Organic light-emitting device

Korean Patent Application No. 10-2014-0083230, filed on Jul. 3, 2014, in the Korean Intellectual Property Office, and entitled: “Organic Light-Emitting Device,” is incorporated by reference herein in its entirety.

1. Field

Embodiments relate to an organic light-emitting device.

2. Description of the Related Art

Organic light emitting devices are self-emission devices that have wide viewing angles, high contrast ratios, short response times, and excellent brightness, driving voltage, and response speed characteristics, and produce full-color images.

The organic light-emitting device may include a first electrode disposed on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode, which are sequentially disposed 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, are recombined in the emission layer to produce excitons. These excitons change from an excited state to a ground state, thereby generating light.

Embodiments are directed to an organic light-emitting device.

One or more embodiments provide an organic light-emitting device including: a first electrode; a second electrode; and an organic layer that is disposed between the first electrode and the second electrode, wherein the organic layer includes at least one selected from first materials represented by Formula 1 and at least one selected from second materials represented by Formula 2 below:

wherein in Formulae 1 and 2,

X 21 is selected from an oxygen atom, a sulfur atom, and a selenium atom;

L 11 is selected from a substituted or unsubstituted C 6 -C 60 arylene group, a substituted or unsubstituted C 1 -C 60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group;

L 21 and L 22 are each independently selected from a substituted or unsubstituted C 1 -C 10 alkylene group, a substituted or unsubstituted silylene group, a substituted or unsubstituted C 6 -C 60 arylene group, a substituted or unsubstituted C 1 -C 60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group;

a11, a21, and a22 are each independently selected from 0 and 1;

R 11 , R 12 , R 21 , and R 22 are each independently selected from a substituted or unsubstituted C 6 -C 60 aryl group, a substituted or unsubstituted C 1 -C 60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group;

b11 and b12 are each independently selected from 1, 2, and 3;

R 13 and R 14 are each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C 1 -C 60 alkyl group, a substituted or unsubstituted C 1 -C 60 alkoxy group, a substituted or unsubstituted C 3 -C 10 cycloalkyl group, a substituted or unsubstituted C 6 -C 60 aryl group, a substituted or unsubstituted C 6 -C 60 aryloxy group, a substituted or unsubstituted C 1 -C 60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 1 )(Q 2 )(Q 3 );

b13 and b14 are each independently selected from 1, 2, 3, and 4;

Y 21 is selected from a substituted or unsubstituted C 6 -C 60 aryl ring and a substituted or unsubstituted C 1 -C 60 heteroaryl ring;

n21 is selected from 1, 2, and 3;

at least one of substituents of the substituted C 1 -C 10 alkylene group, the substituted silylene group, the substituted C 6 -C 60 arylene group, the substituted C 1 -C 60 heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, the substituted divalent non-aromatic condensed heteropolycyclic group, the substituted C 6 -C 60 aryl group, the substituted C 1 -C 60 heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, the substituted monovalent non-aromatic condensed heteropolycyclic group, the substituted C 1 -C 60 alkyl group, substituted C 1 -C 60 alkoxy group, the substituted C 3 -C 10 cycloalkyl group, the substituted C 6 -C 60 aryloxy group, the substituted C 6 -C 60 aryl ring, and the substituted C 1 -C 60 heteroaryl ring is selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group;

a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 11 )(Q 12 )(Q 13 );

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 2 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 10 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 21 )(Q 22 )(Q 23 ); and

—Si(Q 31 )(Q 32 )(Q 33 ),

wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently selected from a C 1 -C 60 alkyl group, a C 6 -C 60 aryl group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

Features will be apparent to those of skill in the art by describing in detail exemplary embodiments with reference to the attached drawing in which:

The FIGURE illustrates a schematic cross-sectional view of an organic light-emitting device according to an embodiment.

Example embodiments will now be described more fully hereinafter with reference to the accompanying drawing; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary implementations to those skilled in the art.

In the drawing figure, the dimensions of layers and regions may be exaggerated for clarity of illustration. Like reference numerals refer to like elements throughout.

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,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms“includes”, “including”, “comprises” and/or “comprising” used herein specify the presence of stated features or components, but do not preclude the presence or addition of one or more other features or components.

It will be understood that when a layer, region, or component is referred to as being “on” or “onto” another layer, region, or component, it may be directly or indirectly formed on the other layer, region, or component. F example, intervening layers, regions, or components may be present.

The expression “(an organic layer) includes at least one selected from first materials” used herein may be interpreted as a case in which “(an organic layer) includes identical first materials represented by Formula 1 or two or more different first materials represented by Formula 1.”

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

The FIGURE illustrates a schematic cross-sectional view of an organic light-emitting device 10 according to an embodiment. For example, the organic light-emitting device 10 may include a first electrode 110 , a second electrode 190 , and an organic layer 150 between the first electrode 110 and the second electrode 190 . In the FIGURE, a substrate may be additionally disposed under the first electrode 110 or above the second electrode 190 . The substrate may be a glass substrate or transparent plastic substrate, each with excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water repellency.

The first electrode 110 may be formed by depositing or sputtering a material for forming the first electrode on the substrate. When the first electrode 110 is an anode, the material for the first electrode 110 may be selected from materials with a high work function to facilitate hole injection. The first electrode 110 may be a reflective electrode or a transmissive electrode. The material for the first electrode 110 may be a transparent and highly conductive material, and examples of such a material may include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO 2 ), and zinc oxide (ZnO). When the first electrode 110 is a semi-transmissive electrode or a reflective electrode, as a material for forming the first electrode, at least one of magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag) may be used.

The first electrode 110 may have a single-layer structure, or a multi-layer 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.

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

The organic layer 150 may include at least one first material represented by Formula 1 and at least second material represented by Formula 2.

L 11 in Formula 1 may be selected from a substituted or unsubstituted C 6 -C 60 arylene group, a substituted or unsubstituted C 1 -C 60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group;

at least one substituent selected from the substituted C 6 -C 60 arylene group, the substituted C 1 -C 60 heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, and the substituted divalent non-aromatic condensed heteropolycyclic group may be selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group;

a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 11 )(Q 12 )(Q 13 );

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 2 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 21 )(Q 22 )(Q 23 ); and

—Si(Q 31 )(Q 32 )(Q 33 ),

wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently selected from a C 1 -C 60 alkyl group, a C 6 -C 60 aryl group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

For example, L 11 in Formula 1 may be selected from

a phenylenegroup, a naphthylene group, a phenanthrenylene group, an anthracenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a pyrrolylene group, a thiophenylene group, a furanylene group, an imidazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, an indolylene indolylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a benzofuranylene group, a benzothiophenylene group, a triazolylene group, a tetrazolylene group, a triazinylene group, a dibenzofuranylene group, and a dibenzothiophenylene group; and

a phenylene group, a naphthylene group, a phenanthrenylene group, an anthracenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a pyrrolylene group, a thiophenylene group, a furanylene group, an imidazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, an indolylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a benzofuranylene group, a benzothiophenylene group, a triazolylene group, tetrazolylene group, a triazinylene group, a dibenzofuranylene group, and a dibenzothiophenylene group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, acenaphthyl group, a fluorenyl group, a Spiro-fluorenyl 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, pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl 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 carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group, and an imidazopyridinyl group, but they are not limited thereto.

In some embodiments, L 11 in Formula 1 may be selected from:

a phenylene group, a naphthylene group, a pyridinylene group, a quinolinylene group, and an isoquinolinylene group; and

a phenylene group, a naphthylene group, a pyridinylene group, a quinolinylene group, and an isoquinolinylene group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a C 1 -C 20 alkyl group, a phenyl group, and a naphthyl group, but is not limited thereto.

In other embodiments, L 11 in Formula 1 may be a group selected from a phenylene group and a naphthylene group, but is not limited thereto:

According to other embodiments, L 11 in Formula 1 may be a group represented by one of Formulae 3-1 to 3-9 below, but is not limited thereto:

In Formulae 3-1 to 3-9, * and *′ indicate binding sites to a neighboring atom.

a11 in Formula 1 indicates the number of L 11 , and a11 may be selected from 0 and 1. when a11 is 0, (L 11 ) a11 is a single bond. For example, a11 in Formula 1 may be 0, but is not limited thereto.

R 11 and R 12 in Formula 1 may be each independently selected from a substituted or unsubstituted C 6 -C 60 aryl group, a substituted or unsubstituted C 1 -C 60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic hetero-condensed polycyclic group;

at least one substituent selected from the substituted C 6 -C 60 aryl group, the substituted C 1 -C 60 heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group;

a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q11)(Q12)(Q13);

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 2 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 1 ° heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 21 )(Q 22 )(Q 23 ); and

—Si(Q 31 )(Q 32 )(Q 33 ),

wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently selected from a C 1 -C 60 alkyl group, a C 6 -C 60 aryl group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

For example, R 11 and R 12 in Formula 1 may be each independently selected from

a phenyl 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-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, 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, a ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isoothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isooindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl 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 benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isoobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group group, a benzocarbazolyl group, and a dibenzocarbazolyl group; and

a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, acenaphthyl group, a fluorenyl group, a spiro-fluorenyl 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, pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl 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 benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 20 -C 20 alkyl group, a C 20 -C 20 alkoxy group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, acenaphthyl group, a fluorenyl group, a spiro-fluorenyl 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, pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group, but they are not limited thereto.

In some embodiments, R 11 and R 12 in Formula 1 may be each independently selected from

a phenyl group, a naphthyl group, a fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, and a chrysenyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, and a chrysenyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a C 1 -C 20 alkyl group, a phenyl group, and a naphthyl group, but they are not limited thereto.

In some embodiments, R 11 and R 12 in Formula 1 may be each independently selected from

a phenyl group, a naphthyl group, and a fluorenyl group; and

a phenyl group, a naphthyl group, and a fluorenyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a methyl group, a phenyl group, and a naphthyl group, but they are not limited thereto.

In other embodiments, R 11 and R 12 in Formula 1 may be each independently a group represented by one of Formulae 4-1 to 4-3 below, but they are not limited thereto.

Wherein, in Formulae 4-1 to 4-3,

Z 1 and Z 2 may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a methyl group, a phenyl group, and a naphthyl group;

d1 is selected from 1, 2, 3, 4, and 5;

d2 is selected from 1, 2, 3, 4, 5, 6, and 7; and

* indicates a binding site to a neighboring atom.

In other embodiments, R 11 and R 12 in Formula 1 may be each independently a group represented by one of Formulae 5-1 to 5-5 below, but they are not limited thereto:

wherein in Formulae 5-1 to 5-5, * indicates a binding site to a neighboring atom.

b11 in Formula 1 indicates the number of R 11 , and b11 may be selected from 1, 2, and 3. When b11 is 2 or more, a plurality of R 11 may be identical or different. For example, b11 in Formula 1 may be 1, but is not limited thereto.

b12 in Formula 1 indicates the number of R 12 , and b12 may be selected from 1, 2, and 3. When b12 is 2 or more, a plurality of R 12 may be identical or different. For example, b12 in Formula 1 may be 1, but is not limited thereto.

R 13 and R 14 in Formula 1 may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C 1 -C 60 alkyl group, a substituted or unsubstituted C 1 -C 60 alkoxy group, a substituted or unsubstituted C 3 -C 10 cycloalkyl group, a substituted or unsubstituted C 6 -C 60 aryl group, a substituted or unsubstituted C 6 -C 60 aryloxy group, a substituted or unsubstituted C 1 -C 60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 1 )(Q 2 )(Q 3 );

at least one substituent of the substituted C 6 -C 60 aryl group, substituted C 1 -C 60 heteroaryl group, substituted monovalent non-aromatic condensed polycyclic group, substituted monovalent non-aromatic condensed heteropolycyclic group, substituted C 1 -C 60 alkyl group, substituted C 1 -C 60 alkoxy group, substituted C 3 -C 10 cycloalkyl group, and substituted C 6 -C 60 aryloxy group may be selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group;

a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q11)(Q12)(Q13);

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 2 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 21 )(Q 22 )(Q 23 ); and

—Si(Q 31 )(Q 32 )(Q 33 ),

wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently selected from a C 1 -C 60 alkyl group, a C 6 -C 60 aryl group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

For example, R 13 and R 14 in Formula 1 may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a methyl group, an ethyl group, n-a propyl group, iso-a propyl group, an n-butyl group, a sec-butyl group, iso-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, acenaphthyl group, a fluorenyl group, a spiro-fluorenyl 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, pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl 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 benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group, but they are not limited thereto.

In some embodiments, R 13 and R 14 in Formula 1 may be each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, an iso-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, a phenyl group, a 1-naphthyl group, and a 2-naphthyl group, but they are not limited thereto.

b13 in Formula 1 indicates the number of R 13 , and b13 may be selected from 1, 2, 3, and 4. When b13 is 2 or more, a plurality of R 13 may be identical or different. For example, b13 in Formula 1 may be 1, but is not limited thereto.

b14 in Formula 1 indicates the number of R 14 , and b14 may be selected from 1, 2, 3, and 4. When b14 is 2 or more, a plurality of R 14 may be identical or different. For example, b14 in Formula 1 may be 1, but is not limited thereto.

L 21 and L 22 in Formula 2 may be each independently selected from a substituted or unsubstituted C 1 -C 10 alkylene group, a substituted or unsubstituted silylene group, a substituted or unsubstituted C 6 -C 60 arylene group, a substituted or unsubstituted C 1 -C 60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group;

at least one substituent selected from the substituted C 1 -C 10 alkylene group, the substituted silylene group, the substituted C 6 -C 60 arylene group, the substituted C 1 -C 60 heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, and the substituted divalent non-aromatic condensed heteropolycyclic group may be selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group;

a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 11 )(Q 12 )(Q 13 );

a C 3 -C 10 cycloalkyl group, a C 1 -C 20 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 2 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 20 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 21 )(Q 22 )(Q 23 ); and

—Si(Q 31 )(Q 32 )(Q 33 ),

wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently selected from a C 1 -C 60 alkyl group, a C 6 -C 60 aryl group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

In some embodiments, L 21 to L 22 in Formula 2 may be each independently selected from a methylene group, an ethylene group, a propylene group, a butylene group, a phenylene group, a naphthylene group, a phenanthrenylene group, an anthracenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a pyrrolylene group, a thiophenylene group, a furanylene group, an imidazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, an indolylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a benzofuranylene group, a benzothiophenylene group, a triazolylene group, a tetrazolylene group, a triazinylene group, a dibenzofuranylene group, and a dibenzothiophenylene group; and

a methylene group, an ethylene group, a propylene group, a butylene group, a phenylene group, a naphthylene group, a phenanthrenylene group, an anthracenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a pyrrolylene group, a thiophenylene group, a furanylene group, an imidazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, an indolylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a benzofuranylene group, a benzothiophenylene group, a triazolylene group, tetrazolylene group, a triazinylene group, a dibenzofuranylene group, and a dibenzothiophenylene group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, acenaphthyl group, a fluorenyl group, a spiro-fluorenyl 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, pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl 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 carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group, and an imidazopyridinyl group, but they are not limited thereto.

In some embodiments, L 21 and L 22 in Formula 2 may be each independently selected from a phenylene group, a naphthylene group, a pyridinylene group, a quinolinylene group, and an isoquinolinylene group; and

a phenylene group, a naphthylene group, a pyridinylene group, a quinolinylene group, and an isoquinolinylene group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a C 1 -C 20 alkyl group, a phenyl group, and a naphthyl group, but they are not limited thereto.

In other embodiments, L 21 and L 22 in Formula 2 may be each independently a group selected from a phenylene group and a naphthylene group, but they are not limited thereto:

In other embodiments, L 21 and L 22 in Formula 2 may be each independently a group selected from groups represented by one of Formulae 3-1 to 3-9 below, but they are not limited thereto:

wherein in Formulae 3-1 to 3-9, * and *′ indicate binding sites to a neighboring atom.

a21 in Formula 2 indicates the number of L 21 , and a21 may be selected from 0 and 1. When a21 is 0, (L 21 ) a21 is a single bond.

a22 in Formula 2 indicates the number of L 22 , and a22 may be selected from 0 and 1. When a22 is 0, (L 22 ) a22 is a single bond.

R 21 and R 22 in Formula 2 may be each independently selected from a substituted or unsubstituted C 6 -C 60 aryl group, a substituted or unsubstituted C 1 -C 60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic hetero-condensed polycyclic group;

at least one substituent selected from the substituted C 6 -C 60 aryl group, the substituted C 1 -C 60 heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 6 alkoxy group;

a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q11)(Q12)(Q13);

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 6 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 2 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 21 )(Q 22 )(Q 23 ); and

—Si(Q 31 )(Q 32 )(Q 33 ),

wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently selected from a C 1 -C 60 alkyl group, a C 6 -C 60 aryl group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

For example, R 21 and R 22 in Formula 2 may be each independently selected from a phenyl 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-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, 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, a ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isoothiazolyl group, a oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isooindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl 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 benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isoobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group group, a benzocarbazolyl group, and a dibenzocarbazolyl group; and

a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, acenaphthyl group, a fluorenyl group, a spiro-fluorenyl 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, pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl 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 benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 20 -C 20 alkyl group, a C 20 -C 20 alkoxy group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, acenaphthyl group, a fluorenyl group, a spiro-fluorenyl 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, pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isooxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzooxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group, but they are not limited thereto.

In other embodiments, R 21 and R 22 in Formula 2 are each independently selected from a phenyl group, a naphthyl group, a fluorenyl 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 pyridinyl group, a pyrazinyl group, a pyrimidinyl group, an indolyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl group, a benzoquinolinyl group, a phthalazinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a triazolyl group, a tetrazolyl group, a triazinyl group, a dibenzofuranyl group, and a dibenzothiophenyl group; and

a phenyl group, a naphthyl group, a fluorenyl 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 pyridinyl group, a pyrazinyl group, a pyrimidinyl group, an indolyl group, a quinolinyl group, an isoquinolinyl group, a carbazolyl group, a benzoquinolinyl group, a phthalazinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a triazolyl group, a tetrazolyl group, a triazinyl group, a dibenzofuranyl group, and a dibenzothiophenyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a C 1 -C 20 alkyl group, a phenyl group, and a naphthyl group, but they are not limited thereto.

In some embodiments, R 21 and R 22 in Formula 2 may be each independently selected from

a phenyl group, a naphthyl group, a fluorenyl group, a pyridinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, and a benzoimidazolyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a pyridinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, and a benzoimidazolyl group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a methyl group, a phenyl group, and a naphthyl group, but they are not limited thereto.

In other embodiments, R 21 and R 22 in Formula 2 may be each independently a group represented by one of Formulae 4-1 to 4-14 below, but they are not limited thereto:

wherein in Formulae 4-1 to 4-14,

Z 1 , Z 2 , and Z 3 are each independently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a methyl group, a phenyl group, and a naphthyl group;

d1 is selected from 1, 2, 3, 4, and 5;

d2 is selected from 1, 2, 3, 4, 5, 6, and 7;

d3 is selected from 1, 2, 3, and 4;

d4 is selected from 1, 2, and 3;

d5 is selected from 1 and 2; and

* indicates a binding site to a neighboring atom.

In other embodiments, R 21 and R 22 in Formula 2 may be each independently a group represented by one of Formulae 5-1 to 5-27 below, but they are not limited thereto:

wherein in Formulae 5-1 to 5-27,

Z 1 and Z 2 may be each independently selected from a hydrogen and a phenyl group;

* indicates a binding site to a neighboring atom.

X 21 in Formula 2 may be selected from an oxygen atom, a sulfur atom, and a selenium atom.

For example, X 21 in Formula 2 may be an oxygen atom, but is not limited thereto.

Y 21 in Formula 2 may be or may include a moiety selected from a substituted or unsubstituted C 6 -C 60 aryl ring and a substituted or unsubstituted C 1 -C 60 heteroaryl ring;

at least one substituent selected from the substituted C 6 -C 60 aryl ring and the substituted C 1 -C 60 heteroaryl ring may be selected from

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 6 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group;

a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 11 )(Q 12 )(Q 13 );

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 2 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C 1 -C 60 alkyl group, a C 1 -C 60 alkenyl group, a C 1 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 21 )(Q 22 )(Q 23 ); and

—Si(Q 31 )(Q 32 )(Q 33 ),

wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently selected from a C 1 -C 60 alkyl group, a C 6 -C 60 aryl group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

For example, Y 21 in Formula 2 may be or may include a C 1 -C 30 heteroaryl ring containing at least one nitrogen atom, but is not limited thereto.

According to other embodiments, Y 21 in Formula 2 may be or may include a moiety represented by one of Formulae 7-1 to 7-7 below, but is not limited thereto:

wherein in Formulae 7-1 to 7-7,

E 21 to E 25 may be each independently selected from

a benzene, a naphthalene, a phenanthrene, an anthracene, a triphenylene, a pyrrole, a thiophene, a furan, an imidazole, a benzoxazole, a benzothiazole, a benzoimidazole, a pyridine, a pyrazine, a pyrimidine, an indole, a quinoline, an isoquinoline, a benzoquinoline, a phenanthridine, an acridine, a phenanthroline, a benzofuran, a benzothiophene, a triazole, a tetrazole, a triazine, a dibenzofuran, and a dibenzothiophene; and

a benzene, a naphthalene, a phenanthrene, an anthracene, a triphenylene, a pyrrole, a thiophene, a furan, an imidazole, a benzoxazole, a benzothiazole, a benzoimidazole, a pyridine, a pyrazine, a pyrimidine, an indole, a quinoline, an isoquinoline, a benzoquinoline, a phenanthridine, an acridine, a phenanthroline, a benzofuran, a benzothiophene, a triazole, a tetrazole, a triazine, a dibenzofuran, and a dibenzothiophene, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl 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-fluorenyl 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 pyrrolyl group, a thiophenyl group, a furanyl 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 isoindolyl group, an indolyl group, an indazolyl group, a purinyl 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 carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group, and an imidazopyridinyl group.

According to other embodiments, Y 21 in Formula 2 may be or may include a moiety represented by one of Formulae 7-1 to 7-7 below, but is not limited thereto:

wherein in Formulae 7-1 to 7-7,

E 21 to E 25 may be each independently selected from

a benzene, a naphthalene, a phenanthrene, an anthracene, a triphenylene, a pyrrole, an imidazole, a benzoxazole, a benzothiazole, a benzoimidazole, a pyridine, a pyrazine, a pyrimidine, an indole, a quinoline, an isoquinoline, a benzoquinoline, a phenanthridine, an acridine, a phenanthroline, a triazole, a tetrazole, and a triazine; and

a benzene, a naphthalene, a phenanthrene, an anthracene, a triphenylene, a pyrrole, an imidazole, a benzoxazole, a benzothiazole, a benzoimidazole, a pyridine, a pyrazine, a pyrimidine, an indole, a quinoline, an isoquinoline, a benzoquinoline, a phenanthridine, an acridine, a phenanthroline, a triazole, a tetrazole, and a triazine, each substituted with at least one selected from a methyl group, a phenyl group, and a naphthyl group;

wherein E 21 in Formula 7-1, one selected from E 21 and E 22 in Formula 7-2, one selected from E 21 , E 22 , and E 23 in Formula 7-3, one selected from E 21 , E 22 , and E 23 in Formula 7-4, one selected from E 21 , E 22 , E 23 , and E 24 in Formula 7-5, one selected from E 21 , E 22 , E 23 , and E 24 in Formula 7-6, and one selected from E 21 , E 22 , E 23 , and E 24 in Formula 7-7 are each independently selected from a pyrrole, an imidazole, a benzoxazole, a benzothiazole, a benzoimidazole, a pyridine, a pyrazine, a pyrimidine, an indole, a quinoline, an isoquinoline, a benzoquinoline, a phenanthridine, an acridine, a phenanthroline, a triazole, a tetrazole, and a triazine.

According to other embodiments, Y 21 in Formula 2 may be or may include a moiety represented by one of Formulae 8-1 to 8-38 below, but is not limited thereto:

wherein, in Formulae 8-1 to 8-38,

E 21 to E 24 are each independently selected from or include a benzene, a naphthalene, a phenanthrene, an anthracene, a triphenylene, a pyrrole, an imidazole, a benzoimidazole, a pyridine, a pyrazine, a pyrimidine, an indole, a quinoline, an isoquinoline, a benzoquinoline, a phenanthridine, an acridine, a phenanthroline, a triazole, a tetrazole, and a triazine.

According to other embodiments, Y 21 in Formula 2 may be or may include a moiety represented by one of Formulae 8-1 to 8-38 below, but is not limited thereto:

wherein, in Formulae 8-1 to 8-38,

E 21 to E 24 may be each independently selected from a benzene, a naphthalene, a pyridine, a pyrazine, a pyrimidine, a quinoline, an isoquinoline, a phenanthridine, an acridine, and a phenanthroline.

In Formula 2, n21 indicates the number of moieties represented by

and n21 may be selected from 1, 2, and 3. For example, n21 in Formula 2 may be 1, but is not limited thereto. In some embodiments, n21 in Formula 2 may be 2, but is not limited thereto. When n21 is 1, Y 21 is a monovalent group. When n21 is 2, Y 21 is a divalent group. When n21 is 3, Y 21 is a trivalent group.

In some embodiments, the first material may be represented by one of Formulae 1A and 1B below, and the second material may be represented by one of Formulae 2A and 2B, below, but they are not limited thereto:

in Formulae 1A, 1B, 2A, and 2B,

L 11 , a11, R 11 to R 14 , b11 to b14 may be defined the same as described above;

X 21 , L 21 , L 22 , a21, a22, R 21 , R 22 , and Y 21 may be defined the same as described above;

X 22 may be defined the same as X 21 in Formula 2;

L 23 and L 24 may be each individually defined the same as L 21 in Formula 2;

a23 and a24 may be each individually defined the same as a21 in Formula 2; and

R 23 and R 24 may be each individually defined the same as R 21 in Formula 2;

In some embodiments, the first material may be represented by one of Formulae 1A-1, 1A-2, 1B-1, and 1B-2 below, and the second material may be represented by one of Formulae 2A-1 and 2B-1 below, but they are not limited thereto:

in Formulae 1A-1, 1A-2, 1B-1, 1B-2, 2A-1, and 2B-1,

R 11 to R 14 , b13, and b14 may be defined the same as described above;

L 21 , L 22 , a21, a22, R 21 , R 22 , and Y 21 may be defined the same as described above;

L 23 and L 24 may be each independently defined the same as L 21 in Formula 2;

a23 and a24 may be each independently defined the same as a21 in Formula 2; and

R 23 and R 24 may be each independently defined the same as R 21 in Formula 2;

In some embodiments, the first material may be selected from Compounds 100 to 201 below, and the second material may be selected from Compounds 201A to 276A, but they are not limited thereto:

The second material may contribute to a decrease in electron moving speed. Accordingly, in an organic light-emitting device including the first material and the second material, an emission layer may have high carrier balance. Thus, the organic light-emitting device including the first material and the second material may have high efficiency and a long lifespan.

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

The hole transport region may include at least one selected from a hole injection layer (HIL), a hole transport layer (HTL), a buffer layer (BL), and an electron blocking layer (EBL), and the electron transport region may include at least one selected from a buffer layer, an electron transport layer (ETL), and an electron injection layer (EIL), but is not limited thereto.

The hole transport region may have a single-layered structure formed of a single material, a single-layered structure formed of a plurality of different materials, or a multi-layered structure having a plurality of layers formed of a plurality of different materials.

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

When the hole transport region includes a hole injection layer, the hole injection layer may be formed on the first electrode 110 by using various methods, such as vacuum deposition, spin coating casting, a Langmuir-Blodgett (LB) method, ink-jet printing, laser-printing, or laser-induced thermal imaging.

When a hole injection layer is formed by vacuum deposition, e.g., the vacuum deposition may be performed at a temperature of a deposition temperature of about 100 to about 500° C., at a vacuum degree of about 10 −8 to about 10 −3 torr, and at a deposition rate of about 0.01 to about 100 Å/sec in consideration of a compound for a hole injection layer to be deposited, and the structure of a hole injection layer to be formed.

When a hole injection layer is formed by spin coating, the spin coating may be performed at a coating rate of about 2,000 rpm to about 5,000 rpm, and at a temperature of about 80° C. to 200° C. in consideration of a compound for a hole injection layer to be deposited, and the structure of a hole injection layer to be formed.

When the hole transport region includes a hole transport layer, the hole transport layer may be formed on the first electrode 110 or the hole injection layer by using various methods, such as vacuum deposition, spin coating, casting, a LB method, ink-jet printing, laser-printing, or laser-induced thermal imaging. When the hole transport layer is formed by vacuum deposition or spin coating, deposition and coating conditions for the hole transport layer may be determined by referring to the deposition and coating conditions for the hole injection layer.

The hole transport region may include at least one selected from m-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB, α-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 sulfonicacid (Pani/CSA), (polyaniline)/poly(4-styrenesulfonate) (PANI/PSS), a compound represented by Formula 201 below, and a compound represented by Formula 202 below:

wherein in Formulae 201 and 202,

L 201 to L 205 are each independently selected from a substituted or unsubstituted C 3 -C 10 cycloalkylene group, a substituted or unsubstituted C 3 -C 10 heterocycloalkylene group, a substituted or unsubstituted C 3 -C 10 cycloalkenylene group, a substituted or unsubstituted C 3 -C 10 heterocycloalkenylene group, a substituted or unsubstituted C 6 -C 60 arylene group, a substituted or unsubstituted C 2 -C 60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

at least one substituent of the substituted C 3 -C 10 cycloalkylene group, the substituted C 3 -C 10 heterocycloalkylene group, the substituted C 3 -C 10 cycloalkenylene group, the substituted C 3 -C 10 heterocycloalkenylene group, the substituted C 6 -C 60 arylene group, the substituted C 2 -C 60 heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, and the substituted divalent non-aromatic condensed heteropolycyclic group is selected from

a deuterium, a halogen atom, a hydroxyl, a cyano, a nitro, an amino, an amidino, a hydrazine, a hydrazone, a carboxylic acid and a salt thereof, a sulfonic acid and a salt thereof, a phosphoric acid and a salt thereof, a C 1 -C 60 alkyl, a C 2 -C 60 alkenyl, a C 2 -C 60 alkynyl, and a C 1 -C 60 alkoxy;

a C 3 -C 60 alkyl group, a C 3 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 2 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 201 )(Q 202 ), —Si(Q 203 )(Q 204 )(Q 205 ), and —B(Q 206 )(Q 207 );

a C 3 -C 10 cycloalkyl group, a C 3 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 3 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a moonovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a moonovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 3 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 3 -C 60 alkynyl group, a C 2 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 3 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 3 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a moonovalent non-aromatic condensed heteropolycyclic group, —N(Q 211 )(Q 212 ), —Si(Q 213 )(Q 214 )(Q 215 ), and —B(Q 216 )(Q 217 ); and

—N(Q 221 )(Q 222 ), —Si(Q 223 )(Q 224 )(Q 225 ), and —B(Q 226 )(Q 227 ); and

xa1 to xa4 may be each independently selected from 0, 1, 2, and 3;

xa5 may be selected from 1, 2, 3, 4, and 5; and

R 201 to R 205 are each independently selected from

a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group;

a C 3 -C 60 alkyl group, a C 3 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 2 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, —N(Q 231 )(Q 232 ), —Si(Q 233 )(Q 234 )(Q 235 ), and —B(Q 236 )(Q 237 );

a C 3 -C 10 cycloalkyl group, a C 3 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 3 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group; and

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 3 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 3 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, a C 3 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 3 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 241 )(Q 242 ), —Si(Q 243 )(Q 244 )(Q 245 ), and —B(Q 246 )(Q 247 ); and

Q 201 to Q 207 , Q 211 to Q 217 , Q 221 to Q 227 , Q 231 to Q 237 , and Q 241 to Q 247 are each independently selected from

a hydrogen, a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid and a salt thereof, a sulfonic acid and a salt thereof, a phosphoric acid and a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 6 alkoxy group;

a C 3 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 3 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 2 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl group, a C 3 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 3 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group; and

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 3 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a moonovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 3 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, a C 3 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 3 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 2 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

wherein in Formulae 201 and 202,

L 201 to L 205 may be each independently selected from a phenylene, a naphthylenylene, a fluorenylene, a spiro-fluorenylene, a benzofluorenylene, a dibenzofluorenylene, a phenanthrenylene, an anthracenylene, a pyrenylene, a chrysenylene, a pyridinylene, a pyrazinylene, a pyrimidinylene, a pyridazinylene, a quinolinylene, an isoquinolinylene, a quinoxalinylene, a quinazolinylene, a carbazolylene, and a triazinylene; and

a phenylene group, a naphthylenylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a pyrenylene group, a chrysenylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a quinolinylene group, an isoquinolinylene group, a quinoxalinylene group, a quinazolinylene group, a carbazolylene group, and a triazinylene group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxyl group, and a salt thereof, a sulfonic acid, and a salt thereof, a phosphoric acid and a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

xa1 to xa4 may be each independently 0, 1, or 2;

xa5 may be 1, 2, or 3;

R 201 to R 204 are each independently selected from

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a phenyl group, a naphthyl group, an azulenyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, but they are not limited thereto.

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

For example, the compound represented by Formula 201 may be represented by Formula 201A-1 below, but is not limited thereto:

For example, the compound represented by Formula 202 may be represented by Formula 202A below, but is not limited thereto:

L 201 to L 203 , xa1 to xa3, xa5, and R 202 to R 204 in Formulae 201A, 201A-1, and 202A are already described above, R 211 may be the same as defined in connection with connection with R 212 , and R 213 to R 216 may be each independently selected from hydrogen, deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 10 cycloalkyl group, a C 3 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 3 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, and a non-aromatic condensed polycyclic group.

For example, in Formulae 201A, 201A-1, and 202A,

L 201 to L 203 may be each independently selected from

a phenylene, a naphthylenylene, a fluorenylene, a spiro-fluorenylene, a benzofluorenylene, a dibenzofluorenylene, a phenanthrenylene, an anthracenylene, a pyrenylene, a chrysenylene, a pyridinylene, a pyrazinylene, a pyrimidinylene, a pyridazinylene, a quinolinylene, an isoquinolinylene, a quinoxalinylene, a quinazolinylene, a carbazolylene, and a triazinylene; and

a phenylene group, a naphthylenylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a pyrenylene group, a chrysenylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a quinolinylene group, an isoquinolinylene group, a quinoxalinylene group, a quinazolinylene group, a carbazolylene group, and a triazinylene group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxyl group, and a salt thereof, a sulfonic acid, and a salt thereof, a phosphoric acid and a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

xa1 to xa3 may be each independently 0 or 1;

R 203 , R 211 , and R 212 may be each independently selected from

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

R 213 and R 214 are each independently selected from

a C 1 -C 20 alkyl group and a C 1 -C 20 alkoxy group;

a C 1 -C 20 alkyl group and a C 1 -C 20 alkoxy group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

R 215 and R 216 may be each independently selected from

a hydrogen, a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,

a C 1 -C 20 alkyl group and a C 1 -C 20 alkoxy group;

a C 1 -C 20 alkyl group and a C 1 -C 20 alkoxy group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a Spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

xa5 is 1 or 2.

R 213 and R 214 in Formulae 201A, and 201A-1 may bind to each other to form a saturated or unsaturated ring.

The compound represented by Formula 201, and the compound represented by Formula 202 may each include compounds HT1 to HT20 illustrated below, but are not limited thereto.

A thickness of the hole transport region may be in a range of about 100 Å to about 10,000 Å, e.g., about 100 Å to about 1,000 Å. When the hole transport region includes both a hole injection layer and a hole transport layer, a thickness of the hole injection layer may be in a range of about 100 Å to about 10,000 Å, e.g., about 100 Å to about 1,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2000 Å, for example about 100 Å to about 1500 Å. When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within these ranges, satisfactory hole transporting characteristics may be obtained without a substantial increase in driving voltage.

The hole transport region may further include, in addition to these materials, a charge-generation material to help improve conductive properties. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole transport region.

The charge-generation material may be, e.g., a p-dopant. The p-dopant may be one of a quinone derivative, a metal oxide, and a cyano group-containing compound, but is not limited thereto. Non-limiting examples of the p-dopant may include a quinone derivative, such as tetracyanoquinonedimethane (TCNQ) or 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane (F4-TCNQ); a metal oxide, such as a tungsten oxide or a molybdenum oxide, and Compound HT-D1 illustrated below, but are not limited thereto.

The hole transport region may further include, in addition to the hole injection layer and the hole transport layer, at least one of a buffer layer and an electron blocking layer. The buffer layer may help compensate for an optical resonance distance according to a wavelength of light emitted from the emission layer, and light-emission efficiency of a formed organic light-emitting device may be improved. For use as a material included in the buffer layer, materials that are included in the hole transport region may be used. The electron blocking layer prevents injection of electrons from the electron transport region.

An emission layer may be formed on the first electrode 110 or the hole transport region by using various methods, such as vacuum deposition, spin coating, casting, a LB method, ink-jet printing, laser-printing, or laser-induced thermal imaging. When the emission layer is formed by vacuum deposition or spin coating, deposition and coating conditions for the emission layer may be determined by referring to the deposition and coating conditions for the hole injection layer.

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. In some embodiments, the emission layer may have a stacked structure of a red emission layer, a green emission layer, and a blue emission layer, or may include a red-light emission material, a green-light emission material, and a blue-light emission material, which are mixed with each other in a single layer, to emit white light. According to another embodiment, the emission layer may be a white emission layer, and may further include a color converting layer or a color filter to turn white light into light of a desired color.

The emission layer may include a host and a dopant.

The emission layer may include at least one first material represented by Formula 1. For example, the host may include at least one first material represented by Formula 1.

When the emission layer includes the first material, the electron transport layer may include at least one second material. In an implementation, the electron transport layer may instead include other materials. When the emission layer includes the first material, and the electron transport layer includes the second material, the emission layer and the electron transport layer may be disposed adjacent to each other. For example, the emission layer may be directly adjacent to or may directly contact the electron transport layer.

The emission layer may include, in addition to the first material, at least one selected from TPBi, TBADN, ADN (also referred to as “DNA”), CBP, CDBP, TCP, SPPO, and MADN:

The dopant may be at least one selected from a fluorescent dopant and a phosphorescent dopant.

The phosphorescent dopant may include an organometallic complex represented by Formula 401 below:

wherein in Formula 401,

M may be selected from iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), euroform (Eu), terbium (Tb), and tolium (TM);

X 401 to X 404 may be each independently nitrogen or carbon;

rings A 401 and A 402 may be each independently selected from a substituted or unsubstituted benzene group, a substituted or unsubstituted naphthalene group, a substituted or unsubstituted fluorenene group, a substituted or unsubstituted spiro-fluorenene group, a substituted or unsubstituted indene group, a substituted or unsubstituted pyrrol group, a substituted or unsubstituted thiophene group, a substituted or unsubstituted furan group, a substituted or unsubstituted imidazole group, a substituted or unsubstituted pyrazole group, a substituted or unsubstituted thiazole group, a substituted or unsubstituted isothiazole group, a substituted or unsubstituted oxazole group, a substituted or unsubstituted isoxazole group, a substituted or unsubstituted pyridine group, a substituted or unsubstituted pyrazine group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted pyridazine group, a substituted or unsubstituted quinoline group, a substituted or unsubstituted isoquinoline group, a substituted or unsubstituted benzoquinoline group, a substituted or unsubstituted quinoxaline group, a substituted or unsubstituted quinazoline group, a substituted or unsubstituted carbazol group, a substituted or unsubstituted benzoimidazole group, a substituted or unsubstituted benzofuran group, a substituted or unsubstituted benzothiophene group, a substituted or unsubstituted isobenzothiophene group, a substituted or unsubstituted benzooxazole group, a substituted or unsubstituted isobenzooxazole group, a substituted or unsubstituted triazole group, a substituted or unsubstituted oxadiazole group, a substituted or unsubstituted triazine group, a substituted or unsubstituted dibenzofuran group, and a substituted or unsubstituted dibenzothiophene group;

at least one substituent of the substituted benzene group, substituted naphthalene group, substituted fluorenene group, substituted spiro-fluorenene group, substituted indene group, substituted pyrrol group, substituted thiophene group, substituted furan group, substituted imidazole group, substituted pyrazole group, substituted thiazole group, substituted isothiazole group, substituted oxazole group, substituted isoxazole group, substituted pyridine group, substituted pyrazine group, substituted pyrimidine group, substituted pyridazine group, substituted quinoline group, substituted isoquinoline group, substituted benzoquinoline group, substituted quinoxaline group, substituted quinazoline group, substituted carbazol group, substituted benzoimidazole group, substituted benzofuran group, substituted benzothiophene group, substituted isobenzothiophene group, substituted benzooxazole group, substituted isobenzooxazole group, substituted triazole group, substituted oxadiazole group, substituted triazine group, substituted dibenzofuran group, and substituted dibenzothiophene group may be selected from

a deuterium, a halogen atom, a hydroxyl, a cyano, a nitro, an amino, an amidino, a hydrazine, a hydrazone, a carboxylic acid and a salt thereof, a sulfonic acid and a salt thereof, a phosphoric acid and a salt thereof, a C 1 -C 60 alkyl, a C 2 -C 60 alkenyl, a C 2 -C 60 alkynyl, and a C 1 -C 60 alkoxy;

a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, and a C 1 -C 60 alkoxy group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —B(Q 406 )(Q 407 );

a C 3 -C 10 cycloalkyl group, a C 1 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 1 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, a C 1 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a moonovalent non-aromatic condensed heteropolycyclic group;

a C 3 -C 10 cycloalkyl, a C 1 -C 10 heterocycloalkyl, a C 3 -C 10 cycloalkenyl, a C 1 -C 10 heterocycloalkenyl, a C 6 -C 60 aryl, a C 6 -C 60 aryloxy, a C 6 -C 60 arylthio, a C 1 -C 60 heteroaryl, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 60 alkyl, a C 2 -C 60 alkenyl, a C 1 -C 60 alkynyl, a C 1 -C 60 alkoxy, a C 3 -C 10 cycloalkyl, a C 1 -C 10 heterocycloalkyl, a C 3 -C 10 cycloalkenyl, a C 1 -C 10 heterocycloalkenyl, a C 6 -C 60 aryl, a C 6 -C 60 aryloxy, a C 6 -C 60 arylthio, a C 1 -C 60 heteroaryl, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q 411 )(Q 412 ), —Si(Q 413 )(Q 414 )(Q 415 ), and —B(Q 416 )(Q 417 ); and

—N(Q 421 )(Q 422 ), —Si(Q 423 )(Q 424 )(Q 425 ), and —B(Q 426 )(Q 427 ); and

L 401 is an organic ligand;

xc1 is 1, 2, or 3; and

xc2 is 0, 1, 2, or 3.

L 401 may be a monovalent, divalent, or trivalent organic ligand. For example, L 401 may be selected from a halogen ligand (for example, Cl or F), a diketone ligand (for example, acetylacetonate, 1,3-diphenyl-1,3-propandionate, 2,2,6,6-tetramethyl-3,5-heptandionate, or hexafluoroacetonate), a carboxylic acid ligand (for example, picolinate, dimethyl-3-pyrazolecarboxylate, or benzoate), a carbon monooxide ligand, an isonitrile ligand, a cyano ligand, and a phosphorous ligand (for example, phosphine, and phosphaite), but is not limited thereto.

When A 401 in Formula 401 has two or more substituents, the substituents of A 402 may bind to each other to form a saturated or unsaturated ring.

When A 402 in Formula 402 has two or more substituents, the substituents of A 402 may bind to each other to form a saturated or unsaturated ring.

When xc1 in Formula 401 is two or more, a plurality of ligands

in Formula 401 may be identical or different. When xc1 in Formula 401 is two or more, A 401 and A 402 may be respectively directly connected to A 401 and A 402 of other neighboring ligands with or without a linker (for example, a C 1 -C 5 alkylene, or —N(R′)— (wherein R′ may be a C 1 -C 10 alkyl group or a C 6 -C 20 aryl group) or —C(═O)—) therebetween.

The phosphorescent dopant may include at least one of Compounds PD1 to PD74 below, but is not limited thereto:

According to another embodiment, the phosphorescent dopant may include PtOEP:

The fluorescent dopant may include at least one selected from DPAVBi, BDAVBi, TBPe, DCM, DCJTB, Coumarin 6, and C545T.

The fluorescent dopant may include a compound represented by Formula 501 below.

wherein in Formula 501,

Ar 501 may be selected from a naphthalene, a heptalene, a fluorenene, a spiro-fluorene, a benzofluorene, a dibenzofluorene, a phenalene, a phenanthrene, an anthracene, a fluoranthene, a triphenylene, a pyrene, a chrysene, a naphthacene, a picene, a perylene, a pentaphene, and an indenoanthracene;

a naphthalene group, a heptalene group, a fluorenene group, a spiro-fluorenene group, a benzofluorenene group, a dibenzofluorenene group, a phenalene group, a phenanthrene group, a 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, and an indenoanthracene group, each substituted with at least one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, a C 1 -C 60 alkoxy, a C 3 -C 10 cycloalkyl group, a C 3 -C 10 heterocycloalkyl group, a C 3 -C 10 cycloalkenyl group, a C 3 -C 10 heterocycloalkenyl group, a C 6 -C 60 aryl group, a C 6 -C 60 aryloxy, a C 6 -C 60 arylthio group, a C 2 -C 60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, and —Si(Q 501 )(Q 502 )(Q 503 ) (wherein Q 501 to Q 503 are each independently selected from a hydrogen, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 aryl group, and a C 1 -C 60 heteroaryl group);

L 501 to L 503 may be the same as defined in connection with L 201 ;

R 501 and R 502 are each independently selected from

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a triazinyl group, a dibenzofuranyl group, and a dibenzothiophenyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one selected from a deuterium, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a triazinyl group, a dibenzofuranyl group, and a dibenzothiophenyl group; and

xd1 to xd3 may be each independently selected from 0, 1, 2, and 3; and

xd4 may be selected from 1, 2, 3, and 4.

The fluorescent dopant may include at least one of Compounds FD1 to FD8:

An amount of the dopant in the emission layer may be, e.g., about 0.01 to about 15 parts by weight based on 100 parts by weight of the host, but is not limited thereto.

A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, e.g., 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.

Then, the electron transport region 180 may be disposed on the emission layer.

The electron transport region 180 may include at least one selected from a buffer layer, an electron transport layer (ETL), and an electron injection layer, but is not limited thereto.

For example, the electron transport region 180 may have an electron transport layer alone, a structure of electron transport layer/electron injection layer, or a structure of buffer layer/electron transport layer/electron injection layer, wherein layers of each structure are sequentially stacked from the emission layer in this stated order, but is not limited thereto.

The electron transport region 180 may include a buffer layer. For example, the luminescent efficiency and lifespan of an organic light-emitting device may be improved by optimizing balance of holes and electrons in an emission layer. The buffer layer may help prevent electrons from being provided into an emission layer too fast, and may help control the moving speed of electrons, thereby improving efficiency and lifespan of the organic light-emitting device.

The buffer layer may include at least one first material. When the buffer layer includes the first material, the electron transport layer may include the second material. In an implementation, the electron transport layer may instead include other materials. When the buffer layer includes the first material, and the electron transport layer includes the second material, the buffer layer and the electron transport layer may be disposed adjacent to each other. For example, the buffer layer may be directly adjacent to or may directly contact the electron transport layer.

When the electron transport region 180 includes the buffer layer, the buffer layer may be formed on the emission layer by using various methods, such as vacuum deposition, spin coating casting, a Langmuir-Blodgett (LB) method, ink-jet printing, laser-printing, or laser-induced thermal imaging. When the buffer layer is formed by vacuum deposition or spin coating, deposition and coating conditions for the buffer layer may be determined by referring to the deposition and coating conditions for the hole injection layer.

The buffer layer may include, e.g., at least one second material represented by Formula 2. When the buffer layer includes the second material (and, e.g., the emission layer includes the first material), the buffer layer and the emission layer may be disposed adjacent to each other. For example, the buffer layer may be directly adjacent to or may directly contact the emission layer.

A thickness of the buffer layer may be in a range of about 20 Å to about 1,000 Å, e.g., about 30 Å to about 300 Å. When the thickness of the hole blocking layer is within these ranges, the hole blocking layer may have excellent electron buffer characteristics without a substantial increase in driving voltage.

The electron transport region may include the electron transport layer. The electron transport layer may be formed on the emission layer or the buffer layer by using various methods, e.g., vacuum deposition, spin coating casting, a LB method, ink-jet printing, laser-printing, or laser-induced thermal imaging. When the electron transport layer is formed by vacuum deposition or spin coating, deposition and coating conditions for the electron transport layer may be determined by referring to the deposition and coating conditions for the hole injection layer.

The electron transport layer may include, e.g., at least one second material represented by Formula 2. When the electron transport layer includes the second material, the electron transport layer and the emission layer may be disposed adjacent to each other. For example, the electron transport layer may be directly adjacent to or may directly contact the emission layer.

In some embodiments, the electron transport layer may include at least one selected from BCP, Bphen, Alq 3 , Balq, TAZ, NTAZ, and a compound represented by Formula 601 below.

A thickness of the electron transport layer may be in a range of 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 satisfactory electron transport characteristics without a substantial increase in driving voltage.

In an implementation, the electron transport layer may further include, in addition to the materials described above, a metal-containing material.

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

The electron transport region may include an electron injection layer that allows electrons to be easily provided from the second electrode 190 .

The electron injection layer may be formed on the electron transport layer by using various methods, such as vacuum deposition, spin coating casting, a LB method, ink-jet printing, laser-printing, or laser-induced thermal imaging. When an electron injection layer is formed by vacuum deposition or spin coating, deposition and coating conditions for the electron injection layer may be determined by referring to the deposition and coating conditions for the hole injection layer.

The electron injection layer may include at least one selected from, LiF, NaCl, CsF, Li 2 O, BaO, and LiQ.

A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, e.g., 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 satisfactory electron injection characteristics without a substantial increase in driving voltage.

The second electrode 190 may be disposed on the organic layer 150 having such a structure. The second electrode 190 may be a cathode which is an electron injection electrode, and in this regard, a material for the second electrode 190 may include a metal, an alloy, an electrically conductive compound, and a mixture thereof, which have a relatively low work function. Examples of the second electrode 190 may include lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag). According to another embodiment, the material for forming the second electrode 190 may include ITO or IZO. The second electrode 190 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode.

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

A C 1 -C 60 alkyl group used herein refers to a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and detailed examples thereof are a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, an iso-amyl group, and a hexyl group. A C 1 -C 60 alkylene group used herein refers to a divalent group having the same structure as the C 1 -C 60 alkyl group.

A C 1 -C 60 alkoxy group used herein refers to a monovalent group represented by —OA 101 (wherein A 101 is the C 1 -C 60 alkyl group), and detailed examples thereof are a methoxy group, an ethoxy group, and an isopropyloxy group.

A C 2 -C 60 alkenyl group used herein refers to a hydrocarbon group formed by substituting at least one carbon double bond in the middle or terminal of the C 2 -C 60 alkyl group, and detailed examples thereof are an ethenyl group, a prophenyl group, and a butenyl group. A C 2 -C 60 alkenylene group used herein refers to a divalent group having the same structure as the C 2 -C 60 alkenyl group.

A C 2 -C 60 alkynyl group used herein refers to a hydrocarbon group formed by substituting at least one carbon triple bond in the middle or terminal of the C 2 -C 60 alkyl group, and detailed examples thereof are an ethynyl group, and a propynyl group. A C 2 -C 60 alkynylene group used herein refers to a divalent group having the same structure as the C 2 -C 60 alkynyl group.

A C 3 -C 10 cycloalkyl group used herein refers to a monovalent hydrocarbon monocyclic group having 3 to 10 carbon atoms, and detailed examples thereof are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. A C 3 -C 10 cycloalkylene group used herein refers to a divalent group having the same structure as the C 3 -C 10 cycloalkyl group.

A C 2 -C 10 heterocycloalkyl group used herein refers to a monovalent monocyclic group having at least one hetero atom selected from N, O, P, and S as a ring-forming atom and 2 to 10 carbon atoms, and detailed examples thereof are a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. A C 2 -C 10 heterocycloalkylene group used herein refers to a divalent group having the same structure as the C 2 -C 10 heterocycloalkyl group.

A C 3 -C 10 cycloalkenyl group used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one double bond in the ring thereof and does not have aromacity, and detailed examples thereof are a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. A C 3 -C 10 cycloalkenylene group used herein refers to a divalent group having the same structure as the C 3 -C 10 cycloalkenyl group.

A C 2 -C 10 heterocycloalkenyl group used herein refers to a monovalent monocyclic group that has at least one hetero atom selected from N, O, P, and S as a ring-forming atom, 2 to 10 carbon atoms, and at least one double bond in its ring. Detailed examples of the C 2 -C 10 heterocycloalkenyl group are a 2,3-hydrofuranyl group and a 2,3-hydrothiophenyl group. A C 2 -C 10 heterocycloalkenylene group used herein refers to a divalent group having the same structure as the C 2 -C 10 heterocycloalkenyl group.

A C 6 -C 60 aryl group used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and a C 6 -C 60 arylene group used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Detailed examples of the C 6 -C 60 aryl group are a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. When the C 6 -C 60 aryl group and the C 6 -C 60 arylene group each include two or more rings, the rings may be fused to each other.

A C 2 -C 60 heteroaryl group used herein refers to a monovalent group having a carboncyclic aromatic system that has at least one hetero atom selected from N, O, P, and S as a ring-forming atom, and 2 to 60 carbon atoms. A C 2 -C 60 heteroarylene group used herein refers to a divalent group having a carbocyclic aromatic system that has at least one hetero atom selected from N, O, P, and S as a ring-forming atom, and 2 to 60 carbon atoms. Examples of the C 2 -C 60 heteroaryl group are a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C 2 -C 60 heteroaryl group and the C 2 -C 60 heteroarylene group each include two or more rings, the rings may be fused to each other.

A C 6 -C 60 aryloxy group used herein indicates —OA 102 (wherein A 102 is the C 6 -C 60 aryl group), and a C 6 -C 60 arylthio group used herein indicates —SA 103 (wherein A 103 is the C 6 -C 60 aryl group).

A monovalent non-aromatic condensed polycyclic group used herein refers to a monovalent group that has two or more rings condensed to each other, only carbon atoms (for example, the number of carbon atoms may be in a range of 8 to 60) as a ring forming atom, and non-aromacity in the entire molecular structure. An example of the monovalent non-aromatic condensed polycyclic group is a fluorenyl group. A divalent non-aromatic condensed polycyclic group used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.

A monovalent non-aromatic condensed heteropolycyclic group used herein refers to a monovalent group that has two or more rings condensed to each other, has a heteroatom selected from N, O P, and S, other than carbon atoms (for example, the number of carbon atoms may be in a range of 2 to 60), as a ring forming atom, and has non-aromacity in the entire molecular structure. An example of the monovalent non-aromatic condensed heteropolycyclic group is a carbazolyl group. A divalent non-aromatic condensed heteropolycyclic group used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

The term “Ph” used herein refers to phenyl group, the term “Me” used herein refers to methyl group, the term “Et” used herein refers to ethyl group, and the term “ter-Bu” or “But” used herein refers to tert-butyl.

Hereinafter, an organic light-emitting device according to an embodiment will be described in detail with reference to Synthesis Examples and Examples.

The following Examples and Comparative Examples are provided in order to highlight characteristics of one or more embodiments, but it will be understood that the Examples and Comparative Examples are not to be construed as limiting the scope of the embodiments, nor are the Comparative Examples to be construed as being outside the scope of the embodiments. Further, it will be understood that the embodiments are not limited to the particular details described in the Examples and Comparative Examples.