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.

A device including an LED light source optically coupled to a phosphor selected from [Y,Gd,Tb,La,Sm,Pr,Lu].sub.3[Al,Ga].sub.5−aO.sub.12−3/2a:Ce.sup.3+ (wherein 0<a<0.5), beta-SiAlON:Eu.sup.2+, [Sr,Ca,Ba][Al,Ga,In].sub.2S.sub.4:Eu.sup.2+, alpha-SiAlON doped with Eu.sup.2+ and/or Ce.sup.3+, Ca.sub.1−h−rCe.sub.hEu.sub.rAl.sub.1−h[Mg,Zn].sub.hSiN.sub.3, (where 0<h<0.2, 0<r<0.2), Sr(LiAl.sub.3N.sub.4):Eu.sup.2+, [Ca,Sr]S:Eu.sup.2+ or Ce.sup.3+, [Ba,Sr,Ca].sub.bSi.sub.gN.sub.m:Eu.sup.2+ (wherein 2b+4g=3m), quantum dot materials, and combinations thereof; and a green-emitting U.sup.6+-doped phosphor having a composition selected from the group consisting of U.sup.6+-doped phosphate-vanadate phosphors, U.sup.6+-doped halide phosphors, U.sup.6+-doped oxyhalide phosphors, U.sup.6+-doped silicate-germanate phosphors, U.sup.6+-doped alkali earth oxide phosphors, and combinations thereof, is presented.

Proposed are a layered GaN compound, a nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by M.sub.1-xGa.sub.yN.sub.z (M is at least one of Group II elements, and 0<x≤1.0, 0.6≤y≤1.25, 0.75≤z≤1.5).

Provided are a quantum dot, a method of preparing the quantum dot, an optical member including the quantum dot, and an electronic device including the quantum dot. The quantum dot includes a core including indium (In), A.sup.1, and A.sup.2; and a shell covering the core. A.sup.1 is a Group V element, A.sup.2 is a Group III element other than indium, and the core includes a first region, and a second region covering the first region. The first region does not include A.sup.2, and includes indium and A.sup.1, and the second region includes indium, A.sup.1, and A.sup.2, and indium and A.sup.2 are alloyed with each other in the second region.

A luminescent composite material and a preparation method therefor. The luminescent composite material is prepared by mixing a precursor of a quantum dot and an oxide or a precursor thereof followed by high-temperature calcination. Compared with traditional methods, the method provided herein is a simple and low-cost synthesis process without using solvents, and is suitable for large-scale production. The luminescent composite material has high quantum efficiency, luminous intensity and luminous color purity and good photothermal stability, which can provide basis for theoretical research and applications of the luminescent composite material in high-performance photoluminescence devices, lasers and nonlinear optical devices.

The present invention discloses a multi-element perovskite material, and a single crystal, powder and a film thereof, as well as the applications thereof in photoluminescence and electroluminescence, in which the multi-element perovskite material is a multi-element fully-inorganic salt of non-lead metal halide and has a perovskite structure; and the chemical formula of the multi-element perovskite material is Cs.sub.2Na.sub.xAg.sub.1-xIn.sub.yBi.sub.1-yCl.sub.6, wherein 0≤x≤1, 0≤y≤1. Meanwhile, based on the very strong self-trapped exciton states of the double perovskite, the present invention proposes a high-efficiency single-phase broadband phosphor and an electroluminescent device.

To provide an oxide semiconductor film having stable electric conductivity and a highly reliable semiconductor device having stable electric characteristics by using the oxide semiconductor film. The oxide semiconductor film contains indium (In), gallium (Ga), and zinc (Zn) and includes a c-axis-aligned crystalline region aligned in the direction parallel to a normal vector of a surface where the oxide semiconductor film is formed. Further, the composition of the c-axis-aligned crystalline region is represented by In.sub.1+δGa.sub.1-δO.sub.3(ZnO).sub.m (0<δ<1 and m=1 to 3 are satisfied), and the composition of the entire oxide semiconductor film including the c-axis-aligned crystalline region is represented by In.sub.xGa.sub.yO.sub.3(ZnO).sub.m (0<x<2, 0<y<2, and m=1 to 3 are satisfied).

An object is to provide a new type of near-infrared ray-emitting phosphor which exhibits excellent emission intensity. A near-infrared ray-emitting phosphor is represented by a general formula, (Y,Lu,Gd).sub.3-x-y (Ga,Al,Sc).sub.5O.sub.12:(Cr.sub.x,(Yb,Nd).sub.y) (0.05<x<0.3, 0≤y<0.3).

A wavelength converting structure is disclosed, the wavelength converting structure including a spinel type SWIR phosphor material having emission wavelengths in the range of 1000 to 1700 nm, the SWIR phosphor material including AE.sub.1-x-zA.sub.z+0.5(x-y)D.sub.2+0.5(x-y)-z-u E.sub.zO.sub.4:Ni.sub.y,Cr.sub.u where AE=Mg, Zn, Co, or Be, or mixtures thereof, A=Li, Na, Cu, or Ag, or mixtures thereof, D=Ga, Al, B, In, or Sc, or mixtures thereof, and E=Si, Ge, Sn, Ti, Zr, or Hf, or mixtures thereof; where 0≤x≤1, 0<y≤0.1, 0≤z≤1, 0≤u≤0.2.

A wavelength converting structure is disclosed, the wavelength converting structure including an SWIR phosphor material having emission wavelengths in the range of 1000 to 1700 nm, the SWIR phosphor material including at least one of a perovskite type phosphor doped with Ni.sup.2+, a perovskite type phosphor doped with Ni.sup.2+ and Cr.sup.3+, and a garnet type phosphor doped with Ni.sup.2+ and Cr.sup.3+.