112 results about "Transition metal nanoparticles" patented technology

The invention relates to a set of electrocatalytic strong oxidizer materials, comprising a nano-function anode material which compounds nano oxide particles and catalyzes metal nano particles on a titanium substrate, and a nano-function cathode material which takes titanium or stainless steel as a substrate and introduces transition metal nano-particles on the surface thereof. By the electro-catalytic advanced oxidation technology, under the catalytic action of electrocatalytic strong oxidizer materials, water body can generate a hydroxyl radical with strong oxidizing performance and an oxygen radical; and if a chloride ion exists in water, hypochlorite can be generated. Under the joint action of a plurality of types of strong oxidizers, the algae cells in the water body and various harmful bacteria can be killed; and simultaneously the ammonia in water and the water-soluble organic matters can be degraded, so the goal of purifying water is achieved. According to the electrocatalytic advanced oxidation theory, the electrocatalytic strong oxidizer materials does not need to add any chemical agent when in application, does not have secondary pollution, and has good safety, high efficiency and low energy consumption.

The present invention features a method for preparing core-shell nanoparticles supported on carbon. In particular, the present invention features a method for preparing core-shell nanoparticles supported on carbon, including: dispersing core nanoparticle powder supported on carbon in ethanol; adding a metal precursor which forms a shell and hydroquinone thereto; and mixing and reducing the same. Preferably, the disclosed method for preparing core-shell nanoparticles supported on carbon enables coating of transition metal nanoparticles including platinum on the surface of core metal nanoparticles at a monolayer level. Prepared core-shell nanoparticles of the present invention may be useful as catalysts or electrode materials of fuel cells.

The invention relates to a preparation method for a transition metal oxide nanoparticle. The preparation steps include: adding one of a soluble cobalt salt, manganese salt, copper salt and nickel salt or a mixture of the two into water or ethanol, and dispersing the materials uniformly, then adding an amino group-containing small molecular alkali or alkaline solvent, placing the mixed solution into an oil bath pan to conduct heating reflux till generation of solid precipitate, when the precipitate no longer increases, performing cooling, and subjecting the solid precipitate to filtering, washing and drying so as to obtain the transition metal oxide nanoparticle. The method provided by the invention has the advantages of simplicity and practicability, and convenient mass production. At the same time, the transition metal nanoparticle prepared by the method has the characteristics of even particle size, and good catalytic activity and stability, and is suitable for use as an oxygen reduction reaction catalyst in fuel cells, metal air batteries and the like.

The invention discloses a transition metal-nitrogen doped carbon composite material and a preparation method thereof. Transition metal chlorine salt and nitrogenous small organic molecules serve as atransition metal source and carbon and nitrogen sources, and transition metal coordinated macro-cyclic mixture is directly obtained by a one-step method and then carbonized to obtain the transition metal-nitrogen doped carbon composite material. The preparation method is simple, convenient, rapid and suitable for large-scale production and preparation, the synthesized transition metal-nitrogen doped carbon composite material structures a nano-sheet, transition metal on the nano-sheet exists in two forms, one form is transition metal nanoparticles, and the other form is transition metal nitridenanoparticle. The synthesized transition metal-nitrogen doped carbon composite material has nitrogen doped carbon, transition metal and nitrogen atom coordinated active sites with more defects, has large specific surface area and can be applied to the field of catalysis and energy storage.

Disclosed is an energy storage device based on metal oxide nanocrystals resealed through lithiation, and a supercapacitor using the same. The energy storage device is fabricated by dispersing transition metal nanoparticles over a carbon-based support with a large specific surface area, and then, dispersing and resealing the nanoparticles over the support using lithium ions with strong reductive ability, so that the resealed metal particles are substantially particles dispersed and resealed over the support as particles having a size of less than 1 nanometer on the scale of atomic units. The supercapacitor is fabricated using the energy storage device. The energy storage device higher capacitance than before resealing of metal oxide. Since the resealed metal particles are those having a size of less than 1 nanometer on the scale of atomic units, interference between particles disappears to exhibit excellent cycle life characteristics of 100% maintained performance in even more than 100,000 cycles.

The present invention is directed to an aggregate composed of a plurality of nanoparticles of a transition metal and a plurality of cyanine dye molecules that are interacting non-covalently. The nanoparticles are capped with a capping molecule, while the cyanine dye molecule can be cationic, anionic, or neutral cyanine dye. Methods of making such aggregates and for using them in detection of an analyte are also disclosed.

The invention relates to a supported low-platinum core-shell catalyst and a preparation method thereof. According to the method, a low-platinum core-shell catalyst with transition metals as a core andplatinum as a shell is formed through chemical replacement by taking a porous carbon skeleton supported by metal nanoparticles obtained by pyrolysis of a metal organic skeleton doped with transitionmetals (Co, Fe, Zn) as a carrier, and the composition and size of the core-shell structure can be achieved by changing the proportions of metals in the multi-metal organic framework. Compared with theprior art, the method has the following advantages: the zinc element in the prepared organic metal skeleton can be used as a barrier to prevent the formed transition metal nanoparticles from agglomerating in the pyrolysis process, and the zinc element will evaporate with the atmosphere after the temperature exceeds 900 DEG C and will not remain in the catalyst; the supported platinum is supportedon the surface of the transition metals in the form of shell in the core-shell structure, and the platinum has low load and high utilization rate; the transition metal core in the core-shell structure can change the electronic performance of the platinum surface and thus can adjust the catalytic performance; a porous carbon carrier with high specific surface is formed through pyrolysis of the organic metal skeleton, which is conducive to the uniform distribution of active sites and the mass transfer in the reaction process.

The invention discloses a carbon-coated transition metal oxide or transition metal nanoparticle (MxOy@C or M@C) composite electrode material adopting a cellular structure and a preparation method thereof, and belongs to the technical field of lithium battery preparation. Alga acid radicals and transition metal ions have a coordination reaction to produce a transition metal alginate precursor, and the precursor is burnt through control on the heating temperature under the shielding of an inert gas to obtain the MxOy@C or M@C composite electrode material adopting the cellular structure. The prepared composite electrode material has the advantages that the composite electrode material is low in preparation cost, high in specific capacity, good in circling stability, not easy to decompose and the like. For example, the specific capacities of the composite material are 500.5 mAhg-1, 478.4 mAhg-1 and 321 mAhg-1 respectively after the composite material undergoes 50 cycles under charging and discharging conditions of 100 mA, 500 mA and 1000 mA respectively.

A stable delivery system for the therapeutic release and application of nitric oxide to a patient suffering from a cutaneous injury or wound includes a S-nitrosothiol and transition element nanoparticles. The transition metal nanoparticles are selected to react with the S-nitrosothiol to release and diffuse nitric oxide into the injury or wound.

A method of producing colloidal, shaped nanoparticles of a transition metal or alloys thereof, comprising reducing ions of at least one transition metal in an aqueous solution thereof in the presence of at least one compound, which, at its isoelectric point, is a zwitterion and/or at least one small, non-polymeric anion and the nanoparticles produced thereby.

A carbon-coated transition metal nanocomposite material includes carbon-coated transition metal particles having a core-shell structure. The shell layer of the core-shell structure is a graphitized carbon layer doped with oxygen and/or nitrogen, and the core of the core-shell structure is a transition metal nanoparticle. The nanocomposite material has a structure rich in mesopores, is an adsorption/catalyst material with excellent performance, can be used for catalyzing various hydrogenation reduction reactions, or used as a catalytic-oxidation catalyst useful for the treatment of volatile organic compounds in industrial exhaust gases.

The invention provides a solvent-free template preparation method of a porous carbon-coated nanometer metal particle. A relatively good effect is shown when the obtained material is used for electrocatalytic oxygen-reduction reaction (ORR). According to the method, inorganic salt and a segmented copolymer (a flexible-rigid template) is used as dual templates, a transition metal salt-containing phenolic resin precursor is obtained by solid-phase reaction, and the porous carbon-coated transition metal (monometal and bimetal) material is obtained after thermal treatment carbonization, washing anddrying. During the synthesis process, a pore structure of a composition can be effectively controlled due to an effect of the flexible-rigid template, so that the contact area of an electrocatalyst and an electrolyte is substantially expanded, and the transition metal nanoparticles are more uniform in distribution on a carbon carrier. The method is low in cost, low in pollution and simple in treatment process, the limitation of active electrocatalyst production in industry is improved to a great extent, doping modification of heteroatoms such as nitrogen, sulfur, phosphorus and boron is further performed, and the method has wide application prospect.

The invention relates to a ruthenium-carbon catalyst. The ruthenium-carbon catalyst comprises an activated carbon carrier on which ruthenium nanoparticles and transition metal nanoparticles are loaded. According to the invention, transition metal atoms of molybdenum, tungsten, vanadium, rhenium or cobalt and the like are added, so that a modified ruthenium-carbon catalyst is prepared, and then the catalytic activity of the modified ruthenium-carbon catalyst is greatly improved and an activity restrictive bottleneck of the traditional ruthenium-carbon catalyst is broken. The modified ruthenium-carbon catalyst prepared by the invention takes difficult activation reactions of amino acid reduction, imide reduction and the like as evaluation reactions, and shows higher catalytic activity compared with a commercial ruthenium-carbon catalyst under same reaction conditions, and the yield of the modified ruthenium-carbon catalyst is improved by about 50% to 2 times to realize a green and high-efficient catalytic reaction process.

The invention discloses a preparation method of a high-dispersed transition metal nanoparticle-supported hierarchical pore zeolite aggregate. The preparation method comprises adding mixed liquid dropsof an inorganic aluminum source and a transition metal salt into an inorganic silicon source solution drop by drop, adjusting alkalinity through KOH or NaOH, carrying out stirring to obtain a transition metal-silica-alumina sol-gel solution, adding crystal gel with different crystal structures into the mixed solution, and carrying out crystallization at 80-200 DEG C for 10-48h to obtain the high-dispersed transition metal nanoparticle-supported hierarchical pore zeolite aggregate catalytic material with particle sizes of 1.5 to 2 nm. Compared with the prior art, the preparation method furthercontrols the synthesis of the hierarchical pore zeolite molecular sieve material, effectively adjusts and controls the opening degree of channels of hierarchical pore zeolite, and successfully modifies the surface of the hierarchical pore zeolite aggregate material with transition metal nanoparticles to produce the zeolite aggregate catalytic material with multiple active sites and agglomerationdifficulty. The preparation method has simple processes, is easy to operate and separate and has a certain industrial promotion use prospect and a remarkable economic value.

The invention comprises a chemical composition with the structure shown below. The composition can be polymerized or pyrolyzed, forming transition metal nanoparticles homogeneously dispersed in a thermoset or carbon composition. The size of the nanoparticles can be controlled by manipulating the number and arrangement of functional groups in the composition and by changing the conditions of the polymerization or pyrolysis. The resulting thermosets and carbon compositions have useful magnetic, electric, mechanical, catalytic and/or optical properties. wherein A is selected from the group consisting of H, wherein M is a metal selected independently from the group consisting of Fe, Mn, Ru, Co, Ni, Cr and V; wherein Rx is independently selected from the group consisting of an aromatic, a substituted aromatic group and combinations thereof; wherein Ry is independently selected from the group consisting of an aromatic, a substituted aromatic group and combinations thereof; wherein m is >=0; wherein s is >=0; wherein z is >=0; and wherein m and s are independently determined in each repeating unit.

The invention provides a hexagonal boron nitride nanosheet. The hexagonal boron nitride nanosheet is prepared from the hexagonal boron nitride nanosheet and transition metal nanoparticles loaded on the hexagonal boron nitride nanosheet. The invention also provides a preparation method of the hexagonal boron nitride nanosheet. By combining a transition metal ion coordination intercalation technology and a radiation reduction synthesis metal nanoparticle technology, BNNS loaded with metal nanoparticles is obtained by delaminating from an h-BN nanoparticle, which provides a new method for the preparation and functionalization of the BNNS. Compared with the existing delamination method, the new method has the characteristics of mild conditions, easy operation, environment friendliness and high efficiency and energy saving. Experimental results show that the method provided by the invention can obtain hexagonal boron nitride nanosheets with thickness of 1.5-3.0 nm.

The invention relates to nanometer coating material that has photochromism and sunshine controlled capability, and the manufacturing method and the application. It includes the following steps: adding aqueous solution of adulterated stannic oxide tin oxide nanometer to container, whisking and adding the solution of IB series transition metal nanometer partical and/ or adding the compound of IB series metal to gain the aqueous solution nanometer coating with photochromism and sunshine controlled capability. The mol ratio of doped chemical in stannic oxide and the tin is 0.1-20:100. The mol ratio of stannic oxide and the IB series metal element is 200:1-5:1. The invention could be coated onto surface of glass or organic material.