335 results about "Semiconductor Nanoparticles" patented technology

A method for creating an organically capped Group IV semiconductor nanoparticle is disclosed. The method includes flowing a Group IV semiconductor precursor gas into a chamber. The method also includes generating a set of Group IV semiconductor precursor radical species from the Group IV semiconductor precursor gas with a laser pyrolysis apparatus, wherein the set of the Group IV semiconductor precursor radical species nucleate to form the Group IV semiconductor nanoparticle; and flowing an organic capping agent precursor gas into the chamber. The method further includes generating a set of organic capping agent radical species from the organic capping agent precursor gas, wherein the set of organic capping agent radical species reacts with a surface of the Group IV semiconductor nanoparticle and forms the organically capped Group IV semiconductor nanoparticle.

The invention provides a water soluble complex comprising an inner core of a metal or semi-conductor nanoparticle. The nanoparticle is coated with a hydrophobic ligand, which is encapsulated in a micelle. In an aqueous medium, the micelle comprises a hydrophilic shell and a hydrophobic core, the hydrophilic shell comprising a plurality of hydrophilic moieties, the hydrophobic core comprising a plurality of hydrophobic moieties, each hydrophobic moiety comprising at least one chain, each chain comprising a minimum of 8 atoms; wherein the total number of atoms in all chains for each moiety comprises at least 24 atoms. The micelle has a minimum average diameter of approximately 5 nm and a maximum average diameter of approximately 45 nm.

A method is provided for preparing luminescent semiconductor nanoparticles composed of a first component X, a second component A, and a third component B, wherein X, A, and B are different, by combining B with X and A in an amount such that the molar ratio B:(A+B) is in the range of approximately 0.001 to 0.20 and the molar ratio X:(A+B) is in the range of approximately 0.5:1.0 to 2:1. The characteristics of the thus-prepared nanoparticles can be substantially similar to those of nanoparticles containing only X and B while maintaining many useful properties characteristic of nanoparticles containing only X and A. The nanoparticles so prepared can additionally exhibit emergent properties such as a peak emission energy less than that characteristic of a particle composed of XA or XB alone; this method is particularly applicable to the preparation of stable, bright nanoparticles that emit in the red to infrared regions of the electromagnetic spectrum. Luminescent semiconductor nanoparticles having exemplary properties are also provided.

A light emitting layer including a plurality of light emitting particles embedded within a host matrix material. Each of said light emitting particles includes a population of semiconductor nanoparticles embedded within a polymeric encapsulation medium. A method of fabricating a light emitting layer comprising a plurality of light emitting particles embedded within a host matrix material, each of said light emitting particles comprising a population of semiconductor nanoparticles embedded within a polymeric encapsulation medium. The method comprises providing a dispersion containing said light emitting particles, depositing said dispersion to form a film, and processing said film to produce said light emitting layer.

A field effect transistor (FET) with a source electrode and a drain electrode distanced apart from each other on a semi-conductor substrate, and a gate electrode consisting of a uniform layer of reduced graphene oxide encapsulated semiconductor nanoparticles (rGO-NPs), wherein the gate electrode is disposed between and contacts both the source and drain electrodes. Methods of making and assay methods using the FETs are also disclosed, including methods in which the rGO-NPs are functionalized with binding partners for biomarkers.

The invention provides a water soluble complex comprising an inner core of a metal or semi-conductor nanoparticle. The nanoparticle is coated with a hydrophobic ligand, which is encapsulated in a micelle. In an aqueous medium, the micelle comprises a hydrophilic shell and a hydrophobic core, the hydrophilic shell comprising a plurality of hydrophilic moieties, the hydrophobic core comprising a plurality of hydrophobic moieties, each hydrophobic moiety comprising at least one chain, each chain comprising a minimum of 8 atoms; wherein the total number of atoms in all chains for each moiety comprises at least 24 atoms. The micelle has a minimum average diameter of approximately 5 nm and a maximum average diameter of approximately 45 nm.

A semiconductor photocatalyst responsive to visual light is composed of the particles of metallic oxide chosen from iron oxide, nickel oxide, cabolt oide, copper oxide, etc, the non-metal element chosen from N, C, S, B and P and semiconductor nanoparticles chosen frmo TiO2, SnO2, ZnO, CdS and WO3.

The present invention provides seeded rod (SR) nanostructure systems including an elongated structure embedded with a seed structure being a core / shell structure or a single-material rod element. The SR systems disclosed herein are suitable for use in a variety of electronic and optical devices.

A method is described for the manufacture of semiconductor nanoparticles. Improved yields are obtained by use of a reducing agent or oxygen reaction promoter.

Semiconductor nanoparticles having high luminescence properties that are preferable for applications and uses of biotechnology are provided. With the use of electric charges on the surfaces of particles, the particles and selected polymers are allowed to electrostatically bind to each other, such that the surfaces of the particles are coated. The polymers are allowed to crosslink to each other, resulting in the improved durability of the particles. Further, functional groups contained in the polymers are exposed on the surfaces of the particles. Accordingly, semiconductor nanoparticles that are preferably utilized for applications such as staining and labeling of biopolymers have been synthesized.

This invention provides a phosphor material capable of absorbing primary light and converting that light into white light having a high color rendering index and illumination devices made from the phosphor material. The white light may have a color rendering index of 100 and may be produced with an efficiency of at least 30 lm / w. In one embodiment, the illumination device includes a secondary light source made from a plurality of Group IV semiconductor nanoparticles.

A method for synthesis of high quality colloidal nanoparticles using comprises a high heating rate process. Irradiation of single mode, high power, microwave is a particularly well suited technique to realize high quality semiconductor nanoparticles. The use of microwave radiation effectively automates the synthesis, and more importantly, permits the use of a continuous flow microwave reactor for commercial preparation of the high quality colloidal nanoparticles.

A plurality of semiconductor nanoparticles having an elementally passivated surface are provided. These nanoparticles are capable of being suspended in water without substantial agglomeration and substantial precipitation on container surfaces for at least 30 days. The method of making the semiconductor nanoparticles includes reacting at least a first reactant and a second reactant in a solution to form the semiconductor nanoparticles in the solution. A first reactant provides a passivating element which binds to dangling bonds on a surface of the nanoparticles to passivate the surface of the nanoparticles. The nanoparticle size can be tuned by etching the nanoparticles located in the solution to a desired size.

Disclosed herein are core-shell type nanoparticles comprising nanoparticle cores made of a metal or semiconductor, and shells made of crystalline metal oxide formed on the surfaces of the nanoparticle cores, as well as a preparation method thereof. According to the disclosed invention, the core-shell nanoparticles, consisting of metallic or semiconductor cores and crystalline metal oxide shells, can be prepared by epitaxially growing metal oxide on the surfaces of the metallic or semiconductor nanoparticle cores. By virtue of the crystalline metal oxide shells, the core nanoparticle made of metal or semiconductor can ensure excellent chemical and mechanical stability, and the core-shell nanoparticles can show new properties resulting from the interaction between the metal cores and the metal oxide crystal shells.

Semiconductor nanoparticles are doped with paramagnetic ions to serve as dual-mode optical and magnetic resonance imaging (MRI) contrast agents. These nanoparticles can be constructed in smaller diameters than typical MRI agents. The dual-modality nature allows the particles to be used for in vivo imaging by MRI, and then followed by histology with optical imaging techniques.

The present invention describes nanocomposite material structures including layers forming p-n and p-i-n homo- and heterojunctions for application in photovoltaics, solar cells, photodetectors, and light emitting devices, comprising semiconductor nanoparticles, such as colloidal semiconductor nanocrystals, nanorods, nanowires, nanotubes, etc., wherein at least one of the layers is made of hydrogenated amorphous or microcrystalline / nanocrystalline silicon or their alloys enabling low-temperature fabrication processes preventing any degradation of physical properties of the nanoparticles.

The invention relates to a preparation method of a solar light splitting water hydrogen production catalyst without noble metal as a cocatalyst. Specifically, graphene is used as a cocatalyst to prepare semiconductor nanoparticle-graphene composite photocatalysts, including CdS-graphene composites and TiO2-graphene composites. The hydrogen production efficiency of the photocatalyst with graphene as the cocatalyst is comparable to or even higher than that of the photocatalyst containing the same mass of noble metal Pt under the same hydrogen production conditions. Graphene materials have good electron aggregation and transport functions, which promote the effective separation of electrons and holes, reduce the probability of proton recombination, and increase the photocatalytic efficiency of photocatalysts and the efficiency of photo-splitting water to produce hydrogen; and the preparation method of graphene materials is simple , cheaper than precious metals, and has no pollution to the environment, which is conducive to large-scale preparation and production. The preparation of photocatalysts using graphene as a cocatalyst has opened up a new method for reducing the cost of hydrogen production from solar energy and improving the efficiency of hydrogen production by photolysis of water.

A semiconductor nanoparticle phosphor includes a nanoparticle core composed of a group-XIII and -XV semiconductor, a first shell for coating the nanoparticle core, and a second shell for coating the first shell, a difference in a lattice constant between the nanoparticle core and the second shell being smaller than a difference in the lattice constant between the nanoparticle core and the first shell, or the first shell being smaller in the lattice constant than the nanoparticle core and the second shell being greater in the lattice constant than the nanoparticle core, or the first shell being greater in the lattice constant than the nanoparticle core and the second shell being smaller in the lattice constant than the nanoparticle core.

Semiconductor nanoparticle complexes comprising semiconductor nanoparticles in association with cationic polymers are described. Also described are methods for enhancing the transport of semiconductor nanoparticles across biological membranes to provide encoded cells. The methods are particularly useful in multiplex settings where a plurality of encoded cells are to be assayed. Kits comprising reagents for performing such methods are also provided.

In a photoelectric transfer device having a semiconductor electrode composed of semiconductor nanoparticles and an electrolyte layer between a pair of transparent conductive substrates, a transparent conductive substrate at the light-receiving side is made by stacking a transparent substrate, conductive wiring layer and a metal oxide layer in order from the light-receiving side and having sheet resistance equal to or lower than 10 Ω / □. The metal oxide layer is made of an In—Sn composite oxide, SnO2, TiO2, ZnO, or the like.

In a photoelectric conversion device using a semiconductor electrode composed of semiconductor nanoparticles, the semiconductor electrode is made by coating and drying a paste containing a binder and semiconductor nanoparticles dispersed therein on a transparent conductive substrate, and pressing the paste to bond the semiconductor nanoparticles onto the transparent conductive substrate while heating it to a temperature in the range from 30° C. to the softening temperature of the transparent conductive substrate, or, if the semiconductor nanoparticles retain a sensitizing dye, to a temperature in the range from 30° C. to lower one of the softening temperature of the transparent conductive substrate and the deactivation temperature of the sensitizing dye.

A method for synthesis of high quality colloidal nanoparticles using comprises a high heating rate process. Irradiation of single mode, high power, microwave is a particularly well suited technique to realize high quality semiconductor nanoparticles. The use of microwave radiation effectively automates the synthesis, and more importantly, permits the use of a continuous flow microwave reactor for commercial preparation of the high quality colloidal nanoparticles.

The present invention provides 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 comprising bringing a dispersion of III-V semiconductor nanoparticles in an organic solvent into contact with an aqueous solution of a Group II element-containing compound and a Group VI element-containing compound to thereby transfer the III-V semiconductor nanoparticles of the organic solvent dispersion to the aqueous solution, and then irradiating the aqueous solution with light; and a method of producing a glass matrix having the nanoparticles dispersed therein.The present invention provides III-V semiconductor nanoparticles having a high photoluminescence efficiency in an aqueous solution, and a method of producing the nanoparticles. The invention further provides a fluorescent material with high PL efficiency containing the III-V semiconductor nanoparticles retained in a glass matrix, a method of producing the fluorescent material, and a light-emitting device containing the fluorescent material.

A high temperature (on the order of about 90° C. or above) non-aqueous synthetic procedure for the preparation of substantially monodisperse IV-VI semiconductor nanoparticles (quantum dots) is provided. The procedure includes first introducing a first precursor selected from the group consisting of a molecular precursor of a Group IV element and a molecular precursor of a Group VI element into a reaction vessel that comprises at least an organic solvent to form a mixture. Next, the mixture is heated to a temperature of about 90° C. or above and thereafter a second precursor which is different from the first precursor and is selected from the group consisting of a molecular precursor of a Group IV element and a molecular precursor of a Group VI element is added into the heated mixture. The reaction mixture is then mixed to initiate nucleation of IV-VI nanocrystals and the temperature of the reaction mixture is controlled to provide substantially monodispersed IV-VI nanoparticles having a diameter of about 20 nm or less.

A plurality of semiconductor nanoparticles having an elementally passivated surface are provided. These nanoparticles are capable of being suspended in water without substantial agglomeration and substantial precipitation on container surfaces for at least 30 days. The method of making the semiconductor nanoparticles includes reacting at least a first reactant and a second reactant in a solution to form the semiconductor nanoparticles in the solution. A first reactant provides a passivating element which binds to dangling bonds on a surface of the nanoparticles to passivate the surface of the nanoparticles. The nanoparticle size can be tuned by etching the nanoparticles located in the solution to a desired size.

The invention provides a semiconductor nanoparticle comprising a semiconductor nanoparticle core on the surface of which electron-releasing groups are arranged, the semiconductor nanoparticle having a fluorescent property and water-solubility. The invention also provides a water-soluble semiconductor nanoparticle with an excellent fluorescent property that can be easily prepared by adding a surface-treating material for providing a semiconductor nanoparticle with one or more kinds of electron-releasing groups, and arranging the electron-releasing groups on the surface of the semiconductor nanoparticle core.

The present relates in general to upconversion luminescence (“UCL”) materials and methods of making and using same and more particularly, but not meant to be limiting, to Mn2+ doped semiconductor nanoparticles for use as UCL materials. The present invention also relates in general to upconversion luminescence including two-photon absorption upconversion, and potential applications using UCL materials, including light emitting diodes, upconversion lasers, infrared detectors, chemical sensors, temperature sensors and biological labels, all of which incorporate a UCL material.

A method for synthesis of high quality colloidal nanoparticles using comprises a high heating rate process. Irradiation of single mode, high power, microwave is a particularly well suited technique to realize high quality semiconductor nanoparticles. The use of microwave radiation effectively automates the synthesis, and more importantly, permits the use of a continuous flow microwave reactor for commercial preparation of the high quality colloidal nanoparticles.

The present invention relates to a formulation for use in the fabrication of a light emitting device said formulation comprising a population of semiconductor nanoparticles incorporated into a plurality of discrete microbeads comprised of an optically transparent medium, said nanoparticle-containing medium being embedded in a host light emitting diode encapsulation medium. A method of preparing such a formulation is described. There is further provided a light emitting device including a primary light source in optical communication with such a formulation and a method of fabricating the same.