CN113991029B - A blue light organic electroluminescent device and a display device containing the same - Google Patents
A blue light organic electroluminescent device and a display device containing the same Download PDFInfo
- Publication number
- CN113991029B CN113991029B CN202111225846.1A CN202111225846A CN113991029B CN 113991029 B CN113991029 B CN 113991029B CN 202111225846 A CN202111225846 A CN 202111225846A CN 113991029 B CN113991029 B CN 113991029B
- Authority
- CN
- China
- Prior art keywords
- layer
- organic electroluminescent
- electroluminescent device
- host
- group
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K50/00—Organic light-emitting devices
- H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
- H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/615—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/615—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
- H10K85/624—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene containing six or more rings
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/615—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
- H10K85/626—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene containing more than one polycyclic condensed aromatic rings, e.g. bis-anthracene
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/631—Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/631—Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
- H10K85/633—Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine comprising polycyclic condensed aromatic hydrocarbons as substituents on the nitrogen atom
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/631—Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
- H10K85/636—Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine comprising heteroaromatic hydrocarbons as substituents on the nitrogen atom
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/649—Aromatic compounds comprising a hetero atom
- H10K85/654—Aromatic compounds comprising a hetero atom comprising only nitrogen as heteroatom
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/649—Aromatic compounds comprising a hetero atom
- H10K85/657—Polycyclic condensed heteroaromatic hydrocarbons
- H10K85/6574—Polycyclic condensed heteroaromatic hydrocarbons comprising only oxygen in the heteroaromatic polycondensed ring system, e.g. cumarine dyes
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K2101/00—Properties of the organic materials covered by group H10K85/00
- H10K2101/40—Interrelation of parameters between multiple constituent active layers or sublayers, e.g. HOMO values in adjacent layers
Landscapes
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Optics & Photonics (AREA)
- Electroluminescent Light Sources (AREA)
Abstract
本发明公开一种蓝光有机电致发光器件及包含其的显示装置。该蓝光有机电致发光器件中，包括依次设置的空穴传输层、电子阻挡层、发光层、空穴阻挡层和电子传输层，所述发光层中，至少包括第一主体和第二主体；其中，所述第一主体和第二主体互为蒽的同系物或蒽的同分异构体。本发明可以至少部分地解决现有技术中OLED蓝光器件存在的发光效率低、寿命短以及成品率低等问题。
The present invention discloses a blue light organic electroluminescent device and a display device comprising the same. The blue light organic electroluminescent device comprises a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer and an electron transport layer arranged in sequence, wherein the light emitting layer comprises at least a first host and a second host; wherein the first host and the second host are homologues of anthracene or isomers of anthracene. The present invention can at least partially solve the problems of low luminous efficiency, short life and low yield of OLED blue light devices in the prior art.
Description
Technical Field
The invention relates to the technical field of display. And more particularly, to a blue organic electroluminescent device and a display apparatus including the same.
Background
Among the devices of the OLED in mass production today, the red and green devices are phosphorescent devices, and the light emitting bodies are both double-body materials. The blue phosphorescence material is delayed in technological process, so that the blue light device produced in mass production is a fluorescent device, and the blue light main body material is a single main body material. By photoexcitation or photoexcitation, 25% of singlet excitons and 75% of triplet excitons can be formed. Since the energy level difference deltaest between S1 and T1 of the anthracene host is large, only 25% of singlet excitons can be utilized, and the low exciton utilization results in low device efficiency, which is a large difference from the phosphorescent device efficiency.
In addition, the blue phosphorescent material produced in mass production also has the phenomenon of crucible hole blocking, and the yield is further reduced.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a blue light organic electroluminescent device and a display device comprising the blue light organic electroluminescent device, which can at least partially solve the problems of low luminous efficiency, short service life, low yield and the like of an OLED blue light device in the prior art.
In a first aspect, the invention provides a blue light organic electroluminescent device, which comprises a hole transport layer, an electron blocking layer, a luminescent layer, a hole blocking layer and an electron transport layer which are sequentially arranged, wherein the luminescent layer at least comprises a first main body and a second main body, and the first main body and the second main body are homologs of anthracene or isomers of anthracene.
Optionally, the photoluminescence spectrum wavelength of the first body and the second body is between 380nm and 470nm, and the absolute value of the photoluminescence spectrum wavelength difference of the first body and the second body is below 10 nm.
Optionally, the mass ratio of the first main body to the second main body is 1:99-99:1.
Optionally, the homolog of anthracene or isomer of anthracene is selected from one of the compounds shown in the following structural formulas:
Optionally, the spirobifluorene derivative is included in at least three of the hole transport layer, the electron blocking layer, the hole blocking layer, and the electron transport layer.
Alternatively, when the spirobifluorene derivative is contained in the hole transporting layer, the difference in energy level of the hole transporting layer from the adjacent layer is +.HOMO +.ltoreq.0.3 eV, and/or
When the spirobifluorene derivative is contained in the electron transport layer, the energy level difference between the electron transport layer and the adjacent layer is equal to or less than 0.3eV.
Optionally, the spirobifluorene derivative has a glass transition temperature of greater than 120 ℃.
Alternatively, each spirobifluorene derivative in each layer is independently selected from one of the compounds represented by the following structural formula I:
Wherein:
r 1、R2、R3 and R 4 are each independently selected from aryl or heteroaryl, and adjacent R 1、R2、R3 and R 4 may be bonded to form a ring;
a. b, c and d are each independently selected from integers from 0 to 4.
Optionally, the spirobifluorene derivative shown in the structural formula I for forming the hole transport layer comprises an electron donating group, wherein the electron donating group is selected from one or more of substituted or unsubstituted arylamine groups, substituted or unsubstituted carbazole groups and substituted or unsubstituted fluorenyl groups.
Optionally, the spirobifluorene derivative shown in the structural formula I for forming the electron transport layer comprises an electron-withdrawing group, wherein the electron-withdrawing group is selected from one or more of substituted or unsubstituted azine group, substituted or unsubstituted phenanthroline group, substituted or unsubstituted phosphino group and substituted or unsubstituted cyano group.
In a second aspect, the present invention provides a display device comprising a blue organic electroluminescent device according to any one of the above.
The beneficial effects of the invention are as follows:
In the blue light organic electroluminescent device provided by the invention, the luminescent layer at least comprises a first main body and a second main body, and the first main body and the second main body are homologs of anthracene or isomers of anthracene. The structure of the homolog of anthracene or the isomer of anthracene has similarity, so that an exciplex is not formed between two molecules to cause spectral red shift, the crystallization phenomenon of the material can be well improved on the basis of keeping the original property of the material, the problem of hole blocking of a crucible of a mass production material is solved, meanwhile, carriers can be directly obtained from adjacent functional layers through the homolog of the anthracene or the isomer of the anthracene with similar structure, energy transfer is not needed, carrier traps are not formed due to the change of concentration proportion, and therefore, the phenomenon of non-luminescence of a device is avoided, and in addition, a good amorphous film is formed, so that the performance of the device is enhanced, and the service life of the device is prolonged. In some preferred examples, the blue-light organic electroluminescent device provided by the invention comprises spirobifluorene derivatives in at least three layer structures adjacent to the luminescent layer, so as to further improve the problems of crystallinity, luminous efficiency and the like of the material.
Drawings
The following describes the embodiments of the present invention in further detail with reference to the drawings.
FIG. 1 shows spectra of the isomer BH-4 single component of anthracene and the isomer system in the examples of the present invention.
Fig. 2 shows a schematic diagram of the combination of HTL layer, EBL layer, HBL layer and ETL layer in an organic electroluminescent device according to an embodiment of the present invention.
Fig. 3 shows a schematic diagram of the combination of HTL layer, EBL layer, HBL layer and ETL layer in yet another organic electroluminescent device according to an embodiment of the present invention.
Fig. 4 shows a schematic diagram of the combination of HTL layer, EBL layer, HBL layer and ETL layer in yet another organic electroluminescent device according to an embodiment of the present invention.
Fig. 5 shows a schematic diagram of the combination of HTL layer, EBL layer, HBL layer and ETL layer in yet another organic electroluminescent device according to an embodiment of the present invention.
Fig. 6 shows a schematic diagram of the combination of HTL layer, EBL layer, HBL layer and ETL layer in yet another organic electroluminescent device according to an embodiment of the present invention.
Detailed Description
In order to more clearly illustrate the present invention, the present invention will be further described with reference to preferred embodiments and the accompanying drawings. Like parts in the drawings are denoted by the same reference numerals. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and that this invention is not limited to the details given herein.
Aiming at the problems that the existing OLED blue light device is low in efficiency, short in service life, easy in crucible hole blocking and the like, the embodiment of the invention provides a blue light organic electroluminescent device and a display device comprising the blue light organic electroluminescent device.
The embodiment of the invention provides a blue light organic electroluminescent device, which comprises a hole transmission layer, an electron blocking layer, a luminescent layer, a hole blocking layer and an electron transmission layer which are sequentially arranged, wherein the luminescent layer at least comprises a first main body and a second main body, and the first main body and the second main body are homologs of anthracene or isomers of anthracene.
In some embodiments, the photoluminescence spectrum wavelength of the first and second bodies is between 380nm and 470nm, and the absolute value of the photoluminescence spectrum wavelength difference of the first and second bodies is below 10 nm. Under such conditions it is ensured that each of the first body and the second body has similar optical properties.
In some embodiments, the mass ratio of the first body to the second body is 1:99-99:1.
The research shows that (1) the crucible hole blocking phenomenon of mass production materials is mainly caused by the crystallization phenomenon of the materials. The structure of the homolog of anthracene or the isomer of anthracene has similarity, wherein the anthracene unit has a larger plane structure, and the structure leads the anthracene material to tend to be planar, so that pi-pi stacking is easy to form between molecules, the material is piled up, crystallization is further initiated, and thus the pore blocking phenomenon is caused in the process of mass production. The material system formed by matching the homologues or the isomers has similar chemical properties, and an exciplex is not formed between the two molecules to lead to spectrum red shift, so that the phenomenon of material crystallization can be well improved on the basis of keeping the original properties of the material, and the problem of crucible hole blockage of the mass production material is solved. (2) The method has the advantages that (1) the homolog of the anthracene or the isomer of the anthracene can directly obtain carriers from adjacent functional layers without energy transfer, so that the phenomenon that a carrier trap is formed due to the change of concentration proportion and a device does not emit light is avoided, and (3) the homolog of the anthracene or the isomer of the anthracene can form a good amorphous film, thereby enhancing the performance of the device and being beneficial to prolonging the service life of the device.
In some embodiments, the homolog of anthracene or isomer of anthracene includes, but is not limited to, one selected from the group consisting of compounds represented by the following structural formulas:
in some preferred embodiments, the first body is The second main body isOr the first body isThe second main body isOr the first body isThe second main body isOr the first body isThe second main body isOr the first body isThe second main body is
It is understood that the light-emitting layer of the blue organic electroluminescent device further comprises a blue light doping material. The blue light doping material is selected without other special requirements, and the blue light doping material is conventionally used in the field.
In some embodiments, the spirobifluorene derivative is included in at least three of the hole transport layer, the electron blocking layer, the hole blocking layer, and the electron transport layer.
Specifically, the materials in the hole transport layer, the electron blocking layer, the hole blocking layer and the electron transport layer all comprise spirobifluorene derivatives, or
The electron blocking layer, the hole blocking layer and the electron transport layer all comprise spirobifluorene derivatives, or
The materials in the hole transport layer, the hole blocking layer and the electron transport layer all comprise spirobifluorene derivatives, or
The hole transport layer, the electron blocking layer and the electron transport layer each comprise a spirobifluorene derivative, or
The materials in the hole transport layer, the electron blocking layer and the hole blocking layer all comprise spirobifluorene derivatives.
Singlet excitons are generated by collision and fusion (fusion) of two triplet excitons, thereby enhancing fluorescence emission. This phenomenon of generating singlet excitons by collision and fusion of two triplet excitons is hereinafter abbreviated as TTA (triplet-triplet annihilation), and more singlet excitons are generated by effectively utilizing triplet excitons in such a manner, thereby improving the efficiency of the device. This requires a higher T1 for the functional layer adjacent to the light emitting layer to confine the exciton recombination region in the light emitting layer, and a better stability for the molecules on both sides of the light emitting layer to ensure that the material is not degraded and thus the device lifetime is not degraded in the event of a number of triplet excitons continually impinging.
In the technical scheme, the spirobifluorene group in the spirobifluorene derivative has good carrier transmission capability, can play a role in regulating and controlling holes when being connected with the hole transmission group, and has the capability of regulating and controlling electrons when being connected with the electron transmission group. When each EL functional layer contains more spirobifluorene structures, the function of regulating and controlling carriers can be well achieved, and the function of optimizing an EL device can be achieved. (2) Because different functional layers contain the same main structure (spirobifluorene), the energy level difference of holes or electrons between different organic layers can be reduced, so that electron/hole transmission is smoother, thereby improving the luminous efficiency and reducing the starting voltage. (3) The spirobifluorene has a higher T1 segment, and the spirobifluorene segment is introduced into the molecule, so that the T1 of the whole material can be improved. The spirobifluorene structure is introduced into the functional layers at two sides of the light-emitting layer, the functional layers at two sides have higher T1, excitons can be well limited in the light-emitting layer, TTA effect is greatly improved, and then efficiency of the device is improved. (4) The spirobifluorene structure has high stability and is resistant to the attack of exciton polarons, and the spirobifluorene structure is introduced into the molecule, so that the stability of the material can be improved, and the decay of the service life of the device caused by the cracking of the material is avoided. (5) The spirobifluorene structure, two fluorenes are orthogonal three-dimensional space structures, and the rigid three-dimensional structure can avoid pi-pi accumulation among molecules, so that the accumulation of materials is effectively prevented, the crystallization (good space configuration) of the materials can be inhibited to a certain extent, and the luminous performance is improved.
In some embodiments, when the spirobifluorene derivative is included in the hole transporting layer, the difference in energy level between the hole transporting layer and the adjacent layer is +.HOMO +.0.3 eV, for example, +.LUMO (HBL) -LUMO (ETL) +.0.3 eV, and |LUMO (HBL) -LUMO (Host) +.0.3 eV, at which time small energy level gap is beneficial for electron transport, and/or
When the spirobifluorene derivative is contained in the electron transport layer, the energy level difference between the electron transport layer and the adjacent layer is +.LUMO +.0.3 eV, for example, |HOMO (HTL) -HOMO (EBL) |+.0.31 eV, and |HOMO (Host) -HOMO (EBL) |+.0.3 eV, at this time, the problem of slow hole transport due to energy level barrier can be eliminated, and hole transport can be accelerated to some extent.
It will be appreciated by those skilled in the art that LiQ may be contained in the electron transport layer, and the amount of LiQ added in the electron transport layer may be added in conventional amounts. For example, when the spirobifluorene derivative and LiQ are contained in the electron transport layer at the same time, the mass ratio of the spirobifluorene derivative to the LiQ includes, but is not limited to, 1:1, and the like.
In some embodiments, the spirobifluorene derivative has a glass transition temperature greater than 120 ℃. The stability of the material can be better ensured under the condition.
In some preferred embodiments, in the blue-light organic electroluminescent device, each spirobifluorene derivative in each layer is independently selected from one of the compounds represented by the following structural formula I:
Wherein:
r 1、R2、R3 and R 4 are each independently selected from aryl or heteroaryl, and adjacent R 1、R2、R3 and R 4 may be bonded to form a ring;
a. b, c and d are each independently selected from integers from 0 to 4.
In some embodiments, the spirobifluorene derivative shown in the structural formula I for forming the hole transport layer comprises an electron donating group, wherein the electron donating group is selected from one or more of arylamine, carbazolyl and fluorenyl, and/or
The spirobifluorene derivative shown in the structural formula I for forming the electron transport layer comprises an electron withdrawing group, wherein the electron withdrawing group is one or more selected from azine group, phenanthroline group, phosphine oxide group and cyano group.
In some embodiments, the spirobifluorene derivative is selected from one of the following compounds:
in the structure of the spirobifluorene derivative, two fluorenes are in orthogonal three-dimensional space structures, and the rigid three-dimensional structure can avoid pi-pi accumulation among molecules, so that the accumulation of materials is effectively prevented, the crystallization (good space configuration) of the materials can be restrained to a certain extent, and the luminous performance is improved.
In addition, the spirobifluorene derivative structure is a segment with a higher triplet state energy level, and materials formed by the spirobifluorene structure are adopted at two sides of the light-emitting layer, so that the materials have a high triplet state energy level, exciton diffusion of the light-emitting layer can be effectively blocked, and the recombination and the use efficiency of carriers are improved.
When both hole transmission layers/electron blocking layers on two sides of the light-emitting layer contain spirobifluorene structures, the same fragments are contained, so that the HOMO energy level difference between adjacent organic layers can be reduced, the transmission of carriers is further increased, and the working voltage of the device is reduced.
When both electron transport layers/hole blocking layers on both sides of the light emitting layer contain spirobifluorene structures, the same fragments are contained, so that the LUMO energy level difference between adjacent organic layers can be reduced, the carrier transmission is further increased, and the working voltage of the device is reduced.
It can be understood that the blue light organic electroluminescent device of the present invention comprises a substrate, and an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode sequentially disposed on the substrate.
A further embodiment of the present invention provides a display device including the blue organic electroluminescent device described in the above embodiment.
The following describes the technical scheme of the present invention with reference to some specific embodiments:
some examples of spirobifluorene derivatives
The crystallinity of each of the above spirobifluorene derivatives was tested:
The preparation method of the spirobifluorene derivative is characterized by comprising the following steps of:
Ultrasonic processing is carried out on a white glass plate in a cleaning agent, washing is carried out in deionized water, ultrasonic degreasing is carried out in an acetone-ethanol mixed solvent, and baking is carried out in a clean environment until moisture is completely removed;
Placing the above white glass substrate in a vacuum chamber, vacuumizing to 1× -5～1×10-6 Pa, depositing spirobifluorene derivatives with various structures of 50nm on the white glass substrate, forming a single-layer film on the white glass substrate, and packaging for use.
The above-mentioned white glass substrate having a single-layer film formed thereon was stored at 85℃for various times, and crystallization of the film was observed, and the results are shown in Table 1 below.
TABLE 1
From the above table, it is shown that the spirobifluorene derivative has good stability after being stored at high temperature for 48 hours without crystallization.
In the structure of the spirobifluorene derivative, two fluorenes are in orthogonal three-dimensional space structures, and the rigid three-dimensional structure can avoid pi-pi accumulation among molecules, so that the accumulation of materials is effectively prevented, the crystallization (good space configuration) of the materials can be restrained to a certain extent, and the luminous performance is improved.
Some examples of homologs of anthracene or isomers of anthracene
The homologs of some of the anthracene used in the examples or isomer structures of anthracene are shown in table 2 below.
TABLE 2
1) Calculating electron cloud distribution in the molecular structure of the homolog of the anthracene or the isomer of the anthracene:
specifically calculated using the computational chemistry software "Spartan' 18". The energy level and electron cloud distribution of the equilibrium geometry at the ground state at the calculated level were calculated using the DFT (Density Functional Theory) method for B3LYP/6-31 g. The results are shown in Table 3 below.
TABLE 3 Table 3
The electron cloud of the isomer of anthracene is distributed in the plane of anthracene, and electrons are difficult to delocalize to peripheral groups. And, by simulating and calculating that the energy levels of the isomers are similar, it is shown that the isomers of anthracene have similar electrical characteristics.
2) The photoluminescence spectrum of the anthracene isomer was measured:
The test results of photoluminescence spectra of two of the above-mentioned BH-4 formulas, formula 1 and formula 2, were presented separately, and BH-4 formed by mixing formula 1 and formula 2 are shown in FIG. 1. From the spectral data of fig. 1, it is shown that the monomer has similar spectral properties to the isomeric system and that no exciplex is formed, avoiding spectral red-shifting.
The luminescence spectra of the light of the BH-1, the BH-2, the BH-3 and the BH-5, which are obtained by the two structural formulas in BH-1, BH-2, BH-3 and BH-5 which are singly compounded and compounded by the monomers, are tested in the mode, and the results are similar to the results, and no exciplex is formed after the two monomers in BH-1, BH-2, BH-3 and BH-5 are compounded, so that the spectral red shift is avoided.
3) The crystallinity of the anthracene isomer was tested:
preparing a single-layer film from the isomer of each anthracene, wherein the preparation method comprises the following steps:
Ultrasonic processing is carried out on a white glass plate in a cleaning agent, washing is carried out in deionized water, ultrasonic degreasing is carried out in an acetone-ethanol mixed solvent, and baking is carried out in a clean environment until moisture is completely removed;
Placing the above white glass substrate in a vacuum chamber, vacuumizing to 1× -5～1×10-6 Pa, depositing 50nm of anthracene isomer with various structures on the white glass substrate, forming a single-layer film on the white glass substrate, and packaging for use.
The above-mentioned white glass substrate having a single-layer film formed thereon was stored at 85 ℃ for various periods of time, and crystallization of the film was observed, and the results are shown in table 4 below (in table 4, the ratio of each structural formula 1 to structural formula 2 is the mass ratio).
TABLE 4 Table 4
As can be seen from table 4, the single-component anthracene unit in the individual anthracene isomer has a large planar structure, and the structure makes the molecular structure tend to be planar, so that pi-pi stacking is easily formed between molecules, and the material is accumulated, and crystallization is further initiated, so that the pore blocking phenomenon is caused in the mass production process. The material system formed by matching two homologs or isomers of anthracene can not generate crystallization phenomenon after long-time high-temperature storage, thereby solving the problem of crucible hole blockage of mass production materials.
Further, the compound crystallinity analysis of two structural formulas in BH-1, BH-3 and BH-5 is tested in the manner, and the obtained result is similar to the result, and the material system formed by matching the homologs or isomers of anthracene can not generate crystallization phenomenon after long-time high-temperature storage.
Some embodiments of blue-light organic electroluminescent devices
Examples
The structure of the device comprises an indium tin oxide ITO layer on a glass substrate as an anode, a hole injection layer HIL (5-30 nm), a hole transport layer HTL (100-2000 nm), an electron blocking layer EBL (5-100 nm), a light emitting layer EML (20-100 nm), a hole blocking layer HBL (5-100 nm), an electron transport layer ETL (20-100 nm), an electron injection layer EIL (1-10 nm) and a cathode.
Specifically, the optional materials of each functional layer are as follows, but not limited to:
HIL may be an inorganic oxide such as MoO 3, F4-TCNQ, HAT-CN, etc., but is not limited thereto.
HTL: arylamine or carbazole materials having hole transporting property such as NPB, m-MTDATA, TPD, etc., or spirobifluorene derivatives in the present invention, but not limited thereto.
EBL aromatic amines or carbazole materials having hole transport properties, such as mCBP, tris-PCz, etc., or spirobifluorene derivatives in the present invention, but are not limited thereto.
Host: AND, TBADN, MADN, or homologs of the anthracene or isomers of the anthracene in the present invention.
DOpant: dpvbi, DPAVB, DSA-Ph, etc.
The hbl: hole blocking layer is generally an aromatic heterocyclic compound such as BCP, bphen, etc., or a spirobifluorene derivative in the present invention, but is not limited thereto.
The ETL: electron transporting layer is generally an aromatic heterocyclic compound such as TPBi, bphen, etc., or a spirobifluorene derivative in the present invention, but is not limited thereto.
EIL is generally an alkali metal or metal, liF, yb, liQ, etc., but is not limited thereto.
The preparation process of the device comprises the following steps:
the preparation process of the organic electroluminescent device in the embodiment of the invention is as follows:
(1) Ultrasonically treating a glass plate with ITO in a cleaning agent, flushing in deionized water, ultrasonically degreasing in an acetone-ethanol mixed solvent, and baking in a clean environment until water is completely removed;
(2) Placing the glass substrate with the anode in a vacuum cavity, vacuumizing to 1X 10 -5～1×10-6 Pa, and vacuum evaporating a hole injection material on the anode layer film to form the hole injection material;
(3) Evaporating a hole transport material on the hole injection layer to form a hole transport layer;
(4) Evaporating an electron blocking layer of the hole transport member on the hole transport layer by a vacuum evaporator;
(5) Vacuum evaporating a light-emitting layer of the device on the electron blocking layer, wherein the light-emitting layer comprises a host material and a guest material, and the weight ratio of the host material to the guest material is 97:3 by utilizing a multi-source co-evaporation method;
(6) Vacuum evaporating a hole blocking layer of the device on the light emitting layer;
(7) Vacuum evaporating an electron transport layer of the device on the hole blocking layer;
(8) Vacuum evaporating LiF with the thickness of 1nm on an Electron Transport Layer (ETL) as an electron injection layer;
(9) An Al layer is evaporated on the electron injection layer to serve as a cathode of the device.
With the above embodiments, the following materials were vapor-deposited on the different functional layers to produce the following organic EL devices, and specific materials are shown in table 5 below.
TABLE 5
Some of the materials used in table 5 above are as follows:
in the above embodiments, when the HTL layer, the EBL layer, the HBL layer, and the ETL layer each contain the spirobifluorene derivative in the present technical solution in the organic electroluminescent device, the schematic structures of the HTL layer, the EBL layer, the EML layer, the HBL layer, and the ETL layer in the device are shown in fig. 2.
In the organic electroluminescent device, when the HTL layer, the EBL layer and the HBL layer each contain the spirobifluorene derivative in the present technical solution and the ETL layer does not contain the spirobifluorene derivative, the structure of the HTL layer, the EBL layer, the EML layer, the HBL layer and the ETL layer in the device is schematically shown in fig. 3.
In the organic electroluminescent device, when the spirobifluorene derivative in the technical scheme is contained in each of the EBL layer, the HBL layer and the ETL layer and the HTL layer is not contained in each of the EBL layer, the HBL layer, the EML layer, the HBL layer and the ETL layer in the device, the schematic structure of each is shown in fig. 4.
In the organic electroluminescent device, when the HTL layer, the EBL layer and the ETL layer each contain the spirobifluorene derivative in the present technical solution and the HBL layer does not contain the spirobifluorene derivative, a schematic structure of the HTL layer, the EBL layer, the EML layer, the HBL layer and the ETL layer in the device is shown in fig. 5.
In the organic electroluminescent device, when the spirobifluorene derivative in the technical scheme is contained in each of the HTL layer, the ETL layer and the HBL layer and the EBL layer is not contained in each of the layers, the schematic structures of the HTL layer, the EBL layer, the EML layer, the HBL layer and the ETL layer in the device are shown in fig. 6.
The organic light emitting diode manufactured by the above method, in which each layer was a ：ITO/HIL(10nm)/HTL(100nm)/EBL(10nm)/Host1,Host2：Dopant(1：1,3wt％,20nm))/HBL(5nm)/ETL：LiQ(1:1,30nm)/EIL(1nm)/ cathode (100 nm) in a device, and the driving voltage and the light emitting efficiency were measured at a constant current density of 15mA/cm 2, and the results are shown in table 6.
TABLE 6
| Examples | Voltage (V) | Efficiency of | Life span | CIEx | CIEy |
| Example 1 | 94.23% | 110.59% | 113.24% | 0.134 | 0.120 |
| Example 2 | 95.35% | 109.26% | 108.18% | 0.134 | 0.125 |
| Example 3 | 93.62% | 105.85% | 107.86% | 0.133 | 0.125 |
| Example 4 | 93.54% | 108.45% | 109.41% | 0.135 | 0.124 |
| Example 5 | 94.89% | 107.91% | 108.83% | 0.135 | 0.124 |
| Example 6 | 97.72% | 101.52% | 103.76% | 0.135 | 0.121 |
| Example 7 | 102.30% | 104.43% | 103.68% | 0.135 | 0.113 |
| Example 8 | 99.15% | 102.94% | 104.22% | 0.134 | 0.121 |
| Example 9 | 99.27% | 101.73% | 101.66% | 0.134 | 0.120 |
| Example 10 | 100.71% | 102.89% | 102.06% | 0.134 | 0.120 |
| Example 11 | 94.75% | 107.23% | 106.87% | 0.133 | 0.121 |
| Example 12 | 101.25% | 101.04% | 99.01% | 0.135 | 0.123 |
| Example 13 | 99.27% | 101.73% | 100.66% | 0.134 | 0.120 |
| Example 14 | 100.71% | 100.89% | 99.06% | 0.134 | 0.120 |
| Example 15 | 100.00% | 100.00% | 100.00% | 0.134 | 0.119 |
Note that the voltage, efficiency and lifetime data were set to 100% using the data of example 15 as a reference.
It should be understood that the foregoing examples of the present invention are provided merely for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention, and that various other changes and modifications may be made therein by one skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims.
Claims (10)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111225846.1A CN113991029B (en) | 2021-10-21 | 2021-10-21 | A blue light organic electroluminescent device and a display device containing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111225846.1A CN113991029B (en) | 2021-10-21 | 2021-10-21 | A blue light organic electroluminescent device and a display device containing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113991029A CN113991029A (en) | 2022-01-28 |
| CN113991029B true CN113991029B (en) | 2025-01-10 |
Family
ID=79739888
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111225846.1A Active CN113991029B (en) | 2021-10-21 | 2021-10-21 | A blue light organic electroluminescent device and a display device containing the same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113991029B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118450737A (en) * | 2024-04-30 | 2024-08-06 | 京东方科技集团股份有限公司 | Light emitting device and display substrate |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104557856A (en) * | 2014-12-31 | 2015-04-29 | 南京邮电大学 | Preparation method for 9,9-diaryl thiophene xanthene-10,10-dioxide |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070126347A1 (en) * | 2005-12-01 | 2007-06-07 | Eastman Kodak Company | OLEDS with improved efficiency |
| US8206842B2 (en) * | 2009-04-06 | 2012-06-26 | Global Oled Technology Llc | Organic element for electroluminescent devices |
| US9187493B2 (en) * | 2012-08-14 | 2015-11-17 | Nippon Kayaku Kabushiki Kaisha | Heterocyclic compound and use thereof |
| US11746283B2 (en) * | 2017-06-30 | 2023-09-05 | Transitions Optical, Ltd. | Silole and germole fused ring photochromic compounds |
-
2021
- 2021-10-21 CN CN202111225846.1A patent/CN113991029B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104557856A (en) * | 2014-12-31 | 2015-04-29 | 南京邮电大学 | Preparation method for 9,9-diaryl thiophene xanthene-10,10-dioxide |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113991029A (en) | 2022-01-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR102254393B1 (en) | Organic electroluminescent device and its manufacturing method | |
| KR102053569B1 (en) | Multicyclic compound and organic light emitting device comprising the same | |
| CN114914372B (en) | An organic electroluminescent device | |
| CN102437290B (en) | A kind of display of organic electroluminescence blue-light device and preparation method thereof | |
| CN113097400B (en) | Organic light emitting diode structure and display device | |
| KR20190055122A (en) | Organic electroluminescent device | |
| CN110492007B (en) | Acridine compound and application thereof in organic electroluminescent device | |
| JP7685498B2 (en) | Organic electroluminescent device | |
| KR20170118113A (en) | Phosphorescent compound, manufacturing method and organic light emitting diode device | |
| CN107452886A (en) | A kind of laminated film and Organic Light Emitting Diode and preparation method thereof | |
| KR102317277B1 (en) | Organic electroluminescent device comprising carbazole and pyridine constituent unit materials | |
| CN106810569A (en) | A kind of carboline trisubstituted derivative and its application | |
| CN111788708A (en) | Organic electroluminescent element | |
| CN111834537A (en) | Organic electroluminescent device comprising light extraction layer | |
| CN107428641B (en) | Organic compound and organic electroluminescence element containing the organic compound | |
| CN103570712B (en) | The organic light emitting diode device of phosphorescent compound and this phosphorescent compound of use | |
| CN110964009B (en) | Compound containing phenanthroline structure, application thereof and organic electroluminescent device | |
| CN115477939B (en) | Organic electroluminescent composition, organic electroluminescent device and display device containing the same | |
| CN113991029B (en) | A blue light organic electroluminescent device and a display device containing the same | |
| CN103848857B (en) | Phosphorescent compound and organic light emitting diode device using the same | |
| CN115884652A (en) | Organic light-emitting device and panel based on spirofluorene xanthene | |
| CN113054126A (en) | Polycyclic condensed organic boron semiconductor material and OLED device application | |
| CN118591204A (en) | A light emitting device, a display panel and a display device including the same | |
| KR101779914B1 (en) | Naphthalene derivatives and organic light-emitting diode including the same | |
| JP7539865B2 (en) | Organic electroluminescent device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |