National Institute of Advanced Industrial Science and Technology

Agency of Industrial Science and Technology

Norio Murase

Masanori Ando

Ping Yang

Chunliang Li

Tetsuo Yazawa

An object of the present invention is to prepare a fine particle with high durability and high brightness, in which semiconductor nanoparticles are assembled. The present invention provides fluorescent fine particles comprising Cd- and Se-containing semiconductor nanoparticles dispersed in silicon-containing fine particles, wherein the average particle size of the silicon-containing fine particles is 20 to 100 nm, and the number of semiconductor nanoparticles dispersed in the silicon-containing fine particles is 10 or more.

Fluorescent particle, with semiconductor nanoparticles dispersed therein, fabricated by the sol-gel process

The present invention provides semiconductor-nanoparticle-dispersed small silica glass particles that emit bright fluorescent light with high fluorescence quantum yield and high density, compared to the conventional semiconductor-nanoparticle-dispersed small glass particles, and that have excellent fluorescence intensity stability over time; and a process for preparing the same. The semiconductor-nanoparticle-dispersed silica glass particles have a mean particle size of not less than 10 nanometers and not more than 5 micrometers, and contain a hydrolyzed alkoxide and semiconductor nanoparticles at a concentration of not less than 2&#xd7;10mol/l and not more than 1&#xd7;10mol/l. The particles emit fluorescent light with a fluorescence quantum yield (quantum yield) of 25% or more (and 60% or more), when dispersed in a solution.

Semiconductor-nanoparticle-dispersed small glass particles and process for preparing the same

The present invention provides a novel fluorescent material which has a luminance higher than that of the conventional rare earth ion-dispersed fluorescent materials and is excellent in light resistance and long-term stability, and also an optical device, such as a high-luminance display panel or lighting equipment, which uses such a fluorescent material. Semiconductor ultrafine particles are characterized by maintaining 50% or more fluorescence quantum yield of photoluminescence when they are kept dispersed in water at 10&#xb0; C. to 20&#xb0; C. in air for 5 days. The fluorescent material is obtained by dispersing such semiconductor ultrafine particles in a glass matrix using a sol-gel process.

Semiconductor ultrafine particles, fluorescent material, and light-emitting device

Nanoparticles having a core/shell structure consisting of a core comprising a Group III element and a Group V element at a molar ratio of the Group III element to the Group V element in the range of 1.25 to 3.0, and a shell comprising a Group II element and a Group VI element and having a thickness of 0.2 nm to 4 nm, the nanoparticles having a photoluminescence efficiency of 10% or more and a diameter of 2.5 to 10 nm; a method of producing the water-dispersible nanoparticles and a method of producing a glass matrix having the nanoparticles dispersed therein.

Water-dispersible nanoparticles having high luminous efficiency and method of producing the same

This invention provides a novel phosphor material that has better brightness than conventional phosphors using dispersed rare earth ions, and that possesses excellent light resistance, temporal stability, and the like, and a light-emitting device with high brightness comprising such phosphor material and an excitation ultraviolet light source corresponding to the properties thereof. A phosphor comprising a silicon-containing solid matrix and semiconductor superfine particles dispersed therein at a concentration of 5&#xd7;10to 1&#xd7;10mol/L, said semiconductor superfine particles having a fluorescence quantum yield of 3% or greater and a diameter of 1.5 to 5 nm, and a light-emitting device including said phosphor and a light source for excitation light with an intensity of 3 to 800 W/cm.

Semiconductor superfine particle phosphor and light emitting device

The present invention provides a thin-film fluorescent material in which semiconductor nanoparticles in a stable condition maintain a high fluorescence quantum yield and can be held at a high concentration in a glass matrix. The present invention also provides optical devices using the thin-film fluorescent material, such as high-brightness displays and lighting systems. The present invention relates to a fluorescent material, in which semiconductor nanoparticles with a fluorescence quantum yield of 15% or more and a diameter of 2 to 5 nanometers are dispersed in a glass matrix at a concentration of 5&#xd7;10mol/l or more and a method for manufacturing the same.

Fluorescent material with semiconductor nanoparticles dispersed in glass matrix at high concentration and method for manufacturing such fluorescent material

In a system (apparatus and method) which employs a light absorbent material surrounded by an optically transparent matrix as a recording medium and in which the presence or absence of emission light of a specific wavelength from unity of the light absorbent material is used for optical writing and reading, the light emitted in response to reading light is condensed and spectrally diffracted and the light intensity is detected for each specific wavelength and related to recorded information.

Growing community of inventors

Ikeda, Japan

Norio Murase