ORGANOMETALLIC COMPOUND, ORGANIC LIGHT-EMITTING DEVICE INCLUDING THE SAME, AND ELECTRONIC APPARATUS INCLUDING THE ORGANIC LIGHT EMITTING DEVICE

An organometallic compound represented by Formula 1, an organic light-emitting device including the same, and an electronic apparatus including the organic light-emitting device:

Formula 1
        M1(Ln1)n1(Ln2)n2. In Formula 1, M1 is a transition metal, Ln1 is a ligand represented by Formula 1A, Ln2 is a ligand represented by Formula 1B, and n1 and n2 are each independently 1 or 2,

descriptions of the other substituents are provided herein.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Korean Patent Application No. 10-2024-0046262, filed on Apr. 4, 2024, in the Korean Intellectual Property Office and all benefits accruing therefrom under 35 U.S.C. § 119, the entire content of which is incorporated by reference herein.

BACKGROUND

The disclosure relates to an organometallic compound, an organic light-emitting device including the same, and an electronic apparatus including the organic light-emitting device.

2. Description of the Related Art

Organic light-emitting devices are so-called self-emissive devices that have excellent characteristics in terms of viewing angles, response time, brightness, driving voltage, response speed, and the like, and produce full-color images.

In an example, an organic light-emitting device includes an anode, a cathode, and an organic layer with an emission layer that is arranged between the anode and the cathode. A hole transport region may be provided between the anode and the emission layer, and an electron transport region may be provided between the emission layer and the cathode. Holes provided from the first electrode move toward the emission layer through the hole transport region, and electrons provided from the second electrode move toward the emission layer through the electron transport region. The holes and the electrons recombine in the emission layer to produce excitons. The excitons may transition from an excited state to a ground state, thereby generating light.

A need remains for an organometallic compound with enhanced photoluminescence properties.

SUMMARY

Provided are a novel organometallic compound, an organic light-emitting device including the same, and an electronic apparatus including the organic light-emitting device.

According to one or more embodiments, provided an organometallic compound represented by Formula 1:

According to another aspect of the disclosure, an organic light-emitting device includes a first electrode, a second electrode, and an organic layer that includes an emission layer and is arranged between the first electrode and the second electrode, wherein the organic layer includes at least one organometallic compound.

According to another aspect of the disclosure, an electronic apparatus includes the organic light-emitting device.

BRIEF DESCRIPTION OF THE DRAWING

The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with FIGURE which is a schematic cross sectional view of an embodiment of an organic light-emitting device.

DETAILED DESCRIPTION

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, “a”, “an,” “the,” and “at least one” do not denote a limitation of quantity, and are intended to include both the singular and plural, unless the context clearly indicates otherwise. For example, “an element” has the same meaning as “at least one element,” unless the context clearly indicates otherwise. “At least one” is not to be construed as limiting “a” or “an.” Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. “Or” means “and/or.” As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

Embodiments are described herein with reference to a cross section illustration that is a schematic illustration of an embodiment. As such, variations from the shapes of the illustration as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figure are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims.

An aspect of the disclosure provides an organometallic compound represented by Formula 1:

wherein M1 in Formula 1 is a transition metal.

For example, M1 may be a first-row transition metal, a second-row transition metal, or a third-row transition metal, of the Periodic Table of Elements.

In an embodiment, M1 may be Ir, Pt, Os, or Rh.

In an embodiment, M1 may be Ir.

In Formula 1, n1 is 1 or 2, and n2 is 1, 2, or 3.

In an embodiment, the sum of n1 and n2 may be 2 or 3.

In an embodiment, M1 may be Ir, and the sum of n1 and n2 may be 3.

In an embodiment, M1 may be Pt, and the sum of n1 and n2 may be 2.

In an embodiment, M1 may be Ir, n1 may be 2, and n2 may be 1.

In Formula 1, Ln1 is a ligand represented by Formula 1A:

In an embodiment, X1 may be N.

In an embodiment, X2 may be C.

In Formula 1A, R11 to R18 are each independently a group represented by Formula 2, hydrogen, deuterium, —F, —Cl, —Br, —I, —SF5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C1-C60 alkylthio group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C1-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C7-C60 alkyl aryl group, a substituted or unsubstituted C7-C60 aryl alkyl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted C2-C60 alkyl heteroaryl group, a substituted or unsubstituted C2-C60 heteroaryl alkyl group, a substituted or unsubstituted C1-C60 heteroaryloxy group, a substituted or unsubstituted C1-C60 heteroarylthio group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, Si(Q1)(Q2)(Q3), —Ge(Q1)(Q2)(Q3), —N(Q4)(Q5), —B(Q6)(Q7), —P(Q8)(Q9), or —P(═O)(Q8)(Q9), provided that

wherein, in Formula 2, L1 may be a single bond, a C5-C30 carbocyclic group unsubstituted or substituted with at least one R10, or a C1-C30 heterocyclic group unsubstituted or substituted with at least one R10.

In an embodiment, L1 may be a single bond, a substituted or unsubstituted C3-C10 cycloalkylene group, a substituted or unsubstituted C1-C10 heterocycloalkylene group, a substituted or unsubstituted C3-C10 cycloalkenylene group, a substituted or unsubstituted C2-C10 heterocycloalkenylene group, a substituted or unsubstituted C6-C60 arylene group, a substituted or unsubstituted C1-C60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group.

In an embodiment, L1 may be: a single bond; or

In an embodiment, a1 may be 1.

In an embodiment, Z1 may be —Si(Q1)(Q2)(Q3), —Ge(Q1)(Q2)(Q3), —F, —CF3, —CF2H, —CFH2, or a group represented by one of Formulae 9-101 to 9-114 or 10-601 to 10-636:

In an embodiment, the group represented by Formula 2 may be a group represented by one of Formulae 3-1 to 3-4:

In an embodiment, R11 to R18 may each independently be: the group represented by Formula 2, hydrogen, deuterium, —F, —Cl, —Br, —I, -CD3, -CD2H, —CDH2, —CF3, —CF2H, —CFH2, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, —SF5, a C1-C20 alkyl group, or a C1-C20 alkoxy group;

In Formula 1, Ln2 may be a ligand represented by Formula 1B:

In an embodiment, X31 and X32 may each be O.

In Formulae 1A and 1B, R10, R21 to R25, and R31 to R33 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C1-C60 alkylthio group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C1 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C1-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C7-C60 alkyl aryl group, a substituted or unsubstituted C7-C60 aryl alkyl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted C2-C60 alkyl heteroaryl group, a substituted or unsubstituted C2-C60 heteroaryl alkyl group, a substituted or unsubstituted C1-C60 heteroaryloxy group, a substituted or unsubstituted C1-C60 heteroarylthio group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q1)(Q2)(Q3), —Ge(Q1)(Q2)(Q3), —N(Q4)(Q5), —B(Q6)(Q7), —P(Q8)(Q9), or —P(═O)(Q8)(Q9).

In an embodiment, R10, R21 to R25, and R31 to R33 may each independently be: hydrogen, deuterium, —F, —Cl, —Br, —I, -CD3, -CD2H, —CDH2, —CF3, —CF2H, —CFH2, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, —SF5, a C1-C20 alkyl group, or a C1-C20 alkoxy group;

In an embodiment, R11 to R18 may each independently be: the group represented by Formula 2, hydrogen, deuterium, —F, —CF3, —CF2H, —CFH2, or a C1-C10 alkyl group; or

In Formulae 9-1 to 9-67, 9-101 to 9-114, 9-201 to 9-244, 10-1 to 10-154, 10-201 to 10-350, and 10-601 to 10-636, * indicates a binding site to a neighboring atom, Ph is a phenyl group, TMS is a trimethylsilyl group, and TMG is a trimethylgermyl group.

In an embodiment, one or two of R11 to R18 may be the group represented by Formula 2. For example, R15 and/or R16 may be the group represented by Formula 2.

In an embodiment, R21 to R25 may each be hydrogen.

In Formula 1A, at least two neighboring substituents among R11 to R18 and R21 to R25 may optionally be bonded together to form a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group.

In an embodiment, at least two among R11 to R18 and R21 to R25 may optionally be bonded together, via a single bond, a double bond, or a first linking group, to form a C5-C30 carbocyclic group unsubstituted or substituted with at least one R10a or a C1-C30 heterocyclic group unsubstituted or substituted with at least one R10a (e.g., a fluorene group, a xanthene group, an acridine group, and the like, each unsubstituted or substituted with at least one R10a). R10a is as described in connection with R10.

In an embodiment, examples of “the C5-C30 carbocyclic group unsubstituted or substituted with at least one R10a” or “the C1-C30 heterocyclic group unsubstituted or substituted with at least one R10a” include a benzene group, a naphthalene group, a cyclopentane group, a cyclopentadiene group, a cyclohexane group, a cycloheptane group, a bicyclo[2.2.1]heptane group, a furan group, a thiophene group, a pyrrole group, a silole group, an indene group, a benzofuran group, a benzothiophene group, an indole group, a benzosilole group, a fluorene group, a xanthene group, an acridine group, and the like, each unsubstituted or substituted with at least one R10a. R10a is the same as described in connection with R10. The C5-C30 carbocyclic group and the C1-C30 heterocyclic group are each the same as described herein.

The first linking group may be selected from *—N(R8)—*, *—B(R8)—*, *—P(R8)—*′, *—C(R8)(R9)—*′, *—Si(R8)(R9)—*′, *—Ge(R8)(R9)—*′, *—S—*′, *—Se—*′, *—O—*′, *—C(═O)—*, *—S(═O)—*′, *—S(═O)2—*′, *—C(R8)═*′, *═C(R8)—*′, *—C(R8)═C(R)—*′, *—C(═S)—*′, and *—C≡C—*′, wherein R8 and R9 are as described in connection with R10, and * and *′ each indicate a binding site to a neighboring atom.

In an embodiment, Q1 to Q9, Q11 to Q19, Q21 to Q29 and Q31 to Q39 may each independently be:

In an embodiment, Ln1 may be a ligand represented by one of Formulae 1A-1 to 1A-8:

In an embodiment, the organometallic compound may be represented by one of Formulae 11-1 to 11-32:

In an embodiment, the organometallic compound may be electrically neutral.

In an embodiment, the organometallic compound may be one of Compounds 1 to 94:

The organometallic compound represented by Formula 1 may satisfy the aforementioned structure of Formula 1. In detail, the ligand represented by Formula 1A includes the group represented by Formula 2 for at least one of R11 to R18, and may also has a structure in which a cyano group is substituted at a specific position of the naphthalene ring. Due to this structure, the organometallic compound represented by Formula 1 may has improved structural stability, and thus may have excellent lifespan characteristics, excellent luminescence characteristics, and a reduced roll-off phenomenon, and may be suitable for use as a luminescent material with high color purity by controlling an emission wavelength range.

In addition, the organometallic compound represented by Formula 1 has excellent electrical mobility, and thus, an electronic device, e.g., an organic light-emitting device, including the organometallic compound may exhibit a low driving voltage, high efficiency, a long lifespan, and have a reduced roll-off phenomenon.

In addition, the organometallic compound represented by Formula 1 has improved stability (e.g., photochemical stability), and thus, an electronic device, e.g., an organic light-emitting device, including the organometallic compound exhibit high luminescence efficiency, a long lifespan, and a high color purity.

In an embodiment, a full width at half maximum (FWHM) of an emission peak of an emission spectrum or electroluminescence spectrum of the organometallic compound may be 70 nanometers (nm) or less. For example, the FWHM of an emission peak of an emission spectrum or electroluminescence spectrum of the organometallic compound may be about 20 nm to about 70 nm, about 30 nm to about 65 nm, about 40 nm to about 63 nm, or about 45 nm to about 62 nm.

In an embodiment, a maximum emission wavelength (emission peak wavelength, λmax) in an emission spectrum or electroluminescence spectrum of the organometallic compound may be about 580 nm to about 750 nm.

Synthesis methods for the organometallic compound represented by Formula 1 may be recognized by those skilled in the art with reference to Synthesis Examples to be described herein.

The organometallic compound represented by Formula 1 may be suitable for use in an organic layer of an organic light-emitting device, for example, as a dopant in an emission layer of the organic layer. Accordingly, another aspect of the disclosure provides an organic light-emitting device including: a first electrode; a second electrode; and an organic layer that is arranged between the first electrode and the second electrode. The organic layer includes an emission layer and at least one of the organometallic compound represented by Formula 1.

The organic light-emitting device may exhibit excellent characteristics in terms of driving voltage, current efficiency, power efficiency, external quantum efficiency, lifespan, and/or color purity, by including the organic layer including the organometallic compound represented by Formula 1, and accordingly, a roll-off phenomenon may be reduced and the FWHM of an emission peak of an electroluminescence spectrum may be relatively narrow.

The organometallic compound represented by Formula 1 may be used between a pair of electrodes of the organic light-emitting device. For example, the organometallic compound represented by Formula 1 may be included in the emission layer. In this regard, the organometallic compound may serve as a dopant, and the emission layer may further include a host (that is, in the emission layer, an amount of the organometallic compound represented by Formula 1 may be smaller than an amount of the host, e.g. on a weight basis).

In an embodiment, the emission layer may emit red light. For example, the emission layer may emit red light having a maximum emission wavelength of about 580 nm to about 750 nm.

The expression “an organic layer includes at least one organometallic compound represented by Formula 1” as used herein may include a case in which an organic layer includes identical organometallic compounds represented by Formula 1 and a case in which an organic layer includes two or more types of different organometallic compounds represented by Formula 1.

For example, the organic layer may include, as the organometallic compound, only Compound 1. In this regard, Compound 1 may be included in the emission layer of the organic light-emitting device. In one or more embodiments, the organic layer may include, as the organometallic compound, Compound 1 and Compound 2. In this regard, Compound 1 and Compound 2 may be in an identical layer (for example, Compound 1 and Compound 2 may both be in the emission layer).

In an embodiment, the first electrode may be an anode, which is a hole injection electrode, and the second electrode may be a cathode, which is an electron injection electrode. In one or more embodiments, the first electrode may be a cathode, which is an electron injection electrode, and the second electrode may be an anode, which is a hole injection electrode.

In an embodiment, in the organic light-emitting device, the first electrode may be an anode, the second electrode may be a cathode, and the organic layer may further include a hole transport region arranged between the first electrode and the emission layer and an electron transport region arranged between the emission layer and the second electrode, wherein the hole transport region may include a hole injection layer, a hole transport layer, an electron blocking layer, a buffer layer, or a combination thereof, and the electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or a combination thereof.

The term “organic layer” as used herein refers to a single layer and/or a plurality of layers arranged between the first electrode and the second electrode of the organic light-emitting device. The “organic layer” may include, in addition to an organic compound, an organometallic complex including a metal.

FIGURE is a schematic cross-sectional view of an organic light-emitting device 10 according to an embodiment. Hereinafter, a structure and a manufacturing method of the organic light-emitting device 10 according to an embodiment will be described in connection with the FIGURE. The organic light-emitting device 10 has a structure in which a first electrode 11, an organic layer 15, and a second electrode 19 are sequentially stacked.

A substrate may be additionally arranged under the first electrode 11 or on the second electrode 19. For use as the substrate, a substrate generally used in organic light-emitting devices, e.g., a glass substrate or a transparent plastic substrate, having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water repellency may be used.

The first electrode 11 may be formed by, for example, depositing or sputtering, onto the substrate, a material for forming the first electrode 11. The first electrode 11 may be an anode. The material for forming the first electrode 11 may be selected from materials with a high work function for easy hole injection. The first electrode 11 may be a reflective electrode, a transflective electrode, or a transmissive electrode. The material for forming the first electrode 11 may be indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), or zinc oxide (ZnO). In one or more embodiments, the material for forming the first electrode 11 may be a metal, such as magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag).

The first electrode 11 may have a single-layer structure or a multi-layer structure including a plurality of layers. For example, the first electrode 11 may have a three-layer structure of ITO/Ag/ITO, but embodiments are not limited thereto.

The organic layer 15 is arranged on the first electrode 11.

The organic layer 15 may include an emission layer, and may further include a hole transport region and an electron transport region.

The hole transport region may be arranged between the first electrode 11 and the emission layer.

The hole transport region may include a hole injection layer, a hole transport layer, an electron blocking layer, a buffer layer, or any combination thereof.

The hole transport region may include only either a hole injection layer or a hole transport layer. The hole transport region may have a hole injection layer/hole transport layer structure or a hole injection layer/hole transport layer/electron blocking layer structure, wherein the layers of each structure may be sequentially stacked from the first electrode 11 in its respective stated order, but the structure of the hole transport region is not limited thereto.

When the hole transport region includes a hole injection layer, the hole injection layer may be formed on the first electrode 11 by using various methods, for example, vacuum deposition, spin coating, casting, and/or Langmuir-Blodgett (LB) deposition.

When the hole injection layer is formed by vacuum deposition, the deposition conditions may vary according to a material that is used to form the hole injection layer, and the structure and thermal characteristics of the hole injection layer. For example, the deposition conditions may include a deposition temperature of about 100° C. to about 500° C., a vacuum pressure of about 10−8 torr to about 10−3 torr, and a deposition rate of about 0.01 angstroms per second (Å/sec) to about 100 Å/sec. However, the deposition conditions are not limited thereto.

When the hole injection layer is formed by a spin coating method, coating conditions may vary depending on a compound used as a material for forming the hole injection layer, a structure and thermal characteristics of the desired hole injection layer, and the like. For example, a coating rate may be selected from about 2,000 revolutions per minute (rpm) to about 5,000 rpm, and a temperature at which heat treatment is performed to remove a solvent after coating may be selected from about 80° C. to about 200° C., but embodiments are not limited thereto.

In this regard, conditions for forming the hole transport layer and the electron blocking layer may be understood by referring to the conditions for forming the hole injection layer.

In Formula 201, xa and xb may each independently be an integer from 0 to 5, or may each independently be 0, 1, or 2. For example, xa may be 1, and xb may be 0, but embodiments are not limited thereto.

In Formulae 201 and 202, R11 to R108, R111 to R119, and R121 to R124 may each independently be:

In an embodiment, the compound represented by Formula 201 may be represented by Formula 201A, but embodiments are not limited thereto:

For example, the compound represented by Formula 201 and the compound represented by Formula 202 may include Compounds HT1 to HT20, but embodiments are not limited thereto:

The hole transport region may further include, in addition to the aforementioned materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole transport region.

The hole transport region may further include a buffer layer.

The buffer layer may compensate for an optical resonance distance according to a wavelength of light emitted from the emission layer 15, and thus, efficiency of a formed organic light-emitting device may be improved.

Then, the emission layer may be formed on the hole transport region by vacuum deposition, spin coating, casting, LB deposition, or the like. When the emission layer is formed by vacuum deposition or spin coating, the deposition or coating conditions may be similar to those applied in forming the hole injection layer although the deposition or coating conditions may vary depending on a material to be used.

Meanwhile, when the hole transport region includes an electron blocking layer, a material for forming the electron blocking layer may be selected from the aforementioned materials for forming the hole transport region and host materials to be described later, but embodiments are not limited thereto. For example, when the hole transport region includes an electron blocking layer, a material for forming the electron blocking layer may be mCP which will be described later.

The emission layer may include a host and a dopant, and the dopant may include the organometallic compound represented by Formula 1.

In an embodiment, the host may include at least one of TPBi, TBADN, ADN (also referred to as “DNA”), CBP, CDBP, TCP, mCP, Compound H50, and Compound H51, and Compound RH3:

In one or more embodiments, the host may further include a compound represented by Formula 301:

In Formula 301, Ar113 to Ar116 may each independently be:

In Formula 301, g, h, i, and j may each independently be an integer from 0 to 4, and for example, may each independently be 0, 1, or 2.

In Formula 301, Ar113 to Ar116 may each independently be:

In one or more embodiments, the host may include a compound represented by Formula 302:

wherein, in Formula 302, Ar122 to Ar125 are each as described in connection with Ar113 in Formula 301.

In Formula 302, Ar126 and Ar127 may each independently be a C1-C10 alkyl group (e.g., a methyl group, an ethyl group, or a propyl group).

In Formula 302, k and I may each independently be an integer from 0 to 4. For example, k and I may each independently be 0, 1, or 2.

When the organic light-emitting device 10 is a full-color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and a blue emission layer. Due to a structure in which a red emission layer, a green emission layer, and/or a blue emission layer is stacked, the emission layer may emit white light.

When the emission layer includes a host and a dopant, an amount of the dopant may be about 0.01 parts by weight to about 15 parts by weight based on 100 parts by weight of the host, but embodiments are not limited thereto.

A thickness of the emission layer may be about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is these ranges, excellent luminescence characteristics may be obtained without a substantial increase in driving voltage.

An electron transport region may be arranged on the emission layer.

The electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

For example, the electron transport region may have a hole blocking layer/electron transport layer/electron injection layer structure or an electron transport layer/electron injection layer structure, but embodiments are not limited thereto. The electron transport layer may have a single-layer structure or a multi-layer structure including a plurality of layers.

Conditions for forming the hole blocking layer, the electron transport layer, and the electron injection layer which constitute the electron transport region may be understood by referring to the conditions for forming the hole injection layer.

When the electron transport region includes a hole blocking layer, the hole blocking layer may include, for example, at least one of BCP, Bphen, or BAlq, but embodiments are not limited thereto:

A thickness of the hole blocking layer may be about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. When the thickness of the hole blocking layer is these ranges, excellent hole blocking characteristics may be obtained without a substantial increase in driving voltage.

The electron transport layer may include at least one of BCP, Bphen, Alq3, BAlq, TAZ, or NTAZ:

The electron transport layer may include at least one of Compounds ET1 to ET25, but embodiments are not limited thereto:

A thickness of the electron transport layer may be about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thickness of the electron transport layer is these ranges, satisfactory electron transporting characteristics may be obtained without a substantial increase in driving voltage.

The electron transport layer may further include, in addition to the aforementioned materials, a metal-containing material.

The electron transport region may also include an electron injection layer that facilitates the injection of electrons from the second electrode 19.

The electron injection layer may include LiQ, LiF, NaCl, CsF, Li2O, BaO, or any combination thereof.

A thickness of the electron injection layer may be about 1 Å to about 100 Å, for example, about 3 Å to about 90 Å. When the thickness of the electron injection layer is these ranges, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.

The second electrode 19 is arranged on the organic layer 15. The second electrode 19 may be a cathode. A material for forming the second electrode 19 may be metal, an alloy, an electrically conductive compound, or a combination thereof, each having a relatively low work function. For example, the material for forming the second electrode 19 may include lithium (Li), magnesium (Mg), aluminum (AI), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), and the like. To manufacture a top-emission type light-emitting device, a transmissive electrode formed using ITO or IZO may be used as the second electrode 19.

Hereinbefore, the organic light-emitting device has been described with reference to the FIGURE, but embodiments are not limited thereto.

Another aspect of the present disclosure provides a diagnostic composition including at least one organometallic compound represented by Formula 1.

The organometallic compound represented by Formula 1 may be able to provide high luminescence efficiency, and thus the diagnostic composition including the organometallic compound may have high diagnostic efficiency.

The diagnostic composition may be used in various applications including a diagnosis kit, a diagnosis reagent, a biosensor, a biomarker, and the like.

The term “C1-C60 alkyl group” as used herein refers to a linear or branched saturated aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and non-limiting examples thereof include a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isoamyl group, a hexyl group, and the like. The term “C1-C60 alkylene group” as used herein refers to a divalent group having the same structure as the C1-C60 alkyl group.

The term “C1-C60 alkoxy group” as used herein refers to a monovalent group represented by —OA101 (wherein A101 is the C1-C60 alkyl group), and examples thereof include a methoxy group, an ethoxy group, an isopropyloxy group, and the like.

The term “C1-C60 alkylthio group” as used herein refers to a monovalent group represented by —SA101 (wherein A101 is the C1-C60 alkyl group), and examples thereof include a thiomethyl group, a thioethyl group, and the like.

The term “C2-C60 alkenyl group” as used herein refers to a hydrocarbon group formed by substituting at least one carbon-carbon double bond in the middle or at the terminus of the C2-C60 alkyl group, and examples thereof include an ethenyl group, a propenyl group, a butenyl group, and the like. The term “C2-C60 alkenylene group” as used herein refers to a divalent group having the same structure as the C2-C60 alkenyl group.

The term “C2-C60 alkynyl group” as used herein refers to a hydrocarbon group formed by substituting at least one carbon-carbon triple bond in the middle or at the terminus of the C2-C60 alkyl group, and examples thereof include an ethynyl group, a propynyl group, and the like. The term “C2-C60 alkynylene group” as used herein refers to a divalent group having the same structure as the C2-C60 alkynyl group.

The term “C3-C10 cycloalkyl group” as used herein refers to a monovalent saturated hydrocarbon cyclic group having 3 to 10 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and the like. The term “C3-C10 cycloalkylene group” as used herein refers to a divalent group having the same structure as the C3-C1 cycloalkyl group.

The term “C1-C1 heterocycloalkyl group” as used herein refers to a monovalent cyclic group having at least one heteroatom selected from B, N, O, P, Si, S, Se, or Ge as a ring-forming atom and 1 to 10 carbon atoms, and non-limiting examples thereof include a tetrahydrofuranyl group, a tetrahydrothiophenyl group, and the like. The term “C1-C1 heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C1-C1 heterocycloalkyl group.

The term “C1-C10 heterocycloalkenyl group” as used herein refers to a monovalent cyclic group that has at least one hetero atom selected from B, N, O, P, Si, S, Se or Ge as a ring-forming atom, 1 to 10 carbon atoms, and at least one carbon-carbon double bond in the cyclic structure thereof. Examples of the C1-C10 heterocycloalkenyl group include a 2,3-dihydrofuranyl group, a 2,3-dihydrothiophenyl group, and the like. The term “C1-C10 heterocycloalkenylene group” as used herein refers to a divalent group having the same structure as the C1-C10 heterocycloalkenyl group.

The term “C6-C60 aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and the term “C6-C60 arylene group” as used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Examples of the C6-C60 aryl group include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a chrysenyl group, and the like. When the C6-C60 aryl group and the C6-C60 arylene group each include two or more rings, the rings may be fused with each other. The term “C7-C6a alkyl aryl group” refers to a C6-C60 aryl group substituted with at least one C1-C60 alkyl group. The term “C7-C60 aryl alkyl group” refers to a C1-C60 alkyl group substituted with at least one C6-C60 aryl group.

The term “C1-C60 heteroaryl group” as used herein refers to a monovalent group having a cyclic aromatic system having at least one heteroatom selected from B, N, O, P, Si, S, Se, or Ge as a ring-forming atom and 1 to 60 carbon atoms, and the term “C1-C60 heteroarylene group” as used herein refers to a divalent group having a cyclic aromatic system having at least one heteroatom selected from B, N, O, P, Si, S, Se, or Ge as a ring-forming atom and 1 to 60 carbon atoms. Examples of the C1-C60 heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, and the like. When the C1-C60 heteroaryl group and the C1-C60 heteroarylene group each include two or more rings, the rings may be fused with each other. The term “C2-C60 alkyl heteroaryl group” refers to a C1-C60 heteroaryl group substituted with at least one C1-C60 alkyl group. The term “C2-C60 heteroaryl alkyl group” refers to a C1-C60 alkyl group substituted with at least one C1-C60 heteroaryl group.

The term “C6-C60 aryloxy group” as used herein refers to —OA102 (wherein A102 is the C6-C60 aryl group), and the term “C6-C60 arylthio group” as used herein refers to -SA103 (wherein A103 is the C6-C60 aryl group).

The term “C1-C60 heteroaryloxy group” as used herein indicates —OA104 (wherein A104 is the C1-C60 heteroaryl group), and the term “C1-C60 heteroarylthio group” as used herein indicates —SA105 (wherein A105 is the C1-C60 heteroaryl group).

The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group (for example, having 1 to 60 carbon atoms) having two or more rings condensed with each other, a heteroatom selected from B, N, O, P, Si, S, Se, or Ge, other than carbon atoms, as a ring-forming atom, and no aromaticity in the entire molecular structure thereof. Examples of the monovalent non-aromatic condensed heteropolycyclic group include a carbazolyl group and the like. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

The term “C5-C30 carbocyclic group” as used herein refers to a saturated or unsaturated cyclic group having, as a ring-forming atom, 5 to 30 carbon atoms only. The C5-C30 carbocyclic group may be a monocyclic group or a polycyclic group.

The term “C1-C30 heterocyclic group” as used herein refers to a saturated or unsaturated cyclic group having at least one heteroatom selected from B, N, O, P, Si, S, Se, or Ge, other than 1 to 30 carbon atoms, as a ring-forming atom. The C1-C30 heterocyclic group may be a monocyclic group or a polycyclic group.

In the present specification, TMS indicates *—Si(CH3)3, and TMG indicates *—Ge(CH3)3.

Hereinafter, compounds and organic light-emitting devices, according to one or more embodiments, will be described in further detail with reference to Synthesis Example and Examples. However, the following examples are not intended to limit the scope of the disclosure. The wording “‘B’ was used instead of ‘A’” used in describing Synthesis Examples means that an amount of ‘A’ used was identical to an amount of ‘B’ used, in terms of a molar equivalent.

EXAMPLES

Synthesis Example 1: Synthesis of Compound 1

(1) Synthesis of Intermediate L1

4-Chloro-7-(trimethylsilyl)benzo[f]isoquinoline (1.5 grams (g), 5.25 millimoles (mmol)) was mixed with 50 milliliters (mL) of EtOH and 5 mL of water, and 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-naphthonitrile (1.7 g, 6.30 mmol), Pd(PPh3)4 (0.4 g, 0.37 mmol), and K2CO3 (1.8 g, 13.1 mmol) were added to the mixed solution. The resulting solution was heated at reflux for 18 hours. The results obtained therefrom were concentrated under reduced pressure, and the resulting mixture was subjected to an extraction process using ethyl acetate and water. The organic layer collected therefrom was then dried over magnesium sulfate, distilled under reduced pressure, and purified by liquid chromatography, to provide 1.9 g (yield of 90%) of Intermediate L1.

LC-MS mass to charge ratio (m/z)=404 (M+H)+. (2) Synthesis of Intermediate L1 Dimer

Intermediate L1 (1.5 g, 3.7 mmol) and iridium chloride hydrate (0.68 g, 1.9 mmol) were mixed with 60 mL of ethoxyethanol and 15 mL of distilled water. The mixed solution was heated at reflux for 24 hours. The reaction mixture as then allowed to cool to room temperature, and the resulting solid was filtered and washed with water/methanol/hexane in the stated order. The crude product obtained without further purification was dried in a vacuum oven, to provide 1.2 g of Intermediate L1 Dimer.

(3) Synthesis of Compound 1

Intermediate L1 Dimer (1.0 g, 0.48 mmol), acetylacetone (0.24 g, 2.4 mmol), and Na2CO3 (0.33 g, 2.4 mmol) were mixed with 40 mL of ethoxyethanol. The mixed solution was stirred at 100° C. for 24 hours. After 24 hours, the reaction mixture was cooled to room temperature, and the resulting solid was purified by liquid chromatography, to provide 0.4 g (yield of 38%) of Compound 1. LC-MS m/z=1095 (M+H)+.

Synthesis Example 2: Synthesis of Compound 2

(1) Synthesis of Intermediate L2

Intermediate L2 (1.6 g, yield of 86%) was synthesized using the same synthesis method for Intermediate L1 of Synthesis Example 1, except that 4-chloro-7-(trimethylgermyl)benzo[f]isoquinoline was used instead of 4-chloro-7-(trimethylsilyl)benzo[f]isoquinoline. LC-MS m/z=449 (M+H)+.

(2) Synthesis of Intermediate L2 Dimer

Intermediate L2 Dimer was synthesized using the same synthesis method for Intermediate L1 Dimer of Synthesis Example 1, except that Intermediate L2 was used instead of Intermediate L1.

(3) Synthesis of Compound 2

Compound 2 (0.3 g, yield of 35%) was synthesized using the same synthesis method for Compound 1 of the Synthesis Example 1, except that Intermediate L2 Dimer was used instead of Intermediate L1 Dimer. LC-MS m/z=1187 (M+H)+.

Synthesis Example 3: Synthesis of Compound 3

(1) Synthesis of Intermediate L3

Intermediate L3 (1.4 g, yield of 85%) was synthesized using the same synthesis method for Intermediate L1 of Synthesis Example 1, except that 4-chloro-7-(trifluoromethyl)benzo[f]isoquinoline was used instead of 4-chloro-7-(trimethylsilyl)benzo[f]isoquinoline. LC-MS m/z=399 (M+H)+.

(2) Synthesis of Intermediate L3 Dimer

Intermediate L3 Dimer was synthesized by using the same synthesis method for Intermediate L1 Dimer of Synthesis Example 1, except that Intermediate L3 was used instead of Intermediate L1.

(3) Synthesis of Compound 3

Compound 3 (0.3 g, yield of 41%) was synthesized using the same synthesis method for Compound 1 of the Synthesis Example 1, except that Intermediate L3 Dimer was used instead of Intermediate L1 Dimer. LC-MS m/z=1087 (M+H)+.

Synthesis Example 4: Synthesis of Compound 4

(1) Synthesis of Intermediate L4

Intermediate L4 (1.1 g, yield of 80%) was synthesized using the same synthesis method for Intermediate L1 of Synthesis Example 1, except that 4-chloro-7-fluorobenzo[f]isoquinoline was used instead of 4-chloro-7-(trimethylsilyl)benzo[f]isoquinoline. LC-MS m/z=349 (M+H)+.

(2) Synthesis of Intermediate L4 Dimer

Intermediate L4 Dimer was synthesized using the same synthesis method for Intermediate L1 Dimer of Synthesis Example 1, except that Intermediate L4 was used instead of Intermediate L1.

(3) Synthesis of Compound 4

Compound 4 (0.4 g, yield of 45%) was synthesized using the same synthesis method for Compound 1 of the Synthesis Example 1, except that Intermediate L4 Dimer was used instead of Intermediate L1 Dimer. LC-MS m/z=987 (M+H)+.

Synthesis Example 5: Synthesis of Compound 7

(1) Synthesis of Intermediate L7

Intermediate L7 (1.0 g, yield of 75%) was synthesized using the same synthesis method for Intermediate L1 of Synthesis Example 1, except that 4-chloro-8-(trifluoromethyl)benzo[f]isoquinoline was used instead of 4-chloro-7-(trimethylsilyl)benzo[f]isoquinoline. LC-MS m/z=399 (M+H)+.

(2) Synthesis of Intermediate L7 Dimer

Intermediate L7 Dimer was synthesized using the same synthesis method for Intermediate L1 Dimer of Synthesis Example 1, except that Intermediate L7 was used instead of Intermediate L1.

(3) Synthesis of Compound 7

Compound 7 (0.4 g, yield of 48%) was synthesized using the same synthesis method for Compound 1 of the Synthesis Example 1, except that Intermediate L7 Dimer was used instead of Intermediate L1 Dimer. LC-MS m/z=1087 (M+H)+.

Synthesis Example 6: Synthesis of Compound 27

(1) Synthesis of Intermediate L27

Intermediate L27 (0.8 g, yield of 63%) was synthesized using the same synthesis method for Intermediate L1 of Synthesis Example 1, except that 4-chloro-7-(4-(trifluoromethyl)phenyl)benzo[f]isoquinoline was used instead of 4-chloro-7-(trimethylsilyl)benzo[f]isoquinoline. LC-MS m/z=475 (M+H)+.

(2) Synthesis of Intermediate L27 Dimer

Intermediate L27 Dimer was synthesized using the same synthesis method for Intermediate L1 Dimer of Synthesis Example 1, except that Intermediate L27 was used instead of Intermediate L1.

(3) Synthesis of Compound 27

Compound 27 (0.3 g, yield of 32%) was synthesized using the same synthesis method for Compound 1 of the Synthesis Example 1, except that Intermediate L27 Dimer was used instead of Intermediate L1 Dimer. LC-MS m/z=1239 (M+H)+.

As an anode, an ITO-patterned glass substrate was cut to a size of 50 millimeters (mm)×50 mm×0.5 mm, sonicated in isopropyl alcohol and pure water for 5 minutes each, cleaned by irradiation of ultraviolet rays and exposure to ozone for 30 minutes, and then mounted on a vacuum deposition apparatus.

Compound HT3 and F12 (p-dopant) were vacuum co-deposited in a weight ratio of 98:2 on the anode to form a hole injection layer having a thickness of 100 Å, and Compound HT3 was vacuum-deposited on the hole injection layer to form a hole transport layer having a thickness of 1,600 Å.

Subsequently, Compound RH3 (host) and Compound 1 (dopant) were co-deposited in a weight ratio of 97:3 on the hole transport layer to form an emission layer having a thickness of 400 Å.

Then, Compound ET3 and LiQ (n-dopant) were co-deposited in a volume ratio of 50:50 on the emission layer to form an electron transport layer having a thickness of 350 Å, LiQ (n-dopant) was vacuum deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, and Al was vacuum-deposited on the electron injection layer to form a cathode having a thickness of 1,000 Å, thereby completing the manufacture of an organic light-emitting device.

Examples 2 to 6 and Comparative Examples 1 to 3

Organic light-emitting devices were manufactured in the same manner as in Example 1, except that in forming an emission layer, for use as a dopant, corresponding compounds shown in Table 1 were used instead of Compound 1.

For the organic light-emitting devices of Examples 1 to 6 and Comparative Examples 1 to 3, the driving voltage, the maximum external quantum efficiency (Max EQE), maximum emission wavelength (λmax) and FWHM of an emission spectrum, and roll-off ratio were evaluated, and results thereof are shown in Table 1. For testing evaluation, a current-voltage meter (Keithley 2400) and a luminance meter (Minolta Cs-1000A) were used. The roll-off ratio was calculated according to Equation 20, and the calculated value is shown as a relative value in Table 1:

Dopant in
Driving
Max

the emission
voltage
EQE
λmax
FWHM
ratio

As shown in Table 1, the organic light-emitting devices of Examples 1 to 6 had a low driving voltage, high external quantum efficiency, a narrow FWHM, and a reduced roll-off ratio. Furthermore, the organic light-emitting devices of Examples 1 to 6 had lower driving voltage, higher external quantum efficiency, equivalent FWHM and lower roll-off ratio, compared to the organic light-emitting devices of Comparative Examples 1 to 3.

According to the one or more embodiments, an organometallic compound represented by Formula 1 may have excellent electrical characteristics and excellent thermal stability. Accordingly, an electronic device, e.g., an organic light-emitting device, utilizing the organometallic compound may have a low driving voltage, high efficiency, a long lifespan, a reduced roll-off ratio, and a relatively narrow FWHM of an emission peak of an electroluminescence spectrum.

Thus, due to the use of the organometallic compound, a high-quality organic light-emitting device may be implemented. In addition, an electronic apparatus including the organic light-emitting device may be provided.