487 results about "Alloy nanoparticle" patented technology

Nanoparticles of silicon oxide alloys (i.e., oxides of SiMo, SiPt, and SiAl) are produced by laser vaporization of a silicon target and a target of a metal (i.e., Mo, Pt, or Al), in an oxygen containing atmosphere in a diffusion cloud chamber, where the target metal vapors aggregate into novel three-dimensional porous web structures. The structures have a homogeneous composition with a uniform ratio of silicon to the metal.

Methods for making metal-based nanoparticles and inks are disclosed. In accordance with the method of the present invention, molecular metal precursors are reduced in the presence of a reaction medium to form the nanoparticles. The molecular metal precursors are preferably reduced by heating the metal precursor in the medium, by adding a reducing agent, such an aldehyde or a combination thereof. Metal precursor are preferably metal oxides, transition metal complexes or combination thereof. The method of the present invention is used to make high yield nanoparticles with a range of particle size distributions. Nanoparticle formed by the present invention include mixtures of nanoparticle, alloy nanoparticles, metal core shell nanoparticles or nanoparticle comprising a single metal species.

The present teachings are directed toward single metal and alloy nanoparticles and synthesis methods for preparing single metal and alloy nanoparticles.

An anode material made from nanoparticles, said anode material including a homogeneous mixture of lithium-alloying nanoparticles with active support matrix nanoparticles, is provided. The active support matrix nanoparticle is a compound that participates in the conversion reaction of the lithium battery. The compound is preferably a transition metal compound, with said compound including a nitride, carbide, oxide or combination thereof.

An electrode manufactured from the anode material preferably has a porosity of between 5 and 80% and more preferably has a porosity between 10 and 50%. The anode material nanoparticles preferably have a mean linear dimension of between 2 and 500 nanometers, and more preferably have a mean linear dimension of between 2 and 50 nanometers.

The PCB manufactured by spraying conductive ink dispersed with Ag—Pd alloy nanoparticles and curing to form wiring according to the present invention provides reduced migration of Ag ions. Further, the present invention provides a method for manufacturing PCB which exhibits competitive price, and excellent conductivity and anti-migration. As one aspect of the present invention, a conductive ink comprising Ag—Pd alloy nanoparticles, wherein the Ag—Pd alloy nanoparticles includes Pd in the range of from 5 weight % to 40 weight %.

The invention discloses a core-shell structure catalyst for fuel cells and its pulse electrodeposition preparation method. The active component of the catalyst is a nanoparticle with a core-shell structure, and an active metal is cladded in the form of an ultrathin shell on the surface of a carbon carrier loaded metal or alloy nanoparticle serving as a core. The catalyst takes a non-platinum noble metal or transition metal as the core, and adopts more than one of Pt, Ir or Au as the shell. The preparation method includes: preparation of the nanoparticle serving as the core, making of a working electrode for pulse electrodeposition, and preparation of the catalyst by pulse electrodeposition. The catalyst can be used as an anode or cathode catalyst of a low temperature fuel cell. The obtained catalyst has very high stability. Compared with underpotential deposition, the method is simple to operate, has no need for inert atmosphere protection, and is more suitable for large-scale industrial production, also can greatly reduce the noble metal consumption of fuel cells, and greatly reduce the cost of fuel cells, thus having great significance in promoting the commercialization process of fuel cells.

Monodisperse core-shell types of metal, metal oxide, and alloy nanoparticles with variable core diameters and shell thicknesses, and controlled synthesis methods for producing such nanoparticles are provided. Nanocomposite materials fabricated from nanoparticles, and methods for producing such nanocomposite materials are also provided.

The invention provides a nitrogen-doped porous vertical graphene nanowall array. A compact coating layer is formed by means of nickel hydroxide serving as a template and the self-assembly property of dopamine, then high-temperature carbonization is conducted to prepare a nitrogen-doped vertical graphene nanowall array material, in-situ functional modification is conducted on the basis, the compound functional material loaded with noble metal nanoparticles, noble metal alloy nanoparticles, metal oxides, metal sulfide, metal phosphide, conductive polymers and the like is obtained, and application in the fields of supercapacitors, lithium ion batteries, water decomposition, electrochemical catalysis, enzyme-free biosensors and the like is explored.

Methods and assemblies for the construction of liquid-phase alloy nanoparticles are presented. Particle formation is directed by molecular self-assembly and assisted by sonication. In some embodiments, eutectic gallium-indium (EGaIn) nanoparticles are formed. In these embodiments, the bulk liquid alloy is ultrasonically dispersed, fast thiolate self-assembly at the EGaIn interface protects the material against oxidation. The assembly shell has been designed to include intermolecular hydrogen bonds, which induce surface strain, assisting in cleavage of the alloy particles to the nanoscale. X-ray diffraction and TEM analyses reveal that the nanoscale particles are in an amorphous or liquid phase, with no observed faceting.

Platinum (Pt)-based alloys are effective catalysts for oxygen reduction reaction (ORR) or fuel oxidation in proton exchange membrane fuel cells (PEMFCs). A wet-chemical approach for preparing monodisperse Pt₃Ni, Pt₃Co and Pt₃Fe nanocubes and Pt₃Ni nanoctahedra which are terminated with {100} and {111} facets, respectively, were developed. Such nanoscaled electrocatalysts supported on carbon black with controlled shape, e.g., octahedral configuration, is provided. ORR activity on the Pt₃Ni nanoctahedra is ˜5.1 fold higher than that of nanocubes with a similar size, and their C-supported samples are highly active with respect to commercial Pt/C.

A method is featured for fabricating Carbon-supported AuPt nanoparticle catalysts for fuel cells, and particularly fuel cells using methanol as the fuel. The method prepares AuPt-based fuel cell catalysts having a wide range of controllable Au:Pt ratios. The AuPt catalysis are supportable on both carbon black (C) and C/TiO₂ support materials. These materials demonstrate electro-catalytic activity towards CO and methanol oxidation, and O₂ reduction. The same catalyst material is useful in constructing both anodes and cathodes, and demonstrates bifunctional activity.

The invention relates to a method for preparing a high-dispersion precious metal and alloy nanoparticles thereof, which comprises: 1) uniformly stirring glycol and specific surfactant in a certain proportion in an inert atmosphere to prepare milky emulsion; 2) adding solution of precursor of the precious metal into the mixed solution, heating the resulting solution to a given temperature, keeping the temperature for a certain time period with stirring, cooling to room temperature, adding nonpolar solution and extracting; and 3) performing the rotary evaporation of upper solution to remove solvent, washing with ethanol or mixed solution of ethanol and normal hexane, centrifuging and obtaining the high-dispersion precious metal and the alloy nanoparticles thereof. The nanoparticles prepared by the method have uniform particle size and high monodispersity, and can be separated easily; the alloy is controllable in particle size and composition; the process is simple; the preparation cost is low; the solvent system is cheap; and the method is widely applicable and can realize large-scale preparation easily.

The invention relates to Sn—Cu—Ag alloy nanoparticles, preparation method thereof and ink or paste using the alloy nanoparticles in which the alloy nanoparticles are suitable for metal ink having excellent electrical conductivity or solder materials having low calcinating temperature.

The invention discloses a preparation method for carbon nano tube surface loaded magnetic alloy nano particle composite material, which belongs to the field of electromagnetic wave absorbing material preparation. The preparation method comprises the following steps: after purifying and activating a carbon nano tube, evenly dispersing the carbon nano tube to chloride salt solution of iron, cobalt and nickel, slowing adding an alkali solution dropwise into the solution in the fierce agitation process, and regulating the pH value of the solution and making iron ions, cobalt ions and nickel ions be coprecipitated onto the surface of the carbon nano pipe in the form of hydroxide according to the alloy proportion set when the solution is prepared; taking out a deposit by centrifugation or filtering; and after drying the deposit, carrying out the heat treatment of the deposit in the reducing atmosphere to obtain the carbon nano tube composite material loaded with magnetic alloy particles. The preparation method adopts a simple process. As no impurity element is introduced into the preparation process, the obtained magnetic alloy particles have high degree of crystallinity and excellent magnetic properties. In addition, the method has easy regulation of the alloy components. The composite material prepared by the method is significantly applied in the fields of electromagnetic interference resistance, stealth, microwave darkrooms, and the like.

The invention discloses alloy nanoparticles, a preparation method and applications thereof. According to the method, a metal precursor loaded on a substrate is rapidly reduced at a high temperature, wherein the metal is rapidly nucleated to avoid the generation of the split-phase alloy so as to form the alloy nanoparticles with ultra-small particle size; and by controlling the types of the metal salts in the precursor, the components in the alloy nanoparticles can be effectively regulated. According to the present invention, the FeCoPtPdIr@GO (FeCoPtPdIr alloy particles are loaded on the surface of graphene oxide) prepared in the embodiments of the invention shows excellent electrochemical hydrolysis hydrogen production performance, can stably operate for 150 h under a condition of 10 mA.cm<-2>, has excellent electrochemical stability, and has the Faraday efficiency of 99.4%, wherein the eta 10 of the product of the present invention is equal to 42 mV, and far exceeds the eta 10 of thecommercial Pt/C of 64 mV (the smaller the eta 10, the better the electrochemical hydrolysis hydrogen production performance); and the new thought is provided in the preparation of alloy nanoparticlesand alloy nanometer catalysts, and the development of alloy nanometer catalysts in catalysis and energy is promoted.

This invention provides Cu-Ag alloy conductor slurry and its manufacturing method including: preparing nm particles of Cu-Ag alloy, matching conductor slurry and sintering the slurry, in which, the nm particles are prepared under the mixed atmosphere of H and Ar with the DC arc plasma method and the preparation for the slurry includes: fully mixing terpinyl, EC and absolute alcohol then adding nm particles and fully beating them up to be vibrated by supersonic waves then to be added with glass power to beat them up again and vibrate them with supersonic waves to get the conductor slurry. The sinter temperature is bellow 220deg.C under 1.33Pa. Advantage: the sinter temperature is low not needing protection gas while sintering, the conductive stability is higher than Cu power slurry and ití»s possible to replace Au, Ag and Pd slurry.

The present invention discloses a palladium alloy catalyst, a preparation method and applications thereof, wherein the palladium alloy catalyst is alloy nanoparticles formed from a palladium element and a base metal element, and the surface of the alloy nanoparticles has a porous structure. According to the present invention, by introducing the base metal into the palladium metal, the palladium metal content is effectively reduced, the economic cost of the palladium alloy catalyst is effectively reduced, the palladium metal provides the synergistic effect with the base metal, and the palladium alloy catalyst can have high catalytic activity and high stability through the porous structure on the surface; and with the method, the advantages of effectively-reduced catalyst production cost, energy source saving, environment protection and mass-production can be provided.