3976 results about "Metal nanoparticles" patented technology

The present invention comprises methods and compositions comprising metal nanoparticles. The invention comprises metal nanoparticles and surfaces treated with a metal nanoparticle coating. The present invention further comprises compositions for preparing nanoparticles comprising at least one stabilizing agent, one or more metal compounds, at least one reducing agent and a solvent. In one aspect, the stabilizing agent comprises a surfactant or a polymer. The polymer may comprise polymers such as polyacrylamides, polyurethanes, and polyamides. In one aspect, the metal compound comprises a salt comprising a metal cation and an anion. The anion may comprise saccharinate derivatives, long chain fatty acids, and alkyl dicarboxylates.

Compositions for use in ink jet printing onto a substrate comprising a water based dispersion including metallic nanoparticles and appropriate stabilizers. Also disclosed are methods for the production of said compositions and methods for their use in ink jet printing onto suitable substrates.

Disclosed is a method for producing core-shell type metallic nanoparticles involving (i) providing a dispersion of a first metal as nanoparticles in an appropriate organic solvent; (ii) providing a solution of a metallic precursor containing a second metal in an appropriate organic solvent, in which the second metal has a reduction potential higher than that of the first metal; and (iii) combining the dispersion from (i) and the solution from (ii) together to carry out the transmetalation reaction of the first and second metals, thereby forming core-shell type metallic nanoparticles.

The present invention relates to methods of making and using and compositions of metal nanoparticles formed by green chemistry synthetic techniques. For example, the present invention relates to metal nanoparticles formed with solutions of plant extracts and use of these metal nanoparticles in removing contaminants from soil and groundwater and other contaminated sites. In some embodiments, the invention comprises methods of making and using compositions of metal nanoparticles formed using green chemistry techniques.

A process for preparing metal nanoparticles, comprising reacting suitable metal salts and anionic surfactant containing an anionic group of carboxylic group (COO-), sulfate group (SO42-) or sulfonate group (SO32-) as reducing agent in water under reflux at a temperature of 50-140° C., such that under the reducing power of said anionic surfactant itself, the metal salts can be effectively reduced into metal nanoparticles having a uniform particle size and that the reaction will be not too fast, no large microparticle will be formed, the yield will not be lowered, and the nanoparticle thus prepared can be dispersed stably in polar and non-polar solvent.

Optically transparent, conductive polymer compositions and methods for making them are claimed. These conductive polymer compositions comprise an oxidized 3,4-ethylenedioxythiopene polymer, a polysulfonated styrene polymer, single wall carbon nanotubes and/or metallic nanoparticles. The conductive polymer compositions can include both single wall carbon nanotubes and metallic nanoparticles. The conductive polymer compositions have a sheet resistance of less than about 200 Ohms/square, a conductivity of greater than about 300 siemens/cm, and a visible light (380-800 nm) transmission level of greater than about 50%, preferably greater than about 85% and most preferably greater than about 90% (when corrected for substrate). The conductive polymer compositions comprising single wall carbon nanotubes are made by mixing the oxidized 3,4-ethylenedioxythiopene polymer and polysulfonated styrene polymer with single wall carbon nanotubes and then sonicating the mixture. The conductive polymer compositions comprising metallic nanoparticles are made by a process of in situ chemical reduction of metal precursor salts.

A process for the production of metal nanoparticles. Nanoparticles are formed by combining a metal compound with a solution that comprises a polyol and a substance that is capable of being adsorbed on the nanoparticles. The nanoparticles are precipitated by adding a nanoparticle-precipitating liquid in a sufficient amount to precipitate at least a substantial portion of the nanoparticles and of a protic solvent in a sufficient amount to improve the separation of the nanoparticles from the liquid phase.

The invention discloses a preparation method of a textured structure of a crystalline silicon solar cell. The method includes the steps of (1) cleaning and texture preparation, (2) soaking a silicon wafer in a solution containing metal ions to enable the surface of the silicon wafer to be coated with a layer of metal nanometer particles, (3) corroding the surface of the silicon wafer to form a nanometer-grade texture, (4) cleaning to remove the metal particles, (5) carrying out microstructure amendment etching in second chemical corrosive liquid, and (6) cleaning and spin-drying. As is proved by a test, the size of the textured structure is between 100nm-500nm; the textured structure is of a nanopore shape with a large hole diameter and a small depth, or a nanometer pyramid with edge angles, or of a nanometer pit shape structure with an edge angle nanometer cone body or with an edge angle; and compared with a nanometer-micrometer composite textured structure disclosed in CN102610692A, the textured structure enables conversion efficiency of a cell piece to be improved by about 0.2%-0.5%, and an unexpected effect is achieved.

A new class of microwires and a method for their assembly from suspensions of metallic nanoparticles in water under the influence of dielectrophoretic forces. The wires are formed in the gaps between planar electrodes in an alternating current (AC), allowing manipulation of the particles without the interference of electro-osmotic and electro-chemical effects resent in direct current (DC) systems. The structures created cover a new size domain of microwires of micrometer diameter and millimeter to centimeter length, closing the gap between tradition metallic wires and the more recently synthesized nanowires and carbon tubes. The wires have good Ohmic conductance and their thickness, conductivity, and fractal dimension can be controlled by varying the frequency and voltage of the applied field. The formation of such self-assembled structures can be used in miniaturization of electrical circuits for application in sensors, memory elements, and wet electronic circuits, such as electrically readable bioarrays and biological-electronic interfaces.

The present invention relates to a method for effectively delivering an anticancer drug into cancer cells by binding the anticancer drug to pH-sensitive metal nanoparticles so as to be separated from cancer cells. The pH-sensitive metal nanoparticles according to the present invention may be heated by photothermal therapy, thereby effectively killing cancer cells in conjunction with the isolated anticancer drug.

An inorganic material that consists of at least two elementary spherical particles, each of said spherical particles comprising metal nanoparticles that are between 1 and 300 nm in size and a mesostructured matrix with an oxide base of at least one element X that is selected from the group that consists of aluminum, titanium, tungsten, zirconium, gallium, germanium, tin, antimony, lead, vanadium, iron, manganese, hafnium, niobium, tantalum, yttrium, cerium, gadolinium, europium and neodymium is described, whereby said matrix has a pore size of between 1.5 and 30 nm and has amorphous walls with a thickness of between 1 and 30 nm, said elementary spherical particles having a maximum diameter of 10 μm. Said material can also contain zeolitic nanocrystals that are trapped within said mesostructured matrix.

The invention relates to a method for preparing a nanocomposite by using two-dimensional transition metal chalcogenide nanosheets and metal, and belongs to the field of nanomaterial synthesis. The method mainly includes adding a reducing agent and a stabilizing agent into monolayer or multi-layer two-dimensional transition metal chalcogenide nanosheet aqueous dispersion obtained after chemical intercalation, then injecting a certain amount of metal salt solution, and preparing the metal nanocomposite based on monolayer or few-layer two-dimensional transition metal chalcogenide nanosheets on the conditions of ice bath, hydrothermal method, microwaves, ultrasound and the like. In the composite, metal nanoparticles can be evenly distributed on the surfaces of the nanosheets, and the obtained composite can be evenly dispersed in water, and can be used in the solution phase and further processed. Through compositing of the metal nanoparticles, photoelectric property of two-dimensional transition metal chalcogenide can be improved, and the nanocomposite has good application prospects in the fields of supercapacitors, fuel cells and biosensors based on surface enhanced Raman detection, and the like.

The invention discloses a SERS biological probe and a preparation method thereof. The SERS biological probe provided by the invention comprises a SiO2 core and a metal nanoparticle layer on the surface of the SiO2 core, wherein a plurality of Raman signal molecules connected with the metal nanoparticle layer; a SiO2 layer is also provided outside the metal nanoparticle layer; the Raman signal molecules are positioned between the metal nanoparticle layer and the SiO2 layer; the SiO2 layer surface is modified with biological probe molecules; and the metal nanoparticle layer is Au nanoparticle layer or Ag nanoparticle layer. The SERS biological probe provided by the invention has wide generality, and has wide application prospect in identification and detection of biological molecules (DNA molecules and protein molecules), rapid disease diagnosis, biomedical imaging technology as well as in the fields of serious disease treatment, food hygiene, environmental monitoring, etc.

Compositions having antimicrobial activity contain particles comprising at least one inorganic copper salt; and at least one functionalizing agent in contact with the particles, the functionalizing agent stabilizing the particle in a carrier such that an antimicrobially effective amount of ions are released into the environment of a microbe. The average size of the particles ranges from about 1000 nm to about 3 nm. Preferred copper salts include copper iodide, copper bromide and copper chloride, most preferred being copper iodide. Preferred functionalizing agents comprise materials with a molecular weight of 60 or above, which include amino acids, other acidic materials, thiols, hydrophilic polymers, emulsions of hydrophobic polymers and surfactants. The functionalized particles are preferably made by a grinding process.

A method of producing metal nanoparticles in a high yield rate and uniform shape and size, which is thus suitable for mass production. In addition, metal nanoparticles are provided that have superior dispersion stability when re-dispersed in various organic solvents, which thus suitable for use as a conductive ink having high conductivity. The method of producing nanoparticles includes mixing a metal precursor with a copper compound to a hydrocarbon based solvent, mixing an amine-based compound to the mixed solution of the metal precursor with copper compound and hydrocarbon based solvent, and mixing a compound including one or more atoms having at least one lone pair, selected from a group consisting of nitrogen, oxygen, sulfur and phosphorous to the mixed solution of the amine-based compound, metal precursor with a copper compound and hydrocarbon based solvent.

The invention belongs to the technical field of molecular sieve preparation, and particularly relates to an in-situ preparation method for a microporous-mesoporous molecular sieve containing noble metal. The in-situ preparation method comprises the steps as follows: adding a coupling pore-forming agent, a silicon source, an aluminum source or a titanium source, and an alkali source into a water solution of noble metal nano particles in sequence under the water bath condition; and ageing, drying, crystallizing, drying and carrying out high-temperature calcination to obtain the microporous-mesoporous molecular sieve containing the noble metal. The prepared microporous-mesoporous molecular sieve is provided with a hierarchical pore structure; the noble metal nano particles with high dispersity are covered in situ while a mesoporous structure is generated; and a synthetic method is convenient and simple, saves energy and reduces emission. A multifunctional catalyst prepared with the method integrates the advantages of the microporous channels of the molecular sieve, the transgranular meso pores and the intergranular meso pores of the molecular sieve and the noble metal nano particles, and is more suitable for catalytic reactions of sulfur-containing large molecules such as hydrogen desulfurization and the like.

Provided is a method for the formation of metallic nanoparticles which involves forming a solution which contains metal ions and polymers having both reducing components and stabilizing components, such that metal nanoparticles are formed. Also provided is a suspension of nanoparticles which are formed by the method.