39 results about "Direct borohydride fuel cell" patented technology

The invention relates to an anode electrocatalyst for a direct borohydride fuel cell and a method for preparing the same, in particular to a method for preparing a porous carbon loading nanometer gold catalyst. The preparation method comprises that: by adopting the metal sol loading method, the surface of the porous carbon carrier after purification and surface oxidizing treatment is loaded with a nanometer gold particle, and the size of the gold particle can be controlled by controlling the adding amount of a reducing agent and the gold concentration in the metal sol. The loading capacity of the gold is 5 to 30 percent, and the particle size of the gold is 2 to 6nm. The porous carbon is one of or a mixture of more than one of carbon nanometer pipe, carbon nanometer fiber, active carbon fiber, graphitized carbon black, active carbon and intermediate phase carbon microsphere, and the specific surface area of the carrier is between 100 and 2,000m / g. The method has the advantages of simple preparation process, unnecessary high-temperature calcination, and easy mass production. The prepared gold particle has the advantages of high-degree dispersion on the surface of the carbon carrier and even size distribution. When used as the anode electrocatalyst of the direct borohydride fuel cell, the anode electrocatalyst has good BH4 electric oxidation catalysis activity.

The invention provides application of a Ni-based catalyst in an anode of a direct borohydride fuel cell. Active components of the catalyst consist of Ni and one or more metal elements in I B and VIIIB groups; the atomic ratio of the Ni to other metal active components in the catalyst is 99:1-8:1; and the active components in the catalyst account for 5 to 80 percent and the balance is a C carrier.A small amount of one or more metal elements in the I B and VIII B groups are added into the Ni-based catalyst to obviously improve the stability and activity of the catalyst; and when the catalyst is used as a catalyst for the anode of the direct borohydride fuel cell, the direct borohydride fuel cell shows excellent performance.

The invention provides a preparing method of a film electrode material using graphite coated paper to load NiAu. Clay is used as a curing agent, the clay and graphite are mixed evenly, then the surface of ordinary paper is coated with the evenly-mixed clay and graphite; 5-5.5g of NH4Cl and 1-1.5g of NiCl2 are dissolved in 50mL of water for preparing an electro-deposition solution; the paper coated with the graphite is maintained in the electro-deposition solution under 1.0V voltage for 20-30min for activation of the coated graphite, then a paper-graphite-Ni film electrode is obtained by 160-180min of electro-deposition of Ni under-1.0 V voltage; the paper-graphite-Ni film electrode is stood in a 1mmol L<-1> HAuClO4 solution for 2 to 4 minutes to obtain a paper-graphite-NiAu film electrode. According to the method, the graphite coated paper the is used, Ni is electrically deposited on the surface of the conductive graphite coated paper, then part of Ni is replaced with Au to prepare a NiAu-loading pencil coated paper catalyst, and the catalytic performance of the positive pole of a direct hydronoron fuel cell can be improved. The problem of poor activity the positive pole of a sodium borohydride fuel cell can be solved.

The invention provides a hydrogen storage alloy anode catalyst of direct hydroboron fuel batteries; transition metal oxide is added in the hydrogen storage alloy anode catalyst, and the mass ratio of the adding quantity of the transition metal oxide and the hydrogen storage alloy is 5-10 : 95-5. The doping of the transition metal oxide provides a new activity position for hydrogen adsorption and dissociation, improves the catalytic activity of the hydrogen storage alloy and solves the problem that anode discharging current of the hydroboron fuel battery is low. The hydrogen storage alloy anode catalyst is characterized in that: the mixture of the transition metal oxide and the hydrogen storage alloy increases the electrical catalysis performance of the hydrogen storage alloy to the hydroboron. In the essence of the invention, on the basis of anode catalyst of the hydrogen storage alloy of the direct hydroboron fuel batteries, the electrochemical oxidation susceptibility of the hydrogen storage alloy to the hydroboron is increased by mixing the transition metal oxide, and the discharge performance of the hydroboron anode is improved.

The invention discloses a direct hydroborate fuel cell adopting a polymer fibrous membrane. A single cell consists of an anode, the polymer fibrous membrane and a cathode, wherein the anode comprises a waterproof air-permeable layer, a current collection layer and a catalytic layer; the cathode comprises a current collection layer and a catalytic layer; and the polymer fibrous membrane is made from main raw materials such as polyamide fibers, polypropylene fibers, polyvinyl alcohol fibers and the like. The fibrous membrane replaces a naffion membrane in the conventional fuel cell, allows ions to freely pass through, and can effectively decrease the internal resistance of the cell, thereby greatly improving the performance of the cell. The anode and cathode of the cell both adopt non-noble metal catalytic materials, wherein the catalytic material of the anode has the function of reducing oxygen rather than catalyzing the decomposition of hydroborate ions, so that the problem of ion 'crossover' in the conventional fuel cell is solved and a fuel solution is allowed to leak to the anode without influencing the catalysis efficiency of the catalytic material of the anode.

The invention provides a preparation method of a carbon surface modified hydrogen storage alloy and a method for improving the anode catalytic performance of a direct borohydride fuel cell. The preparation method includes: mixing hydrogen storage alloy powder and carbon evenly, then placing the mixture into a ball milling tank, conducting ball milling for 1-2h at a speed of 3000-5000rpm under the protection of nitrogen, then taking the mixture out, gradually adding a 60wt.% polytetrafluoroethylene solution and a 1.5wt.% sodium carboxymethylcellulose colloid that are in a mass ratio of 1:1, keeping the mass ratio of the hydrogen storage alloy powder and the carbon quality to the polytetrafluoroethylene solution and the sodium carboxymethyl cellulose at 9-10:1, and stirring them uniformly to prepare a slurry containing the hydrogen storage alloy and carbon, coating foamed nickel with the slurry, and carrying out drying for 2.5h at 70DEG C, thus obtaining the carbon surface modified hydrogen storage alloy, which can be used for improving the anode catalytic performance of a direct borohydride fuel cell.

Disclosed are a core-shell structural anode catalyst for direct borohydride fuel cells and a preparation method thereof. The catalyst comprises Mcore-Aushell nano composite particles which utilize M as the core and utilizes Au as the shell, and the particle size of the Mcore-Aushell particles ranges from 10nm to 50nm. The preparation method includes steps: firstly, adding M-salt and a stabilizing agent into a solvent sequentially, introducing nitrogen gas into the solvent and then stirring and heating the solvent, introducing and stirring nitrogen gas again, dropping a reducing agent to realize reaction and obtain M-nano catalyst sol, and then obtaining M-nano particles after filtering and washing; secondly, dissolving the M-nano particles into solvent, adding stabilizing agent and introducing nitrogen gas into the solvent along with stirring, adding chloroauric acid-tetrahydrofuran solution, introducing nitrogen gas again, dropping reducing agent to realize reaction and prepare nano-catalyst sol, separating and washing the nano-catalyst sol, drying the nano-catalyst sol in vacuum, and finally preparing powdered Mcore-Aushell nano-particle catalyst by means of grinding. The core-shell structural anode catalyst for direct borohydride fuel cells has higher BH4 (tetrahydrobiopterin)-oxidation activity and is low in hydrogen evolution, and accordingly fuel utilization rate is improved.

The invention provides a preparation method of a carbon surface modified hydrogen storage alloy and a method for improving the anode catalytic performance of a direct borohydride fuel cell. The preparation method includes: mixing hydrogen storage alloy powder and carbon evenly, then placing the mixture into a ball milling tank, conducting ball milling for 1-2h at a speed of 3000-5000rpm under the protection of nitrogen, then taking the mixture out, gradually adding a 60wt.% polytetrafluoroethylene solution and a 1.5wt.% sodium carboxymethylcellulose colloid that are in a mass ratio of 1:1, keeping the mass ratio of the hydrogen storage alloy powder and the carbon quality to the polytetrafluoroethylene solution and the sodium carboxymethyl cellulose at 9-10:1, and stirring them uniformly to prepare a slurry containing the hydrogen storage alloy and carbon, coating foamed nickel with the slurry, and carrying out drying for 2.5h at 70DEG C, thus obtaining the carbon surface modified hydrogen storage alloy, which can be used for improving the anode catalytic performance of a direct borohydride fuel cell.

The invention discloses an anode catalyst for a direct borohydride fuel cell, an anode material, a preparation method of the anode material and the fuel cell. The anode catalyst for the direct borohydride fuel cell adopts Co3O4 / SnO2. Co3O4 / SnO2 is attached to the surface of lamellar SnO2 through granular Co3O4, and the lamellar SnO2 is interwoven to form a 3D structure. According to the invention,the granular Co3O4 is attached to the surface of lamellar SnO2 and the lamellar SnO2 is interwoven, so a good supporting effect is achieved for the Co3O4 and the 3D structure similar to a pistil structure is formed; and through the Co3O4 / SnO2 structure, electron transmission is facilitated and more reaction space is provided for the electrolyte, thereby facilitating improvement of catalytic performance.

The invention discloses an anode catalytic material for a direct borohydride fuel cell, an anode material as well as a preparation method thereof and a fuel cell. The anode catalytic material for thedirect borohydride fuel cell directly synthesizes a two-metal catalytic material CoSnx with no carrier and no binder on foam nickel by virtue of a chemical reduction method, and x is 0 to 1. Accordingto the anode catalytic material for the direct borohydride fuel cell, the composite material of Sn and Co is firstly used as the catalytic material for the direct borohydride fuel cell, the anode material with good catalytic activity is combined with a material with high hydrogen overpotential, the obtained CoSnx is high in catalytic performance, the hydrolytic reaction of the borohydride is inhibited, the absolute hydrogen evolution rate is reduced, so that the discharging efficiency of fuel is greatly improved, and the contradiction between the catalytic capacity and the discharging efficiency can be effectively solved. The anode catalytic material for the direct borohydride fuel cell can provide theoretical foundation for optimizing and perfecting the DBFC anode catalytic material.

The invention relates to a leptomonasform direct borohydride fuel cell stack, which comprises an electrode, a bipolar plate, fuel cavities, end plates and a fastening device, wherein the fuel cavities are arranged between the cathodes and the anodes of monocells, any proton exchange membranes are not adopted. The cell stack is formed through connecting the monocells in series by the bipolar plate. Fuel and oxygen (air) respectively enter through a fuel hole and a gas hole on one of the end plates, fuel enters the fuel cavity of each monocell, oxygen (air) enters each monocell in turn along a gas flow field on the bipolar plate after entering, and fuel solution and gas after reacting respectively flow out from the fuel hole and the gas hole on the other end plate. The continuous supplies of fuel and oxygen (air) are achieved through other accessory equipment (such as a peristaltic pump, a peristaltic pump and the like). Since the leptomonasform direct borohydride fuel cell stack directly adopts cathode catalyst with high selectivity to achieve a leptomonasform fuel cell structure, the production cost is lowered in a greater degree, and meanwhile, the speed of electrochemical reaction is further improved, thereby improving the property of a cell.

A composite membrane electrode of a direct borohydride fuel cell relates to a fuel cell membrane electrode. The composite membrane electrode solves the problems that the hydrogen produced by hydrolysis of the direct borohydride fuel cell can not be directly used and the overall utilization rate of the cell fuel is low. The composite membrane electrode of the direct borohydride fuel cell is composed of an anode, a cathode (6) and an electrolyte membrane (3). The anode and the cathode (6) are respectively arranged on two sides of the electrolyte membrane and parallel to the electrolyte membrane;the anode, the cathode and the electrolyte membrane are hot pressed to a membrane electrode; the anode is composed of a borohydride-radical catalytic oxide anode (5) which is arranged on the lower part of the anode and a hydrogen catalytic oxide anode (4) which is arranged on an upper part of the anode. The side reaction of the borohydride radical is unavoidable on the borohydride-radical catalytic oxide anode, and the hydrogen is produced and can continue to react as the fuel on the hydrogen catalytic oxide anode, which can improve the overall utilization rate of the fuel and causing the structure of the whole membrane electrode system to be more compact and safer.

The present invention provides a single-cell activation method for a direct borohydride fuel cell (DBFC). The single-cell activation method is characterized by comprising three steps such as initial stage activation, electrochemical alternating current accelerated activation and cell performance testing, has characteristics of rapid electrochemical reaction interface expansion, short activation time, fuel saving, simple system and the like, and is especially suitable for activation of the DBFC with characteristics of low catalyst activity and long activation time.

A nickel-based catalyst for improving the performance of a direct borohydride fuel cell is characterized in that the catalyst is prepared according to the following simple method of: (1) preparing a NiSO4 solution of 0.2 mol / dm<3> at a normal pressure and a temperature ranging from 293.15K to 313.15K; (2) assembling a three-electrode system, namely placing a smooth Ni sheet (serving as a working electrode) of 2 square meters in the above solution, wherein the Ni sheet is taken as a counter electrode, and a silver / silver chloride electrode is taken as a reference electrode; and (3) depositing Ni on a metal nickel sheet to prepare the nickel-based catalyst by using a constant potential (-0.8V) method. The surface morphology of the catalyst is changed due to deposition of the Ni, the specific surface area is obviously increased, catalytic active sites are greatly increased, and thus, the direct oxidizability of BH4<-> is enhanced; and meanwhile, the charge transfer resistance of electrode reaction is further reduced due to the deposition of the Ni, and fuel discharging efficiency is obviously improved.

A Ni-Cu binary catalyst for improving the performance of a direct boron-hydrogen fuel cell, characterized in that the catalyst is prepared by the following method: (1) under normal pressure, the temperature is in the range of 293.15-313.15K, and the acidic condition is configured at 0.25 mol / L CuSO4 solution; (2) Device three-electrode system: place a 2cm2 Ni sheet as a working electrode in the above solution, use a Cu rod as a counter electrode, and a silver / silver chloride electrode as a reference electrode; (3) On the electrochemical workstation, Ni-Cu binary catalyst was prepared by electrodeposition at -0.1V for 5s by constant potential method. The catalyst enhances the direct oxidation performance of BH4-, weakens the corrosion of the electrolyte on the Ni anode, reduces the charge transfer resistance, and improves the discharge efficiency.