33results about How to "Low platinum loading" patented technology

The invention provides a method for preparing a carbon-supported ultra-low platinum catalytic electrode by means of indirect electrodeposition, which belongs to the fuel cell technique field. The method comprises the steps: transition metal M (such as: Cu, Co, Ni and the like) nano-particles in an aqueous solution are highly dispersed and deposited on a porous carbon electrode (PCE) bonded with perfluoro-sulfonated resin through a four-step electrodeposition method, then the obtained M / PCE electrode is immerged into a platinum salt solution for preparing the carbon-supported ultra-low platinum catalytic electrode through displacement reaction. The invention has the advantages of simple process and low costs. The prepared carbon-supported ultra-low platinum catalytic electrode has the advantages of low platinum loading, high electro-catalytic performance, good dispersion of platinum nano-particles and controllable sizes, and can replace the existing commercial platinum carbon (Pt / C) catalyst.

The present invention discloses an electrospinning and electrostatic spraying method for a membrane electrode CCM. According to the present invention, the catalyst layer having the nanometer film structure is obtained by using the electrospinning and electrostatic spraying method, wherein the catalyst layer structure has a high specific surface area so as to increase the three-phase reaction interface, increase the active area of the catalytic layer, and improve the catalyst utilization rate; the polymer nano-fiber membrane has high porosity, such that the mass transfer is easily performed, and the concentration polarization is effectively reduced; and the nano-scale catalytic particles obtained through electrostatic spraying are uniformly distributed on the nano-fiber structure so as to reduce the platinum loading and improve the catalytic performance.

Nanoparticles which contain noble metals alone or noble metals in combination with base metals. The nanoparticles are embedded in an aqueous solution of a temporary stabilizer based on a polysaccharide.

The invention discloses a catalyst based on varisized platinum-zinc nanoparticles loaded on a zinc-containing monatomic carbon-nitrogen carrier, a preparation method and application thereof. The preparation method of the catalyst comprises the following steps of: preparing platinum nanoparticles with different sizes by using an alcohol reduction method, then encapsulating the prepared platinum nanoparticles in a metal organic framework, modifying the metal organic framework by using a surfactant, and then performing calcining at high temperature. At a certain temperature, the influence of thenanoparticle size on the reaction is explored, and at 600-900DEG C, the influence of the calcination temperature on the monatomic content and on the nanoparticle reaction is explored. The catalyst provided by the invention is low in preparation cost, has excellent electrocatalytic activity, super-strong stability and methanol resistance in an electrochemical oxygen reduction reaction, and obviously improves the electrochemical oxygen reduction activity and stability.

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 provides a method for preparing a carbon-supported ultra-low platinum catalytic electrode by means of indirect electrodeposition, which belongs to the fuel cell technique field. The method comprises the steps: transition metal M (such as: Cu, Co, Ni and the like) nano-particles in an aqueous solution are highly dispersed and deposited on a porous carbon electrode (PCE) bonded with perfluoro-sulfonated resin through a four-step electrodeposition method, then the obtained M / PCE electrode is immerged into a platinum salt solution for preparing the carbon-supported ultra-low platinumcatalytic electrode through displacement reaction. The invention has the advantages of simple process and low costs. The prepared carbon-supported ultra-low platinum catalytic electrode has the advantages of low platinum loading, high electro-catalytic performance, good dispersion of platinum nano-particles and controllable sizes, and can replace the existing commercial platinum carbon (Pt / C) catalyst.

The invention belongs to the technical field of new energy materials and applications, and in particular relates to a method for preparing a platinum-cobalt alloy catalyst. The preparation method of the platinum-cobalt alloy catalyst of the invention comprises the following steps: preparation of a catalyst precursor, high-temperature reduction of the precursor, high-temperature alloying of the catalyst, pickling of the catalyst and water washing of the catalyst. The present invention uses pure water as a solvent, which has safety and environmental protection issues; when the precursor is reduced at high temperature, the reducing agent is the carbon in platinum carbon, and no additional reducing agent is needed, which avoids the use of sodium borohydride or hydrazine hydrate, etc. Safety and environmental protection problems caused by toxic reagents; Gel is used as the precursor of platinum-cobalt alloy to prepare platinum-cobalt alloy oxygen reduction catalyst, which ensures the simultaneous reduction of platinum and cobalt; no sodium salt and chloride ions are added, which reduces the difficulty of product post-processing The present invention uses ammonia water to adjust the pH value of the system, and the post-treatment steps are simple; the transition metal cobalt is added to the platinum-carbon catalyst, which reduces the platinum loading of the catalyst while improving the performance of the catalyst.

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 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.

A catalyst layer including: (i) a platinum-containing electrocatalyst; (ii) an oxygen evolution reaction electrocatalyst; (iii) one or more carbonaceous materials selected from the group consisting of graphite, nanofibres, nanotubes, nanographene platelets and low surface area, heat-treated carbon blacks wherein the one or more carbonaceous materials do not support the platinum-containing electrocatalyst; and (iv) a proton-conducting polymer and its use in an electrochemical device are disclosed.

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.

The invention discloses a Pt-M metal alloy catalyst prepared by electrodeposition in an organic system; the conductive carrier of the catalyst is carbon-based; and the Pt-M metal alloy prepared by co-deposition of Pt-M metal in an organic solvent Alloy nanoparticles are uniformly dispersed on the surface of the carrier in the form of physical loading. During the preparation process, the Pt source precursor and the M source precursor are dissolved in an organic solvent, and the volume molar concentration of the metal precursor in the mixed solution is 1-20 mmol / L. In addition, the oxygen in the solution is excluded under the protection of an inert atmosphere, subsequent deposition is performed at different deposition potentials, and cyclic voltammetry electrochemical cleaning is performed. Through the scheme of the present invention, the further reduction of the platinum loading and the enhancement of the catalytic activity of the prepared Pt-M metal alloy nanoparticle catalyst can be achieved, the comprehensive utilization efficiency of precious metals is greatly improved, and the oxygen reduction activity is improved, reducing the Targets such as comprehensive cost of noble metal catalysts.

The invention relates to a method for carrying out surface alloy modification upon nano-grade porous gold. According to the method, an alloy material is deposited on the surface of nano-grade porous gold with a pulse potential method. The method has the steps that: the nano-grade porous gold is connected on an electrode, and is placed in a solution with different metal ions; pulse potential is applied, wherein the pulse skips between a high potential and a low potential; the high potential is fixed at a value with which the different metal ions are not reduced, and the low potential is fixed at a value with which the metal ions in the solution can be reduced; the two potentials form a pulse cycle; and through multiple times of cycles, the alloy modification upon the nano-grade porous gold is completed. With the method, the nano-grade porous gold is subjected to alloy modification. The prepared nano-grade porous gold based catalyst has low platinum load, high activity, high intoxication resistance, and high corrosion resistance.

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 provides a method for preparing a high-efficiency and low-platinum direct methanol fuel cell catalyst, which belongs to the technical field of fuel cells. The present invention first adopts the method of pulse electrodeposition to deposit a layer of nanoscale Ni-P amorphous alloy on the titanium substrate, which has strong corrosion resistance and has a certain auxiliary catalytic effect on methanol oxidation, as a "core / shell" The "core" of the catalyst; then, through the chemical replacement reaction, a completely replaced platinum monoatomic layer is formed on the surface of the Ni-P amorphous alloy, thereby constructing a "core / shell"-like low-carbon catalyst with a synergistic catalytic effect on methanol oxidation. Platinum fuel cell catalyst. The method of the invention is simple and easy, and the production cost is low. The catalyst prepared by the invention can effectively reduce the amount of precious metals and improve the utilization rate of the catalyst, and can replace the existing commercial platinum carbon (Pt / C) catalyst, and is widely used in electric vehicles, various spacecraft, portable electronic equipment, Such as video cameras, notebook computers, electric toys, etc.

The invention relates to a preparation of a platinum catalyst of a direct methanol fuel cell, which adopts a method of electrodepositing and carries out pulse electrodepositing on platinum by two steps, namely a larger current is adopted for forming a crystal nucleus in step I; a small current is adopted for the growing the crystal nucleus in step II; the grain diameter of the prepared catalyst can be reduced through changing the applied electric signal; thereby leading the formed platinum grains to be more dispersive and have a higher covering rate and a larger specific surface; thereby reducing the platinum loading capacity of unit area of the electrodes, improving utilization rate and activity and simultaneously reducing the cost of the catalyst. The method is simple and controllable to be applied. The prepared platinum catalyst can not only be applied to the direct methanol fuel cell, but also can be applied to other fuel cells as catalysts. Besides, the method can be expanded andapplied to platinum-ruthenium codeposition and other multi-metal codeposition.