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

A ceramic lithium indium diselenide or like radiation detector device formed as a pressed material that exhibits scintillation properties substantially identical to a corresponding single crystal growth radiation detector device, exhibiting the intrinsic property of the chemical compound, with an acceptable decrease in light output, but at a markedly lower cost due to the time savings associated with pressing versus single crystal growth.

The present disclosure relates generally to nanoparticle formulations, and more specifically to nanoparticle and ligands used for imparting low-pH solubility in a range of solvents, including photoluminescent materials such as quantum dots.

The present invention provides the use of a lead (IV) containing compound to prepare a lead chalcogenide nanocrystal and a method for producing broadband lead chalcogenide nanocrystals in a low cost, size-controllable and scalable method, the method comprising contacting a lead (IV) containing compound with an organic acid and a chalcogen-containing reagent.

A method of producing nanoparticles comprises effecting conversion of a molecular cluster compound to the material of the nanoparticles. The molecular cluster compound comprises a first ion and a second ion to be incorporated into the growing nanoparticles. The conversion can be effected in the presence of a second molecular cluster compound comprising a third ion and a fourth ion to be incorporated into the growing nanoparticles, under conditions permitting seeding and growth of the nanoparticles via consumption of a first molecular cluster compound.

The preparation method for fluorescent quantum dots includes: carrying out solvothermal reaction on a first evenly mixed reaction system containing a silver source, a negative ion source and a weakly polar solvent to prepare a silver-based quantum dots precursor; and carrying out ion exchange reaction on a second evenly mixed reaction system containing the silver-based quantum dots precursor, a negative ion source and/or a metal positive ion source to obtain alloyed fluorescent quantum dots with a fluorescence emission peak wavelength of 500-1700 nm and an absolute quantum efficiency of more than 85%. The silver-based quantum dots are prepared through a simple high-temperature solvothermal method and then the alloyed quantum dots are obtained by the ion exchange method, and therefore the synthesis process is simple and controllable. The obtained fluorescent quantum dots can be prepared on large scale, and have adjustable fluorescence emission from visible to near-infrared region and excellent photostability.

To provide Cd-free chalcopyrite-based quantum dots with a narrow fluorescence FWHM and a high fluorescence quantum yield. The quantum dots of the present invention contain AgIn.sub.xGa.sub.1-xS.sub.ySe.sub.1-y or ZnAgIn.sub.xGa.sub.1-xS.sub.ySe.sub.1-y (where 0≤x<1 and 0≤y≤1) and exhibit fluorescence properties including a fluorescence FWHM of less than or equal to 45 nm and a fluorescence quantum yield of greater than or equal to 35% in the green wavelength range to the red wavelength range.

Disclosed herein are embodiments of a composition comprising a polymer or sol-gel and one or more nanocrystals. The composition is useful as a luminescent solar concentrator. The nanocrystals are dispersed in the polymer or sol-gel matrix so as to reduce or substantially prevent nanocrystal-to-nanocrystal energy transfer and a subsequent reduction in the emission efficiency of the composition. In some embodiments, the polymer matrix comprises an acrylate polymer. Also disclosed herein is a method for making the composition. Devices comprising the composition are disclosed. In some cases the polymer is the waveguide, in others the polymer is applied as a coating on a waveguide. In some examples, the device is a window.

A method for synthesizing two-dimensional (2D) nanosheets comprises heating a bulk material in a solvent. The process is scalable and can be used to produce solution-processable 2D nanosheets with uniform properties in large volumes.

Light emitting devices and LED-filaments comprise an excitation source (e.g. LED) and a photoluminescence material comprising a combination of a first narrow-band red photoluminescence material which generates light with a peak emission wavelength in a range 580 nm to 628 nm and a full width at half maximum emission intensity in a range 45 nm to 60 nm and a second narrow-band red photoluminescence material generates light with a peak emission wavelength in a range 628 nm to 640 nm and a full width at half maximum emission intensity in a range 5 nm to 20 nm. At least one of the first and second narrow-band red photoluminescence materials can comprise a narrow-band red phosphor or a quantum dot (QD) material.