A porphyrin copper derivative and an electroluminescent device thereof

Abstract

The present invention belongs to the field of organic light-emitting materials and semiconductor technology, and relates to a porphyrin copper derivative and an electroluminescent device thereof. The structural formula of the porphyrin copper derivative is:. The middle position of the porphyrin copper derivative is a hydrocarbon group, which reduces the conjugation degree of the porphyrin copper derivative. The emission wavelength of the electroluminescent device prepared based on the porphyrin copper derivative is in the orange light range, which is significantly shorter than the emission wavelength (red light to near infrared light range) of the electroluminescent device prepared by the traditional porphyrin metal derivative. The porphyrin copper derivative of the present invention is used as a sensitizer or guest luminescent material in the light-emitting layer of the electroluminescent device, and the successful preparation of an electroluminescent device with a shorter emission wavelength can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of organic luminescent materials and semiconductors, and in particular relates to a porphyrin copper derivative and an electroluminescent device thereof. Background Art

[0002] In recent years, organic light emitting diodes (OLED) have become a hot research direction in the field of lighting and display due to their excellent characteristics such as self-luminescence, high brightness, high contrast, see-through, wearable, foldable, low energy consumption, wide viewing angle, and low temperature resistance. As an electroluminescent device, the core elements of OLED are the preparation process and the luminescent materials used to achieve luminescence.

[0003] As the industry continues to update and iterate, the preparation process of electroluminescent devices has been continuously tested and revised in practice, and its specific parameters and process conditions have become increasingly stable and mature, and the yield rate has been continuously improved, thereby ensuring the cost and stability of electroluminescent devices. As another core element, the update of luminescent materials is relatively difficult. How to select a luminescent material with superior luminescent performance, pure luminescent color, and long service life is an important task that is both difficult and has great commercial application value.

[0004] At present, OLED devices are mostly realized by a multi-layer functional layer composite method. Its functional layers mainly include hole injection layer, hole transport layer (HTL), hole blocking layer, electron injection layer, electron transport layer (ETL), electron blocking layer and emission material layer (EML). Among them, the emission layer is the most important link in determining the performance of OLED devices. Generally, the luminescent material used in the luminescent layer is composed of a host luminescent material (Host) and a guest luminescent material (Dopant) in a certain proportion. In 2019, Liao and his colleagues proposed the use of exciplex to form a co-host superfluorescent system, that is, the luminescent material is composed of a dual host luminescent material, a sensitizer (Sensitizer), and a guest luminescent material in a certain proportion. The sensitizer plays the role of assisting the guest luminescent material to emit light (Assist Dopant). In order to achieve stable luminescence performance, the host luminescent material usually contains a hole and / or electron transport layer in its structure, has suitable carrier transport performance, and requires its triplet energy level to be higher than that of the sensitizer and the guest luminescent material, so as to ensure that the triplet excitons are confined to the luminescent layer. Therefore, dual host luminescent materials are usually used in combination to achieve high-efficiency luminescence. At the same time, the sensitizer transfers the energy of the singlet excitons and triplet excitons of the sensitizer to the guest luminescent material through Forster energy transfer (FRET), so that the guest luminescent material emits light. In the Forster energy theory, the necessary condition for achieving efficient energy transfer is that the emission spectrum of the donor overlaps well with the emission spectrum of the acceptor. Therefore, the maximum emission wavelength of the donor, that is, the sensitizer, should be less than the maximum emission wavelength of the acceptor guest luminescent material. Under this regulation, the energy transfer between the sensitizer and the guest luminescent material can be guaranteed.

[0005] In recent years, scientists have enhanced the photophysical and electrochemical properties of porphyrin derivatives by chelating porphyrins with other transition metals (such as platinum, manganese, and zinc) and performing side chain modification, making them stand out in the field of optoelectronic material display. The degree of conjugation of existing porphyrin metal derivatives is usually high, so that the emission wavelength of electroluminescent devices prepared as sensitizers or guest luminescent materials is in the range of red to near-infrared wavelengths, that is, the obtained electroluminescent devices are red light devices. At present, it is impossible to prepare electroluminescent devices with lower emission wavelengths based on porphyrin metal derivatives. In order to achieve colored luminescence, luminescent materials with different emission wavelengths need to cooperate with each other. However, this goal cannot be achieved based on existing porphyrin metal derivatives. Summary of the invention

[0006] In order to solve the above problems of the prior art, the present invention provides a porphyrin copper derivative and an electroluminescent device thereof, based on which a luminescent material with a lower emission wavelength and an electroluminescent device thereof can be obtained.

[0007] The present invention is achieved through the following technical solutions:

[0008] A porphyrin copper derivative, the structure of the porphyrin copper derivative is shown in formula (1):

[0009]

[0010] Formula (1)

[0011] Wherein: A is selected from hydrogen, substituted or unsubstituted C 6 ~C 20 The aromatic group, C 1 ~C 10 The alkyl and C 5 ~C 6 Cycloalkyl; L 1 Selected from C 1 ~C 10 Alkyl, C 3 ~C 6 Cycloalkyl and C 1 ~C 10 The alkenyl group.

[0012] Preferably, L 1 is selected from methyl, deuterated methyl, ethyl, n-propyl, isopropyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, cyclohexenyl, vinyl, propenyl and allyl.

[0013] Furthermore, A is selected from substituted or unsubstituted C 6 ~C 20 The aromatic group, C 1 ~C 10 The alkyl and C 5 ~C 6 of a cycloalkyl group.

[0014] Further, A is selected from substituted or unsubstituted phenyl, C 1 ~C 10 The alkyl and C 5 ~C 6 of a cycloalkyl group.

[0015] Further, A is selected from substituted or unsubstituted phenyl and C 1 ~C 10 of alkyl.

[0016] Furthermore, the substituent in the substituted phenyl group is selected from an alkyl group and a cycloalkyl group. When the substituent is a cycloalkyl group, the cycloalkyl group is fused to the phenyl group.

[0017] Preferably, the copper porphyrin derivative is any one of the following compounds 1 to 46:

[0018] .

[0019] The present invention also provides an organic electroluminescent device, comprising a cathode, an anode and an organic layer located between the cathode and the anode, wherein the organic layer comprises a hole transport layer, a light emitting layer and an electron transport layer, wherein the hole transport layer is located between the anode and the light emitting layer, and the electron transport layer is located between the cathode and the light emitting layer;

[0020] The components of the light-emitting layer include a host light-emitting material, a sensitizer and a guest light-emitting material, wherein the sensitizer includes the porphyrin copper derivative described above; or, the components of the light-emitting layer include a host light-emitting material and a guest light-emitting material, wherein the guest light-emitting material includes the porphyrin copper derivative described above.

[0021] Preferably, the host luminescent material includes a HA-type host luminescent material and a HB-type host luminescent material; wherein the HA-type host luminescent material is selected from any one of the following HA01 to HA12; and the HB-type host luminescent material is selected from any one of HB01 to HB10;

[0022] HA type:

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029] HB type:

[0030]

[0031]

[0032]

[0033]

[0034] .

[0035] Preferably, when the components of the light-emitting layer include a host light-emitting material, a sensitizer and a guest light-emitting material, the guest light-emitting material is one of DCJTB, Rubrene, TBPE, DABNA, DBP, A-ADN and B-ADN;

[0036]

[0037] .

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] The middle position of the copper porphyrin derivative of the present invention is a hydrocarbon group (alkyl, cycloalkyl or alkenyl), which reduces the conjugation degree of the copper porphyrin derivative. Studies have found that the emission wavelength of the electroluminescent device prepared based on the copper porphyrin derivative is in the orange light range, which is significantly shorter than the emission wavelength (red light to near infrared light range) of the electroluminescent device prepared by the traditional porphyrin metal derivative. Therefore, the copper porphyrin derivative of the present invention is used as a sensitizer or guest luminescent material in the light-emitting layer of the electroluminescent device, and the successful preparation of an electroluminescent device with a shorter emission wavelength can be achieved. When the porphyrin copper derivative of the present invention is used as a sensitizer to form a light-emitting layer of an electroluminescent device with a host light-emitting material and a guest light-emitting material, the light-emitting principle is as follows: the host light-emitting material outputs singlet excitons through Forster energy transfer and triplet excitons through Dexter energy transfer (DET) to the sensitizer, thereby achieving complete energy transfer from the host light-emitting material to the sensitizer; after the sensitizer receives energy, it outputs singlet excitons to the guest light-emitting material through Forster energy transfer, and the singlet excitons of the guest light-emitting material capture triplet excitons through intersystem crossing (ISC), and the triplet excitons quickly release energy while the guest light-emitting material emits light ( Figure 1 ).

[0040] The electroluminescent device of the present invention uses the copper porphyrin derivative as a sensitizer or guest luminescent material in the luminescent layer, so that the emission wavelength of the electroluminescent device is within the orange light range, and the electroluminescent device with a shorter emission wavelength is successfully prepared. At the same time, compared with the electroluminescent device prepared by the traditional porphyrin metal derivative, the electroluminescent device of the present invention also has the characteristics of high luminous efficiency, low efficiency roll-off, low starting voltage and long working life. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 It is the energy transfer process involved in the light-emitting layer of the electroluminescent device of the present invention, wherein RISC (Reverse Intersystem Crossing) is opposite to ISC.

[0043] Figure 2 The figure is a cross-sectional view of an electroluminescent device according to the present invention.

[0044] Figure 2 Marking Description:

[0045] 1. Substrate, 2. Anode, 3. Hole injection layer, 4. Hole transport layer, 5. Light-emitting layer, 6. Electron transport layer, 7. Electron injection layer, 8. Cathode. DETAILED DESCRIPTION

[0046] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0047] It should be noted that the process equipment or devices not specifically specified in the following embodiments are all conventional equipment or devices in the art.

[0048] It should be noted that the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to define the scope of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the present invention without substantially changing the technical content.

[0049] The present invention provides a porphyrin copper derivative, the structure of the porphyrin copper derivative is shown in formula (1):

[0050]

[0051] Formula (1)

[0052] Wherein: A is selected from hydrogen, substituted or unsubstituted C 6 ~C 20 The aromatic group, C 1 ~C 10 The alkyl and C 5 ~C 6 Cycloalkyl; L 1 Selected from C 1 ~C 10 Alkyl, C 3 ~C 6 Cycloalkyl and C 1 ~C 10 The alkenyl group.

[0053] The substituted or unsubstituted C 6 ~C 20 The aryl group refers to the C 6 ~C 20 The aryl group may be further substituted by a substituent or may not be substituted by a substituent. 6 ~C 20 When the aryl group is substituted by a substituent, the substituent is selected from an alkyl group and a cycloalkyl group. When the substituent is a cycloalkyl group, the cycloalkyl group is fused to the aryl group.

[0054] In the present invention, the term "aryl" refers to a 6-20 membered all-carbon monocyclic or fused polycyclic (i.e., rings sharing adjacent pairs of carbon atoms) group having a conjugated π electron system, preferably containing 6-10 carbon atoms, such as phenyl and naphthyl, more preferably phenyl.

[0055] In the present invention, the term "alkyl" refers to a saturated aliphatic hydrocarbon group, which is a straight chain or branched chain group containing 1 to 10 carbon atoms, preferably a straight chain or branched chain group containing 1 to 4 carbon atoms. Non-limiting examples include methyl, deuterated (D) methyl, ethyl, n-propyl, isopropyl and tert-butyl.

[0056] In the present invention, the term "cycloalkyl" refers to a saturated or partially unsaturated monocyclic or polycyclic hydrocarbon substituent, and the cycloalkyl contains 3 to 10 carbon atoms, preferably 3 to 6 carbon atoms. Non-limiting examples include cyclopropyl, cyclopentyl, cyclohexyl, and cyclohexenyl.

[0057] In the present invention, the term "alkenyl" refers to an unsaturated aliphatic hydrocarbon group, which is a straight chain or branched chain group containing 1 to 10 carbon atoms, preferably a straight chain or branched chain group containing 1 to 4 carbon atoms. Non-limiting examples include vinyl, propenyl and allyl.

[0058] The copper porphyrin derivative of the present invention is any one of the following compounds 1 to 46:

[0059] .

[0060] The present invention also provides an electroluminescent device, comprising a cathode, an anode and an organic layer located between the cathode and the anode, wherein the organic layer comprises a hole transport layer, a light-emitting layer and an electron transport layer, wherein the hole transport layer is located between the anode and the light-emitting layer, and the electron transport layer is located between the cathode and the light-emitting layer.

[0061] In some embodiments of the present invention, the components of the light-emitting layer include a host light-emitting material, a sensitizer and a guest light-emitting material, the sensitizer includes a porphyrin copper derivative as shown in formula (1), and the mass of the sensitizer accounts for 0.1% to 2% of the mass of the entire light-emitting layer.

[0062] In some other embodiments of the present invention, the components of the light-emitting layer include a host light-emitting material and a guest light-emitting material, the guest light-emitting material includes a porphyrin copper derivative as shown in formula (1), and the mass of the guest light-emitting material accounts for 0.5% to 3% of the mass of the entire light-emitting layer.

[0063] The host luminescent material of the present invention as described above adopts a composite host luminescent material, and the composite host luminescent material includes a HA-type host luminescent material and a HB-type host luminescent material. The mass ratio of the HA-type host luminescent material and the HB-type host luminescent material is controlled at (3~4): (7~6). More preferably, the mass ratio of the HA-type host luminescent material and the HB-type host luminescent material is 4:6.

[0064] Among them, the HA type is selected from any one of the following HA01~HA12; the HB type is selected from any one of HB01~HB10.

[0065] HA type:

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072] HB type:

[0073]

[0074]

[0075]

[0076]

[0077]

[0078] The guest luminescent material of the present invention is selected from one of the traditional fluorescent emitters with excellent performance, such as DCJTB, Rubrene, TBPE, DABNA, DBP, A-ADN, and B-ADN, and the mass of the guest luminescent material accounts for 0.5% to 10% of the mass of the entire luminescent layer.

[0079] The structure of the fluorescent emitter involved in the present invention is as follows:

[0080]

[0081]

[0082] A substrate can be set outside the cathode or anode, and the substrate is made of ITO (Indium-Tin Oxide) conductive glass with a certain mechanical strength. In addition, the substrate used as a display can also have a thin film transistor (TFT) array and a specific display image formed by the combination of the thin film transistor array.

[0083] Specifically, the anode may be made of indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO 2 ), zinc oxide (ZnO) and other oxide transparent conductive materials and any combination thereof. The cathode can be made of magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-aluminum (Mg-Al), and magnesium-silver (Mg-Ag).

[0084] In the embodiment of the present invention, the organic layer further includes a hole injection layer and an electron injection layer. The hole injection layer is located between the anode and the hole transport layer, and the electron injection layer is located between the cathode and the electron transport layer.

[0085] Specifically, the material of the hole injection layer is selected from m-MTDATA or F4TCNQ or HATCN. The hole transport layer can be divided into a single-layer hole transport layer and a composite hole transport layer. In order to simplify the structure of the electroluminescent device, the present invention selects any one of the hole transport layer materials NPD, FFD, and 2-TNATA with excellent performance or a combination of at least two of them as a single-layer hole transport layer. The electron transport layer can be realized by using one or more combinations of BCP, Bphen, TAZ, and NTAZ with excellent industry performance. The electron injection layer can be selected from lithium fluoride (LiF), sodium chloride (NaCl), cesium fluoride (CsF), lithium oxide (Li 2 O) or barium oxide (BaO).

[0086] The structure of the hole injection layer material involved in the present invention is as follows:

[0087]

[0088] The structure of the hole transport layer material involved in the present invention is as follows:

[0089]

[0090] The structure of the electron transport layer material involved in the present invention is as follows:

[0091]

[0092]

[0093] The organic layer can be formed on the electrode by vacuum thermal evaporation, spin coating, printing and the like.

[0094] The present invention is described in detail below in conjunction with specific embodiments of the present invention.

[0095] 1. Compound Preparation

[0096] The synthesis process of the copper porphyrin derivative of the present invention is described as follows:

[0097] The present invention uses Rhodobacter sphaeroides 1.2569 disclosed in the document High-yield porphyrin production through metabolic engineering and biocatalysis (https: / / doi.org / 10.1038 / s41587-024-02267-3) as a cell factory for producing porphyrin derivatives, and uses HemH Sa The protein acts as a coupling enzyme to catalyze the formation of porphyrin derivatives into porphyrin copper derivatives. The specific process is as follows.

[0098] Synthesis of compound 4:

[0099]

[0100] The first step is the synthesis of compound 4-1:

[0101] Take a 5 L batch fermentation bioreactor (pH and dissolved oxygen were tested by online dissolved oxygen (DO) probe), add a certain volume of nutrient broth, add 200 mL of concentrated bacterial culture of R. sphaeroides1.2569 strain, add 125 g of 3,4-dimethylmaleimide (first reactant) and 88 g of 1-butyric acid (second reactant), keep the initial working volume at 2.5 L, and add antifoam 204 to prevent foam formation. The temperature in the bioreactor was kept at a constant 35 °C, the fermentation aeration rate was kept at 1.0 VVM (Volume / Culturevolume / Min), the stirring speed was kept at 600 rpm, and the system was automatically injected with ammonia when the pH value was 6.8. After 18 h of cultivation, batch feeding treatment was started, and 500 g / L of concentrated glucose stock solution was added to make the glucose concentration in the bioreactor 15 g / L. After 30 h, the inducer isopropyl-β-D-thiogalactoside (IPTG) was added (final concentration was 1 mM). After 48 h, the glucose concentration was maintained at 5 g / L, and 25 mL of feeding medium (sugar-free fermentation medium) was added every 24 h. During the fermentation process, the fermentation broth was collected every 5 h, and the production of compound 4-1 was monitored by high performance liquid chromatography (HPLC).

[0102] Sampling: Take 200 μL of the fermentation broth, mix with an equal volume of 0.05% acidic acetone aqueous solution, shake vigorously, and centrifuge. Filter the supernatant after centrifugation through a 0.22 μm organic filter membrane, and use the filtrate for HPLC detection.

[0103] When the HPLC spectrum shows that the content of the raw material 3,4-dimethylmaleimide is ≤0.5%, the first step of the reaction is completed.

[0104] Post-treatment: The fermentation broth containing compound 4-1 was centrifuged at high speed, the pH value of the supernatant was adjusted to 9.0 with sodium hydroxide, and the supernatant was allowed to stand at room temperature in the dark for 30 min. Subsequently, the supernatant was collected by centrifugation. Then, a 20% volume fraction of isopropanol aqueous solution was added, mixed thoroughly, and then incubated in the dark at room temperature for 2 h. Centrifuged and the supernatant was collected. Subsequently, an equal volume of a 25% volume fraction of acidic acetone aqueous solution was added, stirred thoroughly, centrifuged, and the precipitate was removed to obtain the remaining solution. A 2% mass fraction of sodium acetate aqueous solution was added to the remaining solution, and the mixture was allowed to stand at low temperature for 15 h. After centrifugation, the supernatant was discarded, and the crystals of compound 4-1 were collected. The crystals were washed with deionized water and n-heptane in turn, and dried to obtain off-white crystalline compound 4-1. The mass of the obtained off-white crystalline compound 4-1 was 156 g, and the content of compound 4-1 was 99% and the yield was 85% by HPLC. LC-MS showed that the molecular weight of compound 4-1 was 623.29.

[0105] Step 2, synthesis of compound 4:

[0106] In a 5 L reactor, add 2.0 L of Tris-HCl buffer (50 mM, pH 7.0), 156 g of compound 4-1, and 20 mL of 5 mM copper chloride stock solution and mix thoroughly. Finally, add 5 μM HemH 28 The reaction was started by adding enzyme. The reaction was continued at 37 °C until the reaction was completed, and 2.0 L of 2% hydrochloric acid in acetone solution was added for reaction, mixed by vortex oscillator, and then centrifuged at high speed for 10 min. The supernatant was filtered through a 0.22 μm organic membrane filter, and the filtrate was concentrated and recrystallized to obtain light yellow compound 4. The mass of light yellow compound 4 was 101 g, the content of compound 4 detected by HPLC was 99%, the yield of compound 4 was 69%, and LC-MS showed that the molecular weight of compound 4 was 684.20.

[0107] The synthesis of other compounds all refers to the synthesis process of compound 4. The first reactant and the second reactant involved in the reaction process are shown in Table 1 and Table 2. The LC-MS and elemental analysis results of the compounds of the present invention are shown in Table 3.

[0108]

[0109]

[0110]

[0111] 2. Electroluminescent Devices

[0112] Based on the copper porphyrin derivative of the present invention, an electroluminescent device is prepared, wherein the copper porphyrin derivative is used as a sensitizer or a guest luminescent material in the electroluminescent device.

[0113] The schematic diagram of the structure of the electroluminescent device used in the experimental process of the present invention is as follows Figure 2 As shown, it comprises a substrate 1, an anode 2, a hole injection layer 3, a hole transport layer 4, a light-emitting layer 5, an electron transport layer 6, an electron injection layer 7 and a cathode 8. The copper porphyrin derivative is used in the light-emitting layer as a sensitizer or a guest light-emitting material to evaluate the performance of the electroluminescent device.

[0114] In the embodiment of the present invention, the preparation method of the electroluminescent device adopts the preparation process technology currently recognized in the industry.

[0115] Comparative Example 1

[0116] The electroluminescent device was prepared as follows:

[0117] Under high vacuum conditions, 25nm thick indium tin oxide was deposited as an anode, 20nm thick m-MTDATA was deposited as a hole injection layer, and 120nm thick NPD was deposited as a hole transport layer on the cleaned substrate conductive glass. After the hole transport layer was deposited, a 40nm thick luminescent layer was prepared. The luminescent layer included a main luminescent material formed by a composite of HA1 and HB1, and a traditional excellent phosphorescent material Ir(piq) 2 (acac) is used as a sensitizer, and the traditional fluorescent emitter DCJTB with excellent performance is used as the guest luminescent material. HA1, HB1, sensitizer, and guest luminescent material are co-evaporated at a mass ratio of 40:60:0.5:5 to form a luminescent layer. On the luminescent layer, BCP is evaporated as an electron transport layer, and the vacuum evaporated film thickness of this material is 26nm. On the electron transport layer, a LiF layer with a film thickness of 16nm is made by a vacuum evaporation device. This layer is the electron injection layer. On the electron injection layer, a Mg-Al (molar ratio Mg: Al=1:9) electrode layer with a film thickness of 50nm is made by vacuum sputtering technology. This layer is the cathode. Finally, the obtained electroluminescent device is evaporated with a cover layer material and then packaged to complete the preparation process of the electroluminescent device.

[0118] Comparative Example 2

[0119] An electroluminescent device was prepared according to the steps of Comparative Example 1, except that the sensitizer Ir(piq) in the light-emitting layer was 2 (acac) replaced by Ir(piq-F) 2 (acac).

[0120] Comparative Example 3

[0121] An electroluminescent device was prepared according to the steps of Comparative Example 1, except that the sensitizer Ir(piq) in the light-emitting layer was 2 (acac) replaced by Ir(m-piq) 2 (acac).

[0122] Comparative Example 4

[0123] An electroluminescent device was prepared according to the steps of Comparative Example 1, except that the sensitizer Ir(piq) in the light-emitting layer was 2 (acac) was replaced by comparative compound A .

[0124] Comparative Example 5

[0125] An electroluminescent device was prepared according to the steps of Comparative Example 1, except that the luminescent layer did not contain a sensitizer, and a conventional phosphorescent material Ir(piq-F) with excellent performance was added. 2 (acac) is used as the guest light-emitting material, and HA1 host light-emitting material, HB1 host light-emitting material and guest light-emitting material are co-evaporated in a mass ratio of 40:60:3 to form a light-emitting layer.

[0126] Comparative Example 6

[0127] An electroluminescent device was prepared according to the steps of Comparative Example 1, except that the light-emitting layer did not contain a sensitizer, and comparative compound A was added as a guest light-emitting material, and the HA1 main light-emitting material, HB1 main light-emitting material, and the guest light-emitting material were co-evaporated in a mass ratio of 40:60:3 to form a light-emitting layer.

[0128] The detailed structures of the electroluminescent devices of Comparative Examples 1 to 6 are as follows:

[0129] Comparative Example 1: Conductive glass / Indium tin oxide (25nm) / m-MTDATA (20nm) / NPD (120nm) / HA1:HB1: Ir(piq) 2 (acac): CDJBT=40:60:0.5:5(40nm) / BCP (26nm) / LiF(16nm) / Mg-Al(50nm).

[0130] Comparative Example 2: Conductive glass / Indium tin oxide (25nm) / m-MTDATA (20nm) / NPD (120nm) / HA1:HB1: Ir(piq-F) 2 (acac): CDJBT=40:60:0.5:5(40nm) / BCP (26nm) / LiF(16nm) / Mg-Al(50nm).

[0131] Comparative Example 3: Conductive glass / Indium tin oxide (25nm) / m-MTDATA (20nm) / NPD (120nm) / HA1:HB1: Ir(m-piq) 2 (acac): CDJBT=40:60:0.5:5(40nm) / BCP (26nm) / LiF(16nm) / Mg-Al(50nm).

[0132] Comparative Example 4: Conductive glass / indium tin oxide (25nm) / m-MTDATA (20nm) / NPD (120nm) / HA1:HB1: Comparative compound A: CDJBT=40:60:0.5:5 (40nm) / BCP (26nm) / LiF (16nm) / Mg-Al (50nm).

[0133] Comparative Example 5: Conductive glass / Indium tin oxide (25nm) / m-MTDATA (20nm) / NPD (120nm) / HA1:HB1: Ir(piq-F) 2 (acac)=40:60:3(40nm) / BCP (26nm) / LiF(16nm) / Mg-Al(50nm).

[0134] Comparative Example 6: Conductive glass / indium tin oxide (25nm) / m-MTDATA (20nm) / NPD (120nm) / HA1:HB1:Comparative compound A=40:60:3(40nm) / BCP (26nm) / LiF(16nm) / Mg-Al(50nm).

[0135] The structure of the phosphorescent material involved in the above comparative example is as follows:

[0136]

[0137] Embodiment 1~10:

[0138] The preparation method of Comparative Example 1 was followed, except that the sensitizer Ir(piq) in the light-emitting layer was 2 (acac) are replaced in sequence with the porphyrin copper derivatives described in the present invention: Compound 2, Compound 3, Compound 8, Compound 9, Compound 13, Compound 20, Compound 36, Compound 37, Compound 44, and Compound 45.

[0139] Embodiments 11 to 13

[0140] An electroluminescent device was prepared according to the steps of Comparative Example 4, except that Ir(piq-F) 2 (acac) is replaced with the porphyrin copper derivatives described in the present invention in sequence: Compound 20, Compound 44, and Compound 45.

[0141] The electroluminescent devices of Examples 1 to 13 and Comparative Examples 1 to 6 were tested, and the test data are shown in Table 4.

[0142]

[0143] As shown in Table 4, by comparing Examples 11 to 13 with Comparative Example 5, it can be seen that the electroluminescent device prepared by using the porphyrin copper derivative of the present invention as the guest luminescent material is better than the traditional phosphorescent material Ir(piq-F) with excellent performance. 2 (acac) Compared with the above, the emission wavelength is blue-shifted, and the starting voltage is reduced, PLYQ is increased by about 20%, EQE is increased by more than 20%, and the life span is extended by about 30%. Comparing Examples 11 to 13 with Comparative Example 6, it can be seen that the color coordinates of the electroluminescent device based on the porphyrin copper derivative with an aromatic group in the middle position are in the red light range, while the color coordinates of the electroluminescent device prepared by the porphyrin copper derivative of the present invention as a guest luminescent material are in the orange light range. This shows that, relative to the porphyrin copper derivative with an aromatic group in the middle position, the electroluminescent device emission wavelength prepared by the porphyrin copper derivative of the present invention as a guest luminescent material is blue-shifted, and therefore, an electroluminescent device with a shorter emission wavelength can be prepared based on the porphyrin copper derivative of the present invention as a guest luminescent material. This may be because the degree of conjugation of the porphyrin copper derivative of the present invention is low, which promotes the blue shift of the emission wavelength of the electroluminescent device. At the same time, it can be seen that the electroluminescent device based on the porphyrin copper derivative of the present invention has obvious improvements in start-up voltage, PLYQ, EQE and lifespan compared with the electroluminescent device based on the porphyrin copper derivative with aromatic group in the middle position.

[0144] By comparing Examples 1 to 10 with Comparative Examples 1 to 3, it can be seen that the electroluminescent device prepared using the porphyrin copper derivative of the present invention as a sensitizer has improved start-up voltage, PLYQ, EQE, and thermal stability compared to the electroluminescent devices of Comparative Examples 1 to 3, and the service life is extended, and the emission wavelength is significantly blue-shifted. Specifically, the electroluminescent devices of Examples 1 to 10 of the present invention have an increase of about 25% in PLYQ, an increase of about 30% in EQE, an increase of about 50% in service life, and an effective improvement in overall device efficiency compared to the electroluminescent devices of Comparative Examples 1 to 3.

[0145] Comparing Examples 1 to 10 with Comparative Example 4, it can be seen that compared with the electroluminescent device prepared from the comparative compound A of Comparative Example 4 (the substituent in the compound is an aryl group), the overall efficiency of the electroluminescent device prepared from the porphyrin copper derivatives in Examples 1 to 10 (the substituent in the porphyrin copper derivatives is an alkyl, cycloalkyl or alkenyl group) is significantly improved, indicating that the substituent in the porphyrin copper derivative is an alkyl, cycloalkyl or alkenyl group, which is more conducive to the luminescence of the electroluminescent device. In addition, compared with the electroluminescent device in Comparative Example 4, the emission wavelength of the electroluminescent device in Examples 1 to 10 is blue-shifted from the red light range to the orange light range, that is, the porphyrin copper derivative of the present invention, as a sensitizer, can also realize the preparation of low-emission-wavelength electroluminescent devices. This may be because the porphyrin copper derivative of the present invention has a low degree of conjugation, which causes the emission wavelength of the electroluminescent device to blue-shift. Comparing Examples 1-2 with Examples 7-8, the wavelength (color coordinates in the orange light range) of the light emitted by the electroluminescent device in Examples 1-2 (corresponding to Compounds 2 and 3) is shorter than that in Examples 7-8 (corresponding to Compounds 36 and 37). This may be because the degree of conjugation in the molecules of Compounds 2 and 3 is lower than that of Compounds 36 and 37. This also shows that reducing the degree of conjugation of the compounds used as sensitizers in electroluminescent devices is beneficial to the movement of the emitted light toward the short-wave direction.

[0146] In summary, it can be seen that by using the porphyrin copper derivative of the present invention as a sensitizer or a guest luminescent material, an electroluminescent device with a shorter emission wavelength can be prepared, and the comprehensive performance of the electroluminescent device is improved.

[0147] The present invention utilizes R. sphaeroides 1.2569 as a chassis microorganism to construct an efficient cell factory, and produces porphyrin copper derivatives through coupled enzyme catalysis, which has the advantages of being environmentally friendly and having a high yield.

[0148] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

[0149] Many other changes and modifications may be made without departing from the concept and scope of the present invention.It should be understood that the present invention is not limited to the specific embodiments, and the scope of the present invention is defined by the appended claims.

Claims

1. An organic electroluminescent device, characterized in that: It includes a cathode, an anode and an organic layer located between the cathode and the anode, wherein the organic layer includes a hole transport layer, a light emitting layer and an electron transport layer, wherein the hole transport layer is located between the anode and the light emitting layer, and the electron transport layer is located between the cathode and the light emitting layer; The components of the light-emitting layer include a main light-emitting material, a sensitizer and a guest light-emitting material, and the sensitizer includes a porphyrin copper derivative; or, the components of the light-emitting layer include a main light-emitting material and a guest light-emitting material, and the guest light-emitting material includes a porphyrin copper derivative; Wherein, the structure of the porphyrin copper derivative is shown in formula (1): Formula (1) Wherein: A is selected from substituted or unsubstituted C6~C 20 Aryl, C1~C 10 and C5~C6 cycloalkyl; L1 is selected from C1~C 10 Alkyl, C3~C6 cycloalkyl and C1~C 10 The alkenyl group.

2. The organic electroluminescent device according to claim 1, characterized in that: L1 is selected from the group consisting of methyl, deuterated methyl, ethyl, n-propyl, isopropyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, cyclohexenyl, vinyl, propenyl and allyl.

3. The organic electroluminescent device according to claim 2, characterized in that: A is selected from substituted or unsubstituted phenyl, C1~C 10 The alkyl group is C5~C6 and the cycloalkyl group is C5~C6.

4. The organic electroluminescent device according to claim 3, characterized in that: A is selected from substituted or unsubstituted phenyl and C1~C 10 of alkyl.

5. The organic electroluminescent device according to claim 4, characterized in that: The substituent in the substituted phenyl group is selected from an alkyl group and a cycloalkyl group. When the substituent is a cycloalkyl group, the cycloalkyl group is fused to the phenyl group.

6. The organic electroluminescent device according to claim 1, characterized in that: The porphyrin copper derivative is any one of the following compounds 1 to 46: 。 7. The organic electroluminescent device according to claim 1, characterized in that: The host luminescent material includes a HA-type host luminescent material and a HB-type host luminescent material; wherein the HA-type host luminescent material is selected from any one of the following HA01 to HA12; and the HB-type host luminescent material is selected from any one of HB01 to HB10; HA type: HB type: 。 8. The organic electroluminescent device according to claim 1, characterized in that: When the components of the light-emitting layer include a host light-emitting material, a sensitizer and a guest light-emitting material, the guest light-emitting material is one of DCJTB, Rubrene, TBPE, DABNA, DBP, A-ADN and B-ADN; 。

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