27 results about "Platinum black" patented technology

The invention discloses a superfine nano platinum black catalyst with a three-dimensional self-supporting structure and a preparation method and application thereof, and relates to the technical field of catalysts.The preparation method comprises the following steps that platinum salt is dissolved in water, and a first solution is obtained; adding a water-soluble inorganic polymerization inhibitor into the first solution, and stirring and mixing at a first temperature to obtain a second solution; adding an alkaline solution into the second solution, and stirring and mixing at a second temperature to obtain a third solution; drying the third solution to obtain precursor powder; placing the precursor powder in a reducing atmosphere, and carrying out heat treatment at a third temperature to obtain a catalyst semi-finished product; soaking, dispersing, washing and drying the obtained catalyst semi-finished product in a small molecular alcohol water solution to obtain the platinum black catalyst, and interweaving platinum nanowires of the platinum black catalyst to form a three-dimensional network with a porous structure and a large specific surface area. The catalyst shows excellent catalytic activity, durability and mass transfer performance.

The invention relates to the technical field of organic silicon catalysis, and discloses a hydrosilylation reaction catalyst and a preparation method thereof, the catalyst is prepared from a platinum complex catalyst solution, maleic anhydride, triphenyl borate, tetraethoxysilane, propylene carbonate and diethylene glycol dibutyl ether; the preparation method comprises the steps of solvent water removal, electronic relay adduct preassembly, active metal introduction, thermal induction aging and the like. An electron-deficient coordination center is constructed through a step-by-step process, the electron cloud density of the platinum center is reduced by utilizing the Lewis acid characteristic of triphenyl borate, and the solvent cage effect of propylene carbonate is matched, so that the high-temperature tolerance of the catalyst is improved, and the generation of platinum black is effectively inhibited; meanwhile, the solubilizing and bridging effects of diethylene glycol dibutyl ether are utilized, the compatibility problem of a high-polarity component and a non-polar silicone oil matrix is solved, and the obtained catalyst has high activity, high regioselectivity and excellent long-term storage stability.

The invention discloses a fuel cell dry membrane electrode and a preparation method thereof, a catalyst and an ionomer are mixed in an aqueous solution, in the directly used catalyst, platinum black particles and a carbon carrier are anchored through a surface functional group, platinum nanoparticles are good in dispersity, and in the aqueous solution, the platinum black particles and the carbon carrier are uniformly dispersed. The negative-SO3H group from the ionomer particles can attract the positively-charged Pt particles, so that the ionomer can uniformly cover the surfaces of the Pt particles, an ionomer / Pt particle interface is spontaneously formed, the ionomer can be uniformly distributed on metal active sites, on one hand, the transfer of protons to the active sites can be accelerated, the reaction kinetics can be improved, and on the other hand, the reaction efficiency can be improved; on the other hand, metal dissolution or poisoning is reduced, and membrane electrode performance and service life are improved. The use of toxic and expensive organic solvents is avoided, a more environment-friendly and lower-cost dry preparation process is adopted, proton membrane swelling in the preparation process is avoided, and the proton conductivity is improved.

The present invention discloses a MEMS thermal temperature difference type flow sensor and a manufacturing method thereof. The flow sensor includes: a substrate provided with a heat insulation cavity; a dielectric layer formed on the upper surfaces of the substrate and the heat insulation cavity; a micro heater and a thermistor formed on the upper surface of the dielectric layer, and the micro heater and the thermistor are partially located above the heat insulation cavity; platinum black covering at least part of the micro heater and the thermistor. The flow sensor disclosed by the present invention has a simple preparation process, strong controllability and high compatibility. By forming platinum black on the micro heater and the thermistor, it is beneficial to increase their surface areas, thereby accelerating the heat exchange efficiency with gas molecules and improving the sensitivity of the device. In addition, the increase in the surface area is also beneficial to improving the thermal utilization rate of the micro heater, thereby playing a role in reducing power consumption.

The application belongs to the technical field of proton exchange membranes, and particularly relates to a preparation method of a multilayer gradient enhanced proton exchange membrane and a product thereof. The method comprises the following steps: cleaning and pretreating a base film; preparing a nitrogen / tungsten-based platinum black catalyst and preparing PFSA resin slurry containing the catalyst; coating the PFSA resin slurry on both sides of the e-PTFE film through a slit to obtain a proton conduction layer; irradiating a PEEK film with ultraviolet light and coating the PEEK film with TiO2 sol to form a mechanical enhancement layer; assembling the functional layers into a "sandwich" structure through PFSA resin adhesion; and performing low-temperature gradient drying and high-temperature annealing, and then performing off-line activation to obtain the multilayer gradient enhanced proton exchange membrane.

To provide an electrode advantageous from the perspective of facilitating the activation of an enzyme or a coenzyme.SOLUTION: An electrode 1a activates an enzyme or a coenzyme by electron transfer with at least one member selected from the group consisting of an enzyme and a coenzyme. The electrode 1a contains platinum black and comprises a layer 14 that forms the surface of the electrode 1a. In the X-ray diffraction (XRD) pattern of surface 1s, a proportion P111 is 60% or more. The proportion P111 is the proportion of the maximum diffraction intensity peak originating from the platinum (111) plane in the total sum of maximum diffraction intensity peaks originating from the platinum (111), platinum (200), platinum (220), and platinum (311) planes.SELECTED DRAWING: Figure 1A

The present application relates to the technical field of water electrolysis for hydrogen production and discloses a hydrogen removal layer, a preparation method therefor, a hydrogen removal proton exchange membrane, a membrane electrode, and a water electrolysis hydrogen production apparatus. The hydrogen removal layer comprises the following components in parts by weight: 10-20 parts of a metal oxide, 10-20 parts of a catalyst, and 2-10 parts of an ionomer. The catalyst comprises at least one of a platinum black catalyst, an iridium black catalyst, and a palladium black catalyst. The hydrogen removal layer described in the present application can effectively reduce the hydrogen content in oxygen on the anode side of a proton exchange membrane.

The present invention provides a composite separator, comprising a separator and a carbon material, that is, an activated carbon felt with hydrogen-oxygen reaction catalytic activity is introduced on one side of the AGM separator close to the negative electrode or the positive electrode. The activated carbon felt with catalytic activity is prepared by a technical route of activating the carbon felt, impregnating it, and depositing platinum black by in-situ reduction method. Through the assembly and characterization of the battery, the results show that by introducing an activated carbon felt with hydrogen-oxygen reaction catalytic activity on one side of the AGM separator, the gas generation amount and water consumption of the lead-carbon battery can be significantly reduced, thereby further prolonging its cycle life and further improving its safety.

The invention discloses a PEM electrolyzed water membrane electrode with a hydrogen elimination function and a preparation method, and belongs to the technical field of hydrogen production by electrolyzed water. The membrane electrode comprises a cathode catalyst layer, a cathode physical barrier layer, a cathode dehydrogenation layer, a proton exchange membrane, an anode physical barrier layer, an anode dehydrogenation layer and an anode catalyst layer. Wherein a Pt / C catalyst is adopted as a cathode catalyst, a cathode physical barrier layer is a mixture of short side chain resin and a fluorine-containing compound, and platinum black and other materials are selected as a cathode dehydrogenation catalyst; the anode physical barrier layer is a short side chain resin layer, the anode dehydrogenation catalyst is porous platinum black and the like, and the anode catalyst is an iridium-based catalyst. The preparation method comprises the following steps: preparing each layer of slurry step by step, sequentially coating two sides of the proton exchange membrane with the slurry, drying, rolling and the like. Through the synergistic effect of multiple hydrogen resistance and hydrogen elimination structures, the hydrogen content of the anode side is effectively reduced, the operation safety of the electrolytic cell is improved, meanwhile, the problems of resistance increase, catalyst loss and the like in the prior art are solved, and good application prospects are achieved.

The invention discloses a method for preparing platinum black nanoparticle powder, and relates to the technical field of purification of platinum group metals in precious metal smelting. The method comprises the following steps: first preparing an organic alcohol solution of a platinum salt, adding a sodium hydroxide aqueous solution and mixing uniformly, and then placing the mixture in an ultrasonic reactor for reaction after uniform dispersion. After the reaction is completed, centrifuging to separate a platinum nanoparticle precipitate, placing the platinum nanoparticles in pure water, and repeatedly ultrasonically washing the platinum nanoparticles to remove organic matter and impurity ions; using a solvent exchange method to disperse the platinum nanoparticles in a hot saturated ammonium carbonate aqueous solution, followed by cooling and solid-liquid separation; and heat-treating the solid-phase product to obtain a platinum nanoparticle product. The method has simple process, low cost, low platinum particle loss rate, and the obtained product has good electrochemical activity, large specific surface area, and low apparent density.

The invention relates to a preparation method of tranexamic acid, which comprises the following steps: by taking p-halobenzonitrile and nitromethane as raw materials, carrying out SNAr reaction in the presence of alkali to obtain p-nitromethylbenzonitrile, carrying out catalytic hydrolysis with sulfuric acid to obtain p-nitromethylbenzoic acid, and carrying out hydrogenation reaction on the p-nitromethylbenzoic acid and hydrogen under the catalysis of platinum black and sulfuric acid to generate 4-aminomethylcyclohexanoic acid. And carrying out conversion reaction under the catalysis of sulfuric acid to obtain a tranexamic acid crude product, and refining to obtain a tranexamic acid finished product. The process is easily available in raw materials, few in synthesis steps and suitable for industrial production.

The application discloses a method for selectively recovering platinum from waste nickel-platinum target material, and belongs to the technical field of precious metal separation. In the method, different physical forms of the waste nickel-platinum target material are treated by using appropriate pretreatment methods. For planing materials, an acidic dissolving agent is used to selectively dissolve nickel; for block or ingot materials, aqua regia is used to completely dissolve and then reduce and enrich platinum. The platinum-containing material obtained through pretreatment is dissolved by using aqua regia, the pH of the solution is adjusted to 0.2-0.9, a reducing agent is added to perform a reduction reaction, platinum is selectively precipitated as platinum black, and then sponge platinum with a purity of greater than or equal to 99.95% is obtained through calcination. The method realizes targeted treatment of different forms of waste materials, and through accurate pH adjustment and the synergistic effect of a specific reducing agent, efficient and selective reduction of platinum is realized, the residual platinum in the filtrate is less than 0.5 ppm, secondary recovery is not needed, the process is short, safety is high, the product purity is high, and the method is suitable for industrial production.

The invention provides a PEM water electrolysis anode diffusion layer and a preparation method thereof, and relates to the technical field of PEM water electrolysis. The anode diffusion layer comprises a porous layer and a microporous layer. The porous layer is a titanium dioxide nanofiber support layer, which is prepared by hot pressing and calcining at least two layers of titanium nanofiber layers. The surface of the titanium dioxide nanofiber support layer is prepared with a microporous layer, and the microporous layer comprises platinum black, spherical dehydrogenated titanium powder and a binder. The titanium nanofibers are placed on a hot press in batches for hot pressing, and the mass of the titanium nanofibers added each time gradually increases. The anode diffusion layer of the invention has strong support and toughness, high porosity and uniform pore distribution, and improves the water-gas transmission capacity during water electrolysis operation. PTFE is added to the porous layer, which improves hydrophobicity and is conducive to the conduction of water and gas. The dehydrogenated titanium powder is added to the microporous layer to improve the conductivity of the diffusion layer. The addition of platinum black promotes the progress of the water electrolysis reaction, so that the electrochemical performance of the membrane electrode is significantly improved.

A method for preparing platinum black by WO3 photocatalysis, comprising the following steps: (1) configuring a chloroplatinic acid solution with a certain concentration, adding a certain amount of ethanol into the solution, and adjusting the pH value of the solution to 1.0 by using 3 M dilute hydrochloric acid; (2) adding WO3 semiconductor nanoparticles with a particle size of 50 nm into the solution in step (1), stirring in the dark state for 30 minutes, and after reacting for a certain time under ultraviolet light, separating and drying by suction filtration to obtain Pt / WO3 particles; (3) dispersing the Pt / WO3 particles obtained in step (2) in a 0.1 M NaOH solution for alkali leaching, stirring at room temperature for 12 h, and after centrifugal washing and vacuum drying, obtaining elemental platinum black nanoparticles.

A wearable electrophysiological microneedle sensor, a manufacturing method, and an early identification method for plant stress. The microneedle sensor comprises a gel substrate and microneedle modules. Each microneedle module comprises a microneedle array, an adhesive layer, a conductive layer, and a silver wire, wherein the microneedle array is sequentially coated with the adhesive layer and the conductive layer, and the conductive layer is electrically connected to the silver wire. Each microneedle array comprises a microneedle base and microneedle bodies arranged on the microneedle base in an array, and platinum black is deposited on the conductive layer of each microneedle body. Electrophysiological signals of plants are collected by the microneedle sensor, the electrophysiological signals within a preset monitoring period are preprocessed, the preprocessed electrophysiological signals are input to a plant stress identification model, and a plant stress identification result is output. The microneedle sensor can stably and with high fidelity monitor changes in electrophysiological signals of plants caused by instantaneous and long-term stress of the plants, and can identify plant stress with high accuracy in combination with a machine learning model.

The present invention relates to an electrode, which is an in vivo insertable electrode, including a substrate, an electrically conductive layer formed on the substrate, a platinum black layer formed on the electrically conductive layer, a self-assembled monolayer (SAM) formed on the platinum black layer, and a lubricant layer formed on the SAM, a method of manufacturing the electrode, and a medical device including the electrode. The in vivo insertable electrode according to the present invention provides excellent electrical properties such as low impedance. Further, it shows that friction with tissue occurring when the electrode is inserted is reduced, and trauma during insertion and an immune rejection response after insertion is suppressed. Further, in the long term, it is possible to detect signals with high sensitivity throughout the entire period by preventing bioadhesion of in vivo cells, such as immune cells, and other proteins.

This invention provides a method for recovering Pt and Ir from waste water electrolysis membrane electrodes, comprising the following steps: Step S1. Dissolving and separating platinum and iridium: The waste water electrolysis membrane electrode is soaked in an organic solvent and separated to obtain a catalyst mixture residue. The catalyst mixture residue is added to a first reagent and calcined at high temperature to obtain precious metal residue. The precious metal residue is dissolved in hydrochloric acid and filtered to obtain a mixed residue. Then, the mixed residue is dissolved in a solvent and filtered to obtain chloroplatinic acid and iridium residue. The chloroplatinic acid is then reduced and purified to obtain platinum compound or platinum black. Step S2. Separating iridium: The iridium residue is added to a second reagent to oxidize and dissolve the iridium residue into chloroiridium acid and insoluble residue. The chloroiridium acid is oxidized with an oxidant, and then ammonium chloride is added and stirred to precipitate it to obtain ammonium chloroiridate. After purification, iridium compound or iridium black is prepared, and the insoluble residue is dissolved in aqua regia for reuse. This invention adds hydroxide to the precious metal residue during calcination, minimizing mechanical entrainment loss and preventing melt splashing during oxidative calcination.

The application discloses a kind of ultrafine nano platinum black catalyst of three-dimensional self-supporting structure and its preparation method and application, it is related to catalyst technical field, including the following steps: platinum salt is dissolved in water, and first solution is obtained;Water-soluble inorganic polymerization inhibitor is added to first solution, and stirring is mixed at first temperature, and second solution is obtained;Basic solution is added to second solution, and stirring is mixed at second temperature, and third solution is obtained;Third solution is carried out drying treatment, and precursor powder is obtained;Precursor powder is placed in reducing atmosphere, and heat treatment is carried out at third temperature, and catalyst semi-finished product is obtained;The catalyst semi-finished product obtained is soaked using small molecule alcohol aqueous solution, disperses, washes, dries, and platinum black catalyst is obtained, and platinum nanowire of platinum black catalyst is interwoven, and three-dimensional network with porous structure and large specific surface area is formed.The catalyst shows excellent catalytic activity, durability and mass transfer performance.

The invention relates to a preparation method of a platinum black catalyst containing a small amount of carbon, and belongs to the technical field of electrochemical catalysts. The method comprises the following steps: dissolving a halogen-containing platinum precursor in a strong acid solution, adding silver ions for reaction, and removing precipitates to obtain a reaction solution; adding a boron-phosphorus co-doped carbon material into the reaction liquid; adjusting the pH of the reaction solution in the presence of a pH buffer agent to convert the platinum species into platinum hydroxide and / or platinum oxide; and then carrying out reduction treatment to obtain the platinum black catalyst containing a small amount of carbon. The functional groups and defect structures on the boron-phosphorus co-doped carbon surface are utilized to guide nucleation and growth of platinum species in the reduction process, and platinum black particles which are small in particle size and uniform in distribution are obtained. The obtained catalyst has relatively low density and remarkably improved dispersity and slurry stability while keeping high platinum loading capacity; compared with pure platinum black, the catalyst provided by the invention shows higher electrochemical activity surface area and enhanced electrochemical reduction activity.

The invention relates to the technical field of catalytic materials, and provides a preparation method of a particle size controllable platinum black catalyst for PEM water electrolysis hydrogen production. The preparation method comprises the following steps: mixing a platinum precursor, bromide, water and alcohol to obtain a precursor mixed solution; mixing the precursor mixed solution with an alkaline solution to obtain an alkaline mixed solution; and then carrying out reduction reaction on the alkaline mixed solution under a microwave condition to obtain the platinum black catalyst. According to the method provided by the invention, the particle size of the platinum black catalyst can be effectively controlled, the obtained platinum black catalyst is uniform in particle size, good in dispersity, high in activity, simple to operate and good in repeatability, and uniform batch preparation can be realized. Results of the embodiment show that the prepared platinum black catalyst is used as a PEM electrolytic cell membrane electrode cathode, a commercial iridium oxide catalyst is used as an anode, and the electrolytic voltage is only 1.78 V at 60 DEG C when the current density is 2A cm <-2 >, and is far lower than that of commercial platinum black and platinum carbon catalysts at present.

The invention belongs to the technical field of precious metal nano material preparation, and particularly relates to a method for preparing a platinum black catalyst with controllable particle size under the assistance of amidine ligands, which comprises the following steps: dispersing platinum salt in a mixed solvent of deionized water and monohydric alcohol to form slurry with the platinum mass concentration of 0.24-2wt%; adding an amidine ligand aqueous solution into the slurry; adjusting the pH value of the solution to 9-10, heating the reaction solution in an oil bath under a stirring condition, raising the temperature to 80-110 DEG C at a speed of 1-5 DEG C / min, carrying out a reduction reaction for 1-6 hours, and carrying out centrifugal separation, washing and drying on the product; the obtained black powder is heated to 100-250 DEG C at the speed of 2-5 DEG C / min in the inert atmosphere, heat treatment is conducted for 30-180 min, and the platinum black catalyst is obtained. The platinum black catalyst with high purity and controllable particle size is prepared by adding amidine substances through a water alcohol-alkaline composite reduction system under mild conditions.

The invention discloses a platinum-doped proton exchange membrane, a preparation method thereof and a fuel cell, and belongs to the technical field of fuel cells. The platinum black with catalytic activity and the perfluorinated sulfonic acid resin are fully mixed, and the platinum-doped proton exchange membrane which is uniform in thickness, high in conductivity and resistant to free radicals is prepared in a spraying mode. When the platinum-doped proton exchange membrane is applied to a fuel cell, the proton exchange membrane is doped with platinum with catalytic activity, so that the platinum-doped proton exchange membrane can react with oxygen in cross transmission, and the oxygen is prevented from penetrating through the platinum-doped proton exchange membrane to react with an anode to generate free radicals with oxidation activity; therefore, the influence of free radicals on the structure of the platinum-doped proton exchange membrane is reduced, and the platinum-doped proton exchange membrane has the advantages of long service life, high stability and strong conductivity.

The invention provides a microelectrode modification method which can be applied to the technical field of neurotransmitter electrochemical detection and neural microelectrode modification. The method comprises the following steps: electroplating a platinum black nanoparticle film on the surface of a detection site; and electroplating a layer of organic composite film containing a conductive polymer and a carbon nanomaterial on the platinum black nanoparticle film to obtain the surface-modified microelectrode. The invention also provides a method for electrochemical detection of serotonin in the brain. According to the present invention, the specific modification parameters are adopted to achieve the double-layer structure modification structure of the electrode electrochemical site so as to enhance the electrochemical detection performance, and the square wave voltammetry detection method is adopted to improve the serotonin detection precision and the serotonin detection sensitivity, such that the method can be used for the real-time detection and the long-term monitoring of the internal body neurotransmitter of the experimental animal brain.

The application relates to the technical field of silicone catalysis, and discloses a hydrosilylation reaction catalyst and a preparation method thereof. The catalyst is made of a platinum complex catalyst solution, maleic anhydride, triphenyl borate, tetraethyl orthosilicate, propylene carbonate and diethylene glycol dibutyl ether; the preparation method involves the steps of solvent dewatering, pre-assembly of an electronic relay adduct, active metal introduction and heat-induced aging. The application constructs an electron-deficient coordination center through a step-by-step process, lowers the electron cloud density of a platinum center by using the Lewis acid property of triphenyl borate, improves the high-temperature resistance of the catalyst by matching the solvent cage effect of propylene carbonate, and effectively inhibits the generation of platinum black; meanwhile, the solubilization bridging effect of diethylene glycol dibutyl ether is used to solve the compatibility problem of high-polarity components and non-polar silicone oil matrix, and the obtained catalyst has high activity, high regioselectivity and excellent long-term storage stability.

An electrochemical microsensor comprising an array of working microelectrodes, the working microelectrodes include:one or more bare microelectrodes;one or more thick film-coated microelectrodes, optionally with conductive additive incorporated into the coating, selected from the group consisting of polysaccharide-coated microelectrodes and platinum black-coated microelectrodes;one or more thin film-coated microelectrodes selected from the group consisting of reduced graphene oxide-coated microelectrode and transition metal chalcogenide-coated microelectrodes;wherein the electrochemical microsensor further comprises a counter electrode and optionally one or more reference microelectrode(s).

The invention discloses a method for synthesizing platinum acetylacetonate and preparing platinum black in series, which comprises the following steps: S1, adding alkali to adjust the pH value of a chloroplatinite solution, filtering and collecting a platinum-containing reaction precipitate, and washing until the platinum-containing reaction precipitate does not contain chlorine; s2, dissolving the platinum-containing precipitate in nitric acid, dropwise adding acetylacetone for reaction, adding alkaline sodium salt or potassium salt to adjust the pH value of the reaction system to generate faint yellow platinum acetylacetonate solid precipitate, and recrystallizing the generated platinum acetylacetonate with benzene to obtain a pure product; s3, after the platinum acetylacetonate is generated, the reaction mother liquor is concentrated to obtain a platinum-containing solid material, and the platinum-containing solid material is heated and calcined; and S4, leaching the calcined material with hot water, boiling with dilute nitric acid, cooling, filtering, washing with deionized water, and carrying out vacuum drying to obtain platinum black. According to the method, the preparation processes of two products, namely the platinum acetylacetonate and the platinum black, are combined and are carried out in series, so that the high-efficiency preparation of the chloride-free platinum acetylacetonate and the platinum black is realized, and the platinum utilization rate is greater than or equal to 98.0%. The average particle size of the prepared platinum black is less than 10nm, and the specific surface area is 11-13m < 2 > / g.

The application provides a preparation method of nano platinum metal particles and belongs to the technical field of nano metal synthesis. In an alkaline environment, in a water-alcohol two-component solvent, sodium citrate is used as a carrier and a platinum salt is used as raw material, the solubility of sodium citrate in the solvent is adjusted, an in-situ template is generated, and the nano platinum metal particles are prepared. The application ingeniously uses the feature that the solubility of sodium citrate is different in different solutions. The sodium citrate is not only used as a reducing agent, but also precipitates as a carrier of the nano platinum particles after the reaction is completed. The carrier is dissolved and washed in water, and solid platinum black is obtained. The application can effectively avoid agglomeration during the drying process of the platinum black and reduce the cost.