Organometallic compound and organic light-emitting device including the same

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2017-0155814, filed on Nov. 21, 2017, in the Korean Intellectual Property Office, the entire content of which is incorporated herein by reference.

BACKGROUND
1. Field

One or more embodiments of the present disclosure relate to an organometallic compound and an organic light-emitting device including the same.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices that can produce full-color images, and may also have wide viewing angles, high contrast ratios, short response times, and excellent characteristics in terms of brightness, driving voltage, and response speed, compared to devices in the related art.

An example organic light-emitting device may include a first electrode on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode sequentially stacked on the first electrode. Holes provided from the first electrode may move toward the emission layer through the hole transport region, and electrons provided from the second electrode may move toward the emission layer through the electron transport region. Carriers (such as holes and electrons) may recombine in the emission layer to produce excitons. These excitons may transition from an excited state to a ground state to thereby generate light.

SUMMARY

One or more embodiments of the present disclosure relate to a novel organometallic compound and an organic light-emitting device including the same.

Additional aspects of embodiments will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.

One or more aspects of embodiments of the present disclosure provide an organometallic compound represented by Formula 1:

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In Formula 1,

M₁₁may be selected from platinum (Pt), palladium (Pd), copper (Cu), silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), and thulium (Tm),

A₁₁to A₁₆may each independently be selected from a C₅-C₆₀carbocyclic group and a C₁-C₆₀heterocyclic group,

Y₁₁to Y₁₄may each independently be N or C,

T₁₁to T₁₄may each independently be selected from a single bond, *—O—*′, and *—S—*′,

L₁₁to L₁₃may each independently be selected from a single bond, *—O—*′, *—S—*′, *—C(R₁₇)(R₁₈)—*′, *—C(R₁₇)═*′, *═C(R₁₇)—*′, *—C(R₁₇)═C(R₁₈)—*′, *—C(═O)—*′, *—C(═S)—*′, *—C═C—*′, *—B(R₁₇)—*′, *—N(R₁₇)—*′, *—P(R₁₇)—*′, *—Si(R₁₇)(R₁₈)—*′, *—P(R₁₇)(R₁₈)—*′, and *—Ge(R₁₇)(R₁₈)—*′,

a11 to a13 may each independently be selected from 0, 1, 2, and 3,

when a11 is zero, A₁₁and A₁₂may not be linked (e.g., bonded) to each other,

when a12 is zero, A₁₂and A₁₃may not be linked (e.g., bonded) to each other,

when a13 is zero, A₁₃and A₁₄may not be linked (e.g., bonded) to each other,

R₁₁to R₁₈may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C₁-C₆₀alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀alkynyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀arylthio group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted C₁-C₆₀heteroaryloxy group, a substituted or unsubstituted C₁-C₆₀heteroarylthio 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), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁), —S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂),

R₁₆and R₁₁, or R₁₇and R₁₄may optionally be linked (e.g., coupled) to form a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀heterocyclic group,

R₁₄and R₁₅, or R₁₅and R₁₆may optionally be linked (e.g., coupled) to form a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀heterocyclic group,

R₁₇and R₁₁, R₁₇and R₁₂, or R₁₇and R₁₃may optionally be linked (e.g., coupled) to form a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀heterocyclic group,

b11 to b16 may each independently be selected from 1, 2, 3, 4, 5, 6, 7, and 8,

* and *′ may each indicate a binding site to a neighboring atom,

at least one substituent of the substituted C₅-C₆₀carbocyclic group, the substituted C₁-C₆₀heterocyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀aryl group, the substituted C₆-C₆₀aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from the group consisting of:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, and a C₁-C₆₀alkoxy group;

a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, and a C₁-C₆₀alkoxy group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁to Q₃, Q₁₁to Q₁₃, Q₂₁to Q₂₃, and Q₃₁to Q₃₃may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a C₁-C₆₀alkyl group substituted with at least one selected from deuterium, —F, and a cyano group; a C₆-C₆₀aryl group substituted with at least one selected from deuterium, —F, and a cyano group; a biphenyl group, and a terphenyl group.

One or more aspects of embodiments of the present disclosure provide an organic light-emitting device including: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, wherein the organic layer includes an emission layer and at least one species of the organometallic compound.

BRIEF DESCRIPTION OF THE DRAWING

These and/or other aspects of embodiments will become apparent and more readily appreciated from the following description of the example embodiments, taken in conjunction with the accompanying drawing, which is a schematic view of an organic light-emitting device according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

Reference will now be made in more detail to embodiments, examples of which are illustrated in the accompanying drawing, wherein like reference numerals refer to like elements throughout and duplicative descriptions thereof may not be provided. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the accompanying drawing, to explain aspects of embodiments of the present disclosure. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of” and “one of”, when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. An organometallic compound according to an embodiment of the present disclosure is represented by Formula 1:

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M₁₁in Formula 1 may be selected from platinum (Pt), palladium (Pd), copper (Cu), silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), and thulium (Tm).

In some embodiments, M₁₁may be selected from Pt, Pd, Cu, Ag, and Au.

For example, M₁₁may be Pt, but embodiments of the present disclosure are not limited thereto.

A₁₁to A₁₆in Formula 1 may each independently be selected from a C₅-C₆₀carbocyclic group and a C₁-C₆₀heterocyclic group.

In some embodiments, A₁₁to A₁₆may each independently be selected from a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a 1,2,3,4-tetrahydronaphthalene group, a furan group, a thiophene group, a silole group, an indene group, a fluorene group, an indole group, a carbazole group, a benzofuran group, a dibenzofuran group, a benzothiophene group, a dibenzothiophene group, a benzosilole group, a dibenzosilole group, an indeno pyridine group, an indolopyridine group, a benzofuropyridine group, a benzothienopyridine group, a benzosilolopyridine group, an indenopyrimidine group, an indolopyrimidine group, a benzofuropyrimidine group, a benzothienopyrimidine group, a benzosilolopyrimidine group, a dihydropyridine group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a 2,3-dihydroimidazole group, a triazole group, a 2,3-dihydrotriazole group, an oxazole group, an isoxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a 2,3-dihydrobenzimidazole group, an imidazopyridine group, a 2,3-dihydroimidazopyridine group, an imidazopyrimidine group, a 2,3-dihydroimidazopyrimidine group, an imidazopyrazine group, a 2,3-dihydroimidazopyrazine group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a 5,6,7,8-tetrahydroisoquinoline group, and a 5,6,7,8-tetrahydroquinoline group.

In some embodiments, A₁₁to A₁₃may each independently be represented by one of Formulae 2-1 to 2-43:

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In Formulae 2-1 to 2-43,

X₂₁to X₂₃may each independently be selected from C(R₂₄) and C—*, provided that at least two of X₂₁to X₂₃are C—*,

X₂₄may be N—*, and X₂₅and X₂₆may each independently be selected from C(R₂₄) and C—*, provided that at least one of X₂₅and X₂₆is C—*,

X₂₇and X₂₈may each independently be selected from N, N(R₂₅), and N—*, and X₂₉may be selected from C(R₂₄) and C—*, provided that i) at least one of X₂₇and X₂₈is N—*, and X₂₉is C—*, or ii) X₂₇and X₂₈are each N—*, and X₂₉is C(R₂₄),

R₂₁to R₂₄are each independently the same as described in connection with R₁₁in Formula 1,

b21 may be selected from 1, 2, and 3,

b22 may be selected from 1, 2, 3, 4, and 5,

b23 may be selected from 1, 2, 3, and 4,

b24 may be selected from 1 and 2, and

* indicates a binding site to a neighboring atom.

In one or more embodiments, A₁₄to A₁₆may each independently be represented by one of Formulae 2-1 to 2-4:

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In Formulae 2-1 to 2-4,

X₂₁to X₂₃may each independently be selected from C(R₂₄) and C—*, provided that at least two of X₂₁to X₂₃are C—*,

X₂₄may be N—*, and X₂₅and X₂₆may each independently be selected from C(R₂₄) and C—*, provided that at least one of X₂₅and X₂₆is C—*,

R₂₁to R₂₂are each independently the same as described in connection with R₁₁in Formula 1,

b21 may be selected from 1, 2, and 3, and

* may indicate a binding site to a neighboring atom.

In some embodiments, in Formula 1,

a moiety represented by

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may be a moiety represented by one of Formulae 1-1 to 1-64:

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In Formulae 1-1 to 1-64,

Y₁₄may be the same as described above, and

*, *′, and *″ may each indicate a binding site to a neighboring atom.

In one or more embodiments, in Formula 1,

a moiety represented by

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may be a moiety represented by one of Formulae 1-1, 1-3, and 1-10:

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In Formulae 1-1, 1-3, and 1-10,

Y₁₄may be the same as described above, and

*, *′, and *″ may each indicate a binding site to a neighboring atom.

In some embodiments, Y₁₁to Y₁₄in Formula 1 may each independently be N or C.

In some embodiments, Y₁₁, Y₁₂, and Y₁₃may each be C, and Y₁₄may be N;

Y₁₁, Y₁₂, and Y₁₄may each be C, and Y₁₃may be N;

Y₁₁, Y₁₃, and Y₁₄may each be C, and Y₁₂may be N;

Y₁₂, Y₁₃, and Y₁₄may each be C, and Y₁₁may be N;

Y₁₁and Y₁₄may each be C, and Y₁₂and Y₁₃may each be N;

Y₁₁and Y₁₄may each be N, and Y₁₂and Y₁₃may each be C;

Y₁₁and Y₁₂may each be C, and Y₁₃and Y₁₄may each be N;

Y₁₁and Y₁₂may each be N, and Y₁₃and Y₁₄may each be C;

Y₁₁and Y₁₃may each be C, and Y₁₂and Y₁₄may each be N; or

Y₁₁and Y₁₃may each be N, and Y₁₂and Y₁₄may each be C.

In some embodiments, T₁₁to T₁₄in Formula 1 may each independently be selected from a single bond, *—O—*′, and *—S—*′.

In some embodiments, T₁₁to T₁₄may each be a single bond at the same time (e.g., concurrently or simultaneously);

T₁₁may be selected from *—O—*′ and *—S—*′, and T₁₂to T₁₄may each independently be a single bond;

T₁₂may be selected from *—O—*′ and *—S—*′, and T₁₁, T₁₃, and T₁₄may each independently be a single bond;

T₁₃may be selected from *—O—*′ and *—S—*′, and T₁₁, T₁₂, and T₁₄may each independently be a single bond; or

T₁₄may be selected from *—O—*′ and *—S—*′, and T₁₁, T₁₂, and T₁₃may each independently be a single bond.

L₁₁to L₁₃in Formula 1 may each independently be selected from a single bond, *—O—*′, *—S—*′, *—C(R₁₇)(R₁₈)—*′, *—C(R₁₇)═*′, *═C(R₁₇)—*′, *—C(R₁₇)═C(R₁₈)—*′, *—C(═O)—*′, *—C(═S)—*′, *—C═C—*′, *—B(R₁₇)—*′, *—N(R₁₇)—*′, *—P(R₁₇)—*′, *—Si(R₁₇)(R₁₈)—*′, *—P(R₁₇)(R₁₈)—*′, and *—Ge(R₁₇)(R₁₈)—*′.

L₁₁to L₁₃may each independently be selected from a single bond, *—O—*′, *—S—*′, *—C(R₁₇)(R₁₈)—*′, *—C(R₁₇)═*′, *═C(R₁₇)—*′, *—B(R₁₇)—*′, *—N(R₁₇)—*′, *—Si(R₁₇)(R₁₈)—*′, and *—P(R₁₇)(R₁₈)—*′.

In one or more embodiments, L₁₁may be *—N(R₁₇)—*′, *—C(R₁₇)(R₁₈)—*′, or *—Si(R₁₇)(R₁₈)—*′, and R₁₇and R₁₂may be linked (e.g., coupled) to form a substituted or unsubstituted C₁-C₆₀heterocyclic group,

L₁₂may be *—N(R₁₇)—*′, *—C(R₁₇)(R₁₈)—*′, or *—Si(R₁₇)(R₁₈)—*′, and R₁₇and R₁₃may be linked (e.g., coupled) to form a substituted or unsubstituted C₁-C₆₀heterocyclic group.

In Formula 1, a11 to a13 may each independently be selected from 0, 1, 2, and 3,

when a11 is zero, A₁₁and A₁₂may not be linked (e.g., coupled) to each other, when a12 is zero, A₁₂and A₁₃may not be linked (e.g., coupled) to each other, and when a13 is zero, A₁₃and A₁₄may not be linked (e.g., coupled) to each other.

In some embodiments, a11, a12, and a13 may each independently be selected from 1, 2, and 3;

when a11 is zero, a12 and a13 may each independently be selected from 0, 1, 2, and 3;

when a12 is zero, a11 and a13 may each independently be selected from 0, 1, 2, and 3; or

when a13 is zero, a11 and a12 may each independently be selected from 0, 1, 2, and 3.

In one or more embodiments, a11 may be 0, and a12 and a13 may each independently be selected from 1, 2, and 3;

when a12 is zero, a11 and a13 may each independently be selected from 1, 2, and 3; or

when a13 is zero, a11 and a12 may each independently be selected from 1, 2, and 3.

In some embodiments, a11 may be zero, but embodiments of the present disclosure are not limited thereto.

In Formula 1, R₁₁to R₁₈may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C₁-C₆₀alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀alkynyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀arylthio group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted C₁-C₆₀heteroaryloxy group, a substituted or unsubstituted C₁-C₆₀heteroarylthio 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), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁), —S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂),

b11 to b16 in Formula 1 may each independently be selected from 1, 2, 3, 4, 5, 6, 7, and 8.

In some embodiments, R₁₁to R₁₈may each independently be selected from the group consisting of:

hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀alkyl group, and a C₁-C₂₀alkoxy group;

a C₁-C₂₀alkyl group and a C₁-C₂₀alkoxy group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a cyano group, a phenyl group, and a biphenyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentacenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, a silolyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an indolyl group, an isoindolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzosilolyl group, a benzothiazolyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, a thiadiazolyl group, an oxadiazolyl group, a triazinyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a benzocarbazolyl group, a naphthobenzofuranyl group, a naphthobenzothiophenyl group, a naphthobenzosilolyl group, a dibenzocarbazolyl group, a dinaphthofuranyl group, a dinaphthothiophenyl group, a dinaphtho silolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an oxazolopyridinyl group, a thiazolopyridinyl group, a benzonaphthyridinyl group, an azafluorenyl group, an azaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azadibenzosilolyl group, an indeno pyrrolyl group, an indolopyrrolyl group, an indeno carbazolyl group, and an indolocarbazolyl group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentacenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, a silolyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an indolyl group, an isoindolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzosilolyl group, a benzothiazolyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, a thiadiazolyl group, an oxadiazolyl group, a triazinyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a benzocarbazolyl group, a naphthobenzofuranyl group, a naphthobenzothiophenyl group, a naphthobenzosilolyl group, a dibenzocarbazolyl group, a dinaphthofuranyl group, a dinaphthothiophenyl group, a dinaphtho silolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an oxazolopyridinyl group, a thiazolopyridinyl group, a benzonaphthyridinyl group, an azafluorenyl group, an azaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azadibenzosilolyl group, an indeno pyrrolyl group, an indolopyrrolyl group, an indeno carbazolyl group, an indolocarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)(Q₃₁), —S(═O)₂(Q₃₁), —P(═O)(Q₃₁)(Q₃₂), and —P(═S)(Q₃₁)(Q₃₂); and

—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁), —S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂), and

Q₁to Q₃and Q₃₁to Q₃₃may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀heteroaryl group, a C₁-C₆₀heteroaryloxy group, a C₁-C₆₀heteroarylthio group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a C₁-C₆₀alkyl group substituted with at least one selected from deuterium, —F, and a cyano group; a C₆-C₆₀aryl group substituted with at least one selected from deuterium, —F, and a cyano group; a biphenyl group, and a terphenyl group.

For example, R₁₁to R₁₈may each independently be selected from the group consisting of:

hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group;

a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, and a cyano group; and

a phenyl group, a naphthyl group, and a pyridinyl group, but embodiments of the present disclosure are not limited thereto.

In Formula 1, * and *′ may each independently indicate a binding site to a neighboring atom.

At least one substituent of the substituted C₅-C₆₀carbocyclic group, the substituted C₁-C₆₀heterocyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀aryl group, the substituted C₆-C₆₀aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from the group consisting of:

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

In some embodiments, the organometallic compound may be represented by Formula 3-1 or Formula 3-2:

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In Formulae 3-1 and 3-2,

M₁₁, A₁₁to A₁₃, Y₁₁to Y₁₄, T₁₁to T₁₄, L₁₁to L₁₃, a11 to a13, R₁₁to R₁₃, and b11 to b13 may each independently be the same as described herein,

Y₃₁to Y₃₇may each independently be N or C,

Y₄₁to Y₄₇may each independently be N or C,

R₃₁to R₃₃may each independently be the same as described in connection with R₁₄,

R₄₁to R₄₃may each independently be the same as described in connection with R₁₃,

b31, b32, b41, and b42 may each independently be 1 or 2, and

b33 and b43 may each independently be 1, 2, or 3.

In one or more embodiments, when the organometallic compound is represented by Formula 3-1, the organometallic compound may be represented by Formula 3-1-1 or 3-1-2:

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In Formulae 3-1-1 and 3-1-2,

M₁₁, A₁₁, A₁₂, Y₁₁to Y₁₄, Y₃₁to Y₃₇, T₁₁to T₁₄, L₁₁, L₁₃, a11, a13, R₁₁, R₁₂, R₃₁to R₃₃, b11, b12, and b31 to b33 are the same as described herein,

Y₅₁to Y₅₅may each independently be N or C,

Y₆₁to Y₆₇may each independently be N or C,

R₅₁, R₆₁, and R₆₂may each independently be the same as described in connection with R₁₃,

b51 may be 1, 2, 3, or 4,

b61 may be 1, 2, or 3, and

b62 may be 1, 2, 3, or 4.

In one or more embodiments, when the organometallic compound is a compound represented by Formula 3-1-1, A₁₂may be a group represented by

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R₁₂and b12 may each independently be the same as described herein, and * and *′ may each indicate a binding site to a neighboring atom.

In one or more embodiments, when the organometallic compound is a group represented by Formula 3-1-1, 3-1-2, or 3-2, a11 may be zero.

In some embodiments, the organometallic compound may be selected from Compounds 1 to 45, but embodiments of the present disclosure are not limited thereto:

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The organometallic compound represented by Formula 1 may include a moiety represented by

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Because of the structural characteristics arising from the way in which the aromatic rings (A₁₄, A₁₅, and A₁₆) constituting the moiety are condensed, the organometallic compound may have a feature of improved energy transfer (e.g., may promote energy transfer), improve luminescent efficiency, and implement high color purity when applied to an organic light-emitting device.

When the organometallic compound represented by Formula 1 has a rigid (or substantially rigid) structure due to the inclusion of the moiety, an organic light-emitting device including the organometallic compound may have high durability and a long lifespan.

The organometallic compound may emit green light or red light. For example, the organometallic compound may emit green light or red light (bottom-emission CIE_x,ycolor coordinates (0.14, 0.06 to 0.08)) having a maximum emission wavelength of about 500 nm to about 800 nm, for example, about 530 nm to about 750 nm, but embodiments of the present disclosure are not limited thereto. Therefore, the organometallic compound represented by Formula 1 may be suitably used for manufacturing an organic light-emitting device that emits deep green light and/or deep red light.

Suitable synthesis methods of the organometallic compound represented by Formula 1 may be recognized by those of ordinary skill in the art with reference to the Examples provided below.

At least one kind or species of the organometallic compound of Formula 1 may be used between a pair of electrodes in an organic light-emitting device. For example, the organometallic compound may be included in an emission layer. The organometallic compound included in the emission layer may act as a dopant.

Accordingly, provided is an organic light-emitting device including: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer, wherein the organic layer includes at least one organometallic cyclic compound represented by Formula 1.

The expression “(an organic layer) includes at least one organometallic compound” as used herein may include a case in which “(an organic layer) includes identical (e.g., substantially identical) compounds represented by Formula 1” (e.g., all molecules having the structure of Formula 1 are the same) as well as a case in which “(an organic layer) includes two or more different organometallic compounds (e.g., two or more compounds having different structures) 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 an 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 included in the same layer (for example, Compound 1 and Compound 2 may both be included in an emission layer), or in different layers (for example, Compound 1 may be included in an emission layer and Compound 2 may be included in an electron transport region).

According to one or more embodiments,

the first electrode of the organic light-emitting device may be an anode,

the second electrode of the organic light-emitting device may be a cathode,

the organic layer may further include a hole transport region between the first electrode and the emission layer, and an electron transport region between the emission layer and the second electrode,

the hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof, and

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

The term “organic layer” as used herein may refer to a single layer and/or a plurality of layers between the first electrode and the second electrode of the organic light-emitting device. The material included in the “organic layer” is not limited to being an organic material.

In one or more embodiments, the emission layer may include the organometallic compound represented by Formula 1, the emission layer may further include a host, and an amount of the host in the emission layer may be larger than an amount of the organometallic compound in the emission layer.

In some embodiments, for example, the host may include a carbazole-containing compound.

In some embodiments, the hole transport region may include an electron blocking layer, and the electron blocking layer may include the organometallic compound.

In some embodiments, the electron transport region may include a hole blocking layer, which may include the organometallic compound.

In some embodiments, the hole transport region may include a p-dopant having a lowest unoccupied molecular orbital (LUMO) energy level of about −3.5 eV.

In some embodiments, the electron transport region may include a hole blocking layer, and the hole blocking layer may include a phosphine oxide-containing compound and.or a silyl-containing compound.

DESCRIPTION OF THE ACCOMPANYING DRAWING

The accompanying drawing is a schematic view of an organic light-emitting device 10 according to an embodiment of the present disclosure. The organic light-emitting device 10 includes a first electrode 110, an organic layer 150, and a second electrode 190.

Hereinafter, the structure of the organic light-emitting device 10 according to an embodiment of the present disclosure and a method of manufacturing the organic light-emitting device 10 will be described in connection with the accompanying drawing.

First Electrode 110

In the accompanying drawing, a substrate may be under the first electrode 110 or above the second electrode 190. The substrate may be a glass substrate or a plastic substrate, each having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and/or water resistance.

The first electrode 110 may be formed by depositing and/or sputtering a material for forming the first electrode 110 on the substrate. When the first electrode 110 is an anode, the material for the first electrode may be selected from materials with a high work function in order to facilitate hole injection.

The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. When the first electrode 110 is a transmissive electrode, the material for forming the first electrode may be selected from indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), and any combination thereof, but embodiments of the present disclosure are not limited thereto. In one or more embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, a material for forming a first electrode may be selected from magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), and any combination thereof, but embodiments of the present disclosure are not limited thereto.

The first electrode 110 may have a single-layered structure, or a multi-layered structure including two or more layers. For example, the first electrode 110 may have a three-layered structure of ITO/Ag/ITO, but the structure of the first electrode 110 is not limited thereto.

Organic Layer 150

The organic layer 150 may be on the first electrode 110. The organic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport region between the first electrode 110 and the emission layer, and an electron transport region between the emission layer and the second electrode 190.

Hole Transport Region in Organic Layer 150

The hole transport region may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from a hole injection layer, a hole transport layer, an emission auxiliary layer, and an electron blocking layer.

For example, the hole transport region may have a single-layered structure including a single layer including a plurality of different materials, or a multi-layered structure having a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, wherein the constituting layers in each structure are sequentially stacked from the first electrode 110 in the stated order, but the structure of the hole transport region is not limited thereto.

The hole transport region may include at least one selected from m-MTDATA, TDATA, 2-TNATA, NPB(NPD), β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound represented by Formula 201, and a compound represented by Formula 202:

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In Formulae 201 and 202,

L₂₀₁to L₂₀₄may each independently be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

L₂₀₅may be selected from *—O—*′, *—S—*′, *—N(Q₂₀₁)—*′, a substituted or unsubstituted C₁-C₂₀alkylene group, a substituted or unsubstituted C₂-C₂₀alkenylene group, a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

xa1 to xa4 may each independently be an integer of 0 to 3,

xa5 may be an integer of 1 to 10, and

R₂₀₁to R₂₀₄and Q₂₀₁may each independently be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀arylthio group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group.

For example, in Formula 202, R₂₀₁and R₂₀₂may optionally be linked (e.g., coupled) via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group, and R₂₀₃and R₂₀₄may optionally be linked (e.g., coupled) via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group.

In one or more embodiments, in Formulae 201 and 202,

L₂₀₁to L₂₀₅may each independently be selected from the group consisting of:

a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an indacenylene group, an acenaphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a rubicenylene group, a coronenylene group, an ovalenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, and a pyridinylene group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C₁-C₁₀alkyl group, a phenyl group substituted with —F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and Q₃₁to Q₃₃may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

In one or more embodiments, xa1 to xa4 may each independently be 0, 1, or 2.

In one or more embodiments, xa5 may be 1, 2, 3, or 4.

In one or more embodiments, R₂₀₁to R₂₀₄and Q₂₀₁may each independently be selected from a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C₁-C₁₀alkyl group, a phenyl group substituted with —F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃) and —N(Q₃₁)(Q₃₂), and

Q₃₁to Q₃₃may each independently be the same as described above.

In one or more embodiments, in Formula 201, at least one of R₂₀₁to R₂₀₃may each independently be selected from the group consisting of:

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C₁-C₁₀alkyl group, a phenyl group substituted with —F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group,

but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, in Formula 202, i) R₂₀₁and R₂₀₂may be linked (e.g., coupled) via a single bond, and/or ii) R₂₀₃and R₂₀₄may be linked (e.g., coupled) via a single bond.

In one or more embodiments, in Formula 202, at least one of R₂₀₁to R₂₀₄may be selected from the group consisting of:

a carbazolyl group; and

a carbazolyl group substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C₁-C₁₀alkyl group, a phenyl group substituted with —F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group,

but embodiments of the present disclosure are not limited thereto.

The compound represented by Formula 201 may be represented by Formula 201A:

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In some embodiments, the compound represented by Formula 201 may be further represented by Formula 201A(1), but embodiments of the present disclosure are not limited thereto:

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In some embodiments, the compound represented by Formula 201 may be further represented by Formula 201A-1, but embodiments of the present disclosure are not limited thereto:

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In some embodiments, the compound represented by Formula 202 may be further represented by Formula 202A:

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In some embodiments, the compound represented by Formula 202 may be further represented by Formula 202A-1:

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In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

L₂₀₁to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂to R₂₀₄may each independently be the same as described above,

R₂₁₁and R₂₁₂may each independently be the same as described in connection with R₂₀₃, and

R₂₁₃to R₂₁₇may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C₁-C₁₀alkyl group, a phenyl group substituted with —F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group.

The hole transport region may include at least one compound selected from Compounds HT1 to HT39, but embodiments of the present disclosure are not limited thereto:

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The thickness of the hole transport region may be about 100 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When the hole transport region includes at least one of a hole injection layer and a hole transport layer, the thickness of the hole injection layer may be about 100 Å to about 9,000 Å, for example, about 100 Å to about 1,000 Å, and the thickness of the hole transport layer may be about 50 Å to about 2,000 Å, for example, about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within these ranges, suitable or satisfactory hole transporting characteristics may be obtained without a substantial increase in driving voltage.

The emission auxiliary layer may increase light-emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by an emission layer(e.g., by adjusting the optical resonance distance in the device to match the wavelength of light emitted from the emission layer), and the electron blocking layer may block or reduce the flow of electrons from an electron transport region. The emission auxiliary layer and the electron blocking layer may include the materials as described above.

p-Dopant

The hole transport region may further include, in addition to these 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 charge-generation material may be, for example, a p-dopant.

In some embodiments, the p-dopant may have a lowest unoccupied molecular (LUMO) energy level of −3.5 eV or less.

The p-dopant may include at least one selected from a quinone derivative, a metal oxide, and a cyano group-containing compound, but embodiments of the present disclosure are not limited thereto.

For example, the p-dopant may include at least one selected from the group consisting of:

a quinone derivative (such as tetracyanoquinodimethane (TCNQ) or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ));

a metal oxide (such as tungsten oxide or molybdenum oxide);

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

a compound represented by Formula 221,

but embodiments of the present disclosure are not limited thereto:

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In Formula 221,

R₂₂₁to R₂₂₃may each independently be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, wherein at least one of R₂₂₁to R₂₂₃has at least one substituent selected from a cyano group, —F, —Cl, —Br, —I, a C₁-C₂₀alkyl group substituted with —F, a C₁-C₂₀alkyl group substituted with —Cl, a C₁-C₂₀alkyl group substituted with Br, and a C₁-C₂₀alkyl group substituted with —I.

Emission Layer in Organic Layer 150

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, or a blue emission layer, according to a sub-pixel (e.g., corresponding to a group of sub-pixels). In one or more embodiments, the emission layer may have a stacked structure including two or more layers selected from a red emission layer, a green emission layer, and a blue emission layer, in which the two or more layers may contact each other or may be separated from each other. In one or more embodiments, the emission layer may include two or more materials selected from a red light-emitting material, a green light-emitting material, and a blue light-emitting material, in which the two or more materials are mixed with each other in a single layer to emit white light.

The emission layer may include a host and a dopant. The dopant may include at least one selected from a phosphorescent dopant and a fluorescent dopant.

An amount of the dopant in the emission layer 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 of the present disclosure are not limited thereto.

The 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 within this range, excellent light-emission characteristics may be obtained without a substantial increase in driving voltage.

Host in Emission Layer

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

[Ar₃₀₁]_xb11-[(L₃₀₁)_xb1-R₃₀₁]_xb21. Formula 301

In Formula 301,

Ar₃₀₁may be a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀heterocyclic group,

xb11 may be 1, 2, or 3,

L₃₀₁may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

xb1 may be an integer of 0 to 5,

R₃₀₁may be selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C₁-C₆₀alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀alkynyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀arylthio group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), —N(Q₃₀₁)(Q₃₀₂), —B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), and —P(═O)(Q₃₀₁)(Q₃₀₂),

xb21 may be an integer from 1 to 5,

Q₃₀₁to Q₃₀₃may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group, but embodiments of the present disclosure are not limited thereto.

In some embodiments, Ar₃₀₁in Formula 301 may be selected from the group consisting of:

a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, and a dibenzothiophene group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁to Q₃₃may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group, but embodiments of the present disclosure are not limited thereto.

When xb11 in Formula 301 is two or more, two or more Ar301(s) may be linked (e.g., coupled) via a single bond.

In one or more embodiments, the compound represented by Formula 301 may be further represented by Formula 301-1 or 301-2:

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In Formulae 301-1 and 301-2,

A₃₀₁to A₃₀₄may each independently be selected from a benzene group, a naphthalene group, a phenanthrene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a pyridine group, a pyrimidine group, an indene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, an indole group, a carbazole group, a benzocarbazole group, a dibenzocarbazole group, a furan group, a benzofuran group, a dibenzofuran group, a naphthofuran group, a benzonaphthofuran group, a dinaphthofuran group, a thiophene group, a benzothiophene group, a dibenzothiophene group, a naphthothiophene group, a benzonaphthothiophene group, and a dinaphthothiophene group,

X₃₀₁may be O, S, or N-[(L₃₀₄)_xb4-R₃₀₄],

R₃₁₁to R₃₁₄may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

xb22 and xb23 may each independently be 0, 1, or 2,

L₃₀₁, xb1, R₃₀₁, and Q₃₁to Q₃₃may each independently be the same as described above,

L₃₀₂to L₃₀₄may each independently be the same as described in connection with L₃₀₁,

xb2 to xb4 may each independently be the same as described in connection with xb1, and

R₃₀₂to R₃₀₄may each independently be the same as described in connection with R₃₀₁.

For example, in Formulae 301, 301-1, and 301-2, L₃₀₁to L₃₀₄may each independently be selected from the group consisting of:

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, a pyridinylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a thiadiazolylene group, an oxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a triazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzimidazolylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an imidazopyridinylene group, an imidazopyrimidinylene group, and an azacarbazolylene group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁to Q₃₃may each independently be the same as described above.

In some embodiments, in Formulae 301, 301-1, and 301-2, R₃₀₁to R₃₀₄may each independently be selected from the group consisting of:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁to Q₃₃may each independently be the same as described above.

In one or more embodiments, the host may include an alkaline earth metal complex. For example, the host may be selected from a Be complex (for example, Compound H55), an Mg complex, and a Zn complex.

The host may include at least one selected from 9,10-di(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), 9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55, but embodiments of the present disclosure are not limited thereto:

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In some embodiments, the host may include at least one selected from a silicon-containing compound (for example, BCPDS as used in the examples and/or the like) and a phosphine oxide-containing compound (for example, POPCPA as used in the examples and/or the like).

However, embodiments of the present disclosure are not limited thereto. In some embodiments, the host may include only one compound, or two or more different compounds (for example, BCPDS and/or POPCPA).

Phosphorescent Dopant Included in Emission Layer in Organic Layer 150

The phosphorescent dopant may include an organometallic compound represented by Formula 1.

Electron Transport Region in Organic Layer 150

The electron transport region may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The electron transport region may include at least one selected from a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, and an electron injection layer, but embodiments of the present disclosure are not limited thereto.

For example, the electron transport region may have an electron transport layer/electron injection layer structure, a hole blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, or a buffer layer/electron transport layer/electron injection layer structure, wherein the constituting layers in each structure are sequentially stacked on the emission layer. However, embodiments of the structure of the electron transport region are not limited thereto.

The electron transport region (for example, a buffer layer, a hole blocking layer, an electron control layer, and/or an electron transport layer in the electron transport region) may include a metal-free compound containing at least one π electron-depleted nitrogen-containing ring.

The term “π electron-depleted nitrogen-containing ring” as used herein may refer to a ring-forming moiety, and for example, may be a C₁-C₆₀heterocyclic group including at least one *—N═*′ moiety.

For example, the “π electron-depleted nitrogen-containing ring” may be i) a 5-membered to 7-membered heteromonocyclic group including at least one *—N═*′ moiety, ii) a heteropolycyclic group including two or more condensed 5-membered to 7-membered heteromonocyclic groups, wherein each 5-membered to 7-membered heteromonocyclic group includes at least one *—N═*′ moiety, or iii) a heteropolycyclic group in which at least one 5-membered to 7-membered heteromonocyclic group is condensed with at least one C₅-C₆₀carbocyclic group, wherein each 5-membered to 7-membered heteromonocyclic group includes at least one *—N═*′ moiety.

Non-limiting examples of the π electron-depleted nitrogen-containing ring may include an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, and an azacarbazole group, but embodiments of the present disclosure are not limited thereto.

For example, the electron transport region may include a compound represented by Formula 601:

[Ar₆₀₁]_xe11-[(L₆₀₁)_xe1-R₆₀₁]_xe21. Formula 601

In Formula 601,

Ar₆₀₁may be a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀heterocyclic group,

xe11 may be 1, 2, or 3,

L₆₀₁may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

xe1 may be an integer from 0 to 5,

R₆₀₁may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀arylthio group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃), —C(═O)(Q₆₀₁), —S(═O)₂(Q₆₀₁), and —P(═O)(Q₆₀₁)(Q₆₀₂), Q₆₀₁to Q₆₀₃may each independently be a C₁-C₁₀alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group, and

xe21 may be an integer from 1 to 5.

In some embodiments, at least one Ar₆₀₁group and R₆₀₁group (among the total number of groups provided by xe11 and xe21, respectively) may include the π electron-depleted nitrogen-containing ring described above.

In some embodiments, in Formula 601, ring Ar₆₀₁may be selected from the group consisting of:

a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, and an azacarbazole group; and

Q₃₁to Q₃₃may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

When xe11 in Formula 601 is two or more, two or more Ar601(s) may be linked (e.g., coupled) via a single bond.

In one or more embodiments, Ar₆₀₁in Formula 601 may be an anthracene group.

In one or more embodiments, a compound represented by Formula 601 may be further represented by Formula 601-1:

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In Formula 601-1,

X₆₁₄may be N or C(R₆₁₄), X₆₁₅may be N or C(R₆₁₅), and X₆₁₆may be N or C(R₆₁₆), wherein at least one of X₆₁₄to X₆₁₆may be N,

L₆₁₁to L₆₁₃may each independently be the same as described in connection with L₆₀₁,

xe611 to xe613 may each independently be the same as described in connection with xe1,

R₆₁₁to R₆₁₃may each independently be the same as described in connection with R₆₀₁, and

R₆₁₄to R₆₁₆may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

In some embodiments, in Formulae 601 and 601-1, L₆₀₁and L₆₁₁to L₆₁₃may each independently be selected from the group consisting of:

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, a pyridinylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a thiadiazolylene group, an oxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a triazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzimidazolylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an imidazopyridinylene group, an imidazopyrimidinylene group, and an azacarbazolylene group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group, but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, xe1 and xe611 to xe613 in Formulae 601 and 601-1 may each independently be 0, 1, or 2.

In one or more embodiments, in Formulae 601 and 601-1, R₆₀₁and R₆₁₁to R₆₁₃may each independently be selected from the group consisting of:

—S(═O)₂(Q₆₀₁) and —P(═O)(Q₆₀₁)(Q₆₀₂), and

Q₆₀₁and Q₆₀₂may each independently be the same as described above.

The electron transport region may include at least one compound selected from Compounds ET1 to ET36, but embodiments of the present disclosure are not limited thereto:

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In one or more embodiments, the electron transport region may include at least one compound selected from 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq3, BAlq, 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole (TAZ), and NTAZ:

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In some embodiments, the electron transport region may include a phosphine oxide-containing compound (for example, TSPO1 as used in the examples and/or the like), but embodiments of the present disclosure are not limited thereto. In some embodiments, the phosphine oxide-containing compound may be used in a hole blocking layer in the electron transport region, but embodiments of the present disclosure are not limited thereto.

The thicknesses of the buffer layer, the hole blocking layer, or the electron control layer may each independently be about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. When the thicknesses of the buffer layer, the hole blocking layer, and/or the electron control layer are within these ranges, the electron blocking layer may have excellent electron blocking characteristics and/or electron control characteristics without a substantial increase in driving voltage.

The 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 within the range described above, the electron transport layer may have suitable or satisfactory electron transport characteristics without a substantial increase in driving voltage.

The electron transport region (for example, the electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.

The metal-containing material may include at least one selected from an alkali metal complex and an alkaline earth-metal complex. The alkali metal complex may include a metal ion selected from a lithium (Li) ion, a sodium (Na) ion, a potassium (K) ion, a rubidium (Rb) ion, and a cesium (Cs) ion, and the alkaline earth-metal complex may include a metal ion selected from a beryllium (Be) ion, a magnesium (Mg) ion, a calcium (Ca) ion, a strontium (Sr) ion, and a barium (Ba) ion. A ligand coordinated with the metal ion of the alkali metal complex or the alkaline earth-metal complex may be selected from a hydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, a hydroxy acridine, a hydroxy phenanthridine, a hydroxy phenyloxazole, a hydroxy phenylthiazole, a hydroxy diphenyloxadiazole, a hydroxy diphenylthiadiazole, a hydroxy phenylpyridine, a hydroxy phenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene, but embodiments of the present disclosure are not limited thereto.

For example, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate, LiQ) and/or Compound ET-D2:

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The electron transport region may include an electron injection layer that facilitates injection of electrons from the second electrode 190. The electron injection layer may directly contact the second electrode 190.

The electron injection layer may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combinations thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In some embodiments, the alkali metal may be Li, Na, or Cs. In one or more embodiments, the alkali metal may be Li or Cs, but embodiments of the present disclosure are not limited thereto.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare earth metal may be selected from scandium (Sc), yttrium (Y), cerium (Ce), terbium (Tb), ytterbium (Yb), and gadolinium (Gd).

The alkali metal compound, the alkaline earth-metal compound, and the rare earth metal compound may be selected from oxides and halides (for example, fluorides, chlorides, bromides, and/or iodides) of the alkali metal, the alkaline earth-metal, and the rare earth metal.

The alkali metal compound may be selected from alkali metal oxides (such as Li₂O, Cs₂O, and/or K₂O), and alkali metal halides (such as LiF, NaF, CsF, KF, LiI, NaI, CsI, and/or KI). In some embodiments, the alkali metal compound may be selected from LiF, Li₂O, NaF, LiI, NaI, CsI, and KI, but embodiments of the present disclosure are not limited thereto.

The alkaline earth-metal compound may be selected from alkaline earth-metal oxides (such as BaO, SrO, CaO, Ba_xSr_1-xO (0<x<1), and/or Ba_xCa_1-xO (0<x<1)).

In some embodiments, the alkaline earth-metal compound may be selected from BaO, SrO, and CaO, but embodiments of the present disclosure are not limited thereto.

The rare earth metal compound may be selected from YbF₃, ScF₃, ScO₃, Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In some embodiments, the rare earth metal compound may be selected from YbF3, ScF₃, TbF₃, YbI₃, ScI₃, and TbI₃, but embodiments of the present disclosure are not limited thereto.

The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include an alkali metal ion, alkaline earth-metal ion, and/or a rare earth metal ions described above, and a ligand coordinated with the metal ion of the alkali metal complex, the alkaline earth-metal complex, and/or the rare earth metal complex may be selected from hydroxy quinoline, hydroxy isoquinoline, hydroxy benzoquinoline, hydroxy acridine, hydroxy phenanthridine, hydroxy phenyloxazole, hydroxy phenylthiazole, hydroxy diphenyloxadiazole, hydroxy diphenylthiadiazole, hydroxy phenylpyridine, hydroxy phenylbenzimidazole, hydroxy phenylbenzothiazole, bipyridine, phenanthroline, and cyclopentadiene, but embodiments of the present disclosure are not limited thereto.

The electron injection layer may include (e.g., consist of) an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combination thereof, as described above. In one or more embodiments, the electron injection layer may further include an organic material. When the electron injection layer further includes an organic material, an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or combination thereof, that material may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.

The 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 within the range described above, the electron injection layer may have suitable or satisfactory electron injection characteristics without a substantial increase in driving voltage.

Second Electrode 190

The second electrode 190 may be on the organic layer 150 having the above-described structure. The second electrode 190 may be a cathode that is an electron injection electrode, and in this regard, the material for forming the second electrode 190 may be selected from a metal, an alloy, an electrically conductive compound, or a combination thereof, each having a relatively low work function.

The second electrode 190 may include at least one selected from lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), indium titanium oxide (ITO), and indium zinc oxide (IZO), but embodiments of the present disclosure are not limited thereto. The second electrode 190 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have a single-layered structure, or a multi-layered structure including two or more layers.

The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may be formed in a particular region or position using one or more suitable methods selected from vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, and laser-induced thermal imaging.

When each layer is formed by vacuum deposition, the deposition conditions may be selected depending on the compound 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 10⁻⁸torr to about 10⁻³torr, and a deposition rate of about 0.01 Å/sec to about 100 Å/sec.

When the layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region are formed by spin coating, the spin coating may be performed at a coating speed of about 2,000 rpm to about 5,000 rpm and at a heat treatment temperature of about 80° C. to about 200° C. depending on the material to be included in a layer to be formed, and the structure of the layer to be formed.

General Definition of Some of the Substituents

The term “C₁-C₆₀alkyl group” as used herein may refer to a linear or branched aliphatic saturated hydrocarbon monovalent group having 1 to 60 carbon atoms, and non-limiting examples thereof may 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, and a hexyl group. The term “C₁-C₆₀alkylene group” as used herein may refer to a divalent group having substantially the same structure as the C₁-C₆₀alkyl group.

The term “C₂-C₆₀alkenyl group” as used herein may refer to a hydrocarbon group having at least one carbon-carbon double bond at a main chain (e.g., in the middle) or at a terminus of the C₂-C₆₀alkyl group, and non-limiting examples thereof may include an ethenyl group, a propenyl group, and a butenyl group. The term “C₂-C₆₀alkenylene group” as used herein may refer to a divalent group having substantially the same structure as the C₂-C₆₀alkenyl group.

The term “C₂-C₆₀alkynyl group” as used herein may refer to a hydrocarbon group having at least one carbon-carbon triple bond at a main chain (e.g., in the middle) or at a terminus of the C₂-C₆₀alkyl group, and non-limiting examples thereof may include an ethynyl group and a propynyl group. The term “C₂-C₆₀alkynylene group” as used herein may refer to a divalent group having substantially the same structure as the C₂-C₆₀alkynyl group.

The term “C₁-C₆₀alkoxy group” as used herein may refer to a monovalent group represented by —OA₁₀₁(wherein A₁₀₁is a C₁-C₆₀alkyl group), and non-limiting examples thereof may include a methoxy group, an ethoxy group, and an isopropyloxy group.

The term “C₃-C₁₀cycloalkyl group” as used herein may refer to a monovalent saturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, and non-limiting examples thereof may include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term “C₃-C₁₀cycloalkylene group” as used herein may refer to a divalent group having substantially the same structure as the C₃-C₁₀cycloalkyl group.

The term “C₁-C₁₀heterocycloalkyl group” as used herein may refer to a monovalent monocyclic group having at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom and 1 to 10 carbon atoms, and non-limiting examples thereof may include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C₁-C₁₀heterocycloalkylene group” as used herein may refer to a divalent group having substantially the same structure as the C₁-C₁₀heterocycloalkyl group.

The term “C₃-C₁₀cycloalkenyl group” as used herein may refer to a monovalent monocyclic group having 3 to 10 carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity (e.g., the C₃-C₁₀cycloalkenyl group is not aromatic), and non-limiting examples thereof may include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C₃-C₁₀cycloalkenylene group” as used herein may refer to a divalent group having substantially the same structure as the C₃-C₁₀cycloalkenyl group.

The term “C₁-C₁₀heterocycloalkenyl group” as used herein may refer to a monovalent monocyclic group that has at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms, and at least one carbon-carbon double bond in its ring. Non-limiting examples of the C₁-C₁₀heterocycloalkenyl group may include a 4,5-dihydro-1,2,3,4-oxatriazolylgroup, a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C₁-C₁₀heterocycloalkenylene group” as used herein may refer to a divalent group having substantially the same structure as the C₁-C₁₀heterocycloalkenyl group.

The term “C₆-C₆₀aryl group” as used herein may refer to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and the term “C₆-C₆₀arylene group” as used herein may refer to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Non-limiting examples of the C₆-C₆₀aryl group may include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. When the C₆-C₆₀aryl group and the C₆-C₆₀arylene group each include two or more rings, the rings may be fused to each other.

The term “C₁-C₆₀heteroaryl group” as used herein may refer to a monovalent group having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, in addition to 1 to 60 carbon atoms. The term “C₁-C₆₀heteroarylene group” as used herein may refer to a divalent group having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, in addition to 1 to 60 carbon atoms. Non-limiting examples of the C₁-C₆₀heteroaryl group may include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C₁-C₆₀heteroaryl group and the C₁-C₆₀heteroarylene group each include two or more rings, the rings may be condensed with (e.g., fused to) each other.

The term “C₆-C₆₀aryloxy group” as used herein may refer to —OA₁₀₂(wherein A₁₀₂is a C₆-C₆₀aryl group), and the term “C₆-C₆₀arylthio group” as used herein may refer to —SA₁₀₃(wherein A₁₀₃is a C₆-C₆₀aryl group). The term “C₁-C₆₀heteroaryloxy group” as used herein may refer to —OA₁₀₄(wherein A₁₀₄is a C₁-C₆₀heteroaryl group), and the term “C₁-C₆₀heteroarylthio group” as used herein may refer to —SA₁₀₅(wherein A₁₀₅is a C₁-C₆₀heteroaryl group).

The term “monovalent non-aromatic condensed polycyclic group” as used herein may refer to a monovalent group (for example, having 8 to 60 carbon atoms) having two or more rings condensed with each other, only carbon atoms as ring-forming atoms, and no aromaticity in its entire molecular structure (e.g., the entire molecule is not aromatic). A non-limiting example of the monovalent non-aromatic condensed polycyclic group may be a fluorenyl group. The term “divalent non-aromatic condensed polycyclic group” as used herein may refer to a divalent group having substantially the same structure as the monovalent non-aromatic condensed polycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein may refer to a monovalent group (for example, having 1 to 60 carbon atoms) having two or more rings condensed to each other, at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, and no aromaticity in its entire molecular structure (e.g., the entire molecule is not aromatic). A non-limiting example of the monovalent non-aromatic condensed heteropolycyclic group may be a carbazolyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein may refer to a divalent group having substantially the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

The term “C₅-C₆₀carbocyclic group” as used herein may refer to a monocyclic or polycyclic group having 5 to 60 carbon atoms in which a ring-forming atom is a carbon atom only. The C₅-C₆₀carbocyclic group may be an aromatic carbocyclic group or a non-aromatic carbocyclic group. The C₅-C₆₀carbocyclic group may be a ring (such as benzene group), a monovalent group (such as a phenyl group), or a divalent group (such as a phenylene group). In one or more embodiments, depending on the number of substituents connected to the C₅-C₆₀carbocyclic group, the C₅-C₆₀carbocyclic group may be a trivalent group or a quadrivalent group.

The term “C₁-C₆₀heterocyclic group” as used herein may refer to a group having substantially the same structure as the C₅-C₆₀carbocyclic group, except that as a ring-forming atom, at least one heteroatom selected from N, O, Si, P, and S is used in addition to carbon (the number of carbon atoms may be in a range of 1 to 60).

At least one substituent of the substituted C₅-C₆₀carbocyclic group, the substituted C₁-C₆₀heterocyclic group, the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, the substituted divalent non-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀aryl group, the substituted C₆-C₆₀aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from the group consisting of:

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁₁to Q₁₃, Q₂₁to Q₂₃, and Q₃₁to Q₃₃may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a C₁-C₆₀alkyl group substituted with at least one selected from deuterium, —F, and a cyano group; a C₆-C₆₀aryl group substituted with at least one selected from deuterium, —F, and a cyano group; a biphenyl group, and a terphenyl group.

The term “Ph” as used herein may represent a phenyl group, the term “Me” as used herein may represent a methyl group, the term “Et” as used herein may represent an ethyl group, the term “ter-Bu” or “Bu^t,” as used herein, may represent a tert-butyl group, and the term “OMe” as used herein may represent a methoxy group.

The term “biphenyl group” as used herein may refer to a “phenyl group substituted with a phenyl group”. A “biphenyl group” is an example of “a substituted phenyl group” including a “C₆-C₆₀aryl group” (specifically, a phenyl group) as a substituent.

The term “terphenyl group” as used herein may refer to a “phenyl group substituted with a biphenyl group”. A “terphenyl group” is an example of a “phenyl group” including a “C₆-C₆₀aryl group substituted with a C₆-C₆₀aryl group” (specifically, a phenyl group substituted with a phenyl group) as a substituent.

* and *′ used herein, unless defined otherwise, may each refer to a binding site to a neighboring atom in a corresponding formula.

Hereinafter, a compound according to embodiments of the present disclosure and an organic light-emitting device according to embodiments of the present disclosure will be described in more detail with reference to Synthesis Examples and Examples. The expression “B was used instead of A” used in describing the Synthesis Examples means that an identical number of molar equivalents of A was used in place of molar equivalents of B.

SYNTHESIS EXAMPLES
Synthesis Example 1: Synthesis of Compound 1

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1) Synthesis of Intermediate [1-A]

2-methoxy-9H-carbazole (1.0 eq), 2-iodopyridine (1.2 eq), Pd₂(dba)₃(0.05 eq), SPhos (0.10 eq), and K₂CO₃(1.0 eq) were dissolved in toluene (0.1 M) and stirred at a temperature of 120° C. for 18 hours. After the reaction mixture was cooled to room temperature, an organic layer was extracted therefrom three times using dichloromethane and water. The extracted organic layer was dried over magnesium sulfate and concentrated, and column chromatography was performed thereon to obtain Intermediate [1-A] (yield: 91%).

2) Synthesis of Intermediate [1-B]

Compound [1-A] (1.0 eq) was dissolved in dichloromethane (0.1 M) and stirred at a temperature of −78° C., and boron tribromide solution (1.0 M in hexane, 2.0 eq) was slowly added thereto and stirred for 2 hours. The reaction mixture was neutralized using sodium bicarbonate aqueous solution, and an organic layer was extracted therefrom three times using ethyl acetate and water. The extracted organic layer was dried over magnesium sulfate and concentrated to obtain Intermediate [1-B] (yield: 64%).

3) Synthesis of Intermediate [1-C]

2-bromo-4H-benzo[def]carbazole (1.0 eq), 2-iodopyridine (1.2 eq), Pd₂(dba)₃(0.05 eq), SPhos (0.10 eq), and K₂CO₃(1.0 eq) were dissolved in toluene (0.1 M) and stirred at a temperature of 120° C. for 18 hours. After the reaction mixture was cooled to room temperature, an organic layer was extracted therefrom three times using dichloromethane and water. The extracted organic layer was dried over magnesium sulfate and concentrated, and column chromatography was performed thereon to obtain Intermediate [1-C] (yield: 93%).

4) Synthesis of Intermediate [1-D]

Compound [1-B] (1.0 eq), Compound [1-C] (1.2 eq), CuI (0.02 eq), K₂CO₃(2.0 eq), and L-Proline (0.04 eq) were dissolved in dimethyl sulfoxide (0.1M) and stirred at a temperature of 160° C. for 48 hours. After the reaction mixture was cooled to room temperature, an organic layer was extracted therefrom three times using dichloromethane and water. The extracted organic layer was dried over magnesium sulfate and concentrated, and column chromatography was performed thereon to obtain Intermediate [1-D] (yield: 44%).

5) Synthesis of Compound 1

Compound [1-D] (1.0 eq), potassium tetrachloroplatinate (K₂PtCl₄) (1.1 eq), and tetrabutylammonium bromide (0.1 eq) were dissolved in acetic acid (0.1M) and stirred at a temperature of 120° C. for 72 hours. After the reaction mixture was cooled to room temperature, an organic layer was extracted therefrom three times using dichloromethane and water. The extracted organic layer was dried over magnesium sulfate and concentrated, and column chromatography was performed thereon to obtain Compound 1 (yield: 31%).

Synthesis Example 2: Synthesis of Compound 11

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1) Synthesis of Intermediate [11-A]

3-bromo iodobenzene (1.0 eq), 1H-imidazole (1.2 eq), CuI (0.02 eq), K₂CO₃(2.0 eq), and L-Proline (0.04 eq) were dissolved in dimethylsulfonate (0.1M) and stirred at a temperature of 130° C. for 12 hours. After the reaction mixture was cooled to room temperature, an organic layer was extracted therefrom three times using dichloromethane and water. The extracted organic layer was dried over magnesium sulfate and concentrated, and column chromatography was performed thereon to obtain Intermediate [11-A] (yield: 65%).

2) Synthesis of Intermediate [11-B]

Intermediate [11-B] (yield: 32%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [1-D], except that Intermediate [11-A] was used instead of Intermediate [1-C], and Intermediate [41-B] as described in Synthesis Example 5 was used instead of Intermediate [1-B].

3) Synthesis of Intermediate [11-C]

Compound [11-B] (1.0 eq) and iodomethane (1.5 eq) were dissolved in tetrahydrofuran (0.1 M) and stirred at a temperature of 70° C. for 12 hours. After the reaction mixture was cooled to room temperature, a solvent was removed therefrom. The resultant mixture was filtered and washed using diethyl ether to obtain Intermediate [11-C] (yield: 85%).

4) Synthesis of Compound 11

Compound [11-C] (1.0 eq), dichloro(1,5-cyclooctadienyl) platinum(II) (1.05 eq), and sodium acetate (3.0 eq) were dissolved in tetrahydrofuran (0.1 M) and stirred at a temperature of 120° C. in a nitrogen atmosphere for 72 hours. The reaction mixture was cooled to room temperature and depressurized to remove a solvent therefrom. The concentrated reaction mixture was dissolved in dichloromethane, and a remaining precipitate was filtered. A filtrate was purified by column chromatography to obtain Compound 11 (yield: 35%).

Synthesis Example 3: Synthesis of Compound 21

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1) Synthesis of Intermediate [21-A]

Intermediate [21-A] (yield: 57%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [11-A], except that benzimidazole was used instead of 1H-imidazole.

2) Synthesis of Intermediate [21-B]

Intermediate [21-B] (yield: 31%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [1-D], except that Intermediate [21-A] was used instead of Intermediate [1-C], and Intermediate [41-B] as described in Synthesis Example 5 was used instead of Intermediate [1-B].

3) Synthesis of Intermediate [21-C]

Intermediate [21-C] (yield: 84%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [11-C], except that Intermediate [21-B] was used instead of Intermediate [11-B].

4) Synthesis of Compound 21

Synthesis 21 (yield: 28%) was synthesized in substantially the same manner as in the Synthesis of Compound 11, except that Intermediate [21-C] was used instead of Intermediate [11-C].

Synthesis Example 4: Synthesis of Compound 31

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1) Synthesis of Intermediate [31-A]

Intermediate [31-A] (yield: 86%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [1-A], except that 3-methoxy-5H-pyrrolo[3,2-b:4,5-b′]dipyridine was used instead of 2-methoxy-9H-carbazole.

2) Synthesis of Intermediate [31-B]

Intermediate [31-B] (yield: 68%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [1-B], except that Intermediate [31-A] was used instead of Intermediate [1-A].

3) Synthesis of Intermediate [31-C]

Intermediate [31-C] (yield: 24%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [1-D], except that Intermediate [31-B] was used instead of Intermediate [1-B].

4) Synthesis of Compound 31

Compound 31 (yield: 37%) was synthesized in substantially the same manner as in the Synthesis of Compound 1, except that Intermediate [31-C] was used instead of Intermediate [1-D].

Synthesis Example 5: Synthesis of Compound 41

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1) Synthesis of Intermediate [41-A]

Intermediate [41-A] (yield: 88%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [1-A], except that 2-methoxy-4H-benzo[def]carbazole was used instead of 2-methoxy-9H-carbazole.

2) Synthesis of Intermediate [41-B]

Intermediate [41-B] (yield: 66%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [1-B], except that Intermediate [41-A] was used instead of Intermediate [1-A].

3) Synthesis of Intermediate [31-C]

Intermediate [31-C] (yield: 31%) was synthesized in substantially the same manner as in the Synthesis of Intermediate [1-D], except that Intermediate [41-B] was used instead of Intermediate [1-B].

4) Synthesis of Compound 31

Compound 31 (yield: 33%) was synthesized in substantially the same manner as in the Synthesis of Compound 1, except that Intermediate [41-C] was used instead of Intermediate [1-D].

EXAMPLES
Example 1

As an anode, a Corning 15 Ω/cm²(1,200 Å) ITO glass substrate was cut to a size of 50 mm×50 mm×0.7 mm, sonicated with isopropyl alcohol and pure water for 5 minutes each, and then cleaned by exposure to ultraviolet rays and ozone for 30 minutes. Then, the ITO glass substrate was provided to a vacuum deposition apparatus. Compound 2-TNATA was vacuum-deposited on the ITO glass substrate to form a hole injection layer having a thickness of 600 Å, and 4,4′-bis[N-(1-naphthyl)-N-phenyl aminobiphenyl (NPB) (hole transport compound) was vacuum-deposited on the hole injection layer to form a hole transport layer having a thickness of 300 Å. 3,3-di(9H-carbazol-9-yl)biphenyl (mCBP) (host) and Compound 1 (dopant) were co-deposited on the hole transport layer in a ratio of 10% dopant (e.g., and 90% host) to form a green phosphorescent emission layer having a thickness of 300 Å. Then, diphenyl(4-(triphenylsilyl)phenyl)-phosphine oxide (TSPO1) was vacuum-deposited on the emission layer to form a hole blocking layer having a thickness of 50 Å. Then, Alq₃was deposited on the hole blocking layer to form an electron transport layer having a thickness of 300 Å. LiF, which is an alkali metal halide, was 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 electrode having a thickness of 3,000 Å, thereby forming a LiF/Al electrode. In this manner, an organic light-emitting device was manufactured.

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Examples 2 to 5 and Comparative Examples 1 to 4

Additional organic light-emitting devices were manufactured in each the same manner as in Example 1, except that the Compounds shown in Table 1 were used instead of Compound 1 as a dopant in forming each an emission layer.

Evaluation Example 1

The driving voltage, current density, luminance, luminescent efficiency, and maximum emission wavelength of the organic light-emitting devices manufactured according to Examples 1 to 5 and Comparative Examples 1 to 4 were measured using a Keithley SMU 236 and a luminance meter PR650 (Tektronix, Inc., Beaverton, Oreg.), and results thereof are shown in Table 1.

TABLE 1

Driving
Current

Emission
Lifespan

Emission
voltage
density
Luminance
Efficiency
Emission
wavelength
(RT_80%@ J =

layer
(V)
(mA/cm²)
(cd/m²)
(cd/A)
color
(nm)
40 mA/cm²) (hr)

Example
Compound
5.11
50
4125
8.25
Green
532
360

1
1

Example
Compound
5.17
50
4025
8.05
Green
529
327

2
11

Example
Compound
5.15
50
4033
8.07
Green
535
348

3
21

Example
Compound
5.20
50
4024
8.05
Green
533
351

4
31

Example
Compound
5.13
50
4055
8.11
Red
591
369

5
41

Comparative
Ir(ppy)₃
6.74
50
3870
7.74
Green
516
278

Example

1

Comparative
Compound
6.68
50
3790
7.58
Green
515
194

Example
46

2

Comparative
Compound
6.72
50
3535
7.07
Green
537
307

Example
47

3

Comparative
Compound
6.81
50
3325
6.65
Red
592
312

Example
48

4

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Referring to Table 1, it is confirmed that the organic light-emitting devices of Examples 1 to 5 have a low driving voltage, high luminance, high luminescent efficiency, and a long lifespan, compared with the organic light-emitting devices of Comparative Examples 1 to 4.

An organic light-emitting device including the organometallic compound according to embodiments of the present disclosure may have a low driving voltage, high efficiency, high luminance, and a long lifespan.

As used herein, the terms “use”, “using”, and “used” may be considered synonymous with the terms “utilize”, “utilizing”, and “utilized”, respectively. Further, the use of “may” when describing embodiments of the present disclosure refers to “one or more embodiments of the present disclosure”.

As used herein, the terms “substantially”, “about”, and similar terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent deviations in measured or calculated values that would be recognized by those of ordinary skill in the art.

Also, any numerical range recited herein is intended to include all sub-ranges of the same numerical precision subsumed within the recited range. For example, a range of “1.0 to 10.0” is intended to include all subranges between (and including) the recited minimum value of 1.0 and the recited maximum value of 10.0, that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein and any minimum numerical limitation recited in this specification is intended to include all higher numerical limitations subsumed therein. Accordingly, Applicant reserves the right to amend this specification, including the claims, to expressly recite any sub-range subsumed within the ranges expressly recited herein.

It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments.

While one or more embodiments have been described with reference to the drawing, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims and equivalents thereof.

Number	Name	Date	Kind
9461261	Kim et al.	Oct 2016	B2
9673409	Li et al.	Jun 2017	B2
10975113	Chen et al.	Apr 2021	B2
11495754	Brooks et al.	Nov 2022	B2
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20080036373	Itoh et al.	Feb 2008	A1
20090039768	Igarashi et al.	Feb 2009	A1
20120223634	Xia et al.	Sep 2012	A1
20130168656	Tsai	Jul 2013	A1
20140364605	Li	Dec 2014	A1
20140371825	Anemian et al.	Dec 2014	A1
20150008419	Li	Jan 2015	A1
20150090963	Kim	Apr 2015	A1
20150133662	Ahn et al.	May 2015	A1
20150162552	Li et al.	Jun 2015	A1
20170040551	Hwang et al.	Feb 2017	A1
20170077411	Kim	Mar 2017	A1
20180362567	Hwang	Dec 2018	A1
20190367546	Li	Dec 2019	A1

Number	Date	Country
107325105	Nov 2017	CN
2014-239225	Dec 2014	JP
2015-527972	Sep 2015	JP
2017-515823	Jun 2017	JP
10-2015-0039485	Apr 2015	KR
10-2017-0003654	Jan 2017	KR
10-2017-0016155	Feb 2017	KR
WO-2013187689	Dec 2013	WO
WO 2015171627	Nov 2015	WO

Organometallic compound and organic light-emitting device including the same

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Entry
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