain a light-emitting device;

Wherein, the step of forming an electrode protection layer on the first electrode layer comprises:

providing an electrode protection solution comprising an oxygen absorbing material; and

The electrode protection solution is formed on the surface of the first electrode layer, and cured to form a film to obtain an electrode protection layer.

In one embodiment, the manufacturing method of the light emitting device further includes packaging the light emitting device; and

The packaged light emitting device is irradiated with ultraviolet rays.

The present application provides a light emitting device and a manufacturing method thereof. The light emitting device includes a first electrode layer, an electrode protection layer, a light emitting layer and a second electrode layer. The electrode protection layer is disposed on the first electrode layer. An oxygen absorbing material is dispersed in the electrode protection layer. The light emitting layer is arranged on the side of the electrode protection layer away from the first electrode layer. The second electrode layer is arranged on the side of the light emitting layer away from the electrode protection layer. In this application, an electrode protection layer is formed on the side of the first electrode layer. Oxygen absorbing particles are dispersed in the electrode protection layer. The oxygen absorbing particles can absorb oxygen in the light-emitting device, thereby avoiding the erosion of the electrode layer by oxygen and effectively ensuring the protection of the device. stability and prolong device life.

Description of drawings

In order to illustrate the technical solutions in this application more clearly, the drawings that need to be used in the description of the implementation will be briefly introduced below. Obviously, the drawings in the following description are only some implementations of the application. Those skilled in the art can also obtain other drawings based on these drawings without any creative work.

FIG. 1 is a schematic structural diagram of a light emitting device according to a first embodiment of the present application.

FIG. 2 is a schematic structural diagram of the electrode protection layer in FIG. 1 .

FIG. 3 is a schematic structural view of an electrode protection layer in a light emitting device according to a second embodiment of the present application.

Fig. 4 is a schematic structural diagram of a light emitting device according to a third embodiment of the present application.

Fig. 5 is a schematic structural diagram of a light emitting device according to a fourth embodiment of the present application.

Fig. 6 is a flow chart of a method for manufacturing a light emitting device provided in the fifth embodiment of the present application.

FIG. 7 is a flowchart of forming an electrode protection layer on the first electrode layer in FIG. 6 .

Fig. 8 is a flowchart of a method for manufacturing a light emitting device provided in the sixth embodiment of the present application.

Detailed ways

The following will clearly and completely describe the technical solution in the application with reference to the accompanying drawings in the implementation manner of the application. Apparently, the described implementations are only some of the implementations of this application, not all of them. Based on the implementation manners in this application, all other implementation manners obtained by those skilled in the art without creative efforts shall fall within the scope of protection of this application.

The present application provides a light emitting device. For example, the light emitting device may be an OLED light emitting device, or may be a QLED light emitting device.

Due to the unique optical properties of quantum dots, such as continuously adjustable emission wavelength with size and composition, narrow emission spectrum, high fluorescence efficiency, and good stability, QLED has received extensive attention and research in the field of display. Hereinafter, the present application will be described in detail based on QLED.

Please refer to FIG. 1 and FIG. 2 . FIG. 1 is a schematic structural diagram of a light emitting device according to a first embodiment of the present application. FIG. 2 is a schematic structural diagram of the electrode protection layer in FIG. 1 . The light emitting device 100 provided in the first embodiment of the present application includes:

the first electrode layer 10;

The electrode protection layer 20 is disposed on the first electrode layer 10, and an oxygen absorbing material 21 is dispersed in the electrode protection layer 20;

The light emitting layer 30 is disposed on the side of the electrode protection layer 20 away from the first electrode layer 10; and

The second electrode layer 40 is disposed on a side of the light emitting layer 30 away from the electrode protection layer 20 .

In this embodiment, the light emitting device 100 is a bottom emitting device. The first electrode layer 10 may be a cathode layer. The cathode layer can be a metal cathode. The material of the cathode layer may include one of Al, Ca, Ba, Ag or stacked metals thereof.

The electrode protection layer 20 is located between the first electrode layer 10 and the light emitting layer 30 for protecting the first electrode layer 10 . In some embodiments, the electrode protection layer 20 may also be directly disposed on the surface of the first electrode layer 10 , that is, the electrode protection layer 20 is in direct contact with the surface of the first electrode layer 10 . In other embodiments, the electrode protection layer 20 may not be in direct contact with the first electrode layer 10 . Oxygen will remain in the light emitting device 100 due to limitations of packaging materials and processes, or oxygen will intrude into the light emitting device 100 during use. The oxygen absorbing material 21 in the electrode protection layer 20 can absorb oxygen in the light-emitting device, thereby avoiding the corrosion of the electrode layer, especially the first electrode layer 10 by oxygen, effectively ensuring the stability of the device and prolonging the service life of the device.

The oxygen absorbing material 21 may be a photocatalytic material capable of generating electron-hole pairs. Specifically, the oxygen absorbing material 21 may include one or more of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide and cadmium sulfide. The oxygen absorbing material 21 may also include ferric oxide, tin oxide, cobalt oxide, perovskite type composite oxide lanthanum iron trioxide LaFeO ₃ , lanthanum cobalt trioxide LaCoO ₃ and the like. As the oxygen absorbing material 21, one of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide, and cadmium sulfide may be used alone, or multiple types may be used in combination. In one embodiment, the oxygen absorbing material 21 is composed of one or more of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide and cadmium sulfide. The oxygen absorbing material 21 may be semiconductor nanoparticles. When light with energy greater than or equal to the energy gap is irradiated on semiconductor nanoparticles as a photocatalytic material, the electrons in its valence band will be excited to jump to the conduction band, leaving relatively stable holes in the valence band, thus forming electron-hole pairs. Due to the existence of a large number of defects and dangling bonds in photocatalytic nanomaterials, these defects and dangling bonds can trap electrons or holes and prevent the recombination of electrons and holes. These trapped electrons and holes diffuse to the surface of the particle respectively, and the electrons diffused to the surface of the particle are captured by oxygen, thereby adsorbing oxygen. For example, under light, TiO ₂ can effectively generate electron-hole pairs, and then make O ₂ molecules combine with electrons to generate O ^2- , thereby eliminating oxygen in the interface.

In some embodiments, a hydrogen absorbing material 22 is also dispersed in the electrode protection layer 20 . The hydrogen absorbing material 22 may be selected from materials capable of hydrogen absorbing and hydrogen storage functions. Specifically, the hydrogen absorbing material 22 may include at least one of C60+Ca and TiSi ₂ . Both C60+Ca and TiSi ₂ are excellent hydrogen absorbing and hydrogen storage materials. C60+Ca is C60 surface-modified with calcium. Calcium is strongly adsorbed on C60, and can evenly cover the surface of C60 to form C60 doped with alkali metal calcium element on the surface. The surface of C60 doped with alkali metal calcium element can form a strong electric field near its surface to polarize hydrogen molecules, thereby improving the adsorption capacity of hydrogen molecules and effectively adsorbing hydrogen. As the hydrogen absorbing material 22, only one of C60+Ca and TiSi ₂ may be used, or a mixture of C60+Ca and TiSi ₂ may be used. In one embodiment, the hydrogen absorbing material consists of at least one of C60+Ca and _TiSi2 . When the light emitting device 100 is energized and working, water is electrolyzed to generate a small amount of hydrogen gas, which makes the electrode bubbling and uneven, which may cause black spots. All of these will cause the photoelectric characteristics of the light emitting device 100 to decline sharply, resulting in rapid aging and failure of the light emitting device 100 . By dispersing the hydrogen absorbing material 22 in the electrode protection layer 20, the hydrogen absorbing material 22 can absorb the hydrogen gas generated in the light-emitting device 100 due to electrification, prevent the hydrogen gas from making the electrode layer bubbling and uneven, and prevent the generation of black spots. Thereby improving luminous efficiency and prolonging device life. Moreover, the water vapor remaining in the light-emitting device 100 will be electrolyzed at the cathode layer to generate hydrogen gas, and the electrode protection layer 20 is disposed on the cathode layer side, which can quickly absorb hydrogen gas and have a good protective effect on the cathode layer.

The electrode protection layer 20 includes an organic thin film 20a. The oxygen absorbing material 21 and the hydrogen absorbing material 22 are dispersed in the organic thin film 20a. Since the light emitting device 100 is used in a display panel, the organic thin film 20a may be an organic thin film having high light transmittance. On the other hand, the material of the organic thin film 20a can also be selected from materials with good oxygen barrier properties. Specifically, the material of the organic film 20a may include one of polyethylene terephthalate, polyimide, polycarbonate, acrylic resin, epoxy resin, polymethyl methacrylate and polystyrene. . The material of the organic thin film 20a may also include polyetherimide and polyethersulfone. In this embodiment, the material of the organic film 20a is polyethylene terephthalate. Polyethylene terephthalate has high light transmittance and good performance of isolating oxygen. While ensuring the light transmittance of OLED devices, it can also prevent oxygen intrusion.

In order that the organic thin film 20a can form a film smoothly, achieve the effect of the base skeleton, and ensure the oxygen adsorption and hydrogen adsorption capacity of the electrode protective layer 20, in the electrode protective layer 20, the mass fraction of the material of the organic thin film 20a is 50wt% to 75wt%. ; The mass fraction of the oxygen absorbing material 21 is 12.5wt% to 25wt%; the mass fraction of the hydrogen absorbing material 22 is 12.5wt% to 25wt%. In one embodiment, the mass fraction of the material of the organic thin film 20a is 60wt% to 70wt%; the mass fraction of the oxygen absorbing material 21 is 15wt% to 25wt%; the mass fraction of the hydrogen absorbing material 22 is 15wt% to 25wt%.

The material of the light emitting layer 30 may be quantum dot light emitting material. Quantum dot luminescent materials can be selected from Group IV, II-V, II-VI, III-VI, III-V, IV-VI, VI-VI, VIII-VI, I- At least one of III-VI, II-IV-VI, II-IV-V single or composite structure quantum dots. Composite structure quantum dots include core-shell structure quantum dots, and the core materials of core-shell structure quantum dots include CdSe, CdS, CdTe, CdSeTe, CdZnS, PbSe, ZnTe, CdSeS, PbS, PbTe, HgS, HgSe, HgTe, GaN, At least one of GaP, GaAs, InP, InAs, InZnP, InGaP and InGaN; the material constituting the shell of the core-shell quantum dot contains at least one of ZnSe, ZnS and ZnSeS.

The second electrode layer 40 may be an anode layer. The material of the anode layer can be selected from transparent oxide materials such as indium tin oxide and indium zinc oxide.

In this application, an electrode protection layer is formed on the surface of the electrode layer. Oxygen absorbing particles are dispersed in the electrode protection layer. The oxygen absorbing particles can absorb oxygen in the light-emitting device, thereby avoiding the erosion of the electrode layer by oxygen and effectively ensuring the stability of the device. performance and prolong device life. In addition, the hydrogen absorbing material is dispersed in the electrode protection layer, and the hydrogen absorbing material can absorb the hydrogen gas generated in the light-emitting device due to electrification, preventing the hydrogen gas from making the electrode layer bubbling and uneven, and preventing the occurrence of black spots. Thereby improving luminous efficiency and prolonging device life.

Please refer to FIG. 3 , which is a schematic structural diagram of an electrode protection layer in a light emitting device according to a second embodiment of the present application. The structure of the light emitting device 100 provided by the second embodiment of the present application is substantially the same as that of the first embodiment, the only differences are:

A hole eliminating agent 23 is also dispersed in the electrode protection layer 20 . As the hole eliminator 23, an organic substance having a lone pair of electrons can be used. The hole eliminator 23 can combine with holes, thereby eliminating holes generated by the oxygen absorbing material 21 . The hole eliminator 23 may include one or more of triethanolamine, polyethylene glycol, polyvinyl alcohol, and polyethylene oxide. Cavitation eliminator 23 may also include methanol, ethanol, isopropanol, formic acid, ascorbic acid, and ethylenediaminetetraacetic acid. In this embodiment, the hole eliminator 23 is triethanolamine. The nitrogen of triethanolamine has a lone pair of electrons, which can effectively eliminate the holes generated by _TiO2 , so that electrons can better combine with _O2 .

In order that the organic thin film 20a can form a film smoothly, achieve the effect of the base skeleton, and ensure the oxygen adsorption and hydrogen adsorption capacity of the electrode protective layer 20, in the electrode protective layer 20, the mass fraction of the material of the organic thin film 20a is 50wt% to 65wt%; The mass fraction of oxygen absorbing material 21 is 12.5wt% to 15wt%; the mass fraction of hydrogen absorbing material is 12.5wt% to 15wt%; the mass fraction of triethanolamine is 10wt% to 20wt%.

Please refer to FIG. 4 , which is a schematic structural diagram of a light emitting device according to a third embodiment of the present application. The structure of the light emitting device 100 provided by the third embodiment of the present application is substantially the same as that of the first embodiment, except that the light emitting device 100 further includes an electron transport layer 50 , and a hole injection layer 70 and a hole transport layer 60 . The electron transport layer 50 is disposed between the electrode protection layer 20 and the light emitting layer 30 . The material of the electron transport layer 50 is one or more of n-type ZnO, TiO ₂ , SnO, Ta ₂ O ₃ , AlZnO, ZnSnO, InSnO, Alq ₃ , Ca, Ba, CsF, LiF, and CsCO ₃ . The material of the hole transport layer 60 may be one or more of PVK, Poly-TPD, CBP, TCTA and TFB.

The hole transport layer 60 is located between the second electrode layer 40 and the light emitting layer 30 .

The hole injection layer 70 is located between the hole transport layer 60 and the second electrode layer 40 . The material of the hole injection layer 70 may be one or more of PEDOT:PSS, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, molybdenum sulfide, tungsten sulfide, and copper oxide.

In this embodiment, the electrode protection layer 20 is located between the cathode layer and the electron transport layer 50 . Because when oxygen enters into the device, it will affect the contact between the cathode layer and the electron transport layer 50, reducing the binding force between the two. When the electrode protective layer 20 is provided between the cathode layer and the electron transport layer 50 , the binding force between the cathode layer and the electron transport layer 50 can be enhanced. Moreover, the water vapor remaining in the light-emitting device will be electrolyzed at the cathode layer to generate hydrogen gas, and the electrode protection layer 20 is arranged on the side of the cathode layer, which can quickly absorb hydrogen gas and have a good protective effect on the cathode layer.

Please refer to FIG. 5 , which is a schematic structural diagram of a light emitting device according to a fourth embodiment of the present application. The fourth embodiment of the present application provides a light emitting device 100, the structure of which is substantially the same as that of the third embodiment, the only differences are:

The light emitting device 100 is a top emission device. The first electrode layer 10 is an anode layer. The anode layer can be a metal anode. The material of the anode layer may include one of Al, Ca, Mg, Ag or stacked metals thereof. The second electrode layer 40 is a cathode. The material of the cathode can be selected from transparent conductive materials such as indium tin oxide and indium zinc oxide.

Specifically, the light emitting device includes a first electrode layer 10 , an electrode protection layer 20 , a hole injection layer 70 , a hole transport layer 60 , a light emitting layer 30 , an electron transport layer 50 and a second electrode layer 40 stacked in sequence.

Please refer to FIG. 6 , which is a flowchart of a method for manufacturing a light emitting device according to a fifth embodiment of the present application. FIG. 7 is a flowchart of forming an electrode protection layer on the first electrode layer in FIG. 6 . The method for manufacturing a light emitting device according to the fifth embodiment of the present application includes the following steps:

1: forming the first electrode layer;

2: forming an electrode protection layer on the first electrode layer;

3: forming a light-emitting layer on the side of the electrode protection layer away from the first electrode layer; and

4: forming a second electrode layer on the side of the light-emitting layer away from the electrode protection layer to obtain a light-emitting device;

Wherein, step 2 also includes the following steps:

21: dissolving the organic material and the oxygen absorbing material in an organic solvent to form an electrode protection solution; and

22: forming an electrode protection solution on the surface of the first electrode layer, and curing it to form a film to obtain an electrode protection layer.

In step 21, the method of forming the electrode protection solution on the surface of the first electrode layer includes but not limited to spin coating method, dipping and pulling method, printing method, printing method, inkjet method, spray coating method, roll coating method, scraping method, etc. One or more of coating method, casting method, electrodeposition method, slit coating method and strip coating method. The oxygen absorbing material 21 may be a photocatalytic material capable of generating electron-hole pairs. Specifically, the oxygen absorbing material 21 may include one or more of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide and cadmium sulfide. The oxygen absorbing material 21 may also include ferric oxide, tin oxide, cobalt oxide, perovskite type composite oxide lanthanum iron trioxide LaFeO ₃ , lanthanum cobalt trioxide LaCoO ₃ and the like. As the oxygen absorbing material 21, one of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide, and cadmium sulfide may be used alone, or multiple types may be used in combination.

In step 21, a hydrogen absorbing material 22 may also be added to the organic solvent. The hydrogen absorbing material 22 may be selected from materials capable of hydrogen absorbing and hydrogen storage functions. Specifically, the hydrogen absorbing material 22 may include at least one of C60+Ca and TiSi ₂ . Both C60+Ca and TiSi ₂ are excellent hydrogen absorbing and hydrogen storage materials.

The organic solvent consists of phenol and ethanol. The volume fraction of each component in the organic solvent is: phenol, 75%-85%; ethanol, 15%-25%. In other embodiments, the organic solvent may also consist of phenol and chloroform. The volume fraction of each component in the solution is: phenol, 75%-85%; chloroform, 15%-25%.

The organic material, the oxygen absorbing material and the hydrogen absorbing material are uniformly dispersed in the organic solvent, and the total mass of solvent plus solute per milliliter may be 1 mg/ml to 20 mg/ml. That is, the concentrations of the organic material, the oxygen absorbing material, and the hydrogen absorbing material may be 1 mg/ml to 20 mg/ml.

In one embodiment, in order that the organic thin film 20a can form a film smoothly, achieve the effect of the base skeleton, and ensure the oxygen adsorption and hydrogen adsorption capabilities of the electrode protective layer 20, in the electrode protective layer 20, the mass fraction of the material of the organic thin film 20a 50wt% to 75wt%; the mass fraction of the oxygen absorbing material is 12.5wt% to 25wt%; the mass fraction of the hydrogen absorbing material is 12.5wt% to 25wt%.

In another embodiment, step 21 is: mixing organic material, oxygen absorbing material, hydrogen absorbing material and hole eliminating agent to form a solution. The hole eliminator 23 may include one or more of triethanolamine, polyethylene glycol, polyvinyl alcohol, and polyethylene oxide. The hole absorber 23 may also include methanol, ethanol, isopropanol, formic acid, ascorbic acid, and ethylenediaminetetraacetic acid. In order that the organic thin film 20a can form a film smoothly, achieve the effect of the base skeleton, and ensure the oxygen adsorption and hydrogen adsorption capacity of the electrode protective layer, in the electrode protective layer, the mass fraction of the material of the organic thin film 20a is 50wt% to 65wt%; The mass fraction of the material is 12.5wt% to 15wt%, the mass fraction of the hydrogen absorbing material is 12.5wt% to 15wt%, and the mass fraction of the triethanolamine is 10wt% to 20wt%.

It should be noted that the above sequence of steps used in the method is for illustration only, and the steps of the method of the present invention are not limited to the sequence described above, unless otherwise specified.

Please refer to FIG. 8 . FIG. 8 is a flowchart of a method for manufacturing a light emitting device provided in the sixth embodiment of the present application. The manufacturing method of the light emitting device provided in the sixth embodiment of the present application is substantially the same as the manufacturing method of the light emitting device in the fifth embodiment, except that:

The manufacturing method of the light emitting device also includes:

Step 5: packaging the light emitting device; and

Step 6: irradiating ultraviolet rays to the packaged light-emitting device.

In step 6, the ultraviolet irradiation time can be 15 minutes to 30 minutes. By irradiating ultraviolet rays to the packaged light-emitting device, the photocatalytic material can be effectively promoted to generate electrons, thereby eliminating oxygen and improving the oxidation resistance of the device.

Hereinafter, the manufacturing method of the light-emitting device of the present application will be described with reference to specific examples.

Example 1

The manufacturing method of the light-emitting device of Example 1 of the present application includes the following steps:

Forming a transparent anode on the substrate, the material of the transparent anode may be indium tin oxide, and the method of forming the transparent anode may be to deposit indium tin oxide and pattern it;

Spin-coating a hole-injection layer on a transparent anode;

spin-coating a hole transport layer on the hole injection layer;

spin-coating quantum dot luminescent layer on the hole transport layer;

Spin-coat the electron transport layer on the quantum dot light-emitting layer;

Spin-coat the electrode protection layer on the electron transport layer;

Evaporating metal electrodes on the electrode protection layer; and

The light emitting device is packaged.

Among them, the preparation process of the electrode protective layer solution is: blending polyethylene terephthalate, TiO ₂ , C60+Ca according to the mass ratio of 5:1:1 and dissolving them in phenol with a volume ratio of 5:1: The organic solvent of ethanol obtains the electrode protection layer solution. The concentration of the solute in the electrode protection layer solution is 10mg/ml. While stirring on the stirring table, heat while heating, the heating temperature is 60°C, and the heating time is 24h. After fully dissolving, sonicate for 15 minutes, and filter through a 0.22 μm filter head to obtain the electrode protection layer solution. The spin-coating speed of the electrode protective layer solution was 5000 RPM, and the spin-coating time was 30s.

Example 2

The manufacturing method of the light-emitting device of Example 2 of the present application includes the following steps:

Forming a transparent anode on the substrate, the material of the transparent anode may be indium tin oxide, and the method of forming the transparent anode may be to deposit indium tin oxide and pattern it;

Spin-coating a hole-injection layer on a transparent anode;

Spin-coating a hole transport layer on the hole injection layer;

spin-coating quantum dot luminescent layer on the hole transport layer;

Spin-coat the electron transport layer on the quantum dot light-emitting layer;

Spin-coat the electrode protection layer on the electron transport layer;

Evaporating metal electrodes on the electrode protection layer; and

The light emitting device is packaged.

Among them, the preparation process of the electrode protective layer solution is: blending polyethylene terephthalate, TiO ₂ , triethanolamine, and C60+Ca composite materials in a mass ratio of 5:1:1:1 and dissolving them in a volume The organic solvent of phenol:ethanol with a ratio of 5:1 was used to obtain the electrode protection layer solution. The concentration of the solute in the electrode protection layer solution is 10 mg/ml. While stirring on the stirring table, heat while heating, the heating temperature is 60°C, and the heating time is 24h. After fully dissolving, sonicate for 15 minutes, and filter through a 0.22 μm filter head to obtain the electrode protection layer solution. The spin-coating speed of the electrode protective layer solution was 5000 RPM, and the spin-coating time was 30s.

Example 3

The manufacturing method of the light-emitting device of Example 3 of the present application comprises the following steps:

Forming a transparent anode on the substrate, the material of the transparent anode may be indium tin oxide, and the method of forming the transparent anode may be to deposit indium tin oxide and pattern it;

Spin-coating a hole-injection layer on a transparent anode;

spin-coating a hole transport layer on the hole injection layer;

spin-coating quantum dot luminescent layer on the hole transport layer;

Spin-coat the electron transport layer on the quantum dot light-emitting layer;

Spin-coat the electrode protection layer on the electron transport layer;

Evaporate metal electrodes on the electrode protection layer;

Encapsulating the light emitting device; and

The packaged light-emitting device is irradiated with ultraviolet rays for 15 minutes.

Among them, the preparation process of the electrode protective layer solution is: blending polyethylene terephthalate, TiO ₂ , C60+Ca according to the mass ratio of 5:1:1 and dissolving them in phenol with a volume ratio of 5:1: A mixed solvent of ethanol is used to obtain an electrode protective layer solution. The concentration of the solute in the electrode protection layer solution is 10 mg/ml, add a stirring bar on the stirring table at 60° C., heat for 24 hours, the rotation speed is 5000 RPM, and the rotation time is 30 s. After fully dissolved, sonicate for 15 minutes, filter with a 0.22 μm filter head and use it.

comparative example

The manufacturing method of the light-emitting device of the comparative example of the present application includes the following steps:

Forming a transparent anode on the substrate, the material of the transparent anode may be indium tin oxide, and the method of forming the transparent anode may be to deposit indium tin oxide and pattern it;

Spin-coating a hole-injection layer on a transparent anode;

spin-coating a hole transport layer on the hole injection layer;

spin-coating quantum dot luminescent layer on the hole transport layer;

Spin-coat the electron transport layer on the quantum dot light-emitting layer;

Evaporating metal electrodes on the electron transport layer; and

The light emitting device is packaged.

For the above-mentioned embodiments 1 to 3 and comparative examples, measure the total hydrogen and oxygen absorption amount, electroluminescence external quantum efficiency (External Quantum Efficiency, EQE) and the time used for the manual maximum brightness 1000nit to decay to 95% within 8h (expressed as T95@1000nit ), the results are shown in Table 1.

Table 1

It can be seen from Table 1 that the light-emitting devices of comparative examples manufactured according to the prior art have no ability to absorb hydrogen and oxygen, while the light-emitting devices manufactured according to Examples 1 to 3 of the present application can absorb hydrogen and oxygen to a certain extent, Thereby obtaining higher external quantum efficiency and longer service life. Comparing Examples 1 and 2, it can be seen that by adding a hole eliminator to the electrode protective layer, the hydrogen and oxygen absorption capacity, external quantum efficiency, and service life can be further improved. Comparing with Examples 1 to 3, it can be seen that by irradiating ultraviolet light after encapsulation, the hydrogen-oxygen absorption capacity, external quantum efficiency, and service life can be further improved.

The present application provides a light emitting device and a manufacturing method thereof. The light emitting device includes a first electrode layer, an electrode protection layer, a light emitting layer and a second electrode layer. The electrode protection layer is disposed on the first electrode layer. Oxygen absorbing material is dispersed in the electrode protection layer. The light emitting layer is arranged on the side of the electrode protection layer away from the first electrode layer. The second electrode layer is arranged on the side of the light emitting layer away from the electrode protection layer. In this application, an electrode protection layer is formed on the side of the first electrode layer. Oxygen absorbing particles are dispersed in the electrode protection layer. The oxygen absorbing particles can absorb oxygen in the light-emitting device, thereby avoiding the erosion of the electrode layer by oxygen and effectively ensuring the protection of the device. stability and extend device life.

The above provides a detailed introduction to the embodiments of the present application. In this paper, specific examples are used to illustrate the principles and embodiments of the present application. The descriptions of the above embodiments are only used to help understand the present application. At the same time, for those skilled in the art, based on the idea of this application, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be construed as limiting the application.

Claims (14)

1. A light emitting device, comprising:

a first electrode layer;

the electrode protection layer is arranged on the first electrode layer, and oxygen absorption materials are dispersed in the electrode protection layer;

the light-emitting layer is arranged on one side, far away from the first electrode layer, of the electrode protection layer; and

and the second electrode layer is arranged on one side of the light-emitting layer, which is far away from the electrode protection layer.

2. A light emitting device according to claim 1, wherein the oxygen absorbing material comprises one or more of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide, and cadmium sulfide.

3. A light emitting device according to claim 1, wherein the oxygen absorbing material is composed of one or more of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide, and cadmium sulfide.

4. A light emitting device according to claim 1, wherein a hydrogen absorbing material is further dispersed in the electrode protection layer.

5. The light-emitting device according to claim 4, wherein the hydrogen-absorbing material comprises C60+ Ca and TiSi ₂ At least one of (1).

6. The light-emitting device according to claim 4, wherein the hydrogen-absorbing material is composed of C60+ Ca and TiSi ₂ At least one of (a).

7. The light-emitting device according to claim 1 or 4, wherein the electrode protective layer comprises an organic film in which the oxygen absorbing material is dispersed, and a material of the organic film comprises one of polyethylene terephthalate, polyimide, polycarbonate, acryl resin, epoxy resin, polymethyl methacrylate, and polystyrene.

8. The light-emitting device according to claim 1, wherein the electrode protection layer comprises an organic thin film and a hydrogen absorbing material, the oxygen absorbing material and the hydrogen absorbing material being dispersed in the organic thin film, and wherein in the electrode protection layer, a mass fraction of a material of the organic thin film is 50wt% to 75wt%; the mass fraction of the oxygen absorbing material is 12.5wt% to 25wt%; the mass fraction of the hydrogen absorbing material is 12.5wt% to 25wt%.

9. A light-emitting device according to any one of claims 1, 4 and 7, wherein a hole eliminating agent is further dispersed in the electrode protective layer.

10. The light emitting device of claim 9, wherein the hole eliminating agent comprises one or more of triethanolamine, polyvinyl alcohol, polyvinyl oxide.

11. The light-emitting device according to claim 10, wherein the electrode protection layer comprises an organic thin film and a hydrogen absorbing material, the oxygen absorbing material and the hydrogen absorbing material being dispersed in the organic thin film, and wherein in the electrode protection layer, a mass fraction of a material of the organic thin film is 50wt% to 65wt%; the mass fraction of the oxygen absorbing material is 12.5wt% to 15wt%; the mass fraction of the hydrogen absorbing material is 12.5wt% to 15wt%; the triethanolamine accounts for 10-20 wt% of the total weight of the composition.

12. A light emitting device according to claim 1, wherein the first electrode layer is a cathode layer, and further comprising an electron transport layer provided between the electrode protective layer and the light emitting layer.

13. A method of manufacturing a light emitting device, comprising the steps of:

forming a first electrode layer;

forming an electrode protection layer on the first electrode layer;

forming a light-emitting layer on one side of the electrode protection layer away from the first electrode layer; and

forming a second electrode layer on one side of the light-emitting layer, which is far away from the electrode protection layer, so as to obtain a light-emitting device;

wherein the step of forming an electrode protection layer on the first electrode layer comprises:

providing an electrode protection solution comprising an oxygen absorbing material; and

and forming the electrode protection solution on the surface of the first electrode layer, and curing to form a film to obtain the electrode protection layer.

14. The method of manufacturing a light emitting device according to claim 13, further comprising encapsulating the light emitting device; and

and irradiating ultraviolet rays to the packaged light emitting device.

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