A nanocrystal with a large Stokes shift includes a matrix domain having a composition of M1.sub.xM2.sub.yA.sub.z, and a plurality of seed domains which are distributed in the matrix domain and each of which has a composition of M1.sub.xM2.sub.yA.sub.z, wherein M1, M2, A, x, y, z, x, y, and z are as defined herein.

In certain embodiments, a first semiconductor material is vaporized to generate a vapor phase condensate. The vapor phase condensate is allowed to form nanoparticles. The nanoparticles are annealed to yield nanoparticles or cores. The cores are overcoated by introducing a solution containing second semiconductor material precursors in a coordinating solvent into a suspension of cores at a desired elevated temperature and mixing for a period of time sufficient to cause diffusion of the shell into the core. The diffusion of the shell into the core causes the quantum dots to exhibit a broadened optical emission. The produced quantum dots may be incorporated into a quantum dot based radiation source.

The invention relates to a mineral wool product comprising mineral fibers that is marked with an UV or IR active substance and can therefore be identified under exposure to suitable radiation.

The present invention relates to a nanocrystal having a core-shell structure, wherein the core comprises a core perovskite structure, and the shell comprises a shell perovskite structure and a compound comprising silicon and oxygen, wherein the shell per-ovskite structure is different from the core perovskite structure and comprises a low-dimensional perovskite structure that is doped 5 with a metal halide comprising a monovalent, divalent or trivalent metal ion. The present invention also relates to a process for preparing the nanocrystal, a substrate comprising the nanocrystal and the use of the nanocrystal.

Ruggedized luminescent nanoparticle tracers have luminescent nanoparticle cores coupled to a luminescent substrate. The substrate is a large-particle size phosphor, while the nanoparticles are photoluminescent quantum dots (QDs) whose emission spectra can be tuned based on their chemical composition, size, and fabrication (e.g., dopants). The QDs are encapsulated by a protective layer to form a nanoparticle core. The protective layer can shield the QDs from external environments that would otherwise damage the delicate QDs. The substrate is also encapsulated by a protective layer, and the protective layer of the nanoparticle core is coupled to the protective layer of the substrate via a molecular linker to form a tracer particle complex. The tracer particle complexes can be disposed in a silicate suspension for subsequent use.

Semiconductor nanoparticles that include a compound semiconductor mainly containing a Ag component, a Ge component, and a S component, wherein a content ratio of the Ag component to the Ge component is 1.0 or more and less than 7.5, in terms of molar ratio, and an average particle size of the semiconductor nanoparticles is 9 nm or less

Present invention provides a process for the synthesis of size and composition tunable colloidal PbMgS core and PbMgS/MS core shell quantum dots emitting in the near infrared (NIR) region of the spectrum in a single operation in a continuous flow reactor. M includes at least one of Cd, Mg, Zn and Cu metals.

The present invention provides a germanate luminescent material, a general molecular formula thereof being Zn.sub.2-2xGeO.sub.4:Mn.sub.2x,M.sub.y, wherein M is selected from at least one of Ag, Au, Pt, Pd, and Cu metal nano particles; 0<x0.05; M is doped in Zn.sub.2-2xGeO.sub.4:Mn.sub.2x, and y is a molar ratio of M to Zn.sub.2-2xGeO.sub.4:Mn.sub.2x, 0<y110.sup.2. The metal nano particle M is doped in a germanate luminescent substrate of the germanate luminescent material, and the metal nano particle M improves internal quantum efficiency of the luminescent material so that the germanate luminescent material has a high luminescent intensity. Also provided is a preparation method for the germanate luminescent material.

A preparation method of core-shell quantum dots is provided. The method includes mixing lead source, cadmium source, oleic acid, oleylamine and organic solvent to dissolve the lead source and the cadmium source in the organic solvent and thereby obtain a first solution; adding cesium oleate solution into the first solution for a first reaction to thereby obtain a first reaction solution; and adding sulfur source into the first reaction solution for a second reaction to thereby obtain the core-shell quantum dots, wherein the core-shell quantum dots are perovskite core-shell quantum dots (Cd:CsPb(Br.sub.1-xCl.sub.x).sub.3/CdS). The method simplifies simplifies a synthesis process of the perovskite core-shell quantum dots (Cd:CsPb(Br.sub.1-xCl.sub.x).sub.3/CdS), and used raw materials are cheaper and easily available. The core-shell quantum dots prepared by the method have uniform size and excellent deep blue light emitting performance.