A phenanthroline compound containing a benzo five-membered nitrogen heterocycle, an organic electroluminescent device, and a display or lighting device

Abstract

The invention relates to the technical field of organic photoelectric material preparation, in particular to a phenanthroline compound containing a benzo five-membered nitrogen heterocycle, an organic electroluminescent device and a display or lighting device. The phenanthroline compound of the invention contains a benzo five-membered nitrogen heterocycle, and the phenanthroline structural fragment is modified with an aromatic group, so that the compound has excellent luminous efficiency and good thermal stability; at the same time, the phenanthroline compound containing a benzo five-membered nitrogen heterocycle provided by the invention can largely limit the lateral dispersion of electrons and improve the longitudinal mobility. When used in a device, the organic light-emitting device can effectively have a lower driving voltage and maintain voltage stability, and the luminous efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of organic photoelectric material preparation, and in particular to a phenanthroline compound containing a benzo five-membered nitrogen heterocycle, an organic electroluminescent device, and a display or lighting device. Background Art

[0002] Organic light-emitting diodes (OLEDs), also known as organic electroluminescent devices, are a technology that applies voltage to organic electroluminescent elements to inject holes from the anode and electrons from the cathode into the light-emitting layer respectively. The injected holes and electrons recombine to form excitons, resulting in luminescence. It can convert electrical energy into light energy through organic light-emitting materials.

[0003] At high brightness, the organic light-emitting materials in organic electroluminescent diodes will age over time, which limits the application range of OLED materials. In order to improve the service life of OLED display panels, the existing technology stacks multiple layers of OLED devices and connects multiple OLED devices in series through a charge generation layer. When current passes through, a part of the holes and electrons recombine and emit light in the first light-emitting layer, and the remaining holes and electrons pass through the CGL and recombine and emit light again in the second light-emitting layer.

[0004] Tandem OLED devices have the advantages of high brightness, low power consumption, and long life. However, as the use time of tandem OLED devices increases, the metals and electrons in the charge generation layer between the light-emitting layers tend to disperse laterally, affecting the longitudinal mobility of electrons. At the same time, it will cause the stability of OLED devices to decrease, thereby limiting the luminous efficiency and service life of the devices.

[0005] Therefore, it is necessary to continue to work hard to develop organic light-emitting devices with low voltage drive, high luminous efficiency and high durability, and to find suitable OLED optoelectronic functional materials for OLED devices to solve the above problems. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a phenanthroline compound containing a benzo five-membered nitrogen heterocycle, an OLED having the compound, and a display or lighting device. The provided phenanthroline compound contains a benzo five-membered nitrogen heterocycle, and the phenanthroline structural fragment is limited to be modified with an aromatic group, so that the compound has excellent luminous efficiency and good thermal stability. At the same time, the phenanthroline compound containing a benzo five-membered nitrogen heterocycle provided by the present invention can largely limit the lateral dispersion of electrons and improve the longitudinal mobility, so that the phenanthroline compound containing a benzo five-membered nitrogen heterocycle is used in an organic electroluminescent device, so that the device can have both high efficiency and long service life.

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

[0008] The present invention provides a phenanthroline compound containing a benzo five-membered nitrogen heterocycle, wherein the phenanthroline compound has a structure shown in the following formula I:

[0009] ;

[0010] Wherein, R1-R8 are each independently selected from at least one of hydrogen, deuterium, C6-C30 aryl, C6-C36 N heteroaryl and the group shown in Formula 2 , R1-R8 are not hydrogen at the same time and at least one is selected from the group shown in Formula 2; in Formula 2, X1 is selected from NR a or O atoms, R a is selected from C6-C30 aryl; R9 is selected from hydrogen, C6-C30 aryl, substituted or unsubstituted C3-C36 heteroaryl; when there is a substituent, the substitution is selected from C6-C12 aryl, and the heteroatom is one or more of N, O, and S; R 10 is hydrogen or a condensed phenyl group, Indicates the connection site.

[0011] Preferably, at least one of R1-R8 is selected from phenyl or pyridyl.

[0012] Preferably, 1 to 3 substituents in R1-R8 are selected from phenyl or pyridyl.

[0013] Preferably, R9 is selected from hydrogen, deuterium, phenyl, dibenzofuranyl, dibenzothienyl, benzoxazolyl, phenyl-substituted benzimidazolyl; R a is hydrogen or aryl.

[0014] According to one or more embodiments, the present invention provides a phenanthroline compound containing a benzo five-membered nitrogen heterocycle, selected from any one of the chemical structures shown below:

[0015] .

[0016] The present invention also provides a use of the above-mentioned device in an organic electroluminescent device.

[0017] The present invention also provides an organic electroluminescent device, the organic electroluminescent device comprising:

[0018] a first electrode;

[0019] a second electrode; and

[0020] an organic layer, wherein the organic layer is located between the first electrode and the second electrode;

[0021] The organic layer includes the phenanthroline compound containing a benzo five-membered nitrogen heterocycle as described above.

[0022] Preferably, at least one of the organic layers is a charge generation layer or an electron transport layer.

[0023] Preferably, the charge generation layer is an n-type charge generation layer.

[0024] Preferably, the n-type charge generation layer is composed of a metal or an n-type doped organic material, wherein the metal is selected from Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Sm, Eu, Tb, Dy or Yb.

[0025] The present invention further provides an organic electroluminescent device, comprising:

[0026] a first electrode;

[0027] a second electrode;

[0028] A first light-emitting portion of the first light-emitting layer, which is located between the first electrode and the second electrode;

[0029] A second light-emitting portion of the second light-emitting layer, which is located between the second electrode and the first light-emitting portion; and

[0030] a first charge generation layer located between the first light emitting portion and the second light emitting portion;

[0031] At least one of the first light-emitting portion, the second light-emitting portion, or the first charge generation layer comprises a phenanthroline compound having a structure of Formula I.

[0032] The present invention also provides a composition, which comprises a phenanthroline compound containing a benzo five-membered nitrogen heterocycle as described in formula (I).

[0033] The present invention also provides a preparation, which comprises a phenanthroline compound containing a benzo five-membered nitrogen heterocycle having a structure as shown in the above formula (I) or the above composition and at least one solvent. The solvent is not particularly limited, and can be used as unsaturated hydrocarbon solvents such as toluene, xylene, mesitylene, tetralin, decalin, bicyclohexane, n-butylbenzene, sec-butylbenzene, tert-butylbenzene, carbon tetrachloride, chloroform, dichloromethane, dichloroethane, chlorobutane, bromobutane, chloropentane, bromopentane, hexyl chloride, bromohexane, chlorocyclohexane, bromocyclohexane, halogenated unsaturated hydrocarbon solvents such as chlorobenzene, dichlorobenzene, trichlorobenzene, ether solvents such as tetrahydrofuran, tetrahydropyran, and ester solvents such as alkyl benzoate.

[0034] The organic electroluminescent device of the present invention can be used in an OLED lighting or display device.

[0035] The present invention also provides a display or lighting device, which comprises one or more of the organic electroluminescent devices described above.

[0036] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0037] The phenanthroline compound containing a benzo five-membered nitrogen heterocycle of the present invention comprises an aromatic group and a benzo nitrogen heterocycle fragment, so that the electrons of the nitrogen atoms on the phenanthroline structure are more abundant, and the compound has excellent electron transport properties. At the same time, the compound has a fine-tuning effect on the energy band gap, and can minimize the energy level difference between the n-type charge generation layer and the p-type charge generation layer, thereby increasing the electron injection amount of the light-emitting portion. At the same time, the phenanthroline compound containing a benzo five-membered nitrogen heterocycle provided by the present invention is coordinated with a doped metal, and can largely limit the lateral dispersion of electrons, thereby increasing the longitudinal mobility. When the compound is used in a device, the organic light-emitting device can effectively have a lower driving voltage and maintain voltage stability, thereby increasing the luminous efficiency and service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a cross-sectional schematic diagram of an organic electroluminescent device structure shown in the present invention;

[0039] In the figure: 00, anode; 01, hole injection layer; 02, first hole transport layer; 03, first light-emitting auxiliary layer; 04, first light-emitting layer; 05, first hole blocking layer; 06, first electron transport layer; 07, first electron injection layer; 08, N-type charge generation layer; 09, P-type charge generation layer; 10, second light-emitting auxiliary layer; 11, second light-emitting layer; 12, second hole blocking layer; 13, second electron transport layer; 14, second electron injection layer; 15, cathode layer; 16, covering layer. DETAILED DESCRIPTION

[0040] The following will be described clearly and completely in conjunction with the technical solutions of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0041] The aryl group of the present invention refers to a general term for a monovalent group after removing a hydrogen atom from the aromatic core carbon of an aromatic hydrocarbon molecule, which can be a monocyclic aryl group or a condensed ring aryl group, and the aryl group can be an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. Examples may include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthyl, anthracenyl, phenanthrenyl or pyrenyl, but are not limited thereto. Aryl or aromatic group-as used herein, non-condensed and condensed systems are considered. Aryl can be an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. Examples of the aryl group include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenanthrene, phenanthrene, fluorene, pyrene, perylene and azulene, with preference given to phenyl, biphenyl, terphenyl, triphenylene, fluorene and naphthalene. Examples of non-fused aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p-tolyl, p-(2-phenylpropyl)phenyl, 4'-methylbiphenyl, 4"-tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesityl and m-quaterphenyl.

[0042] The heteroaryl group of the present invention refers to a general term for a group obtained by replacing one or more aromatic carbon atoms in an aromatic group with a heteroatom, wherein the heteroatom includes but is not limited to oxygen, sulfur, silicon or nitrogen atoms, and the heteroaryl group may be a monocyclic heteroaryl group or a condensed ring heteroaryl group, and may be a heteroaryl group having 6 to 30 carbon atoms, preferably a heteroaryl group having 6 to 20 carbon atoms. Examples may include pyridyl, pyrrolyl, pyridyl, thienyl, furanyl, indolyl, quinolyl, isoquinolyl, benzothienyl, benzofuranyl, benzimidazolyl, benzoxazolyl, dibenzofuranyl, dibenzothienyl, carbazolyl, etc., but are not limited thereto.

[0043] Throughout the specification, unless explicitly described to the contrary, "comprising" any component will be understood to imply the inclusion of other elements, rather than excluding any other elements. In addition, it should be understood that throughout the specification, when an element such as a layer, film, region or substrate is referred to as being "on" or "above" another element, it can be "directly on" another element, or there may be intervening elements. In addition, "on..." or "above..." means being located above the target portion, and does not necessarily mean being located above according to the direction of gravity.

[0044] An object of the present invention is to provide an organic electroluminescent device, which comprises: a first electrode; a second electrode, wherein the first electrode is on the substrate; an organic layer, wherein the organic layer is located between the first electrode and the second electrode; and the organic layer comprises a phenanthroline compound containing a benzo five-membered nitrogen heterocycle as described in formula (I).

[0045] The substrate of the present invention can be any substrate used in a typical organic light-emitting device. It can be a glass or transparent plastic substrate, or a substrate of an opaque material such as silicon or stainless steel, or a flexible PI film. Different substrates have different mechanical strengths, thermal stability, transparency, surface smoothness, and waterproofness. Depending on the properties of the substrate, the use direction is different.

[0046] As materials for the hole injection layer, the hole transport layer, the electron injection layer, and the light emitting layer, any material can be selected from known related materials used for OLED devices.

[0047] The present invention is described in detail below in conjunction with specific examples. Synthesis Examples All raw materials and solvents are commercially available unless otherwise specified, and the solvents are used directly without further treatment.

[0048] Example

[0049] Example 1: Synthesis of Compound 001

[0050] Synthesis route:

[0051]

[0052] Synthesis method:

[0053] After compound 001-1 (9.90 g, 33 mmol) was dissolved in 1,4-dioxane (130 mL), 001-2 (10.79 g, 31 mmol), tetrakistriphenylphosphine palladium (1.8 g, 1.5 mmol) and potassium carbonate (12.8 g, 93 mmol) were added thereto, and the resultant was stirred at 100 ° C for 6 hours. After the reaction was terminated, the resultant was cooled to room temperature and extracted with distilled water and ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, and then filtered and concentrated. Using ethyl acetate and hexane as a developing solvent, the concentrated residue was purified using column chromatography to obtain the target compound 001.

[0054] The structure of the test target product 001 was analyzed by liquid chromatography-mass spectrometry (LC-MS) (M+): the theoretical value was 524.20 and the test value was 524.58.

[0055] Example 2: Synthesis of Compound 004

[0056] Compound 004 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (M+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 600.23 and the test value was 600.67.

[0057] Example 3: Synthesis of Compound 007

[0058] Compound 007 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (Μ+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 676.26 and the test value was 676.88.

[0059] Example 4: Synthesis of Compound 014

[0060] Referring to the synthesis steps and reaction conditions of Example 1, compound 014 was synthesized and analyzed by liquid chromatography-mass spectrometry to obtain LC-MS (m / z) (Μ+): the theoretical value was 650.25 and the test value was 650.71.

[0061] Example 5: Synthesis of Compound 025

[0062] Referring to the synthesis steps and reaction conditions of Example 1, compound 025 was synthesized, and the LC-MS (m / z) (Μ+) was obtained by liquid chromatography-mass spectrometry analysis: the theoretical value was 525.20, and the test value was 525.68.

[0063] Example 6: Synthesis of Compound 032

[0064] Referring to the synthesis steps and reaction conditions of Example 1, compound 032 was synthesized, and the LC-MS (m / z) (Μ+) was obtained by liquid chromatography-mass spectrometry analysis: the theoretical value was 602.22, and the test value was 602.64.

[0065] Example 7: Synthesis of Compound 036

[0066] Referring to the synthesis steps and reaction conditions of Example 1, compound 036 was synthesized and analyzed by liquid chromatography-mass spectrometry to obtain LC-MS (m / z) (Μ+): the theoretical value was 676.26 and the test value was 676.72.

[0067] Example 8: Synthesis of Compound 058

[0068] Compound 058 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (Μ+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 677.26 and the test value was 677.82.

[0069] Example 9: Synthesis of Compound 061

[0070] Referring to the synthesis steps and reaction conditions of Example 1, compound 061 was synthesized and analyzed by liquid chromatography-mass spectrometry to obtain LC-MS (m / z) (Μ+): the theoretical value was 651.24 and the test value was 651.80.

[0071] Example 10: Synthesis of Compound 064

[0072] Compound 064 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (Μ+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 678.25 and the test value was 678.81.

[0073] Example 11: Synthesis of Compound 066

[0074] Compound 066 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (Μ+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 716.27 and the test value was 716.83.

[0075] Example 12: Synthesis of Compound 068

[0076] Referring to the synthesis steps and reaction conditions of Example 1, compound 068 was synthesized and analyzed by liquid chromatography-mass spectrometry to obtain LC-MS (m / z) (Μ+): the theoretical value was 766.27 and the test value was 766.89.

[0077] Example 13: Synthesis of Compound 070

[0078] Referring to the synthesis steps and reaction conditions of Example 1, compound 070 was synthesized and analyzed by liquid chromatography-mass spectrometry to obtain LC-MS (m / z) (Μ+): the theoretical value was 642.21 and the test value was 642.69.

[0079] Example 14: Synthesis of Compound 072

[0080] Referring to the synthesis steps and reaction conditions of Example 1, compound 072 was synthesized and analyzed by liquid chromatography-mass spectrometry to obtain LC-MS (m / z) (Μ+): the theoretical value was 707.20 and the test value was 707.82.

[0081] Example 15: Synthesis of Compound 074

[0082] Compound 074 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (Μ+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 690.24 and the test value was 690.82.

[0083] Example 16: Synthesis of Compound 083

[0084] Compound 083 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (M+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 816.29 and the test value was 816.90.

[0085] Example 17: Synthesis of Compound 099

[0086] Compound 099 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (Μ+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 843.30 and the test value was 843.96.

[0087] Example 18: Synthesis of Compound 102

[0088] Compound 102 was synthesized by referring to the synthesis steps and reaction conditions of Example 1. The LC-MS (m / z) (Μ+) was analyzed by liquid chromatography-mass spectrometry: the theoretical value was 844.30 and the test value was 844.92.

[0089] Several examples of the application of the phenanthroline compound containing a benzo five-membered nitrogen heterocycle in OLED devices are listed below to further illustrate the beneficial effects of the compound of the present invention. The materials used in the examples are purchased from commercial sources or synthesized by the user.

[0090] Fabrication of OLED devices:

[0091] As a reference preparation method for a device embodiment, the present invention evaporates 50-500nm ITO / Ag / ITO on an alkali-free glass substrate as an anode, evaporates a hole injection layer (5nm-20nm), a hole transport layer (50-150nm), a light-emitting auxiliary layer (5-120nm), a light-emitting layer (20-50nm), a hole blocking layer (1-20nm), an electron transport layer (20-80nm), and an electron injection layer (1-10nm) on the anode, and then co-evaporates Mg and Ag (weight ratio 1:9, 100-150nm) to make a semi-transparent cathode, and then evaporates a cover layer compound. Finally, the light-emitting device is encapsulated using an epoxy resin adhesive in a nitrogen atmosphere.

[0092] In a preferred specific embodiment, the structure of the OLED device provided by the present invention is: first, use an ultrasonic cleaner to wash the alkali-free glass substrate with isopropanol for 15 minutes, and then perform UV ozone cleaning in the air for 30 minutes. The treated substrate is vacuum-deposited with ITO / Ag / ITO 100nm as an anode, and then a hole injection layer (HT1:PD, 10nm, 2%), a hole transport layer (HT1, 130nm), a light-emitting auxiliary layer (BP1, 5nm), a light-emitting layer (main material: doping material = BH1: BD1 (weight ratio 98:2, 30nm)), a hole blocking layer (compound HB1, 5nm), an electron transport layer (compound 1-001: Liq=1:1, 30nm), and an electron injection layer (Yb, 1nm) are sequentially stacked and evaporated, and Mg and Ag (weight ratio 10:1, 15nm) are co-evaporated to make a semi-transparent cathode, and then compound CPL (65nm) is evaporated as a covering layer. Finally, the light emitting device is encapsulated with epoxy resin adhesive in a nitrogen atmosphere, which is recorded as Application Example 1. The molecular structure formula of the relevant material is as follows (particularly preferably selected from the following structure, but it does not mean that the present invention is limited to the following structure):

[0093]

[0094] The method provided in the above-mentioned application example 1 was used to prepare application examples 1-2 to application examples 1-18 and comparative example 1, except that the compounds listed in Table 1 were used as the second electron transport material to replace the compound 1-001 in application example 1. The structure of Ref-1 used in the comparative example is as follows:

[0095] Performance evaluation of OLED devices:

[0096] The current of the OLED device at different voltages was tested using a Keithley 2365A digital nanovoltmeter, and the current was then divided by the luminous area to obtain the current density of the OLED device at different voltages. The brightness and radiant energy flux density of the OLED device at different voltages were tested using a Konicaminolta CS-2000 spectroradiometer. Based on the current density and brightness of the OLED device at different voltages, the current density (10 mA / cm 2 ) working voltage Volt and current efficiency (cd / A), BI=E / CIEy, refers to the Blue Index in blue light, and is also a parameter for measuring the luminous efficiency of blue light. E refers to the current efficiency, and CIEy refers to the vertical coordinate color point obtained by bringing the wavelength of the device's luminous half-peak width into the CIE1930 software. The test data is shown in Table 1.

[0097] Table 1 Application examples of electron transport materials and their electron luminescence properties

[0098]

[0099] As can be seen from Table 1, compared with Comparative Example 1, Application Examples 1-1 to 1-18 have lower operating voltage, higher BI luminous efficiency and longer service life. The improvement in performance of each application example is based on the fact that the phenanthroline compound material containing a benzo five-membered nitrogen heterocycle of the present invention has better thermal stability and electron transport capability.

[0100] Second, if Figure 1 As shown, the organic electroluminescent device of the present invention includes, in sequence, an anode 00, a hole injection layer 01, a first hole transport layer 02, a first luminescent auxiliary layer 03, a first luminescent layer 04, a first hole blocking layer 05, a first electron transport layer 06, a first electron injection layer 07, an N-type charge generation layer 08, a P-type charge generation layer 09, a second luminescent auxiliary layer 10, a second luminescent layer 11, a second hole blocking layer 12, a second electron transport layer 13, a second electron injection layer 14, and a cathode layer, and a covering layer 16 is evaporated on the cathode layer 15.

[0101] The manufacturing method of the device is as follows: a glass plate with an ITO transparent conductive layer is ultrasonically treated in a cleaning agent, and then ultrasonically treated in deionized water and a mixed solvent of acetone and ethanol to completely remove moisture, and then the surface is bombarded with a low-energy cation beam; then a hole injection layer 1 (HT1:PD, 10nm, 2%), a first hole transport layer 2 (HT1, 130nm), a first light-emitting auxiliary layer 3 (compound BP1, 5nm), a first light-emitting layer 4 (main material: doping material = BH1: BD1 (weight ratio 98:2, 30nm)), a first hole blocking layer 5 (compound HB1, 5nm), a first electron transport layer 6 (compound ET1: Liq=1:1, 20nm), a first electron injection layer 7 (Yb, 1nm) are evaporated on the anode, and then an N-type charge generation layer 8 (compound 1-001: Yb=99:1, 10nm) and a P-type charge generation layer 9 are evaporated in sequence. (HT1:PD, 10nm, 2%), a second light-emitting auxiliary layer 10 (BP1, 5nm), a second light-emitting layer 11 (host material: doping material = BH1: BD1 (weight ratio 98:2, 30nm), a second hole blocking layer 12 (compound HB1, 5nm), a second electron transport layer 13 (compound 1-001: Liq=1:1, 20nm), a second electron injection layer 14 (Yb, 1nm), and then a Mg:Ag metal electrode layer 15 (Mg:Ag=1:9) is evaporated as a cathode layer, and a capping layer compound (CPL, 65nm) is evaporated on the cathode layer 15 as a capping layer 16.

[0102] The molecular structural formula of the relevant materials refers to the structure of the above-mentioned single-layer device.

[0103] Application Examples 2-2 to 2-18 and Comparative Example 2 were prepared by referring to the method provided in Application Example 2-1, except that the compounds listed in Table 2 were used as n-type charge generation layer materials to replace Compound 1-001 in Application Example 2-1.

[0104] Performance evaluation of OLED devices:

[0105] The current of the OLED device at different voltages was tested using a Keithley 2365A digital nanovoltmeter, and the current was then divided by the luminous area to obtain the current density of the OLED device at different voltages. The brightness and radiant energy flux density of the OLED device at different voltages were tested using a Konicaminolta CS-2000 spectroradiometer. Based on the current density and brightness of the OLED device at different voltages, the current density (10 mA / cm 2) working voltage Volt and current efficiency (cd / A), BI=E / CIEy, refers to the Blue Index in blue light, and is also a parameter for measuring the luminous efficiency of blue light. E refers to the current efficiency, and CIEy refers to the vertical coordinate color point obtained by bringing the wavelength of the device's luminous half-peak width into the CIE1930 software. The test data is shown in Table 2.

[0106] Table 2 N-type charge generation layer application example device and electron luminescence characteristics

[0107]

[0108] It can be seen from Table 2 that, compared with Comparative Example 2-1, Application Examples 2-1 to 2-18 have lower operating voltage, higher BI luminous efficiency and longer service life.

[0109] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A phenanthroline compound containing a benzo five-membered nitrogen heterocycle, characterized in that: The phenanthroline compound is selected from any one of the following chemical structures:

2. Use of the phenanthroline compound containing a benzo five-membered nitrogen heterocycle according to claim 1 in the preparation of an organic electroluminescent device.

3. A preparation, characterized in that The preparation comprises the phenanthroline compound containing a benzo five-membered nitrogen heterocycle as claimed in claim 1 and at least one solvent.

4. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises: a first electrode; a second electrode; and an organic layer, wherein the organic layer is located between the first electrode and the second electrode; The organic layer includes the phenanthroline compound containing a benzo five-membered nitrogen heterocycle as claimed in claim 1.

5. The organic electroluminescent device according to claim 4, characterized in that: At least one of the organic layers is a charge generation layer.

6. The organic electroluminescent device according to claim 5, characterized in that: The charge generation layer is an n-type charge generation layer.

7. The organic electroluminescent device according to claim 6, characterized in that: The n-type charge generation layer is composed of a metal or an n-type doped organic material, wherein the metal is selected from Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Sm, Eu, Tb, Dy or Yb.

8. An organic electroluminescent optical device, characterized in that: include: a first electrode; a second electrode; A first light-emitting portion of the first light-emitting layer, which is located between the first electrode and the second electrode; A second light-emitting portion of the second light-emitting layer, which is located between the second electrode and the first light-emitting portion; and a first charge generation layer located between the first light emitting portion and the second light emitting portion; At least one of the first light-emitting portion, the second light-emitting portion, or the first charge generation layer includes the phenanthroline compound containing a benzo five-membered nitrogen heterocycle as claimed in claim 1.

9. Use of the organic electroluminescent device according to any one of claims 4 to 8 in a display or lighting device.

10. A display or lighting device, characterized in that: The device comprises the organic electroluminescent device as described in any one of claims 4-8.

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