Mechanoluminescent devices and articles, such as wearable articles, that include mechanoluminescent devices. The mechanoluminescent devices may have a lateral type architecture or a vertical type architecture. The mechanoluminescent devices may be sensors, including pressure sensors.

A light-emitting element includes an anode electrode, a cathode electrode, and a QD layer provided between the anode electrode and the cathode electrode, the QD layer containing the QDs. The QDs are AgIn.sub.xGa.sub.1-xS.sub.ySe.sub.1-y-based or ZnAgIn.sub.xGa.sub.1-xS.sub.ySe.sub.1-y-based Cd-free QDs (0?x<1, 0?y?1) and exhibit fluorescence characteristics having a fluorescent half width of 45 nm or less and a fluorescence quantum yield of 35% or more in a green wavelength region to a red wavelength region.

Mechanoluminescent devices and articles, such as wearable articles, that include mechanoluminescent devices. The mechanoluminescent devices may have a lateral type architecture or a vertical type architecture. The mechanoluminescent devices may be sensors, including pressure sensors.

A semiconductor nanocrystal can have a photoluminescent quantum yield of at least 90%, at least 95%, or at least 98%. The nanocrystal can be made by sequentially contacting a nanocrystal core with an M-containing compound and an X donor, where at least one of the M-containing compound and the X donor is substoichiometric with respect to forming a monolayer on the nanocrystal core.

A method for preparing a quantum dot includes supplying a first mixture including a first precursor material including a silver precursor, an indium precursor, a first gallium precursor, and a first solvent including oleylamine, trioctylphosphine oxide, and trioctylamine, adding a first sulfur precursor to the first mixture to form cores including silver, indium, gallium, and sulfur, reacting the cores with a second precursor material including a second sulfur precursor and a second gallium precursor to form a first shell around each of the cores, wherein the cores including the first shells comprise first particles, and adding a first element precursor and a second element precursor to a second mixture, the second mixture including the first particles and a second solvent, to form a second shell around each of the first shells.

The present disclosure describes luminescent solar concentrators that include photoluminescent nanoparticles. The photoluminescent nanoparticles include a semiconductor nanocrystal that sensitizes the luminescence of a defect. The defect can include, for example, an atom, a cluster of atoms, or a lattice vacancy. The defect can be incorporated into the semiconductor nanocrystal, adsorbed onto, or otherwise associated with the surface of the semiconductor nanocrystal.

The present invention firstly relates to a security feature for a security or value document. The security feature comprises a zinc sulfide luminophore in the form of particles. The zinc sulfide luminophore has the general chemical formula ZnS: Cu.sub.x, M.sub.y, X.sub.z; here, M represents one or more elements from a group comprising the chemical elements Co, In and Ni; X represents one or more elements from a group comprising the halides F, Cl, Br and I; and the following applies: 0<x<0.002 and 0?y<0.00015 and 0?z<0.00050. The particles each have cubic phase portions and hexagonal phase portions. When excited by an electrical field, the zinc sulfide luminophore emits a first radiation in the range of the light spectrum between 580 nm and 780 nm. When excited by heating the luminophore to a temperature between 100? C. and 150? C., the zinc sulfide luminophore emits a second radiation in the light spectrum. Furthermore, the invention relates to a security and value document, which may for example be a bank note or a passport, an identity card, a driving license or a postage stamp. The invention also relates to a method for detecting and/or verifying the security feature according to the invention.

Provided are a quantum dot, a method of preparing the same, and an electronic apparatus including the same, the quantum dot including a core including copper (Cu), a Group III element, a Group VI element, and gallium (Ga), a first shell covering the core, and a second shell covering the first shell, wherein the first shell includes a Group III-VI compound.

A semiconductor nanocrystal include a first I-III-VI semiconductor material and have a luminescence quantum yield of at least 10%, at least 20%, or at least 30%. The nanocrystal can be substantially free of toxic elements. Populations of the nanocrystals can have an emission FWHM of no greater than 0.35 eV.

A luminescent glass-ceramic material, its manufacturing method, and a light emitting device including the luminescent glass-ceramic material are provided. The luminescent glass-ceramic material includes a glass material and phosphors, wherein the glass material includes SiO.sub.2, Al.sub.2O.sub.3, Na.sub.2O, K.sub.2O, CaO, and B.sub.2O.sub.3.