Organic optoelectronic device and display device

Abstract

The organic optoelectronic device includes a positive electrode and a negative electrode facing each other, a light-emitting layer between the positive electrode and the negative electrode, a hole transport layer between the positive electrode and the light-emitting layer, and a hole transport auxiliary layer between the light-emitting layer and the hole transport layer, wherein the light-emitting layer contains a first compound represented by Chemical Formula 1 and a second compound represented by Chemical Formula 2, and the hole transport auxiliary layer contains a third compound represented by Chemical Formula 2. The details of Chemical Formula 1 and Chemical Formula 2 are as defined in the specification.

Description

Technical Field

[0001] Organic optoelectronic devices and display devices have been disclosed. Background Technology

[0002] Organic optoelectronic devices (organic optoelectronic diodes) are devices that can convert electrical energy into light energy and vice versa.

[0003] Based on their working principles, organic optoelectronic devices can be broadly classified into two categories. One category consists of optoelectronic devices that generate electrical energy by separating excitons formed from light energy into electrons and holes and transferring the electrons and holes to different electrodes. The other category consists of light-emitting devices that generate light energy from electrical energy by supplying voltage or current to the electrodes.

[0004] Examples of organic optoelectronic devices include organic photoelectric devices, organic light-emitting diodes, organic solar cells, and organic photosensitive drums.

[0005] Organic light-emitting diodes (OLEDs) have received considerable attention in recent years due to the increasing demand for flat panel display devices. OLEDs are devices that convert electrical energy into light, and their performance is greatly affected by the organic materials between the electrodes. Summary of the Invention

[0006] Technical issues

[0007] One implementation provides an organic optoelectronic device capable of achieving high efficiency and long lifetime characteristics.

[0008] Another embodiment provides a display device that includes an organic optoelectronic device.

[0009] Technical solution

[0010] According to one embodiment, an organic optoelectronic device is provided, comprising an anode and a cathode facing each other, a light-emitting layer between the anode and the cathode, a hole transport layer between the anode and the light-emitting layer, and a hole transport auxiliary layer between the light-emitting layer and the hole transport layer, wherein the light-emitting layer comprises a first compound represented by chemical formula 1 and a second compound represented by chemical formula 2, and the hole transport auxiliary layer comprises a third compound represented by chemical formula 2.

[0011] [Chemical Formula 1]

[0012] In chemical formula 1, Z 1 To Z 3 Each is independently N or CR a , Z 1 To Z 3 At least two of them are N. L 1 To L 3 Each is independently a single bond, a substituted or unsubstituted C6 to C20 arylene group, or a substituted or unsubstituted divalent C2 to C20 heterocyclic group. Ar 1 and Ar 2 One of them is a substituted or unsubstituted carbazoyl group, and Ar 1 and Ar 2 The other is a substituted or unsubstituted silyl group or a substituted or unsubstituted C6 to C30 aryl group. R 1 To R 8 and R a Each of these elements is independently hydrogen, deuterium, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heterocyclic, substituted or unsubstituted amino, substituted or unsubstituted silyl, cyano, or halogen. R 1 To R 8 They exist independently or two adjacent groups are linked together to form a ring. [Chemical Formula 2]

[0013] In chemical formula 2, L 4 and L 5 Each is an independent single bond or a substituted or unsubstituted C6 to C30 arylene. Ar 3 It is a substituted or unsubstituted C6 to C30 aryl group or a substituted or unsubstituted C2 to C30 heterocyclic group. R 17 To R 29 Each of these elements is independently hydrogen, deuterium, substituted or unsubstituted C1 to C30 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heterocyclic, substituted or unsubstituted amino, substituted or unsubstituted silyl, cyano, or halogen. m1 is an integer from 1 to 3, and When m1 is 2 or greater, R 21 They are the same as or different from each other.

[0014] According to another embodiment, a display device including an organic optoelectronic device is provided.

[0015] Beneficial effects

[0016] It can realize organic optoelectronic devices with high efficiency and long lifespan. Attached Figure Description

[0017] Figure 1 This is a schematic cross-sectional view of an organic optoelectronic device according to one embodiment.

[0018] <Explanation of Figure Markers>

[0019] 100: Organic Light Emitting Diode

[0020] 110: Anode

[0021] 120: Cathode

[0022] 130: Emissive layer

[0023] 140: Hole transport layer

[0024] 150: Hole transport auxiliary layer

[0025] 160: Electron transport layer Detailed Implementation

[0026] Embodiments of the present invention are described in detail below. However, these embodiments are exemplary, and this disclosure is not limited thereto.

[0027] In this specification, unless otherwise defined, “substituted” means that at least one hydrogen atom of a substituent or compound is replaced by a deuterium, halogen, hydroxyl, amino, substituted or unsubstituted C1 to C30 amino, nitro, substituted or unsubstituted C1 to C40 silyl, C1 to C30 alkyl, C1 to C10 alkylsilyl, C6 to C30 arylsilyl, C3 to C30 cycloalkyl, C3 to C30 heterocycloalkyl, C6 to C30 aryl, C2 to C30 heteroaryl, C1 to C20 alkoxy, C1 to C10 trifluoroalkyl, cyano, or combinations thereof.

[0028] In one embodiment of the invention, "substituted" means that at least one hydrogen atom of the substituent or compound is replaced by deuterium, C1 to C30 alkyl, C1 to C10 alkylsilyl, C6 to C30 arylsilyl, C3 to C30 cycloalkyl, C3 to C30 heterocycloalkyl, C6 to C30 aryl, C2 to C30 heteroaryl, or cyano. In a specific embodiment of the invention, "substituted" means that at least one hydrogen atom of the substituent or compound is replaced by deuterium, C1 to C20 alkyl, C3 to C20 cycloalkyl, C6 to C30 aryl, or cyano. In a specific embodiment of the invention, "substituted" means that at least one hydrogen atom of the substituent or compound is replaced by deuterium, C1 to C5 alkyl, C3 to C10 cycloalkyl, C6 to C18 aryl, or cyano. In a specific embodiment of the invention, "substituted" means that at least one hydrogen atom of the substituent or compound is replaced by deuterium, cyano, methyl, ethyl, propyl, butyl, tert-butyl, cyclopropyl, phenyl, biphenyl, terphenyl or naphthyl.

[0029] "Unsubstituted" means that the hydrogen atom is not replaced by another substituent and retains the hydrogen atom.

[0030] In this specification, "hydrogen (-H)" may include "deuterium-substituted (-D)" or "tritium-substituted (-T)".

[0031] In this specification, unless otherwise defined, “heterogeneous” means a functional group containing one to three heteroatoms selected from N, O, S, P and Si and the remaining carbon.

[0032] In this specification, "aryl" means a group comprising at least one aromatic hydrocarbon moiety, wherein all elements of the aromatic hydrocarbon moiety have conjugated p orbitals, such as phenyl, naphthyl, etc., and two or more aromatic hydrocarbon moiety may be linked by σ bonds and may be, for example, biphenyl, terphenyl, tetraphenyl, etc., and two or more aromatic hydrocarbon moiety may be directly or indirectly fused to provide a non-aromatic fused ring, such as fluorene.

[0033] Aryl groups can include monocyclic, polycyclic, or fused-ring polycyclic (i.e., rings that share adjacent carbon atom pairs) functional groups.

[0034] In this specification, "heterocyclic group" is a superordinate concept of a heteroaryl group and may include at least one heteroatom selected from N, O, S, P, and Si replacing carbon (C) in cyclic compounds such as aryl, cycloalkyl, their fused rings, or combinations thereof. When the heterocyclic group is fused, the entire ring or each ring of the heterocyclic group may include one or more heteroatoms.

[0035] As an example, "heteroaryl" can refer to an aryl group comprising at least one heteroatom selected from N, O, S, P, and Si. Two or more heteroaryl groups are directly linked by σ bonds, or when a heteroaryl group comprises two or more rings, the two or more rings can be fused. When a heteroaryl group is a fused ring, each ring may comprise one to three heteroatoms.

[0036] More specifically, the substituted or unsubstituted C6 to C30 aryl groups can be substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthraxyl, substituted or unsubstituted phenanthyl, substituted or unsubstituted naphthacenyl group, substituted or unsubstituted pyrene, substituted or unsubstituted biphenyl, substituted or unsubstituted p-terphenyl, substituted or unsubstituted meta-terphenyl, substituted or unsubstituted o-terphenyl, substituted or unsubstituted trefyl, substituted or unsubstituted triphenylene group, substituted or unsubstituted peryl, substituted or unsubstituted fluorenyl, substituted or unsubstituted indene, or combinations thereof, but are not limited thereto.

[0037] More specifically, the substituted or unsubstituted C2 to C30 heterocyclic group can be a substituted or unsubstituted furanyl group, a substituted or unsubstituted thiophene group, a substituted or unsubstituted pyrrole group, a substituted or unsubstituted pyrazolyl group, a substituted or unsubstituted imidazolyl group, a substituted or unsubstituted triazolyl group, a substituted or unsubstituted oxazolyl group, a substituted or unsubstituted thiazolyl group, a substituted or unsubstituted oxadiazolyl group, a substituted or unsubstituted thiadiazolyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted pyrimidinyl group, a substituted or unsubstituted pyrazinyl group, a substituted or unsubstituted triazinyl group, a substituted or unsubstituted benzofuranyl group, a substituted or unsubstituted benzothiopheneyl group, etc. The following are substituted or unsubstituted benzimidazolyl, substituted or unsubstituted indolyl, substituted or unsubstituted quinolinyl, substituted or unsubstituted isoquinolinyl, substituted or unsubstituted quinazolinyl, substituted or unsubstituted quinoxalinyl, substituted or unsubstituted naphridinyl, substituted or unsubstituted benzoxazinyl, substituted or unsubstituted benzothiazinyl, substituted or unsubstituted acridineyl, substituted or unsubstituted phenazinyl, substituted or unsubstituted phenothiazinyl, substituted or unsubstituted phenothiazinyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzofuranyl, or substituted or unsubstituted dibenzothiophenyl, or combinations thereof, but not limited thereto.

[0038] In this specification, hole characteristics refer to the ability to provide electrons to form holes when an electric field is applied, and due to the conductivity characteristics based on the highest occupied molecular orbital (HOMO) energy level, holes formed in the anode can be easily injected into the light-emitting layer and transported in the light-emitting layer.

[0039] Furthermore, electronic properties refer to the ability to accept electrons when an electric field is applied, and due to the conductivity of the lowest unoccupied molecular orbital (LUMO) energy level, electrons formed in the cathode can be easily injected into and transported in the light-emitting layer.

[0040] The following describes an organic optoelectronic device according to one embodiment.

[0041] Organic optoelectronic devices can be suitable devices that convert electrical energy into light energy and vice versa, such as organic photoelectric devices, organic light-emitting diodes, organic solar cells, or organic photosensitive drums.

[0042] This document describes an organic light-emitting diode as an example of an organic optoelectronic device, but the invention is not limited thereto, and it can be applied in the same manner to other organic optoelectronic devices.

[0043] In the accompanying drawings, the thicknesses of layers, films, panels, regions, etc., are enlarged for clarity. Throughout the specification, the same reference numerals denote the same elements. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it may be directly on the other element, or there may be intermediate elements present. Conversely, when an element is referred to as being "directly" on another element, there are no intermediate elements present.

[0044] Figure 1 This is a cross-sectional view showing an organic optoelectronic device according to one embodiment.

[0045] refer to Figure 1 An organic light-emitting diode 100 according to one embodiment includes an anode 110 and a cathode 120 facing each other, a light-emitting layer 130 between the anode 110 and the cathode 120, a hole transport layer 140 between the anode 110 and the light-emitting layer 130, and a hole transport auxiliary layer 150 between the light-emitting layer 130 and the hole transport layer 140, and also includes an electron transport layer 160.

[0046] The anode 110 may be made of a conductor with a high work function to facilitate hole injection, and may be, for example, a metal, a metal oxide, and / or a conductive polymer. The anode 10 may be made of: metals such as nickel, platinum, vanadium, chromium, copper, zinc, gold, or alloys thereof; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); combinations of metals and oxides such as ZnO and Al or SnO2 and Sb; conductive polymers such as, but not limited to, poly(3-methylthiophene), poly(3,4-(ethylene-1,2-dioxy)thiophene) (PEDOT), polypyrrole, and polyaniline.

[0047] Cathode 120 may be made of a conductor with a low work function to aid electron injection, and may be made of, for example, a metal, metal oxide, and / or a conductive polymer. Cathode 20 may include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, lead, cesium, barium, or alloys thereof; multilayer materials such as LiF / Al, LiO2 / Al, LiF / Ca, and BaF2 / Ca, but are not limited thereto.

[0048] The light-emitting layer 130 comprises at least two types of host and dopant, and may also comprise another organic compound as a mixed host. The host comprises a first compound, which is a bipolar compound with relatively strong electron transport properties; and a second compound, which is a compound with relatively strong hole transport properties.

[0049] In one embodiment, the light-emitting layer comprises a first compound represented by chemical formula 1 and a second compound represented by chemical formula 2.

[0050] [Chemical Formula 1]

[0051] In chemical formula 1, Z 1 To Z 3 Each is independently N or CR a , Z 1 To Z 3 At least two of them are N. L 1 To L 3 Each is independently a single bond, a substituted or unsubstituted C6 to C20 arylene group, or a substituted or unsubstituted divalent C2 to C20 heterocyclic group. Ar 1 and Ar 2 One of them is a substituted or unsubstituted carbazoyl group, and Ar 1 and Ar 2 The other is a substituted or unsubstituted silyl group or a substituted or unsubstituted C6 to C30 aryl group. R 1 To R 8 and R a Each of these elements is independently hydrogen, deuterium, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heterocyclic, substituted or unsubstituted amino, substituted or unsubstituted silyl, cyano, or halogen. R 1 To R 8They exist independently or two adjacent groups are linked together to form a ring. [Chemical Formula 2]

[0052] In chemical formula 2, L 4 and L 5 Each is an independent single bond or a substituted or unsubstituted C6 to C30 arylene. Ar 3 It is a substituted or unsubstituted C6 to C30 aryl group or a substituted or unsubstituted C2 to C30 heterocyclic group. R 17 To R 29 Each of these elements is independently hydrogen, deuterium, substituted or unsubstituted C1 to C30 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heterocyclic, substituted or unsubstituted amino, substituted or unsubstituted silyl, cyano, or halogen. m1 is an integer from 1 to 3, and When m1 is 2 or greater, R 21 They are the same as or different from each other.

[0053] By simultaneously including the first compound and the second compound, excellent interfacial properties can be exhibited, and compared with the case where the first compound or the second compound is used alone, the electron and hole balance in the active layer (e.g., light-emitting layer 130) of the organic optoelectronic device can be improved to enhance luminous efficiency by finely controlling the hole and electron mobility, and at the same time, lifetime can be improved by reducing unbound charge caused by the imbalance of electron and hole mobility.

[0054] Specifically, the organic optoelectronic device 100, which includes a first compound and a second compound as the main body, can be finely controlled to include a light-emitting layer 130 (to which the first compound and the second compound are applied), such that holes and electrons injected from the anode 110 and the cathode 120, respectively, have appropriate mobility in the light-emitting layer 130, thereby strongly inducing the generation of excitons in the light-emitting layer and improving the luminous efficiency in the light-emitting layer.

[0055] Furthermore, the difference in the mobility of holes and electrons injected from the anode 110 and cathode 120 within the light-emitting layer 130 can reduce or prevent the generation of excitons at inappropriate locations (such as at the interface between the light-emitting layer 130 and adjacent layers), and / or can reduce or prevent the accumulation of unbound charges at the interface between the light-emitting layer 130 and adjacent layers.

[0056] Therefore, the roll-off phenomenon, in which the luminous efficiency of the organic light-emitting diode 100 rapidly decreases due to non-emitting excitons and / or unbound charges, can be reduced or prevented, and thus the lifetime of the organic light-emitting diode 100 can ultimately be improved.

[0057] Furthermore, the aforementioned substrate exhibits excellent electrical matching with the blue-emitting dopant, which emits light in a blue emission spectrum and will be described subsequently, thereby improving the efficiency of organic optoelectronic devices and suppressing degradation. As an example, at least one of the first and second compounds possesses a high triplet energy level greater than or equal to about 2.8 eV, which facilitates exciton transfer to the blue-emitting dopant, thus enabling high-efficiency and long-lifetime organic optoelectronic devices.

[0058] As an example, in chemical formula 1, Z 1 To Z 3 Each can be N.

[0059] As an example, in chemical formula 1, Z 1 and Z 2 Each can be N, and Z can be... 3 It can be CR a .

[0060] As an example, in chemical formula 1, Z 1 and Z 3 Each can be N, and Z can be... 2 It can be CR a .

[0061] As an example, in chemical formula 1, Z 2 and Z 3 Each can be N, and Z can be... 1 It can be CR a .

[0062] As an example, in chemical formula 1, L 1 To L 3 Each of these can be a single bond, a substituted or unsubstituted phenylene, a substituted or unsubstituted biphenylene, a substituted or unsubstituted terphenylene, a substituted or unsubstituted naphthylene, a substituted or unsubstituted benzofuranylene, a substituted or unsubstituted dibenzofuranylene, a substituted or unsubstituted benzothiophene, a substituted or unsubstituted dibenzothiophene, a substituted or unsubstituted triphenylenylene group, or a substituted or unsubstituted fluorene.

[0063] As an example, in chemical formula 1, L 1 and L2 Each can be an independent single bond or a substituted or unsubstituted C6 to C20 arylene, and in Formula 1, L 3 It can be a single bond. As an example, in chemical formula 1, L 1 and L 2 Each can be independently a single bond or a substituted or unsubstituted phenylene, a substituted or unsubstituted biphenylene, a substituted or unsubstituted terphenylene, or a substituted or unsubstituted naphthylene, and in Formula 1, L 3 It can be a single key.

[0064] As an example, in chemical formula 1, Ar 1 It can be a substituted or unsubstituted C6 to C30 aryl group, and Ar 2 It can be a substituted or unsubstituted carbazole group. For example, Ar 1 It can be a substituted or unsubstituted phenyl, a substituted or unsubstituted biphenyl, a substituted or unsubstituted triphenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted anthraquinone, a substituted or unsubstituted phenanthryl, or a substituted or unsubstituted triphenylene.

[0065] As an example, when Ar in chemical formula 1 2 When the carbazolium group is substituted or unsubstituted, L 2 and L 3 They can be different from each other. For example, L 2 and L 3 One of them can be a single bond, and L 2 and L 3 The other one can be a substituted or unsubstituted C6 to C20 arylene, and can be, for example, a substituted or unsubstituted phenylene, a substituted or unsubstituted biphenylene, a substituted or unsubstituted terphenylene, or a substituted or unsubstituted naphthylene.

[0066] For example, R in chemical formula 1 a It can be hydrogen, deuterium, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted phenyl, or cyano.

[0067] The first compound can be represented by, for example, chemical formula 1a.

[0068] [Chemical Formula 1a]

[0069] In chemical formula 1a, Z 1 To Z 3 L 1 To L 3 and R 1 To R 8 Same as above, Ar 1 It can be a substituted or unsubstituted phenylsilyl group or a substituted or unsubstituted C6 to C30 aryl group, such as a substituted or unsubstituted triphenylsilyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted triphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracene group, a substituted or unsubstituted phenanthryl group, or a substituted or unsubstituted triphenylene group. R 9 To R 16 Each of these can be independently hydrogen, deuterium, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heterocyclic, substituted or unsubstituted amino, substituted or unsubstituted silyl, cyano, or halogen, and R 9 To R 16 They can exist independently or two adjacent groups can connect to each other to form a ring.

[0070] As an example, L in chemical formula 1a 2 and L 3 They can be different from each other, for example, L 2 It can be a substituted or unsubstituted phenylene, a substituted or unsubstituted biphenylene, a substituted or unsubstituted terphenylene, or a substituted or unsubstituted naphthylene, and L 3 It can be a single key.

[0071] As an example, at least one of the substituents in formulas 1 and 1a may be substituted with deuterium. The number of deuterium atoms substituted may be from 1 to the maximum number of hydrogen atoms in the formula, and may be, for example, from 1 to 40 or from 1 to 30, but is not limited thereto.

[0072] As an example, the second compound can be represented by any of the chemical formulas 2a to 2d.

[0073] [Chemical Formula 2a]

[0074] [Chemical Formula 2b]

[0075] [Chemical formula 2c]

[0076] [Chemical formula 2d]

[0077] In chemical formulas 2a to 2d, L 4 L 5 Ar 3 R17 To R 20 and R 22 To R 29 Same as above, R 21a R 21b and R 21c Each independently of the above R 21 The definitions are the same.

[0078] For example, L in chemical formulas 2 and 2a to 2d 4 It can be a single bond, a substituted or unsubstituted phenylene, a substituted or unsubstituted biphenylene, or a substituted or unsubstituted terphenylene.

[0079] For example, Ar in chemical formulas 2 and 2a to 2d 3 It can be a substituted or unsubstituted phenyl, a substituted or unsubstituted biphenyl, a substituted or unsubstituted triphenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted anthraquinone, a substituted or unsubstituted triphenylene, a substituted or unsubstituted carbazolyl, a substituted or unsubstituted benzothiophene, a substituted or unsubstituted dibenzothiophene, a substituted or unsubstituted benzofuran, a substituted or unsubstituted dibenzofuran, a substituted or unsubstituted benzothiophene, a substituted or unsubstituted dibenzothiophene, a substituted or unsubstituted fluorenyl, or a substituted or unsubstituted silyl.

[0080] For example, R in chemical formulas 2 and 2a to 2d 17 To R 29 R 21a R 21b and R 21c It can be hydrogen, deuterium, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted benzothiophene, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted benzofuran, substituted or unsubstituted dibenzofuran, substituted or unsubstituted benzothiophene, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted fluorenyl, substituted or unsubstituted silyl or cyano.

[0081] For example, Ar 3 R 17 To R 20 R 22 To R 29 R 21a R 21b and R 21c At least one of them can be a substituted or unsubstituted carbazolyl group.

[0082] As an example, at least one of the substituents in chemical formulas 2 and 2a to 2d may be substituted with deuterium. The number of deuterium atoms substituted may be from 1 to the maximum number of hydrogen atoms in the chemical formula, and may be, for example, from 1 to 40 or from 1 to 30, but is not limited thereto.

[0083] As an example, the first compound may include one or more compounds selected from those listed in Group 1, but is not limited thereto.

[0084] [Group 1]

[0085] (Dn is the number of hydrogen atoms replaced by deuterium, and indicates a structure in which one or more deuterium atoms are substituted.)

[0086] As an example, the second compound may include one or more compounds selected from those listed in Group 2, but is not limited thereto.

[0087] [Group 2]

[0088] [D-1] [D-2] [D-3] [D-4] [D-5]

[0089] [D-6] [D-7] [D-8] [D-9] [D-10]

[0090] [D-11] [D-12] [D-13] [D-14] [D-15]

[0091] [D-16] [D-17] [D-18] [D-19] [D-20]

[0092] [D-21] [D-22] [D-23] [D-24] [D-25]

[0093] [D-26] [D-27] [D-28] [D-29] [D-30]

[0094] [D-31] [D-32] [D-33] [D-34] [D-35]

[0095] [D-36] [D-37] [D-38] [D-39] [D-40]

[0096] [D-41] [D-42] [D-43] [D-44] [D-45]

[0097] [D-46] [D-47] [D-48] [D-49][D-50]

[0098] [D-51] [D-52] [D-53] [D-54] [D-55]

[0099] [D-56] [D-57] [D-58] [D-59] [D-60]

[0100] [D-61] [D-62] [D-63] [D-64] [D-65]

[0101] [D-66] [D-67] [D-68] [D-69] [D-70]

[0102] [D-71] [D-72] [D-73] [D-74] [D-75]

[0103] [D-76] [D-77] [D-78] [D-79] [D-80]

[0104] [D-81] [D-82] [D-83] [D-84] [D-85]

[0105] [D-86] [D-87] [D-88] [D-89] [D-90]

[0106] [D-91] [D-92] [D-93] [D-94] [D-95]

[0107] [D-96] [D-97] [D-98] [D-99] [D-100]

[0108] [D-101] [D-102] [D-103] [D-104] [D-105]

[0109] (Dn is the number of hydrogen atoms replaced by deuterium, and indicates a structure in which one or more deuterium atoms are substituted.)

[0110] The mixed body can include a first compound and a second compound in various ratios.

[0111] For example, the mixed body may include the first compound and the second compound in a weight ratio of about 10:90 to about 90:10, and within the range, the first compound and the second compound may be included in a weight ratio of about 20:80 to about 80:20, about 30:70 to about 70:30, about 40:60 to about 60:40 or about 50:50.

[0112] For example, the first compound may be included in an amount greater than or equal to that of the second compound; for instance, based on the total amount of the first and second compounds, the first compound may be included in an amount of 50 to 90 wt%.

[0113] For example, the first compound may be included in an amount less than or equal to that of the second compound; for instance, based on the total amount of the first and second compounds, the first compound may be included in an amount of 10 to 50 wt%.

[0114] In addition to the first and second compounds, the light-emitting layer 130 may also contain a light-emitting dopant.

[0115] A luminescent dopant is a material that is mixed in small amounts with a composition for use in organic optoelectronic devices to induce luminescence, and is typically a material such as a metal complex that emits light by being excited multiple times to a triplet or higher state. Luminescent dopants can be, for example, inorganic, organic, or organic / inorganic compounds, and one or more of these types can be used.

[0116] The luminescent dopant can be, for example, a phosphorescent photosensitive agent, a fluorescent dopant, or a combination thereof.

[0117] Phosphorus photosensitizers can be organometallic compounds and can efficiently transfer energy received from the host to the fluorescent dopant. Because the energy transferred to the fluorescent dopant increases and the excitons formed in the emissive layer emit light rapidly within the emissive layer, phosphorus photosensitizers can reduce the degradation of the light-emitting device.

[0118] The phosphorus photosensitizer can be, for example, an organometallic compound containing iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), rhodium (Rh), or combinations thereof, and can be, for example, an organometallic compound comprising an organic ligand comprising a nitrogen-containing ring. The nitrogen-containing ring can be, for example, substituted or unsubstituted pyridine, substituted or unsubstituted pyrimidine, substituted or unsubstituted triazine, substituted or unsubstituted carbazole, substituted or unsubstituted imidazole, substituted or unsubstituted benzimidazole, or combinations thereof, but is not limited thereto.

[0119] The phosphorus photosensitizer can be any of compounds P1 to P52, but is not limited thereto:

[0120] Fluorescent dopants can be, for example, polycyclic compounds, and can improve the luminous efficiency and lifetime characteristics of light-emitting diodes by receiving energy transfer within the emissive layer due to high absorption.

[0121] The fluorescent dopant can be a condensed polycyclic compound containing, for example, boron (B), nitrogen (N), or a combination thereof, and can be selected from, for example, compounds D1 to D30, but not limited thereto.

[0122]

[0123] Based on the total amount of the composition for organic optoelectronic devices, the phosphorescent photosensitizer and the fluorescent dopant may each be contained in an amount of less than or equal to about 20 wt%, and within the above range, the phosphorescent photosensitizer and the fluorescent dopant may be contained in amounts of about 0.1 to about 20 wt%, about 0.1 to about 15 wt%, about 0.1 to about 10 wt%, about 0.1 to about 7 wt%, about 0.1 to about 5 wt%, about 0.1 to about 4 wt%, about 1 to about 20 wt%, about 1 to about 15 wt%, about 1 to about 10 wt%, about 1 to about 7 wt%, about 1 to about 5 wt%, or about 1 to about 4 wt%.

[0124] For a description of the luminescent dopant, please refer to Korean Patent Publication Nos. 2023-0155972 and 2023-0155982.

[0125] The composition for organic optoelectronic devices may further include additives, etc., and the additives may be organic substances, inorganic substances, inorganic-organic substances, or combinations thereof.

[0126] Simultaneously, by combining the hybrid host and the luminescent dopant, the luminescent layer 130 can emit light in the blue emission spectrum. At least one of the first and second compounds described above has a high triplet energy level greater than or equal to about 2.8 eV, which facilitates exciton transfer to the blue luminescent dopant, thus enabling highly efficient and long-lived organic optoelectronic devices. The peak wavelength of the blue emission spectrum can be, for example, between about 410 nm and 480 nm, and within this range, between about 420 nm and 470 nm or between about 430 nm and 470 nm.

[0127] Hole transport layer 140 is located between anode 110 and light-emitting layer 130, and hole transport auxiliary layer 150 is located between light-emitting layer 130 and hole transport layer 140. Electron transport layer 160 is arranged between cathode 120 and light-emitting layer 130.

[0128] Hole transport layer 140 can facilitate hole transfer from anode 110 to light-emitting layer 130, and may contain, for example, an amine compound, but is not limited thereto. For example, the amine compound may have at least one aryl and / or heteroaryl group having hole-carrying properties. For example, the amine compound may be represented by chemical formula 6a or 6b, but is not limited thereto.

[0129] [Chemical Formula 6a] [Chemical Formula 6b]

[0130] In chemical formula 6a or 6b Ar a To Ar g Each of these elements independently consists of hydrogen, deuterium, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heteroaryl, or combinations thereof. Ar a To Ar c At least one of them and Ar d To Ar g At least one of them is a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C30 heteroaryl group, or a combination thereof, and Ar h It is a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted C2 to C30 heteroarylene group, or a combination thereof.

[0131] By being disposed between the hole transport layer 140 and the light-emitting layer 130 to contact the light-emitting layer 130, the hole transport auxiliary layer 150 can form an interface with the light-emitting layer 130.

[0132] The hole transport auxiliary layer 150 contains a third compound with bipolar properties having relatively strong hole characteristics.

[0133] As described above, the light-emitting layer 130 simultaneously contains a first compound with relatively strong electronic properties and a second compound with relatively strong hole properties, thereby increasing the mobility of electrons and holes compared to using them alone, and thus significantly improving the luminous efficiency.

[0134] In a device in which a material having biased electron characteristics or hole characteristics is introduced into the light-emitting layer, carrier recombination occurs at the interface between the light-emitting layer and the electron or charge transport layer, and relatively more excitons are formed. Therefore, due to the interaction between molecular excitons in the light-emitting layer and the charges at the interface of the hole transport layer, a roll-off phenomenon in which the efficiency decreases rapidly occurs, and the light-emitting lifetime characteristics also decrease rapidly.

[0135] To solve this problem, the first and second compounds are simultaneously introduced into the light-emitting layer so that the light-emitting region is not biased toward the electron transport layer or the hole transport layer, and in addition, by adding a hole transport auxiliary layer containing a third compound having relatively strong hole characteristics between the hole transport layer 140 and the light-emitting layer 130, the accumulation of unbound charges at the interface between the light-emitting layer 130 and the adjacent layer can be further reduced or prevented. Accordingly, it is possible to further reduce or prevent the roll-off phenomenon in which the light emission efficiency of the organic light-emitting diode 100 rapidly decreases due to non-luminous excitons and / or unbound charges, and thus the lifetime of the organic optoelectronic device 100 can be ultimately further improved.

[0136] The third compound may be represented by Chemical Formula 2.

[0137] Detailed information on Chemical Formula 2 is as described above, and the specific structure of the third compound is as described in Group 2.

[0138] In particular, when the HOMO energy level difference between the second compound and the third compound calculated by Formula 1 is less than or equal to 0.02 eV, the amount of charge accumulated between the interfaces can be reduced, so that improvements in the lifetime, driving voltage and / or efficiency of the organic light-emitting diode can be expected.

[0139] Formula 1 (HOMO energy level difference): {HOMO energy level of the second compound (DPV (differential pulse voltammetry) measurement value)} - {HOMO energy level of the third compound (DPV measurement value)}

[0140] <DPV: Differential Pulse Voltammetry Measurement Method>

[0141] Measuring instrument: Zive, SP2 (manufacturer, model name)

[0142] Measurement condition: energy level calculation

[0143] As shown below, the energy levels of the material were obtained by measuring the current change according to voltage using DPV (differential pulse voltammetry). A three-electrode cell consisting of a carbon electrode (working electrode), a Pt wire (counter electrode), Ag / AgCl (3 M NaCl) (reference electrode), and a DMF electrolyte in which 0.1 M tetrabutylammonium hexafluorophosphate (TBAF) was dissolved, with ferrocene dissolved in the electrolyte and used as a reference calibration value. 10 mg of sample was dissolved in 10 mL of electrolyte, and after purging with N2 gas, a voltage of +0.5 V to -2.2 V was applied to measure the reduction current value, followed by a voltage of +0.5 V to +1.8 V to measure the oxidation current value. (When each voltage was applied, it was applied with pulses provided in step voltage (V): 0.005 V, pulse height (V): 0.025 V, pulse width (s): 0.2 s, and period (s): 0.5 s). Then, the peak voltage values ​​under the reduction current and the peak voltage values ​​under the oxidation current are corrected using ferrocene to obtain LUMO and HOMO.

[0144] For example, the second and third compounds can be the same.

[0145] Furthermore, the electron transport layer 160 can further improve the electron injection and / or electron mobility between the cathode 120 and the light-emitting layer 130 and block holes.

[0146] The electron transport layer 160 may contain one or more compounds selected from, but is not limited to, the compounds listed in Group 3.

[0147] [Group 3]

[0148] Organic optoelectronic devices, including the aforementioned organic light-emitting diodes, can be applied to display devices.

[0149] Invention Model

[0150] In the following description, implementation methods are illustrated in more detail with reference to embodiments. However, these embodiments are exemplary, and the scope of the invention is not limited thereto.

[0151] In the following examples and synthesis examples, the starting materials and reactants used were purchased from Sigma-Aldrich Co. Ltd., TCI Inc., Tokyo Chemical Industry, or P & H Tech, or synthesized by known methods, unless otherwise specified.

[0152] Preparation of compounds for organic optoelectronic devices

[0153] The compounds presented as more specific examples of compounds of the present invention are synthesized through the following steps.

[0154] (Synthesis of the first compound)

[0155] Synthesis Example 1: Synthesis of Compound A-71

[0156] [Reaction Formula 1]

[0157] 11 g of (9,9'-(6-chloro-1,3,5-triazine-2,4-diyl)bis(9H-carbazole)), 12.5 g of (9-[2-(4,4,5,5-tetramethyl-1,3,2-dioxacyclopentaborane-2-yl)phenyl]-9H-carbazole), 12.5 g of (triphenyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxacyclopentaborane-2-yl)phenyl)silane), 1.43 g of Pd(PPh3)4 and 8.52 g of potassium carbonate were added to 62 ml of THF and 27 ml of distilled water, and the mixture was heated to reflux under a nitrogen atmosphere. After reacting for 18 hours, the mixture was cooled to room temperature, the organic layer was separated, and purified by column chromatography to obtain compound A-71 (15.27 g, 20.47 mmol, yield 83%).

[0158] LC / MS [M+H]+ 746.96.

[0159] (Synthesis of the second / third compound)

[0160] Synthesis Example 2: Synthesis of Compound D-57

[0161] [Reaction 2]

[0162] Compound D-57 was synthesized by referring to the method disclosed in Korean Patent Publication No. 10-2023-0155972.

[0163] Synthesis Example 3: Synthesis of Compound D-79

[0164] [Reaction 3]

[0165] Step 1: Synthesis of compound D-24

[0166] 25 g of 9-([1,1'-biphenyl]-3-yl)-2-bromo-9H-carbazole, 35.95 g of 3,9'-bicarbazole, 3.44 g of Pd2(dba)3, 8.67 g of sodium tert-butoxide, 5.5 ml (11.28 mmol) of a 50% solution of tri-tert-butylphosphine in toluene, and 250 ml of toluene were added, and the mixture was heated under reflux at nitrogen for 6 hours. The resulting mixture was extracted with water and dichloromethane and then purified by column chromatography to obtain 38.6 g (59.4 mmol) of compound D-24.

[0167] Step 2: Synthesis of compound D-79

[0168] Compound D-24, trifluoromethanesulfonic acid, and benzene-D6 were added and the mixture was stirred for 24 hours. Pure water was added, and the mixture was neutralized with a saturated K3PO4 solution. The organic layer was concentrated and purified by column chromatography to synthesize compound D-79.

[0169] Manufacturing of organic light-emitting diodes

[0170] Example 1

[0171] The glass substrate coated with an ITO (indium tin oxide) film was ultrasonically cleaned with distilled water. After washing with distilled water, the glass substrate was ultrasonically cleaned with solvents such as isopropanol, acetone, and methanol, and then dried. It was then transferred to a plasma cleaner and cleaned with oxygen plasma for 10 minutes before being transferred to a vacuum depositor. The prepared ITO transparent electrode was used as the anode. Compound A, doped with 3% NDP-9 (Novaled GmbH), was vacuum deposited on the ITO substrate to form a 100 Å thick hole injection layer. Compound A was then deposited on the hole injection layer to a thickness of 600 Å to form a hole transport layer. Compound D-57 obtained in Synthesis Example 2 was deposited on the hole transport layer to a thickness of 100 Å to form a hole transport auxiliary layer. On the hole transport auxiliary layer, compound A-71 obtained in Synthesis Example 1 and compound D-57 obtained in Synthesis Example 2 were used simultaneously as the host material, with 13 wt% P31 as a phosphorescent photosensitizer and 1.5 wt% D3 as a fluorescent dopant, to form a 400 Å thick emitting layer by vacuum deposition. Here, compound A-71 and compound D-57 were used in a weight ratio of 4:6. Subsequently, BCP was deposited on the emitting layer to a thickness of 50 Å to form an electron transport auxiliary layer, and compound B and LiQ were simultaneously vacuum deposited in a weight ratio of 1:1 to form a 300 Å thick electron transport layer. On the electron transport layer, 10 Å of LiQ and 1200 Å of Al were sequentially vacuum deposited to form a cathode, thereby fabricating an organic light-emitting diode.

[0172] It was fabricated to have the following structure: ITO / compound A (3% NDP-9 doped, 100 Å) / compound A (600 Å) / compound D-57 (100 Å) / EML [body (compound A-71 : compound D-57 = 34.2 wt% : 51.3 wt%) : P31 : D3 = 85.5 wt% : 13 wt% : 1.5 wt%] (400 Å) / BCP (50 Å) / compound B : LiQ (300 Å) / LiQ (10 Å) / Al (1200 Å).

[0173] Compound A: N-(9,9-diphenyl-9H-fluoren-2-yl)-N,9-diphenyl-9H-carbazole-2-amine

[0174] Compound B: 8-{4-[bis(naphthyl-2-yl)-1,3,5-triazin-2-yl]phenyl}quinoline

[0175] Example 2

[0176] Organic light-emitting diodes were manufactured in the same manner as in Example 1, except that compound D-79 obtained in Synthesis Example 3 was used instead of compound D-57 obtained in Synthesis Example 2 as the main body of the light-emitting layer to form the light-emitting layer and the hole transport auxiliary layer.

[0177] Comparative Example 1

[0178] Organic light-emitting diodes were fabricated in the same manner as in Example 1, except that mCP (1,3-bis(N-carbazolyl)benzene) was deposited to a thickness of 100 Å to form a hole transport auxiliary layer.

[0179] Comparative Example 2

[0180] The organic light-emitting diode was fabricated in the same manner as in Example 2, except that mCP was deposited to a thickness of 100 Å to form a hole transport auxiliary layer.

[0181] evaluate

[0182] The driving voltage and lifetime characteristics of the organic light-emitting diodes according to Examples 1 and 2 and Comparative Examples 1 and 2 were evaluated.

[0183] The specific measurement methods are as follows, and the results are shown in Tables 1 and 2.

[0184] (1) Measure the change in current density based on the voltage change

[0185] While increasing the voltage from 0 V to 10 V, the current flowing through the unit diode in the obtained organic light-emitting diode was measured using a current-voltmeter (Keithley 2400), and the measured current value was divided by the area to provide the result.

[0186] (2) Measure the change in brightness based on voltage changes

[0187] The brightness was measured using a luminance meter (MinoltaCs-1000A) while the voltage of the organic light-emitting diode was increased from 0 V to 10 V.

[0188] (3) Measure luminous efficiency

[0189] Using the brightness and current density and voltage measured according to (1) and (2) above, calculate the voltage at the same current density (10 mA / cm²). 2 Current efficiency (cd / A) at ).

[0190] (4) Measuring lifespan

[0191] In terms of brightness (cd / m 2 Maintain at 2000 cd / m 2The results were obtained by measuring the time it took for the current efficiency (cd / A) to drop to 95%.

[0192] The lifetime measurements of the organic light-emitting diodes according to Example 1 and Comparative Example 1 were calculated as relative values ​​based on Comparative Example 1 and are described in Table 1.

[0193] The lifetime measurements of the organic light-emitting diodes in Example 2 and Comparative Example 2 were calculated as relative values ​​based on Comparative Example 2 and are described in Table 2.

[0194] (5) Measure the driving voltage

[0195] Using a current-voltmeter (Keithley 2400), at 15 mA / cm 2 The drive voltage of each device was measured to obtain the results.

[0196] The driving voltages for Example 1 and Comparative Example 1 are calculated based on the relative values ​​of Comparative Example 1 and are described in Table 1.

[0197] The driving voltages for Example 2 and Comparative Example 2 are calculated based on the relative values ​​of Comparative Example 2 and are described in Table 2.

[0198] [Table 1]

[0199] [Table 2]

[0200] Referring to Tables 1 and 2, it can be confirmed that the organic light-emitting diodes according to the embodiments have improved driving voltage and lifetime characteristics compared with the organic light-emitting diodes according to the comparative examples.

[0201] Although the embodiments have been described in detail above, the scope of the invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts defined in the appended claims also fall within the scope of the invention.

Claims

1. An organic optoelectronic device, comprising: The anode and cathode facing each other, The light-emitting layer between the anode and the cathode, The hole transport layer between the anode and the light-emitting layer, and A hole transport auxiliary layer between the light-emitting layer and the hole transport layer, in, The light-emitting layer comprises a first compound represented by chemical formula 1 and a second compound represented by chemical formula 2. The hole transport auxiliary layer contains a third compound represented by chemical formula 2: [Chemical Formula 1] In chemical formula 1, Z 1 To Z 3 Each is independently N or CR a , Z 1 To Z 3 At least two of them are N. L 1 To L 3 Each is independently a single bond, a substituted or unsubstituted C6 to C20 arylene group, or a substituted or unsubstituted divalent C2 to C20 heterocyclic group. Ar 1 and Ar 2 One of them is a substituted or unsubstituted carbazoyl group, and Ar 1 and Ar 2 The other is a substituted or unsubstituted silyl group or a substituted or unsubstituted C6 to C30 aryl group. R 1 To R 8 and R a Each of these elements is independently hydrogen, deuterium, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heterocyclic, substituted or unsubstituted amino, substituted or unsubstituted silyl, cyano, or halogen. R 1 To R 8 They exist independently or two adjacent groups are linked together to form a ring. [Chemical Formula 2] In chemical formula 2, L 4 and L 5 Each is an independent single bond or a substituted or unsubstituted C6 to C30 arylene. Ar 3 It is a substituted or unsubstituted C6 to C30 aryl group or a substituted or unsubstituted C2 to C30 heterocyclic group. R 17 To R 29 Each of these elements is independently hydrogen, deuterium, substituted or unsubstituted C1 to C30 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heterocyclic, substituted or unsubstituted amino, substituted or unsubstituted silyl, cyano, or halogen. m1 is an integer from 1 to 3, and When m1 is 2 or greater, R 21 They are the same as or different from each other.

2. The organic optoelectronic device according to claim 1, wherein... L in chemical formula 1 1 and L 2 Each is independently a single bond or a substituted or unsubstituted C6 to C20 aryl group, and L in chemical formula 1 3 It is a single key.

3. The organic optoelectronic device according to claim 1, wherein... The first compound is represented by chemical formula 1a: [Chemical Formula 1a] In chemical formula 1a, Z 1 To Z 3 L 1 To L 3 and R 1 To R 8 Same as that defined in claim 1, Ar 1 It is a substituted or unsubstituted triphenylsilyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted triphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracene group, a substituted or unsubstituted phenanthryl group, or a substituted or unsubstituted triphenylene group. R 9 To R 16 Each of these elements is independently hydrogen, deuterium, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C2 to C30 heterocyclic, substituted or unsubstituted amino, substituted or unsubstituted silyl, cyano, or halogen. R 9 To R 16 They exist independently or two adjacent groups are linked together to form a ring.

4. The organic optoelectronic device according to claim 3, wherein... L in chemical formula 1a 2 It is a substituted or unsubstituted phenylene, a substituted or unsubstituted biphenylene, a substituted or unsubstituted terphenylene, or a substituted or unsubstituted naphthylene, and L in chemical formula 1a 3 It is a single key.

5. The organic optoelectronic device according to claim 1, wherein... Chemical formula 2 can be represented by any one of chemical formulas 2a to 2d: [Chemical Formula 2a] [Chemical Formula 2b] [Chemical formula 2c] [Chemical formula 2d] In chemical formulas 2a to 2d L 4 L 5 Ar 3 R 17 To R 20 and R 22 To R 29 Same as that defined in claim 1, and R 21a R 21b and R 21c Each independently of the R defined in claim 1 21 The definitions are the same.

6. The organic optoelectronic device according to claim 5, wherein... L 4 It is a single bond, a substituted or unsubstituted phenylene, a substituted or unsubstituted biphenylene, or a substituted or unsubstituted terphenylene. Ar 3 It is a substituted or unsubstituted phenyl, a substituted or unsubstituted biphenyl, a substituted or unsubstituted triphenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted anthraquinone, a substituted or unsubstituted triphenylene, a substituted or unsubstituted carbazolyl, a substituted or unsubstituted benzothiophene, a substituted or unsubstituted dibenzothiophene, a substituted or unsubstituted benzofuran, a substituted or unsubstituted dibenzofuran, a substituted or unsubstituted benzothiophene, a substituted or unsubstituted dibenzothiophene, or a substituted or unsubstituted fluorenyl.

7. The organic optoelectronic device according to claim 5, wherein... Ar 3 R 17 To R 20 R 22 To R 29 R 21a R 21b and R 21c At least one of them is a substituted or unsubstituted carbazoyl group.

8. The organic optoelectronic device according to claim 1, wherein... The HOMO energy level difference between the second and third compounds, calculated using Equation 1, is less than or equal to 0.02 eV. Equation 1 (HOMO energy level difference): {HOMO energy level of the second compound (DPV (differential pulse voltammetry) measurement)} - ​​{HOMO energy level of the third compound (DPV measurement)}.

9. The organic optoelectronic device according to claim 1, wherein... The second compound and the third compound are identical to each other.

10. The organic optoelectronic device according to claim 1, wherein... At least one of the first compound, the second compound, and the third compound is substituted with one or more deuterium compounds.

11. The organic optoelectronic device according to claim 1, wherein... The light-emitting layer also includes fluorescent dopants, phosphorescent sensitizers, or combinations thereof.

12. The organic optoelectronic device according to claim 11, wherein... The phosphorus photosensitizer is an organometallic compound, and the fluorescent dopant is a condensed polycyclic compound containing boron (B), nitrogen (N), or a combination thereof.

13. The organic optoelectronic device according to claim 1, wherein... The luminescent layer emits light in the blue emission spectrum.

14. A display device comprising the organic optoelectronic device according to any one of claims 1 to 13.

Images