Organic metal compound and organic light emitting diode including the same

Abstract

An organic metal compound represented by the following chemical formula 1 is disclosed. The organic metal compound is used as a dopant for the light-emitting layer of an organic light-emitting diode. Therefore, the operating voltage of the diode is reduced, and the light-emitting efficiency and life are improved: [Chemical Formula 1] Ir(L A ) m (L B ) n In chemical formula 1, L A represents a primary ligand and is one selected from the group consisting of Chemical Formula 2-1, Chemical Formula 2-2, and Chemical Formula 2-3, L B represents the auxiliary ligand represented by Chemical Formula 3, m and n each represent the number of ligands bound to Ir (iridium), m is 1, 2 or 3, n is 0, 1 or 2, and the sum of m and n is 3.

Description

Technical Field

[0001] The present disclosure relates to an organometallic compound, and more particularly, to an organometallic compound having phosphorescent properties and an organic light emitting diode including the organometallic compound. Background Art

[0002] As display devices are applied to various fields, interest in display devices is increasing. One type of display device is an organic light emitting display device including an organic light emitting diode (OLED), which is developing rapidly.

[0003] In an organic light emitting diode, when charges are injected into a light emitting layer formed between a positive electrode and a negative electrode, electrons and holes recombine with each other in the light emitting layer to form excitons, and thus the energy of the excitons is converted into light. As a result, the organic light emitting diode emits light. Compared with conventional display devices, an organic light emitting diode can operate at a low voltage, consume relatively less power, present excellent colors, and can be used in a variety of ways because a flexible substrate can be applied. In addition, the size of an organic light emitting diode can be freely adjusted. Summary of the invention

[0004] Compared with liquid crystal displays (LCDs), organic light emitting diodes (OLEDs) have excellent viewing angles and contrast ratios, and because OLEDs do not require backlights, they are lightweight and ultra-thin. Organic light emitting diodes include multiple organic layers between a negative electrode (electron injection electrode; cathode) and a positive electrode (hole injection electrode; anode). The multiple organic layers may include a hole injection layer, a hole transport layer, a hole transport auxiliary layer, an electron blocking layer, a light emitting layer, an electron transport layer, and the like.

[0005] In this organic light-emitting diode structure, when a voltage is applied between two electrodes, electrons and holes are injected into the light-emitting layer from the negative electrode and the positive electrode, respectively, thereby generating excitons in the light-emitting layer, which then drop to the ground state and emit light.

[0006] The organic materials used in organic light emitting diodes can be mainly divided into light emitting materials and charge transport materials. The light emitting material is an important factor in determining the luminous efficiency of organic light emitting diodes. The light emitting material must have high quantum efficiency, excellent electron and hole mobility, and must be uniformly and stably present in the light emitting layer. The light emitting material can be divided into light emitting materials that emit blue light, red light, and green light according to the color of light. The color generating material may include a host and a dopant to improve the color purity and luminous efficiency through energy transfer.

[0007] In recent years, there is a trend to use phosphorescent materials rather than fluorescent materials for the light-emitting layer. When a fluorescent material is used, singlet states, which are about 25% of the excitons generated in the light-emitting layer, are used for light emission, while triplet states, which are 75% of the excitons generated in the light-emitting layer, are mostly dissipated in the form of heat. However, when a phosphorescent material is used, both the singlet state and the triplet state are used for light emission.

[0008] Generally, organometallic compounds are used as phosphorescent materials used in organic light emitting diodes. There is a continuous need to research and develop phosphorescent materials to solve the problems of low efficiency and lifetime.

[0009] Therefore, an object of the present invention is to provide an organic metal compound capable of reducing an operating voltage and improving efficiency and lifespan, and an organic light emitting diode including an organic light emitting layer containing the organic metal compound.

[0010] The purpose of the present disclosure is not limited to the above-mentioned purpose. Other unmentioned purposes and advantages of the present disclosure can be understood by the following description and can be more clearly understood by the embodiments of the present disclosure. In addition, it is easy to understand that the purposes and advantages of the present disclosure can be achieved using the means shown in the claims and their combinations.

[0011] In order to achieve the above object, the present disclosure provides an organic metal compound having a novel structure represented by the following Chemical Formula 1 and an organic light emitting diode in which a light emitting layer comprises the organic metal compound as a dopant thereof:

[0012] [Chemical formula 1]Ir(L A ) m (L B ) n

[0013] In the chemical formula 1, L A represents a primary ligand and is one selected from the group consisting of the following Chemical Formula 2-1, Chemical Formula 2-2, and Chemical Formula 2-3,

[0014] L B represents an auxiliary ligand represented by the following chemical formula 3,

[0015] m and n each represent the number of ligands bound to Ir (iridium), m is 1, 2 or 3, n is 0, 1 or 2, and the sum of m and n is 3,

[0016] [Chemical formula 2-1]

[0017] [Chemical formula 2-2]

[0018] [Chemical formula 2-3]

[0019] [Chemical formula 3]

[0020] wherein in each of Chemical Formulae 2-1 to 2-3, X independently represents one selected from the group consisting of oxygen, sulfur, C(R)2, and NR,

[0021] R, R1, R 2-1 , R 2-2 , R 2-3 , R 3-1、 R 3-2 , R 3-3 , R 3-4 and R 3-5 each independently represents one selected from the group consisting of hydrogen, deuterium, halides, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl and phosphino,

[0022] In each of Chemical Formulae 2-1 to 2-3, R 2-1 , R 2-2 and R 2-3 Two adjacent functional groups in the ring may be combined with each other to form a ring structure, and R 3-1 , R 3-2 , R 3-3 , R 3-4 and R 3-5 Two adjacent functional groups in the ring can combine with each other to form a ring structure.

[0023] The auxiliary ligand represented by Chemical Formula 3 is a bidentate ligand, and the bidentate ligand is represented by the following Chemical Formula 4 or the following Chemical Formula 5:

[0024] [Chemical formula 4]

[0025] [Chemical formula 5]

[0026] In chemical formula 4, R 4-1 , R 4-2 , R 4-3 , R 4-4 , R 5-1 , R 5-2 , R 5-3 and R 5-4 Each independently represents one selected from the group consisting of hydrogen, deuterium, C1 to C5 straight chain alkyl, and C1 to C5 branched chain alkyl, wherein the C1 to C5 straight chain alkyl or the C1 to C5 branched chain alkyl may be substituted by at least one selected from deuterium and halogen elements,

[0027] R 4-1 , R 4-2 , R 4-3 and R 4-4 Two adjacent functional groups in the ring may be combined with each other to form a ring structure, and R 5-1 , R 5-2 , R 5-3 and R 5-4 Two adjacent functional groups in the ring can combine with each other to form a ring structure.

[0028] Wherein in Chemical Formula 5, R6, R7 and R8 each independently represent one selected from the group consisting of hydrogen, deuterium, C1 to C5 straight chain alkyl, and C1 to C5 branched chain alkyl, wherein the C1 to C5 straight chain alkyl or the C1 to C5 branched chain alkyl may be substituted by at least one selected from deuterium and halogen elements,

[0029] Two functional groups adjacent to each other among R6, R7 and R8 may be combined with each other to form a ring structure.

[0030] The organometallic compound according to the present disclosure may be used as a dopant of a light-emitting layer of an organic light-emitting diode, thereby reducing the operating voltage of the organic light-emitting diode and improving the efficiency and lifespan characteristics of the organic light-emitting diode.

[0031] The effects of the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a cross-sectional view schematically showing an organic light emitting diode in which a light emitting layer includes an organic metal compound according to an illustrative embodiment of the present disclosure.

[0033] Figure 2 is a cross-sectional view schematically illustrating an organic light emitting diode having a tandem structure having two light emitting stacks and including an organic metal compound represented by Chemical Formula 1 according to an illustrative embodiment of the present disclosure.

[0034] Figure 3 is a cross-sectional view schematically illustrating an organic light emitting diode having a tandem structure having two light emitting stacks and including an organic metal compound represented by Chemical Formula 1 according to an illustrative embodiment of the present disclosure.

[0035] Figure 4 is a cross-sectional view schematically illustrating an organic light emitting display device including an organic light emitting diode according to an illustrative embodiment of the present disclosure. DETAILED DESCRIPTION

[0036] The advantages and features of the present disclosure, and methods of achieving these advantages and features will become apparent by reference to the embodiments described in detail later in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, but may be implemented in various different forms. Therefore, these embodiments are set forth only to complete the present disclosure and to fully inform the scope of the present disclosure to those of ordinary skill in the art to which the present disclosure belongs, and the present disclosure is limited only by the scope of the claims.

[0037] The shapes, sizes, ratios, angles, quantities, etc. disclosed in the accompanying drawings for describing the embodiments of the present disclosure are illustrative, and the present disclosure is not limited thereto. The same reference numerals refer to the same elements here. In addition, in order to simplify the description, the description and details of well-known steps and elements are omitted. In addition, in the following detailed description of the present disclosure, many specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it should be understood that the present disclosure can be practiced without these specific details. In other cases, well-known methods, processes, components and circuits are not described in detail to avoid unnecessary obscurity of the various aspects of the present disclosure.

[0038] The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. As used herein, the singular "one" and "one" are also intended to include plural formations, unless the context clearly states otherwise. It should also be understood that when used in this specification, the terms "comprising", "comprising", "including" and "including" specify the presence of the features, integers, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, operations, elements, components and / or a part thereof. As used herein, the term "and / or" includes any combination and all combinations of one or more related listed items. When before the list of elements, expressions such as "at least one" can modify the entire list of elements, and may not modify the individual elements of the list. In the interpretation of numerical values, even if there is no clear description, errors or tolerances may also occur therein.

[0039] In addition, it should be understood that when a first element or layer is referred to as being present "on" a second element or layer, the first element may be directly disposed on the second element or may be indirectly disposed on the second element with a third element or layer disposed between the first and second elements or layers. It should be understood that when an element or layer is referred to as being "connected to" or "coupled to" another element or layer, it may be directly connected to or coupled to the other element or layer, or one or more intermediate elements or layers may be present. In addition, it should be understood that when an element or layer is referred to as being "between" two elements or layers, it may be the only element or layer between the two elements or layers, or one or more intermediate elements or layers may also be present.

[0040] In addition, as used herein, when a layer, film, region, plate, etc. is disposed "on" or "on top of" another layer, film, region, plate, etc., the former may directly contact the latter, or another layer, film, region, plate, etc. may be disposed between the former and the latter. As used herein, when a layer, film, region, plate, etc. is disposed directly "on" or "on top of" another layer, film, region, plate, etc., the former directly contacts the latter and no another layer, film, region, plate, etc. is disposed between the former and the latter. In addition, as used herein, when a layer, film, region, plate, etc. is disposed "below" or "beneath" another layer, film, region, plate, etc., the former may directly contact the latter, or another layer, film, region, plate, etc. may be disposed between the former and the latter. As used herein, when a layer, film, region, plate, etc. is disposed directly "below" or "beneath" another layer, film, region, plate, etc., the former directly contacts the latter and no another layer, film, region, plate, etc. is disposed between the former and the latter.

[0041] In the description of a temporal relationship, for example, a temporal precedence relationship between two events such as "after", "subsequently", "before", etc., unless "immediately after", "immediately followed", or "immediately before" is not specified, another event may occur between the two events.

[0042] It should be understood that although the terms "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the spirit and scope of the present disclosure, the first element, component, region, layer or part described below may be referred to as a second element, component, region, layer or part.

[0043] When interpreting numerical values, unless otherwise expressly stated, the values ​​are interpreted as including the error range.

[0044] It should be understood that when an element or layer is referred to as being “connected to” or “coupled to” another element or layer, it can be directly located, connected to or coupled to the other element or layer, or one or more intervening elements or layers may be present. In addition, it should be understood that when an element or layer is referred to as being “between” two elements or layers, it can be the only element or layer between the two elements or layers, or one or more intervening elements or layers may also be present.

[0045] The features of the various embodiments of the present disclosure may be combined with each other in part or in whole, and may be technically related to or interoperable with each other. The various embodiments may be implemented independently of each other, or may be implemented together in an associated relationship.

[0046] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as those commonly understood by those skilled in the art to which the inventive concept belongs. It should also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and will not be interpreted as an idealized or overly formal meaning unless explicitly defined herein.

[0047] The organometallic compound according to some embodiments of the present disclosure may be represented by the following Chemical Formula 1. When the organometallic compound is used as a dopant for a light-emitting layer of an organic light-emitting diode, the light-emitting efficiency and lifespan of the diode may be improved:

[0048] [Chemical formula 1]Ir(L A ) m (L B ) n

[0049] In the chemical formula 1, L A represents a primary ligand and is one selected from the group consisting of the following Chemical Formula 2-1, Chemical Formula 2-2, and Chemical Formula 2-3,

[0050] L B represents an auxiliary ligand represented by the following chemical formula 3,

[0051] m and n each represent the number of ligands bound to Ir (iridium), m is 1, 2 or 3, n is 0, 1 or 2, and the sum of m and n is 3,

[0052] [Chemical formula 2-1]

[0053] [Chemical formula 2-2]

[0054] [Chemical formula 2-3]

[0055] [Chemical formula 3]

[0056] wherein in each of Chemical Formulae 2-1 to 2-3, X independently represents one selected from the group consisting of oxygen, sulfur, C(R)2, and NR,

[0057] R, R1, R 2-1 , R 2-2 , R 2-3 , R3-1 , R 3-2 , R 3-3 , R 3-4 and R 3-5 each independently represents one selected from the group consisting of hydrogen, deuterium, halides, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl and phosphino,

[0058] In each of Chemical Formulae 2-1 to 2-3, R 2-1 , R 2-2 and R 2-3 Two adjacent functional groups in the ring may be combined with each other to form a ring structure, and R 3-1 , R 3-2 , R 3-3 , R 3-4 and R 3-5 Two adjacent functional groups in the ring can combine with each other to form a ring structure.

[0059] The auxiliary ligand represented by Chemical Formula 3 is a bidentate ligand, and the bidentate ligand is represented by the following Chemical Formula 4 or the following Chemical Formula 5:

[0060] [Chemical formula 4]

[0061] [Chemical formula 5]

[0062] In chemical formula 4, R 4-1 , R 4-2 , R 4-3 , R 4-4 , R 5-1 , R 5-2 , R 5-3 and R 5-4 Each independently represents one selected from the group consisting of hydrogen, deuterium, C1 to C5 straight chain alkyl, and C1 to C5 branched chain alkyl, wherein the C1 to C5 straight chain alkyl or the C1 to C5 branched chain alkyl may be substituted by at least one selected from deuterium and halogen elements,

[0063] R 4-1 , R 4-2 , R 4-3 and R 4-4 Two adjacent functional groups in the ring may be combined with each other to form a ring structure, and R 5-1 , R 5-2 , R 5-3 and R 5-4 Two adjacent functional groups in the ring can combine with each other to form a ring structure.

[0064] Wherein in Chemical Formula 5, R6, R7 and R8 each independently represent one selected from the group consisting of hydrogen, deuterium, C1 to C5 straight chain alkyl, and C1 to C5 branched chain alkyl, wherein the C1 to C5 straight chain alkyl or the C1 to C5 branched chain alkyl may be substituted by at least one selected from deuterium and halogen elements,

[0065] Two functional groups adjacent to each other among R6, R7 and R8 may be combined with each other to form a ring structure.

[0066] As described above, the auxiliary ligand bonded to iridium (Ir) as the central coordination metal may be a bidentate ligand. The bidentate ligand may contain an electron donor, thereby increasing the amount of MLCT (metal to ligand charge transfer), so that the organic light emitting diode exhibits improved light emitting characteristics, such as high luminous efficiency and high external quantum efficiency.

[0067] The organometallic compound according to an embodiment of the present disclosure may have a heteroleptic or homoleptic structure. Specifically, the organometallic compound according to an embodiment of the present disclosure may have a heteroleptic structure, wherein in Chemical Formula 1, m is 1 and n is 2; or a heteroleptic structure wherein m is 2 and n is 1; or a homoleptic structure wherein m is 3 and n is 0.

[0068] Specific examples of the compound represented by Chemical Formula 1 of the present disclosure may include one selected from the group consisting of the following compounds 1 to 370. However, the specific examples of the compound represented by Chemical Formula 1 of the present disclosure are not limited thereto as long as they satisfy the definition of the above Chemical Formula 1:

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082] According to one embodiment of the present disclosure, the organometallic compound represented by Chemical Formula 1 of the present disclosure may be used as a red phosphorescent material or a green phosphorescent material, preferably, as a green phosphorescent material.

[0083] Reference Figure 1 According to one embodiment of the present disclosure, an organic light emitting diode 100 may be provided, which includes: a first electrode 110; a second electrode 120 facing the first electrode 110; and an organic layer 130 disposed between the first electrode 110 and the second electrode 120. The organic layer 130 may include a light emitting layer 160, and the light emitting layer 160 may include a host material 160' and a dopant 160". The dopant 160" may be made of an organic metal compound represented by Chemical Formula 1. In addition, in the organic light emitting diode 100, the organic layer 130 disposed between the first electrode 110 and the second electrode 120 may be formed by sequentially stacking a hole injection layer 140 (HIL), a hole transport layer 150 (HTL), a light emitting layer 160 (EML), an electron transport layer 170 (ETL), and an electron injection layer 180 (EIL) on the first electrode 110. The second electrode 120 may be formed on the electron injection layer 180, and a protective layer (not shown) may be formed on the second electrode 120.

[0084] In addition, despite the Figure 1 Not shown, a hole transport auxiliary layer may be further added between the hole transport layer 150 and the light emitting layer 160. The hole transport auxiliary layer may contain a compound having good hole transport properties, and the difference between the HOMO energy levels of the hole transport layer 150 and the light emitting layer 160 may be reduced so as to adjust the hole injection characteristics. Therefore, the hole accumulation at the interface between the hole transport auxiliary layer and the light emitting layer 160 may be reduced, thereby reducing the quenching phenomenon in which the exciton disappears at the interface due to the polaron. Therefore, the degradation of the element may be reduced and the element may be stabilized, thereby improving its efficiency and lifespan.

[0085] The first electrode 110 may serve as a positive electrode, and may be made of ITO, IZO, tin oxide, or zinc oxide, which is a conductive material having a relatively large work function value. However, the present disclosure is not limited thereto.

[0086] The second electrode 120 may function as a negative electrode, and may include Al, Mg, Ca, or Ag, or an alloy or combination thereof, which is a conductive material having a relatively small work function value. However, the present disclosure is not limited thereto.

[0087] The hole injection layer 140 may be located between the first electrode 110 and the hole transport layer 150. The hole injection layer 140 may have a function of improving the interface characteristics between the first electrode 110 and the hole transport layer 150, and may be selected from a material having appropriate conductivity. The hole injection layer 140 may include one or more selected from the group consisting of MTDATA, CuPc, TCTA, HATCN, TDAPB, PEDOT / PSS, and N1,N1'-([1,1'-biphenyl]-4,4'-diyl)bis(N1,N4,N4)-triphenylbenzene-1,4-diamine). Preferably, the hole injection layer 140 may include N1,N1'-([1,1'-biphenyl]-4,4'-diyl)bis(N1,N4,N4-triphenylbenzene-1,4-diamine). However, the present disclosure is not limited thereto.

[0088] The hole transport layer 150 may be located near the light emitting layer and between the first electrode 110 and the light emitting layer 160. The material of the hole transport layer 150 may include a compound selected from the group consisting of TPD, NPB, CBP, N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazole-3-yl)phenyl)-9H-fluorene-2-amine, N-(biphenyl-4-yl)-N-(4-(9-phenyl-9H-carbazole-3-yl)phenyl)biphenyl)-4-amine, etc. Preferably, the material of the hole transport layer 150 may include NPB. However, the present disclosure is not limited thereto.

[0089] According to the present disclosure, the light-emitting layer 160 may include a host material 160' and an organic metal compound represented by Chemical Formula 1 as a dopant 160" doped into the host to improve the light-emitting efficiency of the host and the organic light-emitting diode. The light-emitting layer 160 may be formed by adding about 1 wt% to 30 wt% of the organic metal compound of Chemical Formula 1 of the present disclosure, i.e., the dopant 160", to the host material 160', and may emit green or red light. More preferably, the organic metal compound of Chemical Formula 1 of the present disclosure may act as a green phosphorescent material.

[0090] In the light emitting layer 160 of the present disclosure, the organic metal compound represented by Chemical Formula 1 may be used as the dopant 160 ″, and the compound containing a carbazole group may be used as the host material 160 ′. For example, the host material containing a carbazole group may be one or more compounds selected from the compounds having structures shown in Table 1 below. However, the present disclosure is not limited thereto.

[0091] Table 1

[0092]

[0093]

[0094] In addition, the electron transport layer 170 and the electron injection layer 180 may be sequentially stacked between the light emitting layer 160 and the second electrode 120. The material of the electron transport layer 170 requires high electron mobility so that electrons can be stably supplied to the light emitting layer under smooth electron transport.

[0095] For example, the material of the electron transport layer 170 may include a compound selected from the group consisting of: Alq3 (tris(8-hydroxyquinoline)aluminum), Liq (8-hydroxyquinoline lithium), PBD (2-(4-biphenyl))-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), TAZ (3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole), spiro-PBD, BAlq (bis(2-methyl-8-quinolinate)-4-(phenylphenol)aluminum), SAlq, TPBi (2,2',2-(1,3,5-benzenetriyl)-tri(1-phenyl-1-H-benzimidazole), oxadiazole, triazole, phenanthroline, benzoxazole, benzothiazole, and 2-(4-(9,10-di(naphthalene-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole. Preferably, the material of the electron transport layer 170 may include 2-(4-(9,10-di(naphthalene-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole. However, the present disclosure is not limited thereto.

[0096] The electron injection layer 180 is used to promote electron injection, and the material of the electron injection layer may include a compound selected from the group consisting of Alq3 (tris (8-hydroxyquinoline) aluminum), PBD, TAZ, spiro-PBD, BAlq, SAlq, etc. However, the present disclosure is not limited to this. Alternatively, the electron injection layer 180 may be made of a metal compound. The metal compound may include, for example, one or more selected from the group consisting of Liq, LiF, NaF, KF, RbF, CsF, FrF, BeF2, MgF2, CaF2, SrF2, BaF2 and RaF2. However, the present disclosure is not limited to this.

[0097] The organic light emitting diode according to the present disclosure may be implemented as a white light emitting diode having a series structure. The series organic light emitting diode according to the illustrative embodiment of the present disclosure may be formed into a structure in which adjacent light emitting stacks in two or more light emitting stacks are connected to each other via a charge generation layer (CGL). The organic light emitting diode may include at least two light emitting stacks arranged on a substrate, wherein each of the at least two light emitting stacks includes a first electrode and a second electrode facing each other, and a light emitting layer arranged between the first electrode and the second electrode to emit light of a specific wavelength band. In this case, the light emitting layer included in at least one light emitting stack in the plurality of light emitting stacks may include an organic metal compound represented by Chemical Formula 1 according to the present disclosure as a dopant. Adjacent light emitting stacks in the plurality of light emitting stacks in the series structure may be connected to each other via a charge generation layer CGL including an N-type charge generation layer and a P-type charge generation layer.

[0098] Figure 2 and Figure 3 are cross-sectional views schematically illustrating organic light emitting diodes in a tandem structure having two light emitting stacks and an organic light emitting diode in a tandem structure having three light emitting stacks, respectively, according to some embodiments of the present disclosure.

[0099] like Figure 2 As shown, the organic light emitting diode 100 according to the present disclosure includes a first electrode 110 and a second electrode 120 facing each other, and an organic layer 230 located between the first electrode 110 and the second electrode 120. The organic layer 230 may be located between the first electrode 110 and the second electrode 120 and may include a first light emitting stack ST1 including a first light emitting layer 261, a second light emitting stack ST2 located between the first light emitting stack ST1 and the second electrode 120 and including a second light emitting layer 262, and a charge generation layer CGL located between the first light emitting stack ST1 and the second light emitting stack ST2. The charge generation layer CGL may include an N-type charge generation layer 291 and a P-type charge generation layer 292. At least one of the first light emitting layer 261 and the second light emitting layer 262 may include the organic metal compound represented by Chemical Formula 1 according to the present disclosure as a dopant. For example, as Figure 2 As shown, the second light emitting layer 262 of the second light emitting stack ST2 may include a host material 262', and a dopant 262" made of an organic metal compound represented by Chemical Formula 1 doped therein.

[0100] like Figure 3As shown, the organic light emitting diode 100 according to the present disclosure includes a first electrode 110 and a second electrode 120 facing each other, and an organic layer 330 located between the first electrode 110 and the second electrode 120. The organic layer 330 may be located between the first electrode 110 and the second electrode 120 and may include a first light emitting stack ST1 including a first light emitting layer 261, a second light emitting stack ST2 including a second light emitting layer 262, a third light emitting stack ST3 including a third light emitting layer 263, a first charge generation layer CGL1 located between the first light emitting stack ST1 and the second light emitting stack ST2, and a second charge generation layer CGL2 located between the second light emitting stack ST2 and the third light emitting stack ST3. The first charge generation layer CGL1 may include an N-type charge generation layer 291 and a P-type charge generation layer 292. The second charge generation layer CGL2 may include an N-type charge generation layer 293 and a P-type charge generation layer 294. At least one of the first light emitting layer 261, the second light emitting layer 262, and the third light emitting layer 263 may include the organic metal compound represented by Chemical Formula 1 according to the present disclosure as a dopant. Figure 3 As shown, the second light emitting layer 262 of the second light emitting stack ST2 may include a host material 262', and a dopant 262" made of an organic metal compound represented by Chemical Formula 1 doped therein.

[0101] In addition, the organic light emitting diode according to an embodiment of the present disclosure may include a tandem structure in which four or more light emitting stacks and three or more charge generation layers are disposed between the first electrode and the second electrode.

[0102] The organic light emitting diode according to the present disclosure can be used as a light emitting element of each of an organic light emitting display device and a lighting device. In one embodiment, Figure 4 is a cross-sectional view schematically illustrating an organic light emitting display device including an organic light emitting diode according to some embodiments of the present disclosure as a light emitting element thereof.

[0103] like Figure 4 As shown, the organic light emitting display device 3000 includes a substrate 3010, an organic light emitting diode 4000, and a packaging film 3900 covering the organic light emitting diode 4000. A driving thin film transistor Td as a driving element and the organic light emitting diode 4000 connected to the driving thin film transistor Td are located on the substrate 3010.

[0104] Despite Figure 4Not explicitly shown, gate lines and data lines that cross each other to define pixel areas, power lines that extend parallel to and are spaced apart from one of the gate lines and the data lines, switching thin film transistors connected to the gate lines and the data lines, and storage capacitors connected to one electrode of the thin film transistor and the power line are further formed on the substrate 3010.

[0105] The driving thin film transistor Td is connected to the switching thin film transistor, and includes a semiconductor layer 3100 , a gate electrode 3300 , a source electrode 3520 , and a drain electrode 3540 .

[0106] The semiconductor layer 3100 may be formed on the substrate 3010 and may be made of an oxide semiconductor material or polysilicon. When the semiconductor layer 3100 is made of an oxide semiconductor material, a light shielding pattern (not shown) may be formed below the semiconductor layer 3100. The light shielding pattern prevents light from entering the semiconductor layer 3100 to prevent the semiconductor layer 3010 from being degraded by light. Alternatively, the semiconductor layer 3100 may be made of polysilicon. In this case, both edges of the semiconductor layer 3100 may be doped with impurities.

[0107] A gate insulating layer 3200 made of an insulating material is formed on the entire surface of the substrate 3010 and on the semiconductor layer 3100. The gate insulating layer 3200 may be made of an inorganic insulating material such as silicon oxide or silicon nitride.

[0108] The gate electrode 3300 made of a conductive material such as metal is formed on the gate insulating layer 3200 and corresponds to the center of the semiconductor layer 3100. The gate electrode 3300 is connected to the switching thin film transistor.

[0109] An interlayer insulating layer 3400 made of an insulating material is formed on the entire surface of the substrate 3010 and on the gate 3300. The interlayer insulating layer 3400 may be made of an inorganic insulating material such as silicon oxide or silicon nitride, or an organic insulating material such as benzocyclobutene or photo acryl.

[0110] The interlayer insulating layer 3400 has first and second semiconductor layer contact holes 3420 and 3440 defined therein to respectively expose opposite sides of the semiconductor layer 3100. The first and second semiconductor layer contact holes 3420 and 3440 are respectively located on opposite sides of the gate 3300 and spaced apart from the gate 3300.

[0111] A source electrode 3520 and a drain electrode 3540 made of a conductive material such as metal are formed on the interlayer insulating layer 3400. The source electrode 3520 and the drain electrode 3540 are located around the gate electrode 3300 and are spaced apart from each other, and each contacts opposite sides of the semiconductor layer 3100 through the first semiconductor layer contact hole 3420 and the second semiconductor layer contact hole 3440, respectively. The source electrode 3520 is connected to a power supply line (not shown).

[0112] The semiconductor layer 3100 , the gate electrode 3300 , the source electrode 3520 , and the drain electrode 3540 constitute a driving thin film transistor Td. The driving thin film transistor Td has a coplanar structure in which the gate electrode 3300 , the source electrode 3520 , and the drain electrode 3540 are located on top of the semiconductor layer 3100 .

[0113] Alternatively, the driving thin film transistor Td may have an inverse staggered structure, in which the gate is disposed below the semiconductor layer, and the source and drain are disposed above the semiconductor layer. In this case, the semiconductor layer may be made of amorphous silicon. In one example, the switching thin film transistor (not shown) may have substantially the same structure as the driving thin film transistor (Td).

[0114] In one example, the organic light emitting display device 3000 may include a color filter 3600 that absorbs light generated from an electroluminescent element (light emitting diode) 4000. For example, the color filter 3600 may absorb red (R), green (G), blue (B), and white (W) light. In this case, red, green, and blue color filter patterns that absorb light may be formed in different pixel regions, respectively. Each of these color filter patterns may be arranged to overlap with each organic layer 4300 of the organic light emitting diode 4000 to emit light corresponding to the wavelength band of each color filter. The use of the color filter 3600 may enable the organic light emitting display device 3000 to achieve full color.

[0115] For example, when the organic light emitting display device 3000 is a bottom emission type, the color filter 3600 that absorbs light may be disposed on a portion of the interlayer insulating layer 3400 corresponding to the organic light emitting diode 4000. In an alternative embodiment, when the organic light emitting display device 3000 is a top emission type, the color filter may be disposed on the top of the organic light emitting diode 4000, that is, on the top of the second electrode 4200. For example, the color filter 3600 may be formed to have a thickness of 2-5 μm.

[0116] In one example, a protective layer 3700 is formed to cover the driving thin film transistor Td, and has a drain contact hole 3720 defined therein that exposes the drain electrode 3540 of the driving thin film transistor Td.

[0117] On the protective layer 3700 , each first electrode 4100 connected to the drain electrode 3540 of the driving thin film transistor Td via the drain contact hole 3720 is respectively formed in each pixel region.

[0118] The first electrode 4100 may be used as a positive electrode (anode) and may be made of a conductive material having a relatively large work function value. For example, the first electrode 4100 may be made of a transparent conductive material such as ITO, IZO, or ZnO.

[0119] In one example, when the organic light-emitting display device 3000 is a top emission type, a reflective electrode or a reflective layer may be further formed under the first electrode 4100. For example, the reflective electrode or the reflective layer may be made of one of aluminum (Al), silver (Ag), nickel (Ni), and aluminum-palladium-copper (APC) alloy.

[0120] A bank layer 3800 covering the edge of the first electrode 4100 is formed on the protective layer 3700. The bank layer 3800 exposes the center of the first electrode 4100 corresponding to the pixel area.

[0121] The organic layer 4300 is formed on the first electrode 4100. As required, the organic light emitting diode 4000 may have a series structure. Figures 2 to 4 , which shows some embodiments of the present disclosure and its above description.

[0122] The second electrode 4200 is formed on the substrate 3010 on which the organic layer 4300 has been formed. The second electrode 4200 is provided on the entire surface of the display region and is made of a conductive material having a relatively small work function value, and the second electrode 4200 may be used as a negative electrode (cathode). For example, the second electrode 4200 may be made of one of aluminum (Al), magnesium (Mg), and an aluminum-magnesium alloy (Al-Mg).

[0123] The first electrode 4100 , the organic layer 4300 , and the second electrode 4200 constitute an organic light emitting diode 4000 .

[0124] The encapsulation film 3900 is formed on the second electrode 4200 to prevent external moisture from penetrating into the organic light emitting diode 4000. Figure 4 Although not explicitly shown in FIG. 3 , the encapsulation film 3900 may have a three-layer structure in which a first inorganic layer, an organic layer, and an inorganic layer are sequentially stacked. However, the present disclosure is not limited thereto.

[0125] Hereinafter, the synthesis example and the present embodiment of the present disclosure will be described. However, the following present embodiment is only an example of the present disclosure. The present disclosure is not limited thereto.

[0126] Synthesis Example - Preparation of Ligand Intermediate

[0127] <Preparation of Ligand A-1>

[0128]

[0129] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-1 (10.40 g, 0.05 mol) was dissolved in 250 mL THF, and then iodomethane (42.58 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound A-1 (18.13 g, 92%).

[0130] <Preparation of Ligand B-1>

[0131]

[0132] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-1 (10.40 g, 0.05 mol) was dissolved in 250 mL THF, and then 2-iodopropane (51.00 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound B-1 (19.00 g, 90%).

[0133] <Preparation of Ligand C-1>

[0134]

[0135] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-1 (10.40 g, 0.05 mol) was dissolved in 250 mL THF, and then 1-iodobutane (55.21 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound C-1 (18.53 g, 85%).

[0136] <Preparation of Ligand D-1>

[0137]

[0138] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-2 (12.90 g, 0.05 mol) was dissolved in 250 mL THF, and then iodomethane (42.58 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound D-1 (19.10 g, 86%).

[0139] <Preparation of Ligand E-1>

[0140]

[0141] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-2 (12.90 g, 0.05 mol) was dissolved in 250 mL THF, and then 2-iodopropane (51.00 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound E-1 (21.00 g, 89%).

[0142] <Preparation of Ligand F-1>

[0143]

[0144] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-2 (12.90 g, 0.05 mol) was dissolved in 250 mL of THF, and then 1-iodobutane (55.21 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound F-1 (22.85 g, 94%).

[0145] <Preparation of Ligand G-1>

[0146]

[0147] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-3 (12.90 g, 0.05 mol) was dissolved in 250 mL THF, and then iodomethane (42.58 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound G-1 (20.43 g, 92%).

[0148] <Preparation of Ligand H-1>

[0149]

[0150] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-3 (12.90 g, 0.05 mol) was dissolved in 250 mL THF, and then 2-iodopropane (51.00 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound H-1 (21.00 g, 89%).

[0151] <Preparation of Ligand I-1>

[0152]

[0153] In a 500 mL round-bottom flask and under a nitrogen atmosphere, SM-3 (12.90 g, 0.05 mol) was dissolved in 250 mL THF, and then 1-iodobutane (55.21 g, 0.30 mol) was sequentially added to the reaction solution, and then the reaction solution was stirred at 40° C. for 24 hours. When the reaction was completed, the reaction solution was filtered and concentrated under reduced pressure to obtain compound I-1 (21.15 g, 87%).

[0154] Synthesis Example - Preparation of Ligand

[0155] <Preparation of Ligand A>

[0156]

[0157] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant A-1 (19.70 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL of acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. When the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound A (20.74 g, 91%), and was used for the next step without further purification.

[0158] <Preparation of Ligand B>

[0159]

[0160] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant B-1 (21.10 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. After the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound B (21.78 g, 90%), and was used for the next step without further purification.

[0161] <Preparation of Ligand C>

[0162]

[0163] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant C-1 (21.81 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. When the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound C (23.15 g, 93%), and was used for the next step without further purification.

[0164] <Preparation of Ligand D>

[0165]

[0166] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant D-1 (22.20 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. When the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound D (24.03 g, 95%), and was used for the next step without further purification.

[0167] <Preparation of Ligand E>

[0168]

[0169] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant E-1 (23.61 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL of acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. When the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound E (22.70 g, 85%), and was used for the next step without further purification.

[0170] <Preparation of Ligand F>

[0171]

[0172] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant F-1 (24.31 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. After the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound F (25.75 g, 94%), and was used for the next step without further purification.

[0173] <Preparation of Ligand G>

[0174]

[0175] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant G-1 (22.20 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL of acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. When the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound G (22.51 g, 89%), and was used for the next step without further purification.

[0176] <Preparation of Ligand H>

[0177]

[0178] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant H-1 (23.61 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL of acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. When the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound H (24.83 g, 93%), and was used for the next step without further purification.

[0179] <Preparation of Ligand I>

[0180]

[0181] In a 500 mL round-bottom flask and under a nitrogen atmosphere, reactant I-1 (24.31 g, 0.05 mol) and silver oxide (5.80 g, 0.025 mol) were dissolved in 250 mL acetonitrile, and the reaction solution was stirred at room temperature for 24 hours. After the reaction was completed, the reaction solution was concentrated under reduced pressure to obtain compound I (25.75 g, 94%), and was used for the next step without further purification.

[0182] Synthesis Example - Preparation of Iridium Compounds

[0183] <Preparation of Iridium Compound 1>

[0184]

[0185] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand A (1.37g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and moisture was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The crude product obtained was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 1 (1.56g, 72%).

[0186] <Preparation of Iridium Compound 2>

[0187]

[0188] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand B (1.45g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 2 (1.53g, 68%).

[0189] <Preparation of Iridium Compound 3>

[0190]

[0191] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand C (1.50g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The crude product obtained was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 3 (1.79g, 78%).

[0192] <Preparation of Iridium Compound 46>

[0193]

[0194] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand D (1.52g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 46 (1.76g, 76%).

[0195] <Preparation of Iridium Compound 47>

[0196]

[0197] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand E (1.60g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 47 (1.80g, 75%).

[0198] <Preparation of Iridium Compound 48>

[0199]

[0200] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand F (1.64g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The crude product obtained was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 48 (1.78g, 73%).

[0201] <Preparation of Iridium Compound 61>

[0202]

[0203] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand G (1.51g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The crude product obtained was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 61 (1.62g, 70%).

[0204] <Preparation of Iridium Compound 62>

[0205]

[0206] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand H (1.60g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 62 (1.92g, 80%).

[0207] <Preparation of Iridium Compound 63>

[0208]

[0209] In a 150mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M1 (1.61g, 1.5mmol) and ligand I (1.64g, 3mmol) were dissolved in o-xylene (150mL) and the reaction solution was stirred under reflux for 18 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of ethyl acetate: hexane = 25: 75 to obtain the above-mentioned iridium compound 63 (2.00g, 82%).

[0210] <Preparation of Iridium Compound 331>

[0211]

[0212] In a 250mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M2 (2.01g, 1.5mmol) and ligand L1 (0.47g, 3mmol) were dissolved in toluene (100mL) and the reaction solution was stirred under reflux for 24 hours. When the reaction was complete, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of toluene: hexane = 1: 1 to obtain the above-mentioned iridium compound 331 (1.66g, 70%).

[0213] <Preparation of Iridium Compound 332>

[0214]

[0215] In a 250mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M3 (2.18g, 1.5mmol) and ligand L1 (0.47g, 3mmol) were dissolved in toluene (100mL) and the reaction solution was stirred under reflux for 24 hours. When the reaction was completed, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of toluene: hexane = 1: 1 to obtain the above-mentioned iridium compound 332 (1.60g, 63%).

[0216] <Preparation of Iridium Compound 333>

[0217]

[0218] In a 250mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M4 (2.26g, 1.5mmol) and ligand L1 (0.47g, 3mmol) were dissolved in toluene (100mL) and the reaction solution was stirred under reflux for 24 hours. When the reaction was completed, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of toluene: hexane = 1: 1 to obtain the above-mentioned iridium compound 333 (1.78g, 68%).

[0219] <Preparation of Iridium Compound 351>

[0220]

[0221] In a 150 mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M2 (2.01 g, 1.5 mmol) and ligand L2 (0.30 g, 3 mmol) were dissolved in a mixed solvent (2-ethoxyethanol: DMF = 40 mL: 40 mL) and the reaction solution was refluxed and stirred at 135 ° C for 24 hours. When the reaction was completed, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of toluene: hexane = 1: 3 to obtain the above-mentioned iridium compound 351 (1.41 g, 64%).

[0222] <Preparation of Iridium Compound 352>

[0223]

[0224] In a 150 mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M3 (2.18 g, 1.5 mmol) and ligand L2 (0.30 g, 3 mmol) were dissolved in a mixed solvent (2-ethoxyethanol: DMF = 40 mL: 40 mL) and the reaction solution was refluxed and stirred at 135 ° C for 24 hours. When the reaction was completed, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of toluene: hexane = 1: 3 to obtain the above-mentioned iridium compound 352 (1.73 g, 73%).

[0225] <Preparation of Iridium Compound 353>

[0226]

[0227] In a 150 mL round-bottom flask and under a nitrogen atmosphere, iridium precursor M4 (2.26 g, 1.5 mmol) and ligand L2 (0.30 g, 3 mmol) were dissolved in a mixed solvent (2-ethoxyethanol: DMF = 40 mL: 40 mL) and the reaction solution was refluxed and stirred at 135 ° C for 24 hours. When the reaction was completed, the temperature was lowered to room temperature. Then, the organic layer was extracted therefrom using dichloromethane and distilled water, and water was removed therefrom by adding anhydrous magnesium sulfate thereto. The filtrate was obtained by filtration, and the crude product was obtained by decompression. The obtained crude product was purified by column chromatography under the conditions of toluene: hexane = 1: 3 to obtain the above-mentioned iridium compound 353 (1.74 g, 71%).

[0228] This embodiment

[0229] <Present Embodiment 1>

[0230] The substrate is coated with ITO (indium tin oxide) with a thickness of The glass substrate of the thin film was washed, and the glass substrate was ultrasonically cleaned and dried using acetone. HI-1 (N1, N1'-([1, 1'-biphenyl] -4, 4'-diyl) bis (N1, N4, N4-triphenylbenzene -1, 4-diamine)) with a thickness of 60nm as a hole injection material was formed on the prepared ITO transparent electrode by thermal vacuum deposition. NPB as a hole transport material was thermally vacuum deposited on the hole injection layer with a thickness of 80nm. A light-emitting layer was thermally vacuum deposited on the hole transport material. In this regard, the light-emitting layer contains CBP with the following structure as the main material and contains compound 1 as a dopant. The doping concentration is 5%, and the thickness of the light-emitting layer is 30nm. ET-1:Liq (1: 1) (30nm) as a material for an electron transport layer and an electron injection layer was thermally vacuum deposited on the light-emitting layer. Then, 100nm thick aluminum was deposited thereon to form a negative electrode. Thus, an organic light-emitting diode was manufactured. The materials used in the above-mentioned embodiment 1 are as follows.

[0231]

[0232] HI-1 refers to N1,N1'-([1,1'-biphenyl]-4,4'-diyl)bis(N1,N4,N4-triphenylbenzene-1,4-diamine).

[0233] ET-1 refers to 2-(4-(9,10-di(naphthalen-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole.

[0234] <Present Examples 2 to 9 and Comparative Examples 1 to 4>

[0235] The organic light emitting diode of each of Examples 2 to 9 and Comparative Examples 1 to 4 was manufactured in the same manner as Example 1, except that each compound shown in Table 2 below was used as a dopant instead of Compound 1 in Example 1.

[0236] Table 2

[0237]

[0238] The structures of Ref-1 to Ref-4 as dopant materials of Comparative Examples 1 to 4 in Table 2 are as follows.

[0239]

[0240] <Present Examples 10 to 15 and Comparative Examples 5 to 7>

[0241] The organic light emitting diode of each of Examples 10 to 15 and Comparative Examples 5 to 7 was manufactured in the same manner as Example 1, except that each compound shown in Table 3 below was used as a dopant instead of Compound 1 in Example 1.

[0242] Table 3

[0243]

[0244] The structures of Ref-5 to Ref-7 as dopant materials of Comparative Examples 5 to 7 in Table 3 are as follows.

[0245]

[0246] <Present Examples 16 to 20>

[0247] The organic light emitting diode of each of Examples 16 to 20 was manufactured in the same manner as in Example 1, except that each compound shown in Table 4 below was used as the host instead of CBP in Example 1.

[0248] Table 4

[0249]

[0250] The structures of GH1 to GH5 as host materials of the present Examples 16 to 20 of Table 4 are as follows, and the compound names thereof are described in Table 1 above.

[0251]

[0252] <Present Examples 21 to 25>

[0253] The organic light emitting diodes of each of the present examples 21 to 25 were manufactured in the same manner as the present example 4, except that each compound shown in the following Table 5 was used instead of CBP as the host in the present example 4. The structures of the host materials GH1 to GH5 are the same as those described with reference to the present examples 16 to 20.

[0254] Table 5

[0255]

[0256] From the results of Table 2 and Table 3 above, it can be determined that, compared with the organic light-emitting diodes of Comparative Examples 1 to 7, in the organic light-emitting diodes in which the organic metal compounds of Examples 1 to 15 satisfying Chemical Formula 1 according to the present disclosure are used as dopants for the light-emitting layers of the diodes, the operating voltage of the diodes is reduced, and the maximum luminous quantum efficiency, external quantum efficiency (EQE) and lifetime (LT95) of the diodes are improved.

[0257] The scope of protection of the present disclosure should be understood by the scope of the claims, and all technical concepts within the scope of its equivalent should be understood to be included in the scope of the present disclosure. Although the embodiments of the present disclosure have been described in more detail with reference to the accompanying drawings, the present disclosure is not necessarily limited to these embodiments. The present disclosure can be implemented in various modified ways without departing from the scope of the technical concept of the present disclosure. Therefore, the embodiments disclosed in the present disclosure are not intended to limit the technical concept of the present disclosure, but are used to describe the present disclosure. The scope of the technical concept of the present disclosure is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative and non-restrictive in all aspects. The scope of protection of the present disclosure should be interpreted by the claims, and all technical concepts within the scope of the present disclosure should be understood to be included in the scope of the present disclosure.

Claims

1. An organometallic compound represented by the following chemical formula 1: [Chemical formula 1]Ir(L A ) m (L B ) n In chemical formula 1, L A represents a primary ligand and is one selected from the group consisting of the following Chemical Formula 2-1, Chemical Formula 2-2, and Chemical Formula 2-3, L B represents an auxiliary ligand represented by the following chemical formula 3, m and n each represent the number of ligands bound to Ir (iridium), m is 1 or 2, n is 1 or 2, and the sum of m and n is 3, [Chemical formula 2-1] [Chemical formula 2-2] [Chemical formula 2-3] [Chemical formula 3] wherein in each of Chemical Formulae 2-1 to 2-3, X independently represents oxygen, R1 represents an alkyl group, R 2-1 , R 2-2 , R 2-3 , R 3-1、 R 3-2、 R 3-3 , R 3-4 and R 3-5 each independently represents hydrogen, The auxiliary ligand represented by Chemical Formula 3 is a bidentate ligand, and the bidentate ligand is represented by the following Chemical Formula 4 or the following Chemical Formula 5: [Chemical formula 4] [Chemical formula 5] In chemical formula 4, R 4-1 , R 4-2 , R 4-3 , R 4-4 , R 5-1 , R 5-2 , R 5-3 and R 5-4 each independently represents hydrogen, In Chemical Formula 5, R6 and R8 each independently represent one selected from the group consisting of a C1 to C5 straight-chain alkyl group and a C1 to C5 branched-chain alkyl group, and R7 represents hydrogen. 2 . The organometallic compound according to claim 1 , wherein m is 1 and n is 2. The organometallic compound according to claim 1 , wherein m is 2 and n is 1.

4. The organometallic compound according to claim 1, wherein the compound represented by the Chemical Formula 1 comprises one selected from the group consisting of the following compounds 1 to 3, 11 to 12, 16 to 18, 26 to 27, 31 to 33, 41 to 42, 46 to 48, 56 to 57, 61 to 63, 71 to 72, 331 to 333, and 351 to 353: 5 . The organometallic compound according to claim 1 , wherein the compound represented by Chemical Formula 1 is used as a green phosphorescent material.

6. An organic light emitting diode, comprising: a first electrode; a second electrode facing the first electrode; and an organic layer disposed between the first electrode and the second electrode, wherein the organic layer comprises a light-emitting layer, The light-emitting layer comprises the organometallic compound according to any one of claims 1 to 5. 7 . The organic light emitting diode according to claim 6 , wherein the organometallic compound is used as a dopant of the light emitting layer. 8 . The organic light emitting diode according to claim 6 , wherein a host material of the light emitting layer comprises a compound containing a carbazole group.

9. The organic light emitting diode according to claim 8, wherein the compound containing a carbazole group comprises at least one compound selected from the following structures: 10 . The organic light emitting diode according to claim 6 , wherein the organic layer further comprises at least one selected from the group consisting of a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer.

11. An organic light emitting display device, comprising: substrate; a driving element located on the substrate; and An organic light emitting element is disposed on the substrate and connected to the driving element, wherein the organic light emitting element comprises an organic light emitting diode according to any one of claims 6 to 10.

Images