32results about How to "Low platinum loading" patented technology

The present invention relates to particle and nanoparticle composites useful as oxygen-reduction electrocatalysts. The particle composites are composed of a palladium or palladium-alloy particle or nanoparticle substrate coated with an atomic submonolayer, monolayer, bilayer, or trilayer of zerovalent platinum atoms. The invention also relates to a catalyst and a fuel cell containing the particle or nanoparticle composites of the invention. The invention additionally includes methods for oxygen reduction and production of electrical energy by using the particle and nanoparticle composites of the invention.

The present invention is directed to catalyst particles comprising a layered core-shell-shell structure and to a method of their manufacture. The catalyst particles have the general formula BM/IL/PM in which BM is a base metal core (selected from Co, Ni or Cu), PM is a precious metal outer shell (selected from Pt, Ir or Pd) and IL is an intermediate layer comprising a base metal/precious metal alloy with a concentration gradient of base metal to the outside PM layer. The particles of the present invention comprise a core-shell-shell structure and a substantially continuous precious metal shell layer. They find use in various catalytic applications, for example in gas-phase catalysis, in electrocatalysts for fuel cells, in catalytic converters for automobiles and in electronic or medical applications.

The invention provides a method for preparing a proton exchange membrane fuel cell electrode with high catalyst utilization ratio, which comprises the following steps: firstly, constructing a gas porous electrode having a complete electron channel, a gas channel and a proton channel; secondly, exchanging platinum cations onto perfluorosulfonic acid resin of the gas porous electrode by an ion exchange method; thirdly, reducing the platinum cations onto a carbon carrier contacted with the perfluorosulfonic acid resin by an electrochemical reduction method, thus, the proton exchange membrane fuel cell electrode with high catalyst utilization ratio is prepared. The invention has the advantages of simple process and low cost. The proton exchange membrane fuel cell electrode with high catalyst utilization ratio prepared by using the invention has the advantages of high catalyst utilization ratio, low platinum capacity, good dispersion of platinum nano-particles, controllable size, and the like, and can replace the prior commercial platinum/carbon (Pt/C) catalyst.

The invention concerns catalyst field, specific speaking, it's a Bo/C catalyst and its application. The catalyst is got by sulphur poison of Bo/C, specific steps: when mixing, dip the Bo water-soluble compound in the water to get Bo, take sulphur poison of parts, at solid restore, filter, wash and dry and so on. The catalyst can be used in the reaction of 4-ammonia benzene fen, especially in the reaction of the acid solution to produce 3-F-4-ammonia benzene fen, having best efficiency. When it reaches rate 100%, 3-F-4-ammonia benzene fen rate can reaches 91.7%. The Bo/C catalyst of the invention has high activation and high choosing feature can be used recycle, so it has high economy efficiency.

The invention discloses a Pt-M metal alloy catalyst prepared by electro-deposition in an organic system. A catalyst conductive carrier is carbon-based, and in an organic solvent, Pt-M metal alloy nanoparticles prepared by co-deposition of Pt-M metal are uniformly dispersed on a surface of the carrier by a physical loading mode; during the preparation process, a Pt source precursor and an M sourceprecursor are dissolved in the organic solvent, and the volume mole concentration of the metal precursor in a mixed solution is (1-20)mmol/L; and moreover, oxygen in the solution is discharged under protection of an inertia atmosphere, deposition under subsequent different deposition potentials is performed, and cycle voltammetry electrochemical cleaning is performed. In the catalyst disclosed bythe scheme of the invention, the purposes of further reducing the platinum-loading quantity of the prepared Pt-M metal alloy nanoparticle catalyst, improving the catalytic activity, greatly improvingthe precious comprehensive utilization efficiency, improving the oxygen-reduction performance and reducing comprehensive cost of the precious metal catalyst are achieved.

A method for forming a noble metal coating on a gas diffusion medium substantially free of ionomeric components comprising subjecting an electrically conductive web to a first ion beam having an energy not higher than 500 eV, then to a second beam having an energy of at least 500 eV, containing the ions of at least one noble metal and electrodes provided by the method.

Using self-assembly technique loads Nano granules of platinum in hydrosol of compositive Nano platinum to surface of conducting substrate of containing mercaptan functional group after modification of L-B membrane or silanization so as to realize even, tight and discontinuous distribution of Nano granules of platinum on surface of conducting substrate. Using high sintering or vacuum treatment in low temperature forms Nano platinum carried catalysis electrode in high chemical activity. Electrode produced in the invention possesses very low platinum load so as to lower cost for preparing solar battery. The invention is applicable to preparation of flexible electrode, especially suitable to electrode pair in Nano crystal sensitized solar battery.

A method for forming a patterned noble metal coating on a gas diffusion medium substantially free of ionomeric components comprising subjecting an electrically conductive web with a patterned mask overlaid thereto to a first ion beam having an energy not higher than 500 eV, and to a second beam having an energy of at least 500 eV, containing the ions of at least one noble metal and a gas diffusion electrode.

The invention belongs to the technical field of dye sensitized solar cells, in particular to a method for preparing a graphene/platinum nano counter electrode material for a dye sensitized solar cell. The method comprises the following steps of: soaking a conducting substrate on which a polyelectrolyte is adsorbed in a graphene suspension, a polyelectrolyte solution and a chloroplatinic acid solution in sequence in an electrostatic self-assembly way to form a self-assembly ultrathin film with a polyelectrolyte/graphene/polyelectrolyte/chloroplatinic acid structure on the surface of the conducting substrate under the action of electrostatic attraction; and sintering and transforming into a 'graphene/platinum nanoparticle' ultrathin film. The film can be taken as a counter electrode material for the dye sensitized solar cell. The preparation method has a simple process, the prepared counter electrode has extremely low platinum load amount, the cost of the counter electrode and the dye sensitized solar cell is greatly lowered, and the method can be applied to large-scale production of assembly line operation.

The invention discloses a platinum/alumina catalyst. The platinum/alumina catalyst is prepared from components in percentage by mass as follows: 0.05%-1.0% of platinum, 0.1%-2.0% of iron, 0.5%-5.0% ofgermanium dioxide and 92.0%-99.35% of alumina. The invention also discloses a preparation method of the platinum/alumina catalyst and an application of the platinum/alumina catalyst in synthesis of an anti-aging agent 4020 from the platinum/alumina catalyst, N-phenyl p-phenylenediamine and methyl isobutyl ketone in a fixed bed reactor. Compared with the prior art, the platinum/alumina catalyst has mild application conditions, high activity, high selectivity, long service life and relatively low price, is simple to produce and easy to industrialize and has bright application prospects and enormous economic benefits.

The invention relates to the technical field of fuel cell catalysts, and specifically provides a fuel cell anode catalyst, a preparation method thereof and a proton exchange membrane fuel cell. The fuel cell anode catalyst is at least one of molybdenum carbide@hollow carbon sphere and platinum&molybdenum carbide@hollow carbon sphere, wherein the molybdenum carbide@hollow carbon sphere represents that the surface of the hollow carbon sphere is loaded with molybdenum carbide nanoparticles; and the platinum&molybdenum carbide@hollow carbon sphere represents that the surface of the hollow carbon sphere is loaded with molybdenum carbide nanoparticles and platinum nanoparticles at the same time. The anode catalyst is capable of improving the catalytic activity, carbon monoxide poisoning resistance and catalytic stability while reducing the loading amount of the platinum, and is beneficial for promoting the large-scale commercial application of the proton exchange membrane fuel cell.

The invention relates to a low-load Pt/C catalyst hydrogen diffusion anode and a preparation method and application thereof. The preparation method comprises the steps that nano carbon is used as a carrier, alkali is used for etching the carbon carrier, then sodium gluconate is used as a complexing agent, chloroplatinic acid is used as a platinum source, and a dipping-thermal reduction method is used for preparing a catalyst. The catalyst carrier has high micropore capacity and is beneficial to dispersion of platinum catalyst particles, so that the catalyst still has high catalytic activity under low platinum loading capacity, and the cost of the platinum catalyst can be obviously reduced. When the catalyst is used for preparing a hydrogen diffusion anode and the electrode is used for zinc electrodeposition, the hydrogen diffusion anode has the characteristics of low cell voltage and low unit consumption of electric energy, and compared with an existing metal anode zinc electrodeposition method, the unit consumption of the electric energy of zinc can be reduced by 60.1%. Compared with an existing gas diffusion electrode zinc electrodeposition technology, under the condition that the platinum loading capacity of the catalyst is reduced, the cell voltage is reduced by 0.31 V, and the unit consumption of the electric energy is also reduced by 70.64 kW * h/t.

The invention discloses a platinum catalyst and a preparation method and application thereof. The platinum catalyst comprises platinum nanoparticles and a carrier, the platinum nanoparticles are uniformly loaded on the surface of the carrier, and the platinum loading capacity on the platinum catalyst is lower than 1.0 wt.%. The preparation method of the platinum catalyst comprises the following steps: dipping a carrier in a platinum precursor solution, carrying out ultrasonic treatment, removing a solvent, and carrying out reduction treatment in a protective atmosphere to obtain the platinum catalyst. The catalyst is low in precious metal platinum content, good in dispersity, capable of providing higher catalytic activity and better catalytic stability, easy to prepare, low in cost, low in energy consumption, free of pollution, short in time and wide in application prospect.