113 results about "Formic acid fuel cell" patented technology

The invention relates to a platinum-induced aurum core/ palladium platinum island-shaped alloy shell structure nanorod solution and a preparation method. The structure consists of a cylindrical aurum nanorod inner core and an island-shaped porous palladium platinum alloy shell coated on the outer surface of the inner core. The preparation method comprises the following steps of: firstly preparing aurum crystal seed solution; secondly, preparing aurum nanorod solution and purifying the aurum nanorod solution; thirdly, mixing the purified aurum nanorod solution, chloropalladate solution and potassium tetrachloroplatinate solution and uniformly shaking the mixture, and adding ascorbic acid water solution into the mixture to obtain mixed solution; and placing the mixed solution in constant-temperature water bath for reaction and then adding hexadecyl trimethyl ammonium bromide water solution into the mixed solution and finally performing the centrifugal separation on the mixed solution to obtain platinum-induced aurum core/ palladium platinum island-shaped alloy shell structure nanorod solution. The solution has the advantages of high catalyzing capability, high catalyzing efficiency and high CO poisoning resistance for electrocatalysis oxidation of formic acid, low costs and the like, and is used for directly preparing a formic acid fuel cell catalyst. In addition, the method is simple, low-energy, environmentally-friendly and high-efficiency.

The invention relates to a preparation method of a nanometer Pd or the Pd platinum gold electrocatalysis catalyzer which is used in a kind of fuel cell, whose characteristic lies in that dissolve the mixture of the ration Pd salt or the Pd salt and the platinum salt (in which the Pd atomic ratio accounts for metal quantity 10-100%) in the water, after joining the right amount complexing agent solution, elevates temperature to 0-80deg.C and keeps the temperature 5 minutes to 8 hours, then cooling to the room temperature, adjusts the pH value to 5 to 12 and adds the carbon carrier, then adds the solution of hydroboration sodium, hydrazine or formic acid and so on reducing agent under the 0 to 80deg.C , and maintains 10 minutes to 10 hours, then filtrating, laundering, dry, finally in inert atmosphere or reducing atmosphere through 100 to 300deg.C heat treatment in 0.5 to 10h, namely carries the carbon Pd or the Pd platinum electrocatalysis. The particle size of catalyst is controllable, adjustable, the composition is controllable, regards the heat treatment temperature to be different, the particle size which obtains is relatively 1.8nm to 20nm above, and the granule distribution is narrow, is suitable to serve as the direct formic acid fuel cell anode catalyst as well as the direct methanol fuel cell anti-methyl alcohol negative pole catalyst.

A passive-pumping liquid feed fuel cell system includes a cartridge module, a fuel delivery module, a fuel cell module and an exhaust module. In fuel delivery mode, a bladder in the cartridge module is passively pressurized by permeable gas separated from liquid fuel to a pressure greater than fuel cell pressure, and doses are delivered to the fuel cell by controlling a single fuel valve. In fuel return mode, unused liquid fuel is separated in the exhaust module while the fuel cell is operated in a temporary high load mode, thereby generating anode gas pressure greater than bladder pressure and transferring unused fuel back to the bladder. The returned fuel maintains bladder volume and internal pressure for ongoing fuel dosing. The system provides compact and efficient micro-dose operation of low power formic acid fuel cells, and is operable with highly concentrated stored fuel and resulting high energy capacity.

The invention relates to the field of cathode catalysts of proton-exchange membrane fuel cells (comprising direct alcohol fuel cells, direct formic acid fuel cells and direct dimethyl ether fuel cells and the like), and provides a preparation method of a carbon-loaded Co core-Pt shell nanoparticle catalyst. Carbon-loaded Co@Pt nuclear shell nanoparticles are prepared by connecting sodium chloroplatinate on the surface of a pre-synthesized Co core through hydrogen-bond interaction by way of chemical reduction and heat treatment. The carbon-loaded Co core-Pt shell nanoparticles synthesized by the method are highly dispersed, and the grain size is 3-6.5nm. The mass ratio activity (0.5V vs.SCE) of the carbon-loaded Co core-Pt shell nanoparticles on catalytic oxygen reduction reaction at room temperature can reach 158.5mA.mg<-1>Pt to the maximum extent, and is superior to that of an industrial Pt/C catalyst (JM-3000). The catalyst can be applied to the field of cathode catalysts of proton-exchange membrane fuel cells.

The invention relates to graphene-loaded double-metal nano particles for methanol and ethanol fuel cells, and a preparation method for the graphene-loaded double-metal nano particles. The method comprises the following steps of: sequentially adding graphene oxide, polymeric dispersant, and anionic surfactant into a water-ethanol mixed solution, stirring, adding double-metal nano particles, and adding sodium borohydride to obtain black precipitate double-metal nano particle graphene; and performing centrifugal separation on precipitate by using a centrifugal machine, repeatedly washing by using secondary deionized water and ethanol to remove unreacted reactant, and then performing vacuum drying. According to the method, gold and silver which is low in price, and non-noble metal such as cobalt and nickel which is lower in price is used instead of noble metal such as platinum and ruthenium which is high in price, so cost is reduced. Methanol is catalyzed and ethanol is oxidized under thealkaline condition, so the condition that intermediate carbon monoxide poisons a catalyst under the acid condition so that the activity of the catalyst is reduced can be effectively overcome. The graphene-loaded double-metal nano particles can be directly used for methanol and ethanol fuel cells, formic acid fuel cells, and organic catalytic reaction.

The invention belongs to a preparation method for a direct formic acid fuel cell carbon-supported palladium nanometer catalyst, which takes (WO3) n and xH2O or (MoO3) n and xH2O as colloid source to form metal colloid with PdCl2 and uses NaBH4 for reducing, thus obtaining the carbon-supported palladium catalyst. The palladium particles of the catalyst have uniform distribution and small average grain size. The catalyst prepared by the method has higher performance on the catalytic oxidation of formic acid than the carbon-supported palladium catalyst prepared by the traditional impregnation method which has the same loading capacity but no colloid source. The method with simple practice does not need protective agent and the colloid source can be removed through simple washing; therefore, the method is suitable for batch preparation of the carbon-supported palladium catalyst.

The invention relates to the field of anode electrocatalysts for PEMFC (Proton Exchange Membrane Fuel Cells) (including direct-methanol fuel cells, direct-formic-acid fuel cells and the like), and provides a high-performance Pd/C catalyst material and a preparation method thereof. The palladium-carbon nanocatalyst is characterized in that a modified high-area carbon is formed by two-step liquid-phase reaction methods, Pd particles are uniformly dispersed on the surface of the high-area carbon through liquid-phase complexing coreduction. The mass ratio activity of the catalyst to the formic acid electro-oxidation at room temperature is larger than 1,800mA/mg<-1>Pd, and the palladium-carbon nanocatalyst can be used in the field of anode catalysts for PEMFCs.

The invention relates to an ultra-fine high-disperse Pd/C catalyst of formic acid fuel battery. Wherein, it comprises that Pd metal particles are loaded on the carbon carrier while its mass is 1-80% of carbon carrier and its diameter is 3.0nm; and the preparation comprise that adding complexing agent, stabilizer, PdC12 dilute solution and active carbon carrier into water to be vibrated via ultrasonic wave to obtain component A; adding over reducer and vibrating with ultrasonic wave, and the reduced Pd particles are adhered on the carbon carrier, to obtain component B; washing component B, under vacuum or inertia gas, drying it; the complexing agent is ammonium fluoride, sodium fluoride, or potassium fluoride; the stabilizer is selected from boracic acid or borax; and the reducer is NaBH4, KBH4, hydrazine hydrate, and cavaform. The invention has high electric catalyst activity on aminic acid.

The invention discloses a palladium/nitrogen-doped graphene composite electrode catalyst and a preparation method thereof. The preparation method comprises the following steps: carrying out ultrasonic dispersion on oxidized graphene in water, adding tripolycyanamide, heating and stirring the mixture, freezing and drying the mixed system and carrying out high-temperature heat treatment, so as to obtain nitrogen-doped graphene; carrying out ultrasonic dispersion again on the nitrogen-doped graphene in an ethylene glycol solution, adding a palladium nitrate solution to the ethylene glycol solution and mixing the mixture evenly; reducing palladium nitrate by virtue of a mild reduction method, and depositing palladium nanoparticles in-situ on the surface of the nitrogen-doped graphene; and after reaction is ended, carrying out centrifugal separation to obtain a solid product, and washing and drying the product to obtain the catalyst. By virtue of the mild reduction method, the palladium nanoparticles are deposited in-situ on the surface of the nitrogen-doped graphene; and high temperature or high pressure is not needed, so that the preparation method is simple and controllable, and the repeatability is relatively good. The prepared palladium/nitrogen-doped graphene composite electrode catalyst has excellent electrochemical properties as a direct methanol/formic acid fuel cell cathode material.

The invention relates to a method for preparing a carbon-supported palladium or palladium-platinum electro-catalyst for a direct formic acid fuel cell under the auxiliary protection of inorganic salt. The method comprises the following steps of alternately and ultrasonically stirring a palladium or palladium-platinum precursor solution and a carbon carrier to form suspension, adding the inorganic salt and a reducing agent into the suspension, and adjusting the pH value to be 9 to 10; and performing refluxing for 6 to 10 hours at 90 to 100 DEG C in an oil bath, performing cooling and suction filtration, washing a filter cake, and performing vacuum drying and grinding to obtain the carbon-supported palladium or palladium-platinum electro-catalyst for the fuel cell, wherein the finally prepared carbon-supported palladium or palladium-platinum electro-catalyst for the fuel cell comprises 10 to 40 mass percent of metal active ingredients. The catalyst prepared by the method has a component particle size of 2.5 to 3nm, post-treatment is not required, and the method is easy to operate.

The invention relates to a precious-metal nanometer bipyramid and a preparing method thereof. The method includes the steps that an Au decanedron nano-particle protected with poly diallyldimethylammonium chloride serves as a seed, and Pd grows on the surface of the Au decanedron nano-particle in the [110] direction into the bipyramid. When prepared with the method, the Au and Pd nanometer bipyramid controllable in size and uniform in shape can be prepared. According to the Au and Pd nanometer bipyramid prepared with the method, high reproducibility is achieved, and convenience is brought to mass production; high water solubility is achieved, and a biological application in the future is facilitated; in addition, the Au and Pd nanometer bipyramid prepared with the method has a high-index crystal face, is good in catalysis activity and is potential formic acid fuel cell anode catalysts. The method is simple in preparing technology and low in cost and device requirement, and has the good industrial application prospects.

The invention belongs to the technical field of electrochemical energy and relates to a polyhedral Pt-Pd alloy nano catalyst. The preparation method comprises the following steps: by taking octa-aminosilsesquioxane as a stabilizer and taking methanol as a reducing agent, preparing by virtue of a hydrothermal method to obtain the octahedral Pt-Pd alloy nano catalyst with consistent morphology and good dispersity. The polyhedral Pt-Pd alloy nano catalyst has the advantages that the active surface area is large, the catalytic activity is high, harsh conditions are not needed in the reaction, and the operation is simple and feasible. Moreover, the catalyst has huge application prospects in direct formic acid fuel cell anode catalysts.

The invention relates to a three-dimensional mesh nano porous palladium-ruthenium electrode material for a fuel cell and a preparation method thereof. In the invention, EDTA (Ethylene Diamine Tetraacetic Acid) is used as a complexing agent, HCHO (formaldehyde) is used as a reducing agent, a PdCl2 solution or a PdCl2+RuCl3 solution is reduced into nano catalyst particles by a hydrothermal method in one step, and the catalyst particles are deposited on the surface of a titanium sheet to manufacture a corresponding electrode. The catalyst particles are uniformly spherical, wherein the diameters of the catalyst particles are about 60nm, the catalyst particles are mutually connected and piled to form a porous structure, and the criss-cross three-dimensional mesh structure ensures that the electrode material structure is stable. The specific surface area of the prepared electrode material is large, thus the electrode material has high electrochemical activity on formic acid oxidation. Particularly, due to the addition of Ru, the starting potential of formic acid oxidation is greatly advanced. The electrode material has the advantages of simple preparation method, stable structure and good catalysis activity on the formic acid, thus the electrode material can be directly applied to formic acid fuel cells.

The invention provides a preparation method of a Pd(alpha)Pt fuel cell catalyst for a direct formic acid fuel cell. The preparation method comprises the steps of: (a) dispersing a carrier in deionized water by means of alternative ultrasound and stirring to obtain a mixed solution; (b) adding a Pd precursor and an aqueous solution of a reducing agent into the mixed solution obtained in the step (a), and carrying out loading and reduction of a Pd nanometer particle by means of impregnation reduction to obtain a suspension of the Pd loaded carrier; (c) adding a haloid and a Pt precursor into the suspension obtained in the step (b), and heating the resulting product while stirring for replacement reaction; and (d) washing to remove Cl<-1> in the suspension obtained in the step (c) using deionized water, thereby obtaining the Pd(alpha)Pt fuel cell catalyst after filtering and drying. The preparation method provided by the invention does not use a surfactant and a template, surface controllability of a precious metal nanoparticle is realized, and the operation is simple.

The invention discloses an iridium monatomic catalyst used for a direct formic acid fuel cell, and a preparation method of the catalyst. According to the catalyst, a zinc metal compound and an imidazole type organic ligand are coordinated in an iridium metal compound methanol solution to form a metal organic framework composite material packaged with the iridium metal compound; next, the product is subjected to high-temperature calcining in inert atmosphere; the imidazole type organic ligand forms a non-metallic heteroatom nitrogen-doped porous carbon carrier; and the iridium atoms and the surrounding non-metallic heteroatom nitrogen are in interaction to be loaded on the porous carbon carrier in a mode that a single iridium atom is coordinated with four nitrogen atoms (Ir-N4). Through a simple mixed mode, the composite material of the iridium metal compound and the metal organic framework composite material is prepared; and next, through high-temperature pyrolysis, the iridium monatomic catalyst can be obtained. The method is simple and easy to implement; and the catalyst is applicable to the positive electrode reaction of the direct formic acid fuel cell, and has the characteristics of high atom utilization rate, excellent catalytic performance and high stability.

The invention discloses a preparation method for hollow palladium nanospheres. The preparation method comprises the steps that polyethyleneimine serves as a stabilizer, and ascorbic acid serves as a reducing agent; cuprous oxide nanospheres are synthesized at first; and then, the cuprous oxide nanospheres are used as a mold plate, hydrazine hydrate is used as a reducing agent, and potassium tetrachloropalladate or palladium chloride is reduced into the hollow palladium nanospheres which are regular in shape, uniform in size and good in dispersibility and stability through a hydrothermal reduction method. The preparation method for the hollow palladium nanospheres is simple and economical, and the prepared hollow palladium nanospheres show excellent electro-catalysis activity and stability to a formic acid catalytic reaction, have potential application prospects in the direct formic acid fuel cell field and are suitable for industrial large-scale production.

The invention discloses a multiwalled carbon nanotube-loaded PdSn catalyst based on a deep eutectic solvent and a preparation method and application of the catalyst, and relates to a simple and novel method for preparing an anode electrocatalyst for a direct formic acid fuel cell. According to the method, by taking a deep eutectic solvent as a medium, the catalyst is prepared by using a chemical reduction method. The preparation method of the catalyst is simple in process, and mild and environmentally friendly in operating condition. The dimension of catalyzing nano-particles can be obviously reduced by using a deep eutectic solvent system, so that the metal nanoparticles grow along the surface of a carbon nano tube and are agglomerated to form a special chain-like cluster structure, the electrochemical activity surface area of noble metals is increased, and moreover, the charge transfer interaction among the components in a composite material catalyst is further enhanced. Therefore, the electrocatalytic activity and stability of the catalyst on formic acid oxidation are hugely improved, and the catalyst has the excellent anti-CO poisoning capacity.

The invention relates to a precious metal nanoring and a preparation method thereof. According to the method, an Au nanosheet or a decanedron Au nano particle protected by diallyldimethylammonium chloride serves as a template, M-Ag grows on the surface of the Au nanosheet or the decanedron Au nano particle in a directional mode, and then a round or polygonal Au/M-Ag nanoring is obtained by selectively etching Au. The Au/M-Ag nanoring prepared through the method is smooth in surface, uniform in size, high in purity and capable of being produced on a large scale. The Au/M-Ag nanoring prepared through the method and protected through a protective agent has high water solubility and is beneficial for application in biology in the future. The Au/M-Ag nanoring prepared through the method contains a high-index crystal face, is good in catalytic activity and is a potential formic acid fuel battery anode catalyst. The method is simple in manufacturing technology, short in reaction time, low in cost and low in equipment requirement and has good industrial application prospects.

The invention relates to a high-dispersion supported palladium/tungsten carbide catalyst and a preparation method thereof. The preparation method comprises precursor solution preparation, high temperature calcining, template etching, and dipping reduction loading with palladium. The prepared high-dispersion supported palladium/tungsten carbide can be used as an electrocatalyst and is a direct formic acid fuel cell anode electrocatalyst. The high-dispersion supported palladium/tungsten carbide catalyst has good stability, a narrow particle size dispersion range and a high catalyst utilization rate, prolongs a catalyst service life and reduces a fuel cell production cost. The preparation method solves the problem that the traditional preparation method has poor tungsten carbide dispersion effects and easily causes agglomeration so that specific surface area is reduced and a catalyst utilization rate is reduced.

The invention discloses a mono-dispersed Pd-Pt nano-catalyst and a preparation method therefor. According to the invention, with H2PtCl6.6H2O and PdCl2 as metal precursors, octa(amidocarboxyl silsesquioxane) as a protecting agent, and formaldehyde as a reducing agent, the mono-dispersed Pd-Pt nano-catalyst is prepared by a hydrothermal method. The prepared nano-catalyst has the advantages of good dispersing performance, higher electrochemical active specific surface area, and high electrocatalytic activity. The preparation provided by the invention is simple in required equipment and convenient in operation, and has great utilization value in a commercialization process of direct formic acid fuel cells.