Provided are a heterocyclic compound represented by Formula 1-1 or 1-2, an organic light-emitting device including the heterocyclic compound, and an electronic apparatus including the organic light-emitting device:

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Formulae 1-1 and 1-2 may each be understood by referring to the descriptions of Formulae 1-1 and 1-2 provided herein.

The present disclosure relates to an organic electroluminescent compound represented by formula 1 and an organic electroluminescent device comprising the same. By comprising the compounds according to the present disclosure, it is possible to provide an organic electroluminescent device having improved luminous efficiency and/or lifetime properties.

A light-emitting device includes a first emission layer and a second emission layer, wherein the first emission layer includes a first hole-transporting host (HTH1), a first electron-transporting host (ETH1), and a first phosphorescent dopant (G1), and the second emission layer includes a second hole-transporting host (HTH2), a second electron-transporting host (ETH2), and a second phosphorescent dopant (G2). The electron mobility of the ETH1 is faster than the electron mobility of the ETH2, the hole mobility of the HTH2 is faster than the hole mobility of the HTH1, and the HTH1 and/or HTH2 includes deuterium.

A light-emitting device with high resistance to heat in a fabrication process is provided. The light-emitting device includes an EL layer between an anode and a cathode, and the EL layer includes at least a light-emitting layer. The light-emitting device includes, between the light-emitting layer and the cathode, a first layer in contact with the light-emitting layer. The light-emitting layer includes a light-emitting substance, a first organic compound, and a second organic compound. The first layer includes a third organic compound different from the first organic compound and the second organic compound. The light-emitting substance emits green to yellow light. The third organic compound includes a bicarbazole skeleton and a heteroaromatic ring skeleton including one selected from a pyridine ring, a diazine ring, and a triazine ring.

An electroluminescent device including a first electrode, a second electrode, and a light emitting layer disposed between the first electrode and the second electrode, the light emitting layer including semiconductor nanoparticle(s), wherein the semiconductor nanoparticle(s) does not include cadmium, wherein the semiconductor nanoparticle(s) includes a polycyclic organic ligand including functional group linked to a C.sub.6-50 condensed aromatic group, the functional group configured to link to the semiconductor nanoparticle(s), and the C.sub.6-50 condensed aromatic group including at least three cyclic moieties that includes a first aromatic ring and a second aromatic ring, and the first aromatic ring shares two carbon atoms with a first adjacent cyclic moiety and the second aromatic ring shares two carbon atoms with the first adjacent cyclic moiety, or the second aromatic ring shares two carbon atoms with a second adjacent cyclic moiety condensed with the first adjacent cyclic moiety.

A composition comprising an electron-donating polymer and an electron acceptor wherein the electron-donating polymer comprises a benzo[1,2-b:4,5-b′]dithiophene repeat unit and wherein a film of the electron-accepting material has a peak absorption wavelength greater than 1000 nm. The composition may be used as a photosensitive layer of an organic photodetector.

An organic light-emitting device includes: a first electrode; a second electrode facing the first electrode; an emission layer between the first electrode and the second electrode; a hole transport region between the first electrode and the emission layer; and an electron transport region between the emission layer and the second electrode, wherein the electron transport region includes a first compound, at least one selected from the hole transport region and the electron transport region includes a second compound, the first compound is represented by one selected from Formulae 1A to 1D, and the second compound is represented by Formula 2A or Formula 2B: ##STR00001##

An electroluminescent device and a display device including the electroluminescent device. The electroluminescent device includes a first electrode and a second electrode each having a surface opposite the other; a light emitting layer disposed between the first electrode and the second electrode, the light emitting layer including quantum dots; and an electron transport layer disposed between the light emitting layer and the second electrode, the electron transport layer including inorganic material nanoparticles including an anion dopant including P, N, C, Cl, F, Br, S, or a combination thereof.

A quantum-dot (QD) film, which includes a first QD layer including a first QD; and a first protection layer on the first QD layer and including a first organic compound, wherein the first organic compound includes at least two thiol groups, and a first one of the at least two thiol groups is anchored to the first QD, and an LED package, a QD light emitting diode and a display device including the QD film are provided.

An electron transport composition includes a metal oxide and a photoacid generator, wherein the photoacid generator has at least one of a halogenated triazine-based compound or an oxime sulfonate-based compound. When the electron transport composition is applied to a light-emitting element, the light-emitting element may exhibit improved luminous efficiency characteristics and element lifespan characteristics.