Organic light-emitting device

An organic light-emitting device comprising:

• a first electrode;
• a second electrode;
• and an organic layer between the first electrode and the second electrode,
• wherein the organic layer comprises an emission layer,
• the emission layer comprises a host, a dopant, and a sensitizer,
• the sensitizer comprises ruthenium (Ru), palladium (Pd), rhenium (Re), osmium (Os), platinum (Pt), or any combination thereof, and
• the dopant and the sensitizer satisfy Conditions 1 and 2 below:
• 0.2 eV≤ΔEST(S) <Condition 1>
• |HOMO(D)−HOMO(S)|<0.5 eV <Condition 2>
• wherein, in Conditions 1 and 2,
• ΔEST(S) is a difference between a lowest excitation singlet energy level and a lowest excitation triplet energy level of the sensitizer,
• HOMO(D) is a highest occupied molecular orbital (HOMO) energy level of the dopant, and
• HOMO(S) is a HOMO energy level of the sensitizer,
• wherein the sensitizer comprises an organometallic compound represented by Formula 101 below:
• M11(L11)n11(L12)n12 <Formula 101>
• wherein, in Formula 101,
• M11 is ruthenium (Ru), palladium (Pd), rhenium (Re), osmium (Os), or platinum (Pt),
• L11 is a ligand represented by one of Formulae 1-1 to 1-4,
• L12 may be a monodentate ligand or a bidentate ligand,
• n11 is 1, and
• n12 may be 0, 1, or 2,
• wherein, in Formulae 1-1 to 1-4,
• A1 to A4 may each independently be a substituted or unsubstituted C5-C30 carbocyclic group, a substituted or unsubstituted C1-C30 heterocyclic group, or a non-cyclic group,
• Y11 to Y14 may each independently be a chemical bond, O, S, N(R91), B(R91), P(R91), or C(R91)(R92),
• T1 to T4 may each independently be a single bond, a double bond, *—N(R93)—*′, *—B(R93)—*′, *—P(R93)—*′, *—C(R93)(R94)—*′, *—Si(R93)(R94)—*′, *—Ge(R93)(R94)—*′, *—S—*′, *—Se—*′, *—O—*′, *—C(═O)—*, *—S(═O)—*′, *—S(═O)2—*′, *—C(R93)═*′, *═C(R93)—*′, *—C(R93)═C(R94)—*′, *—C(═S)—*′, or *—C≡C—*′,
• a substituent of the substituted C5-C30 carbocyclic group, a substituent of the substituted C1-C30 heterocyclic group, and R91 to R94 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C1-C60 alkylthio group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C1-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q1)(Q2)(Q3), —B(Q1)(Q2), —N(Q1)(Q2), —P(Q1)(Q2), —C(═O)(Q1), —S(═O)(Q1), —S(═O)2(Q1), —P(═O)(Q1)(Q2), or —P(═S)(Q1)(Q2), wherein each of the substituent of the substituted C5-C30 carbocyclic group and the substituent of the substituted C1-C30 heterocyclic group is not hydrogen,
• *1, *2, *3, and *4 each indicate a binding site to M11, and
• Q1 to Q3 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a substituted or unsubstituted C1-C60 alkylthio group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 alkyl aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C2-C60 alkyl heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a C1-C60 alkyl group that is substituted with at least one deuterium, —F, a cyano group, a C1-C60 alkyl group, and a C6-C60 aryl group, or any combination thereof, or a C6-C60 aryl group that is substituted with deuterium, —F, a cyano group, a C1-C60 alkyl group, or a C6-C60 aryl group, or any combination thereof.