The present invention relates to an orthogonal-phase compound and its nonlinear optical (NLO) crystal of BaGa.sub.7Se.sub.7, its producing method and uses thereof. Polycrystalline orthogonal-phase BaGa.sub.4Se.sub.7 was prepared by a high-temperature solid-phase reaction in a sealed silica tube. Large size single crystals of orthogonal-phase BaGa.sub.4Se.sub.7 could be prepared by the flux method or Bridgman method. BaGa.sub.4Se.sub.7 crystallizes in the point group mm2. Orthogonal-phase BaGa.sub.4Se.sub.7 has a powder second harmonic generation (SHG) efficiency of about 5 times that of AgGaS.sub.2 and is phase-matchable. The orthogonal-phase BaGa.sub.4Se.sub.7 is non-hygroscopic and has good mechanical properties, which makes it easy to cut, polish, and coat by normal processing. The orthogonal-phase BaGa.sub.4Se.sub.7 crystal has never been cracked during cutting and polishing. The orthogonal-phase compound and NLO crystal of BaGa.sub.4Se.sub.7 can be used as NLO devices.

Disclosed are stable films comprising Ag, In, Ga, and S (AIGS) nanostructures, or more one metal alkoxides, one or more metal alkoxide hydrolysis products, one or more metal halides, one or more metal halide hydrolysis products, one or more organometallic compounds, or one or more organometallic hydrolysis products, or combinations thereof, and at least one ligand bound to the nanostructures. In some embodiments, the AIGS nanostructures have a photon conversion efficiency of greater than 32% and a peak wavelength emission of 480-545 nm. In some embodiments, the nanostructures have an emission spectrum with a FWHM of 24-38 nm. In some embodiments, the nanostructures have a photon conversion efficiency (PCE) of at least 30% after being stored for 24 hours under yellow light and air storage conditions.

A color filter including a first pixel (or color conversion region) that is configured to emit a first light and a display device including the color filter. The first pixel includes a (first) quantum dot composite (or a color conversion layer including the quantum dot composite), wherein the quantum dot composite may include a matrix and a plurality of quantum dots dispersed (e.g., randomly) in the matrix, wherein the plurality of the quantum dots exhibit a multi-modal distribution (e.g., a bimodal distribution) including a first peak particle size and a second peak particle size in a size analysis, wherein the second peak particle size is greater than the first peak particle size, and a difference between the first peak particle size and the second peak particle size is less than or equal to about 5 nanometers (nm) (e.g., less than or equal to about 4.5 nm).

A color filter including a first layer including first quantum dots and a second layer including second quantum dots that are different from the first quantum dots, and disposed on the first layer, wherein a quantum yield of the first quantum dots is greater than a quantum yield of the second quantum dots, and wherein an absorption of blue light of the second quantum dots is greater than an absorption of the blue light of the first quantum dots.

A solid electrolyte including a compound represented by Formula 1 or 3, the compound having a glass transition temperature of -30° C. or less, and a glass or glass-ceramic structure,

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wherein, in Formula 1, Q is Li or a combination of Li and Na, K, or a combination thereof, M is a trivalent cation, or a combination thereof, X is a halogen other than F, pseudohalogen, OH, or a combination thereof, Z is a monovalent anion, or a combination thereof, 1<A<5, 0≤z<1, 0≤z1≤1, and 0≤k<1, wherein, in Formula 3, Q is Li or a combination of Li and Na, K, or a combination thereof; M is a trivalent cation, or a combination thereof, X is a halogen other than F, pseudohalogen, OH, or a combination thereof, Z is a monovalent anion, or a combination thereof, 0<a≤1, 0<b≤1, 0<a+b, a+b=4-A, 1<A<5, 0≤z<1, 0≤z1≤1, and 0≤k<1.

Proposed are a layered Group III-V compound having ferroelectric properties, a Group III-V compound nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by [Formula 1] M.sub.x−mA.sub.yB.sub.z (M is at least one of Group I or Group II elements, A is at least one of Group III elements, B is at least one of Group V elements, x, y, and z are positive numbers which are determined according to stoichiometric ratios to ensure charge balance when m is 0, and 0<m<x), and having ferroelectric-like properties.

A method for manufacturing a sputtering target with which an oxide semiconductor film with a small amount of defects can be formed is provided. Alternatively, an oxide semiconductor film with a small amount of defects is formed. A method for manufacturing a sputtering target is provided, which includes the steps of: forming a polycrystalline In-M-Zn oxide (M represents a metal chosen among aluminum, titanium, gallium, yttrium, zirconium, lanthanum, cesium, neodymium, and hafnium) powder by mixing, sintering, and grinding indium oxide, an oxide of the metal, and zinc oxide; forming a mixture by mixing the polycrystalline In-M-Zn oxide powder and a zinc oxide powder; forming a compact by compacting the mixture; and sintering the compact.

Semiconductor nanoparticles including Ag, In, Ga, and S are provided. In the semiconductor nanoparticles, a ratio of a number of Ga atoms to a total number of In and Ga atoms is 0.95 or less. The semiconductor nanoparticles emit light having an emission peak with a wavelength in a range of from 500 nm to less than 590 nm, and a half bandwidth of 70 nm or less, and have an average particle diameter of 10 nm or less.

An inorganic metal halide compound for one of a light emitting device and an optical member, the compound being represented by Formula 1 and having a double perovskite structure of Formula 1 as defined herein.

The present invention provides a two-dimensional double perovskite nanomaterial represented by the formula Cs.sub.2ABX.sub.6 or L.sub.4[Cs.sub.2ABX.sub.6].sub.n-1ABX.sub.8, wherein A is a metal ion selected from Ag(I), Au(I), and Cu(I); B is a metal ion selected from In(III), Bi(III), Sb(III), Fe(III), and Tl(III); X is a halogen; L is a ligand; and n represents the number of metal-halide octahedral layers present in said nanomaterial. The invention further provides a light emitting material and electronic-, optic-, or optoelectronic device comprising said nanomaterial; as well as methods for the preparation of said nanomaterial.