CN104009165B - A kind of preparation method of organic electroluminescent device - Google Patents

Abstract

The present invention provides an organic electroluminescent device and its preparation method. A carbon aerogel layer and a zinc oxide layer are sequentially formed between a glass substrate and an anode as light extraction layers. This allows light originally emitted to both sides of the anode to be scattered back to the bottom of the device, avoiding total internal reflection and thus improving the device's light extraction efficiency. The preparation method is simple, easy to control and operate, and the raw materials are readily available.

Description

A kind of preparation method of organic electroluminescent device

technical field

The invention belongs to the field of organic electroluminescence, and in particular relates to a preparation method of an organic electroluminescence device.

Background technique

An organic electroluminescent device (OLED) is an energy conversion device that uses organic materials as light-emitting materials and can convert applied electrical energy into light energy. It has outstanding performances such as ultra-thin, self-luminous, fast response, low power consumption, etc., and has extremely broad application prospects in display, lighting and other fields.

The structure of organic electroluminescent devices is a sandwich structure, with one or more organic thin films sandwiched between the cathode and the conductive anode. In a device with a multi-layer structure, the inside of the two poles mainly includes a light emitting layer, an injection layer and a transport layer. The organic electroluminescent device is a carrier-injection light-emitting device. After the anode and the cathode are applied with an operating voltage, holes are injected from the anode and electrons from the cathode into the organic material layer of the working device respectively. Hole-electron pairs are formed in the luminescent material to emit light, and then the light is emitted from the electrodes.

In traditional light-emitting devices, the glass substrate of indium tin oxide transparent conductive film (ITO) is generally used as the light-emitting surface. Absorption and reflection can finally be emitted into the air, but there is a refractive index difference between the glass and ITO interface, which will cause total reflection of light when it reaches the glass from ITO, resulting in loss of light output, resulting in lower overall light output performance.

Contents of the invention

In order to solve the above problems, the present invention aims to provide an organic electroluminescent device with higher light extraction efficiency. The invention also provides a preparation method of the organic electroluminescence device.

In a first aspect, the present invention provides an organic electroluminescent device, comprising a glass substrate, a light extraction layer, an anode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer and The cathode, the light extraction layer includes a carbon airgel layer and a zinc oxide layer, and the material of the carbon airgel layer includes carbon airgel, poly 3,4-dioxyethylene thiophene and polybenzenesulfonate, so The zinc oxide layer is made of zinc oxide.

Preferably, the glass substrate is optical glass with a refractive index higher than 1.8, and the transmittance of the optical glass to visible light with a wavelength of 400-700 nm is greater than 90%.

Preferably, the grade of glass selected for the glass substrate is N-LAF36, N-LASF31A, N-LASF41 or N-LASF44.

The grade is German Schott grade (SCHOTT), among which, the international glass code of N-LAF36 glass is 800424.443, the international glass code of N-LASF31A glass is 883408.551, the international glass code of N-LASF41 glass is 835431.485, and the international glass code of N-LASF44 glass The international glass code is 804465.444.

A carbon airgel layer and a zinc oxide layer are sequentially stacked on a glass substrate as a light extraction layer.

The material of the carbon airgel layer includes carbon airgel, poly(3,4-dioxyethylenethiophene) and polybenzenesulfonate (PEDOT:PSS).

Carbon airgel has the characteristics of good electrical conductivity, large specific surface area, and wide range of density changes. Its structure is a low-density and stable network structure with high porosity, which is conducive to light scattering.

Preferably, the particle size of the carbon airgel is 10-100 nm.

Preferably, the carbon airgel layer has a thickness of 10-30 μm.

Preferably, the total mass ratio of carbon aerogel to poly-3,4-dioxyethylenethiophene and polybenzenesulfonate is 1-20:100.

Preferably, the mass ratio of poly-3,4-dioxyethylenethiophene and polybenzenesulfonate is 2:1-6:1.

The zinc oxide layer is disposed on the carbon airgel layer.

Since zinc oxide (ZnO) belongs to the nanostructure and has a large crystal size, it has a strong scattering effect on light, so that the light originally emitted to both sides of the anode is scattered back to the bottom of the device, reducing the loss of light, and the refraction of zinc oxide The efficiency is lower than that of the anode, which avoids the total reflection phenomenon that occurs when the light is emitted from the anode to the glass substrate, thereby improving the light extraction efficiency of the device.

Preferably, the particle size of the zinc oxide is 50-200 nm.

Preferably, the thickness of the zinc oxide layer is 20-200 nm.

Preferably, the material of the anode is a transparent conductive film selected from indium tin oxide (ITO), aluminum zinc oxide (AZO) or indium zinc oxide (IZO). More preferably, the material of the anode is ITO.

Preferably, the thickness of the anode is 80-300 nm. More preferably, the thickness of the anode is 120nm.

In the present invention, a carbon airgel layer and a zinc oxide layer are sequentially prepared between the glass substrate and the anode as the light extraction layer, and the light emitted from the anode will first reach the zinc oxide layer, due to the low refractive index of zinc oxide and the strong scattering effect on light , the light originally emitted to both sides of the anode can be scattered back to the bottom of the device, and the total reflection phenomenon is avoided, and the light can effectively pass through the zinc oxide layer and reach the carbon airgel layer. Carbon airgel layer has higher porosity and low refractive index, and the present invention adopts the optical glass that refractive index is higher than 1.8 as substrate, therefore has reduced the total emission of light between carbon airgel layer and glass substrate occurs, thereby improving the light extraction efficiency of the device.

A hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer and a cathode are sequentially arranged on the anode.

Preferably, the material of the hole injection layer is molybdenum trioxide (MoO ₃ ), tungsten trioxide (WO ₃ ) or vanadium pentoxide (V ₂ O ₅ ). More preferably, the material of the hole injection layer is MoO ₃ .

Preferably, the hole injection layer has a thickness of 20-80 nm. More preferably, the thickness of the hole injection layer is 50 nm.

Preferably, the hole transport layer is made of 1,1-bis[4-[N,N'-bis(p-tolyl)amino]phenyl]cyclohexane (TAPC), 4,4',4" - Tris(carbazol-9-yl)triphenylamine (TCTA) or N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4' - Diamine (NPB). More preferably, the material of the hole transport layer is NPB.

Preferably, the hole transport layer has a thickness of 20-60 nm. More preferably, the thickness of the hole transport layer is 40 nm.

Preferably, the material of the light-emitting layer is 4-(dinitrile methyl)-2-butyl-6-(1,1,7,7-tetramethyljuronesidine-9-vinyl)-4H-pyridine Fran (DCJTB), 9,10-bis(β-naphthyl)anthracene (ADN), 4,4'-bis(9-ethyl-3-carbazolevinyl)-1,1'-biphenyl (BCzVBi ) or 8-hydroxyquinoline aluminum (Alq ₃ ). More preferably, the material of the light-emitting layer is BCzVBi.

Preferably, the thickness of the light-emitting layer is 5-40 nm. More preferably, the thickness of the light-emitting layer is 25 nm.

The material of the electron transport layer is an organic molecular material that has high electron mobility and can effectively conduct electrons.

Preferably, the material of the electron transport layer is 4,7-diphenyl-1,10-phenanthroline (Bphen), 1,2,4-triazole derivatives or 1,3,5-tri(1-benzene -1H-benzimidazol-2-yl)benzene (TPBi).

More preferably, the 1,2,4-triazole derivative is 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4 - Triazoles (TAZ). More preferably, the material of the electron transport layer is TPBi.

Preferably, the thickness of the electron transport layer is 40-250 nm. More preferably, the electron transport layer has a thickness of 80 nm.

Preferably, the material of the electron injection layer is cesium carbonate (Cs ₂ CO ₃ ), cesium fluoride (CsF), cesium azide (CsN ₃ ) or lithium fluoride (LiF). More preferably, the material of the electron injection layer is LiF.

Preferably, the electron injection layer has a thickness of 0.5-10 nm. More preferably, the thickness of the electron injection layer is 1 nm.

Preferably, the material of the cathode is silver (Ag), aluminum (Al), platinum (Pt) or gold (Au). More preferably, the material of the cathode is aluminum.

Preferably, the thickness of the cathode is 80-250 nm. More preferably, the thickness of the cathode is 150 nm.

In a second aspect, the present invention provides a method for preparing an organic electroluminescent device, comprising the following steps:

Provides a clean glass substrate;

Prepare a light extraction layer on the glass substrate, and the light extraction layer includes a carbon airgel layer and a zinc oxide layer:

The preparation step of the carbon airgel layer is to mix the carbon airgel into poly-3,4-dioxyethylene thiophene and polybenzenesulfonate aqueous solution according to the mass fraction of 1-20% to obtain a mixed solution, and the The mixed solution is spin-coated on the glass substrate, and then dried;

The preparation step of the zinc oxide layer is to vapor-deposit zinc oxide on the carbon airgel layer by electron beam; the condition of the electron beam vapor deposition is that the energy density is 10-100W/cm ² ;

Then prepare the anode by magnetron sputtering transparent conductive film on the zinc oxide layer, the conditions of the magnetron sputtering are acceleration voltage 300～800V, magnetic field 50～200G, power density 1～40W/cm ² ;

A hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer are prepared sequentially on the anode by thermal resistance vapor deposition, and the thermal resistance vapor deposition condition is a pressure of 5×10 ⁻⁵ to 2×10 ^-3 Pa, speed 0.1~1nm/s;

The cathode is prepared by heat resistance vapor deposition on the electron injection layer, and the heat resistance vapor deposition conditions are a pressure of 5×10 ^-5 to 2×10 ^-3 Pa and a speed of 1 to 10 nm/s.

By cleaning the glass substrate, the organic pollutants on the surface of the glass substrate are removed.

Specifically, the cleaning operation of the glass substrate is as follows: the glass substrate is rinsed with distilled water and ethanol in sequence, and then soaked in isopropanol overnight to remove organic pollutants on the glass surface and obtain a clean glass substrate.

Preferably, the glass substrate is optical glass with a refractive index higher than 1.8, and the transmittance to visible light with a wavelength of 400-700 nm is greater than 90%.

Preferably, the grade of glass selected for the glass substrate is N-LAF36, N-LASF31A, N-LASF41 or N-LASF44.

The grade is German Schott grade (SCHOTT), among which, the international glass code of N-LAF36 glass is 800424.443, the international glass code of N-LASF31A glass is 883408.551, the international glass code of N-LASF41 glass is 835431.485, and the international glass code of N-LASF44 glass The international glass code is 804465.444.

On the glass substrate, the carbon airgel layer and the zinc oxide layer were sequentially stacked as the light extraction layer.

Carbon airgel has the characteristics of good electrical conductivity, large specific surface area, and wide range of density changes. Its structure is a low-density and stable network structure with high porosity, which is conducive to light scattering.

The carbon airgel is added into the aqueous solution of poly 3,4-dioxyethylene thiophene and polybenzenesulfonate to obtain a mixed liquid, the mixed liquid is spin-coated on a glass substrate, and then dried to obtain a carbon airgel layer. Wherein, the mass of the added carbon airgel is 1-20% of the mass of the poly-3,4-dioxyethylene thiophene and polybenzenesulfonate aqueous solution.

Preferably, the aqueous solutions of poly-3,4-dioxyethylenethiophene and polybenzenesulfonate are commercially available common items.

Preferably, the mass ratio of poly-3,4-dioxyethylenethiophene to the polybenzenesulfonate is 2:1-6:1.

Preferably, the mass fraction of poly 3, 4-dioxyethylene thiophene in the aqueous solution of poly 3, 4-dioxyethylene thiophene and polybenzenesulfonate is 1% to 5%.

Preferably, the particle size of the carbon airgel is 10-100 nm.

Preferably, the carbon airgel layer has a thickness of 10-30 μm.

Preferably, the spin coating conditions are a rotation speed of 2000-6000 rpm and a time of 10-60 s.

Preferably, the drying conditions are a temperature of 50-200° C. and a time of 15-40 minutes.

The zinc oxide layer is arranged on the carbon airgel layer by means of electron beam evaporation, and the condition of electron beam evaporation is that the energy density is 10-100 W/cm ² .

Since zinc oxide (ZnO) belongs to the nanostructure and has a large crystal size, it has a strong scattering effect on light, so that the light originally emitted to both sides of the anode is scattered back to the bottom of the device, reducing the loss of light, and the refraction of zinc oxide The efficiency is lower than that of the anode, which avoids the total reflection phenomenon that occurs when the light is emitted from the anode to the glass substrate, thereby improving the light extraction efficiency of the device.

Preferably, the particle size of the zinc oxide is 50-200 nm.

Preferably, the thickness of the zinc oxide layer is 20-200 nm.

Preferably, the condition of the electron beam evaporation is an energy density of 25-70 W/cm ² .

The anode is arranged on the other side of the glass substrate by magnetron sputtering.

Preferably, the material of the anode is a transparent conductive film selected from indium tin oxide (ITO), aluminum zinc oxide (AZO) or indium zinc oxide (IZO). More preferably, the material of the anode is ITO.

Preferably, the thickness of the anode is 80-300 nm. More preferably, the thickness of the anode is 120nm.

Preferably, the conditions of magnetron sputtering are acceleration voltage 350-400V, magnetic field 100-180G, power density 20-35W/cm ² .

In the present invention, a carbon airgel layer and a zinc oxide layer are sequentially prepared between the glass substrate and the anode as the light extraction layer, and the light emitted from the anode will first reach the zinc oxide layer, due to the low refractive index of zinc oxide and the strong scattering effect on light , the light originally emitted to both sides of the anode can be scattered back to the bottom of the device, and the total reflection phenomenon is avoided, and the light can effectively pass through the zinc oxide layer and reach the carbon airgel layer. Carbon airgel layer has higher porosity and low refractive index, and the present invention adopts the optical glass that refractive index is higher than 1.8 as substrate, therefore has reduced the total emission of light between carbon airgel layer and glass substrate occurs, thereby improving the light extraction efficiency of the device.

On the anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer and an electron injection layer are sequentially arranged by means of thermal resistance vapor deposition, and the thermal resistance vapor deposition condition is a pressure of 5×10 ^-5 to 2×10 ^-3 Pa, speed 0.1~1nm/s.

Preferably, the conditions for thermal resistance evaporation of the hole injection layer, hole transport layer, light emitting layer, electron transport layer and electron injection layer are pressure 8×10 ^-5 ~5×10 ^-4 Pa, speed 0.2~0.3nm/ s.

Preferably, the material of the hole injection layer is molybdenum trioxide (MoO ₃ ), tungsten trioxide (WO ₃ ) or vanadium pentoxide (V ₂ O ₅ ). More preferably, the material of the hole injection layer is MoO ₃ .

Preferably, the hole injection layer has a thickness of 20-80 nm. More preferably, the thickness of the hole injection layer is 50 nm.

Preferably, the hole transport layer is made of 1,1-bis[4-[N,N'-bis(p-tolyl)amino]phenyl]cyclohexane (TAPC), 4,4',4" - Tris(carbazol-9-yl)triphenylamine (TCTA) or N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4' - Diamine (NPB). More preferably, the material of the hole transport layer is NPB.

Preferably, the hole transport layer has a thickness of 20-60 nm. More preferably, the thickness of the hole transport layer is 40 nm.

Preferably, the material of the light-emitting layer is 4-(dinitrile methyl)-2-butyl-6-(1,1,7,7-tetramethyljuronesidine-9-vinyl)-4H-pyridine Fran (DCJTB), 9,10-bis(β-naphthyl)anthracene (ADN), 4,4'-bis(9-ethyl-3-carbazolevinyl)-1,1'-biphenyl (BCzVBi ) or 8-hydroxyquinoline aluminum (Alq ₃ ). More preferably, the material of the light-emitting layer is BCzVBi.

Preferably, the thickness of the light-emitting layer is 5-40 nm. More preferably, the thickness of the light-emitting layer is 25 nm.

The material of the electron transport layer is an organic molecular material that has high electron mobility and can effectively conduct electrons.

Preferably, the material of the electron transport layer is 4,7-diphenyl-1,10-phenanthroline (Bphen), 1,2,4-triazole derivatives or 1,3,5-tri(1-benzene -1H-benzimidazol-2-yl)benzene (TPBi).

More preferably, the 1,2,4-triazole derivative is 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4 - Triazoles (TAZ). More preferably, the material of the electron transport layer is TPBi.

Preferably, the thickness of the electron transport layer is 40-250 nm. More preferably, the electron transport layer has a thickness of 80 nm.

Preferably, the material of the electron injection layer is cesium carbonate (Cs ₂ CO ₃ ), cesium fluoride (CsF), cesium azide (CsN ₃ ) or lithium fluoride (LiF). More preferably, the material of the electron injection layer is LiF.

Preferably, the electron injection layer has a thickness of 0.5-10 nm. More preferably, the thickness of the electron injection layer is 1 nm.

The cathode is prepared by thermal resistance vapor deposition on the electron injection layer, and the thermal resistance vapor deposition conditions are pressure 5×10 ^-5 ~ 2×10 ^-3 Pa, speed 1 ~ 10nm/s.

Preferably, the conditions for the thermal resistance vapor deposition of the cathode are a pressure of 5×10 ⁻⁴ Pa and a speed of 2˜5 nm/s.

Preferably, the material of the cathode is silver (Ag), aluminum (Al), platinum (Pt) or gold (Au). More preferably, the material of the cathode is aluminum.

Preferably, the thickness of the cathode is 80-250 nm. More preferably, the thickness of the cathode is 150 nm.

The present invention has following beneficial effects:

(1) In the present invention, a carbon airgel layer and a zinc oxide layer are sequentially prepared between the glass substrate and the anode as the light extraction layer. The light emitted from the anode will first reach the zinc oxide layer. The strong scattering effect can make the light originally emitted to both sides of the anode return to the bottom of the device through scattering, and avoid the total reflection phenomenon, and the light can effectively pass through the zinc oxide layer and reach the carbon airgel layer.

(2) carbon airgel layer has higher porosity and low refractive index, and the present invention adopts the optical glass that refractive index is higher than 1.8 as substrate, therefore has reduced light between carbon airgel layer and glass substrate The occurrence of full emission improves the light extraction efficiency of the device.

(3) The preparation method of the present invention is simple, easy to control and operate, and the raw materials are easy to obtain.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Figure 1 is a structural diagram of an organic electroluminescent device provided in Example 1 of the present invention;

Fig. 2 is a graph showing the relationship between the brightness and lumen efficiency of the organic electroluminescent device provided by Example 1 of the present invention and the existing organic electroluminescent device.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Example 1

A method for preparing an organic electroluminescent device, comprising the following steps:

(1) After rinsing the N-LASF44 glass with distilled water and ethanol, soak it in isopropanol for one night to obtain a clean glass substrate;

(2) In the high-vacuum coating system (Shenyang Scientific Instrument Development Center Co., Ltd.), the carbon airgel with a particle size of 20nm is added to PEDOT:PSS aqueous solution according to the mass fraction of 15%, to obtain a mixed solution, and the mixture is mixed at a speed of 3000rpm. The mixed solution was spin-coated for 20 s and set on a clean glass substrate, and then dried at 100 °C for 30 min to obtain a carbon airgel layer with a thickness of 25 μm, wherein the mass fraction of PEDOT in PEDOT:PSS aqueous solution was 3.5%, and PEDOT and The mass ratio of PSS is 3:1;

ZnO with a particle size of 80nm is placed on the carbon airgel layer by electron beam evaporation to obtain a zinc oxide layer with a thickness of 100nm, wherein the condition of electron beam evaporation is energy density 25W/cm ² ;

(3) Prepare anode by magnetron sputtering ITO, thickness is 120nm, condition is accelerating voltage 400V, magnetic field 100G, power density 20W/cm ² ;

(4) Then, under the condition of a pressure of 5×10 ^-4 Pa, the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer are sequentially thermally deposited on the anode at a vapor deposition rate of 0.2nm/s 1. Electron injection layer, the cathode is prepared by thermal resistance evaporation on the surface of the electron injection layer at an evaporation rate of 5nm/s, and an organic electroluminescent device is obtained.

Specifically, in this embodiment, the material of the hole injection layer is MoO ₃ with a thickness of 50 nm; the material of the hole transport layer is NPB with a thickness of 40 nm; the material of the light emitting layer is BCzVBi with a thickness of 25 nm; the electron transport layer The material of the material is TPBi with a thickness of 80nm; the material of the electron injection layer is LiF with a thickness of 1nm; the material of the cathode is aluminum with a thickness of 150nm.

After the above steps are completed, an organic electroluminescence device is obtained, and the structure is specifically expressed as: N-LASF44 glass/carbon aerogel/PEDOT:PSS/ZnO/ITO/MoO ₃ /NPB/BCzVBi/TPBi/LiF/Al.

Utilize the Keithley2400 of Keithley Company of the United States to test the electrical properties, the colorimeter (Konica Minolta Company of Japan, model: CS-100A) to test the brightness and chromaticity, and the fiber optic spectrometer (Ocean Optics Company of the United States, model: USB4000) to test the electrical properties. Luminescence Spectrum.

FIG. 1 is a schematic structural view of the organic electroluminescence device of this embodiment. As shown in Figure 1, the structure of the organic electroluminescent device includes a glass substrate 10, a light extraction layer 20, an anode 30, a hole injection layer 40, a hole transport layer 50, a light emitting layer 60, and an electron transport layer 70 stacked in sequence. , the electron injection layer 80 and the cathode 90, wherein the light extraction layer includes a carbon airgel layer 201 and a zinc oxide layer 202.

Fig. 2 is a graph showing the relationship between the brightness and lumen efficiency of the organic electroluminescent device of this embodiment and the existing light emitting device. Wherein, Curve 1 is a relationship diagram between the brightness and current efficiency of the organic electroluminescent device of this embodiment; Curve 2 is a relationship diagram between the brightness and current efficiency of an existing light-emitting device.

It can be seen from Fig. 2 that, under different luminances, the lumen efficiency of the organic electroluminescent device of this embodiment is larger than that of the existing light-emitting device, and the maximum lumen efficiency is 6.21m/W, while the lumen efficiency of the existing light-emitting device It is only 4.4lm/W, and the lumen efficiency of existing light-emitting devices decreases rapidly with the increase of brightness, which shows that the light extraction composite layer is composed of carbon airgel layer and zinc oxide layer, which can make light output to high refraction High-efficiency substrate, thus extracting into the air, and zinc oxide has a strong scattering of light, the light emitted from the side can be scattered back to the bottom direction, this composite layer first through scattering, and then by reducing the probability of total reflection to improve Light extraction efficiency, thereby improving luminous efficiency.

Example 2

A method for preparing an organic electroluminescent device, comprising the following steps:

(1) Rinse the N-LAF36 glass with distilled water and ethanol, and soak it in isopropanol for one night to obtain a clean glass substrate;

(2) In the high-vacuum coating system (Shenyang Scientific Instrument Development Center Co., Ltd.), the carbon airgel with a particle size of 10nm is added to PEDOT:PSS aqueous solution according to the mass fraction of 20%, to obtain a mixed solution, which is mixed at a speed of 2000rpm The mixed solution was spin-coated for 10 s and set on a clean glass substrate, and then dried at 50 °C for 40 min to obtain a carbon airgel layer with a thickness of 30 μm, wherein the mass fraction of PEDOT in the PEDOT:PSS aqueous solution was 1%, and PEDOT and The mass ratio of PSS is 2:1;

ZnO with a particle size of 200nm is placed on the carbon airgel layer by electron beam evaporation to obtain a zinc oxide layer with a thickness of 20nm, wherein the condition of electron beam evaporation is energy density 100W/cm ² ;

(3) prepare anode by magnetron sputtering IZO, thickness is 80nm, condition is accelerating voltage 800V, magnetic field 200G, power density 1W/cm ² ;

(4) Then, under the condition of a pressure of 2×10 ^-3 Pa, the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer are sequentially thermally deposited on the anode at a vapor deposition rate of 0.1nm/s 1. Electron injection layer, the cathode is prepared by thermal resistance evaporation on the surface of the electron injection layer at an evaporation rate of 10nm/s, and an organic electroluminescent device is obtained.

Specifically, in this embodiment, the material of the hole injection layer is WO ₃ with a thickness of 40 nm; the material of the hole transport layer is TAPC with a thickness of 45 nm; the material of the light emitting layer is DCJTB with a thickness of 5 nm; the electron transport layer The material of the material is TAZ, the thickness is 65nm; the material of the electron injection layer is Cs ₂ CO ₃ , the thickness is 10nm; the material of the cathode is Pt, the thickness is 80nm.

After the above steps are completed, an organic electroluminescent device is obtained, and the structure is specifically expressed as: N-LAF36 glass/carbon aerogel/PEDOT:PSS/ZnO/IZO/WO ₃ /TAPC/DCJTB/TAZ/Cs ₂ CO ₃ /Pt.

Example 3

A method for preparing an organic electroluminescent device, comprising the following steps:

(1) After rinsing the N-LASF31A glass with distilled water and ethanol, soak it in isopropanol for one night to obtain a clean glass substrate;

(2) In the high-vacuum coating system (Shenyang Scientific Instrument Development Center Co., Ltd.), the carbon aerogel with a particle size of 100nm is added to PEDOT:PSS aqueous solution according to the mass fraction of 1%, to obtain a mixed solution, which is mixed at a speed of 6000rpm. The mixed solution was spin-coated for 60 s on a clean glass substrate, and then dried at 200 °C for 15 min to obtain a carbon airgel layer with a thickness of 10 μm, wherein the mass fraction of PEDOT in the PEDOT:PSS aqueous solution was 5%, and PEDOT and The mass ratio of PSS is 6:1;

ZnO with a particle size of 50nm is placed on the carbon airgel layer by electron beam evaporation to obtain a zinc oxide layer with a thickness of 200nm, wherein the condition of electron beam evaporation is energy density 10W/cm ² ;

(3) prepare anode by magnetron sputtering AZO, thickness is 300nm, condition is accelerating voltage 300V, magnetic field 50G, power density 40W/cm ² ;

(4) Then, under the condition of a pressure of 5×10 ^-5 Pa, the hole injection layer, hole transport layer, light emitting layer, electron transport layer, For the electron injection layer, a cathode is prepared by thermal resistance evaporation on the surface of the electron injection layer at an evaporation rate of 1 nm/s to obtain an organic electroluminescent device.

Specifically, in this embodiment, the material of the hole injection layer is V ₂ O ₅ with a thickness of 20nm; the material of the hole transport layer is NPB with a thickness of 60nm; the material of the light emitting layer is ADN with a thickness of 10nm; The material of the transport layer is Bphen with a thickness of 250nm; the material of the electron injection layer is CsF with a thickness of 0.5nm. The material of the cathode is Au, and the thickness is 100 nm.

After the above steps are completed, an organic electroluminescent device is obtained, and the structure is specifically expressed as: N-LASF31A glass/carbon aerogel/PEDOT:PSS/ZnO/AZO/V ₂ O ₅ /NPB/ADN/Bphen/CsF/ Au.

Example 4

A method for preparing an organic electroluminescent device, comprising the following steps:

(1) After rinsing the N-LASF41 glass with distilled water and ethanol, soak it in isopropanol for one night to obtain a clean glass substrate;

(2) In the high-vacuum coating system (Shenyang Scientific Instrument Development Center Co., Ltd.), the carbon airgel with a particle size of 50nm is added to PEDOT: PSS aqueous solution according to the mass fraction of 10%, to obtain a mixed solution, which is mixed at a speed of 4000rpm. The mixed solution was spin-coated for 15 s and set on a clean glass substrate, and then dried at 100 °C for 20 min to obtain a carbon airgel layer with a thickness of 20 μm, wherein the mass fraction of PEDOT in PEDOT:PSS aqueous solution was 2.5%, and PEDOT and The mass ratio of PSS is 3:1;

ZnO with a particle size of 150nm is placed on the carbon airgel layer by electron beam evaporation to obtain a zinc oxide layer with a thickness of 150nm, wherein the condition of electron beam evaporation is energy density 10W/cm ² ;

(3) Prepare anode by magnetron sputtering ITO, thickness is 180nm, condition is acceleration voltage 350V, magnetic field 180G, power density 35W/cm ² ;

(4) Then, under the condition of a pressure of 8×10 ^-5 Pa, the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer are sequentially thermally deposited on the anode at a deposition rate of 0.3 nm/s. 1. Electron injection layer, the cathode is prepared by thermal resistance evaporation on the surface of the electron injection layer at an evaporation rate of 2nm/s, and an organic electroluminescent device is obtained.

Specifically, in this embodiment, the material of the hole injection layer is WO ₃ with a thickness of 80 nm; the material of the hole transport layer is TCTA with a thickness of 20 nm; the material of the light emitting layer is Alq ₃ with a thickness of 40 nm; The material of the layer is TPBi with a thickness of 40nm; the material of the electron injection layer is CsN ₃ with a thickness of 3nm; the material of the cathode is Ag with a thickness of 250nm.

After the above steps are completed, an organic electroluminescence device is obtained, and the structure is specifically expressed as: N-LASF41 glass/carbon aerogel/PEDOT:PSS/ZnO/ITO/WO ₃ /TCTA/Alq ₃ /TPBi/CsN ₃ / Ag.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (4)

1. the preparation method of an organic electroluminescence device, it is characterised in that, comprise the following steps:

Cleaning substrate of glass is provided;

Preparing light removing layer on the glass substrate, described smooth removing layer comprises charcoal-aero gel layer and zinc oxide film:

The preparation process of described charcoal-aero gel layer, for mix in poly-3,4-bis-oxygen vinylthiophene and the polyphenyl sulfonate aqueous solution according to massfraction 1��20% by charcoal-aero gel, obtains mixed solution, is spin-coated in described substrate of glass by described mixed solution, then dries;

The preparation process of described zinc oxide film be by zinc oxide by electron beam evaporation plating on described charcoal-aero gel layer; The condition of described electron beam evaporation plating is energy density 10��100W/cm²;

On described zinc oxide film, magnetron sputtering transparent conductive film prepares anode again, and the condition of described magnetron sputtering is acceleration voltage 300��800V, magnetic field 50��200G, power density 1��40W/cm²;

On described anode, thermal resistance steaming is coated with standby hole injection layer, hole transmission layer, luminescent layer, electron transfer layer and electron injecting layer successively, and it is pressure 5 �� 10 that described thermal resistance steams plating condition^-5��2 �� 10^-3Pa, speed 0.1��1nm/s;

On described electron injecting layer, thermal resistance is steamed and is coated with standby negative electrode, and it is pressure 5 �� 10 that described thermal resistance steams plating condition^-5��2 �� 10^-3Pa, speed 1��10nm/s.

2. the preparation method of organic electroluminescence device as claimed in claim 1, it is characterized in that, described poly-3,4-bis-oxygen vinylthiophene and the polyphenyl sulfonate aqueous solution gather 3, the massfraction of 4-bis-oxygen vinylthiophene is 1%��5%, the mass ratio of described poly-3,4-bis-oxygen vinylthiophene and described polyphenyl sulfonate is 2: 1��6: 1.

3. the preparation method of organic electroluminescence device as claimed in claim 1, it is characterised in that, the particle diameter of described charcoal-aero gel is 10��100nm, and the particle diameter of described zinc oxide is 50��200nm.

4. the preparation method of organic electroluminescence device as claimed in claim 1, it is characterised in that, described substrate of glass be specific refractory power higher than 1.8 opticglass, and be that the transmitance of the visible ray of 400��700nm is greater than 90% to wavelength.