There is provided a protein-halide perovskite nanocrystal (p-HPNC) comprising: a crystalline core of halide perovskites and an outer layer made of protein surrounding the crystalline core. The protein has a net positive electric charge at a pH of 3 or less in its free state. The protein is linked to the surface of the crystalline core, and the halide perovskites have a formula ABX.sub.3, where A is a monovalent cation, B is a divalent cation, and X is a monovalent halide anion.

Provided are a backlight unit, a down-conversion medium including the same, and a display device including the down-conversion medium. The backlight unit includes a light source configured to generate blue light; and an optical film configured to absorb a portion of the blue light generated from the light source to generate red light and green light, wherein the optical film includes a quantum dot matrix in which semi-metal element oxide is embedded.

Bulk assemblies are provided, which may have desirable photoluminescence quantum efficiencies. The bulk assemblies may include two or more metal halides, and a wide band gap organic network. The wide band gap organic network may include organic cations. The metal halides may be disposed in the wide band gap organic network. Light emitting composite materials also are provided.

A luminophore may have the general formula A.sub.2EZ.sub.zX.sub.x:RE,

where: A is selected from the group of the monovalent elements; E is selected from the group of the tetravalent, pentavalent, or hexavalent elements; Z is selected from the group of the divalent elements; X is selected from the group of the monovalent elements; RE is selected from activator elements; 2+e=2z+x, with the charge number e of the element E; and x+z=5 and z>0.

A process is also disclosed that is directed to producing the luminophore and a corresponding radiation-emitting component.

A method of manufacturing of an ink (100) composition comprises a biphasic ligand exchange process. A first phase liquid (10) comprising a nonpolar solvent (11) with a colloidal suspension of nanoparticles (1) that are capped with a shell of non polar ligands (2) is contacted with a second phase liquid (20) comprising a polar solvent (21) with second ligand (3). The second ligand comprises at least one surface binding head group that has an affinity for binding to the nanoparticle; and an ionically charged tail group. The second ligands displace the first ligands to form a dispersion of the nanoparticles that are capped with a shell of the second ligands in the second phase liquid. The nanoparticles can be separated from the second phase liquid. The separated nanoparticles can be (re)dispersed in a printable liquid medium, e.g. used for printing a photoactive layer.

A luminescent component includes a first element comprising a first solid polymer composition, wherein the first solid polymer composition includes first luminescent crystals, wherein the first luminescent crystals are of the perovskite structure, and are selected from compounds of formula (I): M.sup.1.sub.aM.sup.2.sub.bX.sub.c, wherein M.sup.1 represents Cs, optionally doped with up to 30 mol % of one or more other metals having coordination number 12, M.sup.2 represents Pb, optionally doped with up to 30 mol % of one or more other metals having coordination number 6, X independently represents anions selected from the group consisting of Cl, Br, I, cyanide, and thiocyanate. The first luminescent crystals are of size between 3 nm and 3000 nm, and emit light of a first wavelength in response to excitation by light with a wavelength shorter than the first wavelength. An encapsulation including a polymer or an inorganic matrix encloses the first element.

The present invention is directed to methods of preparing metal sulfide, metal selenide, or metal sulfide/selenide nanoparticles and the products derived therefrom. In various embodiments, the nanoparticles are derived from the reaction between precursor metal salts and certain sulfur- and/or selenium-containing precursors each independently having a structure of Formula (I), (II), or (III), or an isomer, salt, or tautomer thereof, where Q.sup.1,Q.sup.2,Q.sup.3,R.sup.1,R.sup.2,R.sup.3,R.sup.5, and X are defined within the specification.

Inorganic perovskites doped with oxygen atoms or fluorine atoms, methods for making the doped perovskites, and hard radiation detectors incorporating the doped perovskites as photoactive layers are provided. The doped perovskites utilize lead oxide, lead fluoride, or compounds that thermally decompose into lead oxide or lead fluoride as dopant atom sources. During the crystallization of a perovskite in the presence of the dopant atom sources, oxygen or fluoride atoms from the dopant source are incorporated into the perovskite crystal lattice.

A device including a material including halide perovskite nanocrystals forming a film and configured to receive first electromagnetic radiation having a first wavelength emitted by an excitation source, the first electromagnetic radiation is modulated to include information prior to being received by the material, the material is configured to absorb the first electromagnetic radiation including the information and to emit second electromagnetic radiation having a second wavelength and also including the information, the second wavelength being in the visible range, and the first wavelength of the first electromagnetic radiation is shorter than the visible range; a detector configured to receive the second electromagnetic radiation and to extract the information; and a screen connected to the detector and configured to display the information.

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.