Phosphors include a CaAlSiN.sub.3 family crystal phase, wherein the CaAlSiN.sub.3 family crystal phase comprises at least one element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

A crystal of a group 13 nitride has an upper surface and lower surface and is composed of a crystal of a group 13 nitride selected from gallium nitride, aluminum nitride, indium nitride or the mixed crystals thereof. When the upper surface of the layer of the crystal of the group 13 nitride is observed by cathode luminescence, the upper surface includes a linear high-luminance light-emitting part and a low-luminance light-emitting region adjacent to the high-luminance light-emitting part. A half value width of reflection at the (0002) plane of a X-ray rocking curve on the upper surface is 3000 seconds or less and 20 seconds or more.

An apparatus for manufacturing a quantum dot is provided, the apparatus including a first supplying part that provides a cationic precursor, a second supplying part that provides an anionic precursor, a mixing part connected to the first supplying part and the second supplying part, and a reaction part including a reaction tube configured to receive a liquid mixture of the cationic precursor and the anionic precursor from the mixing part and a first microwave generator configured to provide a microwave that is transmitted through the reaction tube. Therefore, the apparatus may produce a quantum dot of multi-element compounds.

The invention relates to a method for producing a non-oxide ceramic powder comprising a nitride, a carbide, a boride or at least one MAX phase with the general composition Mn+1AXn, where M=at least one element from the group of transition elements (Sc, Ti, V, Cr, Zr, Nb, Mo, Hf and Ta), A=at least one A group element from the group (Si, Al, Ga, Ge, As, Cd, In, Sn, Tl and Pb), X=carbon (C) and/or nitrogen (N) and/or boron (B), and n=1, 2 or 3. According to the invention, corresponding quantities of elementary starting materials or other precursors are mixed with at least one metal halide salt (NZ), compressed (pellet), and heated for synthesis with a metal halide salt (NZ). The compressed pellet is first enveloped with another metal halide salt, compressed again, arranged in a salt bath and heated therewith until the melting temperature of the salt is exceeded. Optionally, melted silicate can be added, which prevents the salt from evaporating at high temperatures. Advantageously, the method can be carried out in the presence of air.

The present invention belongs to the technical field of inorganic luminescent materials, particularly relates to a nitride fluorescent material, and further discloses a light-emitting device containing such a fluorescent material. The nitride fluorescent material contains a compound with a structure like M.sub.mAl.sub.xSi.sub.yN.sub.3: aR, bEu, cCe. The fluorescent material has very high physical stability and chemical stability, and the fluorescent material is better in crystallization, and thus has relatively high external quantum efficiency. When being applied to a light-emitting device, the fluorescent material can fully exert the advantages of good stability and high external quantum efficiency, and the light-emitting efficiency and stability of the light-emitting device can be further improved.

A layer of a crystal of a group 13 nitride selected from gallium nitride, aluminum nitride, indium nitride and the mixed crystals thereof has an upper surface and a bottom surface. The upper surface of the crystal layer of the group 13 nitride includes a linear high-luminance light-emitting part and a low-luminance light-emitting region adjacent to the high-luminance light-emitting part, observed by cathode luminescence. The high-luminance light-emitting part includes a portion extending along an m-plane of the crystal of the group 13 nitride.

A method of making a layered MXene material comprises a) introducing dried MAX phase powder into a vessel under anhydrous, inert conditions, the MAX phase powder comprising a general formula of M.sub.n+1AX.sub.n (n=1, 2, 3, or 4), wherein M is a transition metal or p-block metalloid selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Re, Cu, Ni, Ag, Zn, Cd, In, Sn, and Pb; interlayer A is a Group III, IV, or V metalloid selected from the group consisting of Al, Si, Ga, Ge, In, Sn, Pb, As, Bi, Sb, and X is one of C (carbon) and N (nitrogen); b) introducing a halogen and solvent to the dried MAX phase to create a halogen solution having a predetermined concentration; c) allowing a reaction to proceed for about 24 hours between 30-90 C. to create a reaction slurry comprising a MXene material.

A phosphor having a main crystal phase having a crystal structure identical to that of CaAlSiN.sub.3, and including a Ca element partially replaced with an Eu element, wherein the phosphor has a median size d50 of 12.0 m or more and 22.0 m or less, as measured according to a laser diffraction scattering method, and has a specific surface area of 1.50 m.sup.2/g or more and 10.00 m.sup.2/g or less, as measured according to a BET method.

The present disclosure is directed to antennas for transmitting and/or receiving electrical signals comprising a MXene composition, devices comprising these antennas, and methods of transmitting and receiving signals using these antennas.

A red phosphor represented by general formula: MSiAlN.sub.3, wherein M is at least one or more elements selected from Mg, Ca, Sr and Ba, and is partially replaced with Eu and has, as a host crystal, a crystal structure identical to that of a CaAlSiN.sub.3 crystal phase, and the phosphor has a bulk density of 0.70 g/cm.sup.3 or more and 2.30 g/cm.sup.3 or less. There is also provided a light-emitting element including the red phosphor and a semiconductor light-emitting element capable of exciting the red phosphor.