A light-emitting device including an organometallic compound represented by Formula 1, an electronic apparatus including the light-emitting device, and the organometallic compound represented by Formula 1 are provided.

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A light emitting element includes a polycyclic compound having a B-N-B structure and including a specific substituent in an emission layer, thereby showing high efficiency and long-life characteristics.

Embodiments provide a polycyclic compound and a light emitting element that includes the polycyclic compound. The light emitting element includes a first electrode, a second electrode disposed on the first electrode, and at least one functional layer disposed between the first electrode and the second electrode, wherein the at least one functional layer includes the polycyclic compound, which is represented by Formula 1. Formula 1 is defined in the specification. The light emitting element exhibits a long service life.

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Provided are a light-emitting device and an electronic apparatus including the same. The light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode. The interlayer includes an emission layer, and a hole transport region between the first electrode and the emission layer. The emission layer includes a transition metal-containing organometallic compound. The hole transport region includes an electron-blocking layer. The electron-blocking layer includes a first electron-blocking material and a second electron-blocking material, and the first electron-blocking material and the second electron-blocking material have different hole mobilities.

A compound comprising a first ligand L.sub.A of Formula I,

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is provided. In Formula I, Ring A is a 5-membered or 6-membered ring, and moiety G has a structure of

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where
the dashed line marked with * is coordinated to Ir; the dashed line marked with # is bonded to Ring A; Y is selected from the group consisting of BR, BRR′, NR, PR, O, S, Se, C═O, C═S, C═Se, C═NR, C═CRR′, S═O, SO.sub.2, CR, CRR′, SiRR′, and GeRR′. Formulations, OLEDs, and consumer products containing the compound are also provided.

A light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an interlayer between the first electrode and the second electrode and including an emission layer, wherein the emission layer includes at least one organometallic compound represented by Formula 1:

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wherein Formula 1 is the same as described herein.

An organometallic compound represented by Formula 1:

M.sub.1(Ln.sub.1).sub.n1(Ln.sub.2).sub.n2  Formula 1

wherein M.sub.1 is a transition metal, Ln.sub.1 is a ligand represented by Formula 1A, Ln.sub.2 is a ligand represented by Formula 1B, n1 is 1 or 2, and n2 is 1 or 2,

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wherein ring CY.sub.1 and ring CY.sub.2 are each independently a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group, ring CY.sub.41 is a phenyl group, ring CY.sub.42 is a 5-membered aromatic heterocyclic group, and the other substituents are as described herein.

A light-emitting device includes an organometallic compound represented by Formula 1, an electronic apparatus including the light-emitting device, and the organometallic compound represented by Formula 1 are provided:

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wherein substituents of Formula 1 are the same as described in the present specification.

A method for preparing three-dimensional perovskite nanopixels of a digital display is provided. The method includes steps of preparing precursor ink by mixing methylammonium halide and lead halide and adding them into another mixture, adding the precursor ink into a nanopipette, placing the nanopipette with the precursor ink above a silicon substrate and apart from the silicon substrate by a certain distance, configuring the nanopipette to come into contact with the Si substrate such that a portion of the precursor ink having an interface surface of a shape of a meniscus is formed between the nanopipette and the silicon substrate, performing rapid evaporation of the portion of the precursor ink to facilitate crystallization of perovskite, moving the nanopipette upwardly at a constant speed such that the crystallization of perovskite proceeds upwardly, and terminating the crystallization of perovskite to generate a freestanding nanopixel for emitting light.

A light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode. The interlayer includes an emission layer and a hole transport layer between the first electrode and the emission layer. The emission layer includes a first host, a second host, and a dopant, wherein the first host includes a hole-transporting host, and the second host includes an electron-transporting host or a bipolar host. The hole transport layer includes multiple hole transport layers, the hole transport layers each include a carbazole-based compound, and highest occupied molecular orbital (HOMO) energy levels of the carbazole-based compounds respectively included in neighboring ones of the hole transport layers are different from each other.