30results about How to "Catalytic activity does not decay" patented technology

The invention relates to a nitrogen-doped graphene-ferronickel hydrotalcite non-noble metal difunctional oxygen catalyst and a preparation method thereof and electrocatalysis application of the oxygen catalyst in an alkaline medium to an oxygen evolution reaction and an oxygen reduction reaction. According to the catalyst, a micelle is taken as a template, ferronickel hydrotalcite is assembled on graphene oxide under the hydrothermal condition to form a spherical porous compound, the graphene oxide is reduced and doped with a nitrogen carbide nanosheet simultaneously under the hydrothermal condition, and then the nitrogen-doped graphene-ferronickel hydrotalcite oxygen catalyst is obtained. The method comprises the steps that the graphene oxide and metal salt are firstly dispersed into the micelle, the graphene oxide-ferronickel hydrotalcite compound is obtained through hydro-thermal synthesis under the alkaline condition, the product is doped with the nitrogen carbide nanosheet under the hydrothermal condition, and then the oxygen catalyst is obtained. The oxygen catalyst has the catalytic activity both on oxygen evolution and oxygen reduction under the alkaline condition and is high in stability and methyl alcohol tolerance, low in used raw material cost, simple in preparation method and convenient for scale production.

The invention provides a biomass carbon/ferrocobalt dual-metal-oxide double-functional oxide catalyst as well as a preparation method and application thereof. The catalyst takes sodium alginate as a template; metal ions are firstly captured on sodium alginate molecules and a sodium alginate/ferrocobalt type hydrotalcite compound is prepared under an alkaline condition; and then the biomass carbon/ferrocobalt dual-metal-oxide double-functional oxide catalyst is prepared through high-temperature calcining. In the oxide catalyst provided by the invention, double metal oxides exist in the forms of CoO, Co3O4, FeO and Fe2O3, and less monomer Co is included. Therefore, the catalyst has high oxygen evolution (OER) and oxygen reduction (ORR) catalytic activities, good stability and excellent methanol tolerance under the alkaline condition; and the catalyst has the advantages of low cost of the used raw materials, simple preparation method, easiness in operation and convenience for large-scale production.

The invention discloses a high-performance alkaline fuel cell cathode carbon catalyst and a preparation method of the high-performance alkaline fuel cell cathode carbon catalyst. The catalyst disclosed by the invention is a composite carbon material in a core-shell nanostructure, which is prepared by adulterating two elements of Fe and N, using conductive carbon black with a high-ratio surface as an inner core and coating a phthalocyanine iron shell around the inner core. The preparation method comprises the following steps of: weighing and mixing phthalocyanine iron solid powder and the conductive carbon black with the high-ratio surface according to a certain mass ratio, and then preparing to obtain a C@FePc carbon non-noble metal catalyst in the core-shell nanostructure by adopting a simple mechanical ball milling method. The catalyst disclosed by the invention has high-performance oxygen reduction reaction (ORR) catalytic activity, excellent CH3OH/CO tolerance and good stability, the cost of raw materials used in the preparation process is low, the operation is simple and convenient, and the catalyst is easy for large-scale commercialized production.

The invention relates to a method for preparing a graphene/nickel-iron hydrotalcite nano-sheet bifunctional oxygen catalyst by a one-step process, and an electrocatalytic application thereof in an oxygen evolution reaction and an oxygen reduction reaction in an alkaline medium. Graphene oxide is as a substrate, ultrathin nickel-iron hydrotalcite nano-sheets in situ grow in a formamide and water mixed solution, and thermal reduction is carried out to prepare the graphene/nickel-iron hydrotalcite nano-sheet composite oxygen catalyst. The method avoids the steps of hydrotalcite-like peeling and chemical reduction of graphene oxide, increases the active sites of the catalyst, inhibits aggregation of graphene and nickel-iron hydrotalcite nano-sheets in the compound, and improves the conductivity of the compound; and the obtained catalyst reduces the overpotential of oxygen evolution and oxygen reduction reactions in the alkaline medium, reduces the electron transfer resistance, has good oxygen catalytic performance and stability, and provides a great way for the development of potential bifunctional oxygen catalysts.

The invention relates to a MoS2 nanosphere difuncitonal oxygen catalyst of a hierarchy structure a preparation method thereof and application thereof in electrocatalyzing oxygen in an alkaline medium. The MoS2 nanosphere difuncitonal oxygen catalyst is MoS2 nanospheres which are synthesized by taking Na2MoO4 and KSCN as raw materials and adopting a hydrothermal method and have the hierarchy structure, and the MoS2 nanospheres are formed by a plurality of MoS2 nanosheets, so that the MoS2 nanospheres have a large specific surface area, and edge sits of the MoS2 nanosheets are fully exposed. Due to multiporous flower-shaped nanospheres formed by ultra-thin MoS2 nanosheet units, the effective electrochemical catalysis area and the catalytic sites are increased, and the electron conduction rate is quickened, so that overpotential of an oxygen evolution reaction and an oxygen reduction reaction can be effectively reduced; a rotating disk electrode and a rotating ring disk electrode show that the oxygen reduction process is based on a four-electron catalytic mechanism and is a relatively ideal oxygen reduction reaction process.

The invention relates to the technical field of water electrolysis catalytic materials, in particular to a preparation method of an Ag-coated CoMoO4 oxygen evolution electrocatalyst. Comprising the following steps: (1) mixing polyvinylpyrrolidone with 1, 2-propylene glycol, stirring at a certain temperature, and then adding a sodium chloride solution and a silver nitrate solution with a certain concentration to prepare a silver nanowire solution; (2) purifying the silver nanowires with acetone and washing the silver nanowires for several times for later use; (3) weighing 2-methylimidazole, adding 2-methylimidazole into a mixed solution of different amounts of silver nanowires and methanol, adding a methanol solution of cobalt nitrate hexahydrate, dissolving the mixed solution in ethanol, and stirring at normal temperature; (4) adding sodium molybdate nonahydrate into the product obtained in the step (3), and carrying out hydrothermal reaction; after naturally cooling to room temperature, centrifugally collecting, washing with ethanol for multiple times, and drying to obtain the catalyst; the production cost is low, large-scale production is easy to achieve, the microstructure and good catalytic activity can be kept for a long time under the alkaline condition, and potential industrial application value is achieved in the aspect of electro-catalytic hydrogen production.

The invention relates to a mining quick-plugging polyurethane foam material and a preparation method thereof, and belongs to a mining polymer material. According to the technical scheme, the materialis composed of a component A combined material and a component B combined material, the method includes filling a metal steel cylinder A and a metal steel cylinder B with the component A combined material and the component B combined material respectively; respectively inflating nitrogen into the two metal steel cylinders A and B for pressurization and controlling the pressure in the metal steel cylinder A to be 2.0 to 2.1 Mpa and the pressure in the metal steel cylinder B to be 2.1-2.2 Mpa; mixing and spraying the material A and the material B through spray guns according to a mass ratio of 1: 1 and a ratio that the reaction group molar ratio of -NCO to -OH is 1.09-1.25:1, and mixing the material A and the material B through spray heads of the spray guns to form the quick-plugging polyurethane foam material for mining. According to the invention, the polyurethane foam formed by spraying has good toughness and bonding strength, and the plugging and sealing effects are enhanced.

The invention discloses a metal-N4-doped carbon catalyst with high oxygen reduction performance and a preparation method thereof, the metal-N4-doped carbon catalyst is a transition metal and nitrogen element-doped two-dimensional carbon nanosheet, the carbon catalyst has a porous lamellar nanostructure, all metal species in the carbon catalyst are an Me-N4 structure composed of atomic transition metal and N4, and Me-N4 is an active site. Wherein Me is at least one metal of Fe, Co, Ni, Cu, Zn and Mn. The method comprises the following steps: adding three compound precursors of metal phthalocyanine, phthalocyanine and zinc salt into a liquid solvent according to a set mass ratio, uniformly mixing, continuously heating until the liquid solvent is completely volatilized, and preparing the metal-N4 doped non-noble metal carbon catalyst by adopting a one-step high-temperature pyrolysis method. The catalyst disclosed by the invention has high oxygen reduction reaction (ORR) catalytic activity, excellent CH3OH/CO tolerance and good stability; the preparation process is simple and easy to control, the used raw materials are commercially available products, and batch production can be realized.