A method is disclosed for forming a blended phosphor composition. The method includes the steps of firing precursor compositions that include europium and nitrides of at least calcium, strontium and aluminum, in a refractory metal crucible and in the presence of a gas that precludes the formation of nitride compositions between the nitride starting materials and the refractory metal that forms the crucible. The resulting compositions can include phosphors that convert frequencies in the blue portion of the visible spectrum into frequencies in the red portion of the visible spectrum.

A light emitting device includes a light emitting element having a peak emission wavelength of 410 nm to 440nm and a phosphor member. The phosphor member includes a first phosphor having a peak emission wavelength of 430 nm to 500 nm and containing an alkaline-earth phosphate, a second phosphor having a peak emission wavelength of 440 nm to 550 nm and containing at least one of an alkaline-earth aluminate and a silicate containing Ca, Mg, and Cl, a third phosphor having a peak emission wavelength of 500 nm to 600 nm and containing a rare-earth aluminate, a fourth phosphor having a peak emission wavelength of 610 nm to 650 nm and containing a silicon nitride containing Al and at least one of Sr and Ca, and a fifth phosphor having a peak emission wavelength of 650 nm to 670 nm and containing a fluorogermanate.

Provided is a method of producing a β-sialon fluorescent material having a high light emission intensity and an excellent light emission luminance. The method includes preparing a calcined product having a composition of β-sialon containing an activating element; grinding the calcined product to obtain a ground product; and heat-treating the ground product to obtain a heat-treated product. A specific surface area of the ground product is 0.2 m.sup.2/g or more.

A cadmium free quantum dot not including cadmium and including: a semiconductor nanocrystal core comprising indium and phosphorous, a first semiconductor nanocrystal shell disposed on the semiconductor nanocrystal core and comprising zinc and selenium, and a second semiconductor nanocrystal shell disposed on the first semiconductor nanocrystal shell and comprising zinc and sulfur, a composition and composite including the same, and an electronic device.

A method can be used for producing a powdery precursor material for an optoelectronic component having a first phase of the following general composition (Ca.sub.1-a-b-c-d-eZn.sub.dMg.sub.eSr.sub.cBa.sub.bX.sub.a).sub.2Si.sub.5N.sub.8, wherein X is an activator that is selected from the group of the lanthanoids and wherein the following applies: 0<a<1 and 0≦b≦1 and 0≦c≦ and 0≦d≦1 and 0≦e≦1. The method includes producing a powdery mixture of starting materials. The starting materials comprise ions of the aforementioned composition. At least silicon nitride having a specific surface area greater than or equal to 9 m/g is selected as a starting material and wherein the silicon nitride comprises alpha silicon nitride or is amorphous. The method also includes heat-treating the mixture under a protective gas atmosphere.

A phosphor having different light emission characteristics from the conventional phosphor, having high emission intensity and chemical and thermal stability, combined with LED of less than 450 nm. This phosphor includes an inorganic compound comprising: a crystal represented by Ba.sub.1Si.sub.4Al.sub.3N.sub.9, an inorganic crystal having the same crystal structure as Ba.sub.1Si.sub.4Al.sub.3N.sub.9 crystal, or a solid solution crystal thereof, comprising A element, D element, E element, and X element (A is one or more elements selected from Li, Mg, Ca, Sr, Ba, and La; D is one or more elements selected from Si, Ge, Sn, Ti, Zr, and Hf; E is one or more elements selected from B, Al, Ga, In, Sc, and Y; X is one or more elements selected from O, N, and F), into which M element is solid-solved (M is one or more elements selected from Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, and Yb).

A method for producing a ceramic conversion element and a light-emitting device are disclosed. In an embodiment the method includes providing at least four functional layers, each being a green body or a ceramic, wherein first functional layer is formed as a first luminous layer comprising an oxide and configured to at least partially convert light of a first wavelength range into light of a second wavelength range, wherein a second functional layer is formed as a second luminous layer comprising a nitride and configured to at least partially convert light of the first wavelength range into light of a third wavelength range, wherein a third functional layer is formed as a first intermediate layer, wherein the first intermediate layer comprises an oxide, wherein a fourth functional layer is formed as a second intermediate layer, and wherein the second intermediate layer comprises a nitride or an oxynitride.

The disclosure provides a quantum dot structure, a manufacturing method thereof, and a quantum dot light-emitting device. The quantum dot structure includes a core structure and a shell layer. The core structure includes a first metal element, at least one second metal element, and a non-metal element that bind through a chemical bond. The first metal element is a group III element, the non-metal element is a group V element, and the second metal element is a metal element different from the first metal element. In an inside-to-outside direction of the core structure, the content of the first metal element is in a descending order, the sum of content of the second metal element is in an ascending order, and the size of an optical band gap of the core structure is in the ascending order.

A method of treating an aqueous solution containing quantum dots, the method includes: a dissolution liquid preparation step of dissolving a quaternary ammonium salt and a potassium salt in an aqueous solution containing quantum dots to prepare a dissolution liquid; a phase separation step of heating the dissolution liquid to separate the dissolution liquid into two phases, which are a quaternary ammonium salt phase containing a large amount of the quaternary ammonium salt and a potassium salt phase containing a large amount of the potassium salt, and also to cause the quantum dots to be included in either one of the quaternary ammonium salt phase and the potassium salt phase; and a fractionation step of separating the quaternary ammonium salt phase and the potassium salt phase by fractionation.

A method for producing coated semiconductor nanoparticles, comprising a step of coating the surface of semiconductor nanoparticles with a metal oxide, wherein the surface of the semiconductor nanoparticles is coated with the metal oxide by treating a metal oxide precursor with microwave irradiation treatment.