The present invention relates inter alia to a color display comprising nanoparticles and color filters.

Provided are: a light-emitting layer for a perovskite light-emitting device; a method for manufacturing the same; and a perovskite light-emitting device using the same. The method of the present invention for manufacturing a light-emitting layer for an organic and inorganic hybrid perovskite light-emitting device comprises a step of forming a first nanoparticle thin film by coating, on a member for coating a light-emitting layer, a solution comprising organic and inorganic perovskite nanoparticles including an organic and inorganic perovskite nanocrystalline structure. Thereby, a nanoparticle light emitter has therein an organic and inorganic hybrid perovskite having a crystalline structure in which FCC and BCC are combined; forms a lamella structure in which an organic plane and an inorganic plane are alternatively stacked; and can show high color purity since excitons are confined to the inorganic plane. In addition, it is possible to improve the luminescence efficiency and luminance of a device by making perovskite as nanoparticles and then introducing the same into a light-emitting layer.

A semiconductor light emitting element is provided. The semiconductor light emitting element has a semiconductor stack, an n-side conductor layer, a p-side conductor layer, a dielectric multilayered film, an n-side reflective layer and a p-side reflective layer, disposed in that order. The n-side and p-side reflective layers contain Ag as a major component and contain particles of at least one selected from an oxide, a nitride, and a carbide.

A nanocrystal capable of light emission includes a nanoparticle having photoluminescence having quantum yields of greater than 30%.

A semiconductor nanoparticle includes a core and a shell covering a surface of the core. The shell has a larger bandgap energy than the core and is in heterojunction with the core. The semiconductor nanoparticle emits light when irradiated with light. The core is made of a semiconductor that contains M.sup.1, M.sup.2, and Z. M.sup.1 is at least one element selected from the group consisting of Ag, Cu, and Au. M.sup.2 is at least one element selected from the group consisting of Al, Ga, In and Tl. Z is at least one element selected from the group consisting of S, Se, and Te. The shell is made of a semiconductor that consists essentially of a Group 13 element and a Group 16 element.

A semiconductor light emitting element is provided. The semiconductor light emitting element has a semiconductor stack, an n-side conductor layer, a p-side conductor layer, a dielectric multilayered film, an n-side reflective layer and a p-side reflective layer, disposed in that order. The n-side and p-side reflective layers contain Ag as a major component and contain particles of at least one selected from an oxide, a nitride, and a carbide.

Provided is a ternary or quaternary semiconductor nanoparticle that enables the band-edge emission and a less toxic composition. A semiconductor nanoparticle is provided that contains Ag, In, and S and has an average particle size of 50 nm or less, wherein the ratio of the number of atoms of Ag to the total number of atoms of Ag and In is 0.320 or more and 0.385 or less, the ratio of the number of atoms of S to the total number of atoms of Ag and In is 1.20 or more and 1.45 or less. The semiconductor nanoparticle is adapted to emit photoluminescence having a photoluminescence lifetime of 200 ns or less upon being irradiated with light having a wavelength in a range of 350 nm to 500 nm.

A semiconductor nanoparticle includes a core and a shell covering a surface of the core. The shell has a larger bandgap energy than the core and is in heterojunction with the core. The semiconductor nanoparticle emits light when irradiated with light. The core is made of a semiconductor that contains M.sup.1, M.sup.2, and Z. M.sup.1 is at least one element selected from the group consisting of Ag, Cu, and Au. M.sup.2 is at least one element selected from the group consisting of Al, Ga, In and Tl. Z is at least one element selected from the group consisting of S, Se, and Te. The shell is made of a semiconductor that consists essentially of a Group 13 element and a Group 16 element.

A method of producing semiconductor nanoparticles is provided. The method includes heating primary semiconductor nanoparticles and a salt of an element M.sup.1 in a solvent at a temperature set in a range of 100° C. to 300° C. The primary semiconductor nanoparticles contain the element M.sup.1, an element M.sup.2, optionally an element M.sup.3, and an element Z, and have an average particle size of 50 nm or less. The element M.sup.1 is at least one element selected from the group consisting of Ag, Cu, and Au. The element M.sup.2 is at least one element selected from the group consisting of Al, Ga, In, and Tl. The element M.sup.3 is at least one element selected from the group consisting of Zn and Cd. The element Z is at least one element selected from the group consisting of S, Se, and Te.

A semiconductor nanoparticle includes a core and a shell covering a surface of the core. The shell has a larger bandgap energy than the core and is in heterojunction with the core. The semiconductor nanoparticle emits light when irradiated with light. The core is made of a semiconductor that contains M.sup.1, M.sup.2, and Z. M.sup.1 is at least one element selected from the group consisting of Ag, Cu, and Au. M.sup.2 is at least one element selected from the group consisting of Al, Ga, In and Tl. Z is at least one element selected from the group consisting of S, Se, and Te. The shell is made of a semiconductor that consists essentially of a Group 13 element and a Group 16 element.