Provided are perovskite nanocrystalline particle and an optoelectronic device using the same. The perovskite nanocrystalline particle may include a perovskite nanocrystalline structure while being dispersible in an organic solvent. Accordingly, the perovskite nanocrystalline particle in accordance with the present invention has therein a perovskite nanocrystal having a crystalline structure in which FCC and BCC are combined; forms a lamellar structure in which an organic plane and an inorganic plane are alternately stacked; and can show high color purity since excitons are confined to the inorganic plane. In addition, the perovskite nanocrystalline particle have a particle size greater than or equal to a Bohr diameter beyond a quantum confinement effect, and simultaneously can implement high emission efficiency and emission wavelength which is almost not dependent on particle size. Furthermore, the perovskite nanocrystalline particle in accordance with the present invention, as a nanoparticle which is dispersible in an organic solvent, is applicable in various electronic devices such as light emitting devices, lasers, solar cells, etc.

Provided are: a light-emitting layer for a perovskite light-emitting device; a method for manufacturing the same; and a perovskite light-emitting device using the same. The method of the present invention for manufacturing a light-emitting layer for an organic and inorganic hybrid perovskite light-emitting device comprises a step of forming a first nanoparticle thin film by coating, on a member for coating a light-emitting layer, a solution comprising organic and inorganic perovskite nanoparticles including an organic and inorganic perovskite nanocrystalline structure. Thereby, a nanoparticle light emitter has therein an organic and inorganic hybrid perovskite having a crystalline structure in which FCC and BCC are combined; forms a lamella structure in which an organic plane and an inorganic plane are alternatively stacked; and can show high color purity since excitons are confined to the inorganic plane. In addition, it is possible to improve the luminescence efficiency and luminance of a device by making perovskite as nanoparticles and then introducing the same into a light-emitting layer.

Provided are a core-shell structured perovskite nanocrystalline particle light-emitting body, a method of preparing the same, and a light emitting device using the same. The core-shell structured organic-inorganic hybrid perovskite nanocrystalline particle light-emitting body or metal halide perovskite nanocrystalline particle light-emitting body is able to be dispersed in an organic solvent, and has a perovskite nanocrystal structure and a core-shell structured nanocrystalline particle structure. Therefore, in the perovskite nanocrystalline particle light-emitting body of the present invention, as a shell is formed of a substance having a wider band gap than that of a core, excitons may be more dominantly confined in the core, and durability of the nanocrystal may be improved to prevent exposure of the core perovskite to the air using a perovskite or inorganic semiconductor, which is stable in the air, or an organic polymer.

A quantum dot having a perovskite crystal structure and including a compound represented by Chemical Formula 1:
ABX.sub.3+α  Chemical Formula 1
wherein, A is a Group IA metal selected from Rb, Cs, Fr, and a combination thereof, B is a Group IVA metal selected from Si, Ge, Sn, Pb, and a combination thereof, X is a halogen selected from F, Cl, Br, and I, BF.sub.4, or a combination thereof, and α is greater than 0 and less than or equal to about 3; and wherein the quantum dot has a size of about 1 nanometer to about 50 nanometers.

The present disclosure relates to a composition that includes a particle and a surface species, where the particle has a characteristic length between greater than zero nm and 100 nm inclusively, and the surface species is associated with a surface of the particle such that the particle maintains a crystalline form when the composition is at a temperature between −180° C. and 150° C.

The embodiments of the present disclosure provides a quantum dot light emitting device, a light emitting layer and a manufacturing method thereof, and a display device. The device includes a perovskite quantum dot layer containing a second halogen element; a siloxane polymer film layer which is provided on a side of the perovskite quantum dot layer containing the second halogen element. The perovskite quantum dot layer containing the second halogen element and the siloxane polymer film layer are connected by a chemical bond.

A phosphor composition of an embodiment and a light emitting device package including the same includes: a green phosphor excited by blue light to emit green light; a first red phosphor of a nitride series which is excited by the blue light and emits first red light; and a second red phosphor of a fluorine series which is excited by the blue light and emits second red light, and is capable of emitting white light without deterioration of optical characteristics at a high temperature while improving luminous flux and color reproduction rate as compared with a light emitting device package including a conventional phosphor composition.

Photovoltaic cells incorporating the compounds A/M/X compounds as hole transport materials are provide. The A/M/X compounds comprise one or more A moieties, one or more M atoms and one or more X atoms. The A moieties are selected from organic cations and elements from Group 1 of the periodic table, the M atoms are selected from elements from at least one of Groups 3, 4, 5, 13, 14 or 15 of the periodic table, and the X atoms are selected from elements from Group 17 of the periodic table.

The present disclosure relates to a perovskite sheet that includes two outer layers, each including A′X′; and a first layer that includes BX.sub.2, where B is a first cation, A′ is a second cation, X is a first anion, X′ is a second anion, and the first BX.sub.2 layer is positioned between the two outer layers.

Embodiments of the present disclosure provide devices and systems including a halide perovskite and/or phosphor to produce and/or communicate using visible light, and the like.