559 results about "Cathode catalyst" patented technology

The invention discloses a preparation method and application of a carbon-loaded cobalt nanoparticle and iron monatomic electro-catalytic material, relates to a preparation and regulation method of a zinc air battery cathode catalyst, and solves the problems of low electricity generation performance and poor stability of an existing rechargeable zinc air battery cathode. Specifically, a high-efficiency and stable-catalysis carbon-loaded cobalt nanoparticle and iron monatomic electro-catalysis material is reasonably designed and successfully synthesized by utilizing the adsorption effect of a metal organic framework (MOFs) and polyvinylpyrrolidone as an ion adsorption layer, and under the condition that active sites are not sacrificed, the high-efficiency and stable-catalysis carbon-loaded cobalt nanoparticle and iron monatomic electro-catalysis material can be used for preparing a high-efficiency and stable-catalysis carbon-loaded cobalt nanoparticle / iron monatomic electro-catalysis material. And the dispersity of cobalt nanoparticles and the catalytic activity of iron monatomic are improved. The obtained material is used as a zinc air battery cathode material, the overall performance of a rechargeable zinc air battery can be improved, and efficient and oriented conversion of the zinc air battery is achieved.

The invention relates to an anion exchange membrane based on isopropyl piperidone and biphenyl and a preparation method of a membrane electrode, the preparation method comprises the following steps: respectively dissolving an aromatic monomer and IPD in a first solvent, and mixing to obtain a mixed solution, the aromatic monomer being BP or TP; dropwise adding an acidic initiator into the mixed solution for reaction at the reaction temperature of-5 DEG C to 0 DEG C to obtain a nitrogen heterocyclic ring polymer intermediate; adding a quaternization reagent into the nitrogen-containing heterocyclic ring polymer intermediate to realize quaternization modification of nitrogen atoms to obtain a quaternization ionomer; and forming a film to obtain the AEM film. The preparation method of the membrane electrode comprises the following steps: respectively forming a cathode catalyst layer and an anode catalyst layer on two opposite sides of an AEM membrane through ultrasonic spraying to obtain the MEA. The AEM membrane and the MEA obtained according to the invention have the characteristics of excellent stability and high water electrolysis performance, can significantly improve the efficiency and durability of AEMWE, and are suitable for the fields of hydrogen production by water electrolysis and the like.

The invention relates to the technical field of proton exchange membrane fuel cell cathode catalysts, and discloses a nanoscale high-entropy intermetallic compound catalyst and a preparation method and application thereof. According to the nanoscale high-entropy intermetallic compound catalyst, a nitrogen-doped porous carbon material derived from zeolite imidazole skeleton-8 is taken as a carrier, and the metal elements of a high-entropy intermetallic compound comprise platinum, copper, cobalt, nickel and iron or platinum, ruthenium, copper, cobalt, nickel and iron. The preparation method of the catalyst comprises the following steps: step 1, preparing a zeolite imidazole framework 8; 2, preparing and purifying a nitrogen-doped porous carbon material carrier; step 3, loading a metal precursor; and 4, preparing the nano-scale high-entropy intermetallic compound catalyst. Nanoscale, high dispersity and structure ordering of the high-entropy intermetallic compound are achieved, the high-entropy intermetallic compound serves as a PEMFC cathode catalyst, the ORR quality activity and durability can be remarkably improved, and Pt loading capacity and cost are effectively reduced.

The invention provides a membrane electrode, a preparation method thereof and a monocell, the membrane electrode comprises a double-cathode catalyst layer, a proton exchange membrane and a gas diffusion layer, the double-cathode catalyst layer comprises a first catalyst layer and a second catalyst layer; the first catalyst layer is connected with the proton exchange membrane, and the second catalyst layer is connected with the gas diffusion layer; the raw materials of the double-cathode catalyst layer comprise a platinum-containing catalyst and an ionomer; the particle size D50 of platinum in the first catalyst layer is smaller than the particle size D50 of platinum in the second catalyst layer. The double-cathode catalyst layer is arranged, and the particle size D50 of platinum in the first catalyst layer is smaller than the particle size D50 of platinum in the second catalyst layer, so that the utilization rate of the material is improved to the maximum extent, the cost is reduced, the performance and the overall durability of the membrane electrode are improved, and the membrane electrode has good development potential.

The present invention provides a catalyst-layer-equipped electrolyte membrane and an application of the same, said catalyst-layer-equipped electrolyte membrane comprising: an anode catalyst layer containing an ionomer and an anode catalyst component that is composed of iridium-containing manganese dioxide, the molar ratio of iridium to manganese in the anode catalyst component being 0.011-0.182, and the logarithm log(amount of ionomer / amount of anode catalyst component) of the ratio of the amount of the ionomer to the amount of the anode catalyst component being −1.40 to −0.46; a proton exchange membrane; and a cathode catalyst layer.

The invention relates to a membrane electrode with high oxygen permeability and a preparation method thereof, the membrane electrode comprises a proton exchange membrane, an anode catalyst layer and a cathode catalyst layer, the anode catalyst layer and the cathode catalyst layer are arranged on two sides of the proton exchange membrane, and anode catalyst slurry comprises an anode catalyst, an ionomer and a dispersing solvent in a mass ratio of 1: (1-10): (10-1000); the cathode catalyst slurry comprises a cathode catalyst, an ionomer, an ionic liquid and a dispersing solvent in a mass ratio of 1: (1-10): (1-10): (10-1000). Compared with the prior art, in order to solve the problem that oxygen mass transfer of a porous carbon carrier in a fuel cell catalyst layer is difficult, the method that ionic liquid and ionomer are mixed in advance, then slurry is prepared, and the slurry is sprayed to prepare the membrane electrode is adopted, so that a compact structure formed by an ionomer membrane on the surface of a catalyst is weakened, and the distribution uniformity of the ionomer membrane is improved; the local oxygen mass transfer resistance is obviously reduced, and the performance of the fuel cell under high current density is improved.

The invention provides a self-humidifying CO2 membrane electrode structure and a preparation method thereof. The self-humidifying CO2 membrane electrode structure comprises an electrolyte isolation plate, the electrolyte isolation plate is provided with an anode side and a cathode side, the anode side is sequentially provided with a cation exchange membrane, an anode catalyst layer, a current collector and an anode electrode plate, and the cathode side is sequentially provided with an anion exchange membrane, a cathode catalyst layer and a cathode electrode plate; the anode electrode plate is provided with a first inlet, hydrogen enters the anode electrode plate from the first inlet and is subjected to a hydrogen oxidation reaction under the action of an anode catalyst to generate protons and electrons, and the protons are migrated to the electrolyte isolation plate through the cation exchange membrane; the cathode electrode plate is provided with a second inlet, CO2 gas enters the cathode electrode plate from the second inlet and is subjected to a reduction reaction under the action of a cathode catalyst to generate a reduction product and OH <->, and OH <-> is migrated to the electrolyte isolation plate through the anion exchange membrane to react with protons. The long-term operation stability of the membrane electrode structure is remarkably improved.

The present invention belongs to the field of electrochemistry, and specifically relates to an anion membrane electrode and a preparation method thereof, and a device for preparing synthesis gas by gas-phase electrolysis of carbon dioxide. The preparation method is as follows: a porous membrane protective layer is covered on the surface of a vacuum heating plate, and then an anion membrane is covered; then an anion exchange ionomer solution and a cathode catalyst anion exchange ionomer solution are sprayed on the surface in sequence. The present invention can reduce the structural damage to the anion membrane caused by the temperature fluctuation of the metal plate surface during the heating process of the vacuum heating plate by introducing a porous membrane protective layer between the anion membrane and the vacuum heating plate; the anion exchange ionomer layer is introduced between the catalyst layer and the anion membrane to increase the bonding strength between the catalyst layer and the anion membrane and increase the stability of the membrane electrode; during the volatilization process of the heating solvent, the solvent can be promoted to volatilize at low temperature by blowing dry, thereby accelerating the membrane electrode preparation process and improving the stability of the membrane electrode, thereby extending the service life of the device.

The invention discloses a fuel cell cathode catalyst and a preparation method thereof, and belongs to the technical field of fuel cells. The preparation method of the fuel cell cathode catalyst comprises the following steps: adding a modified multi-walled carbon nanotube into a chloroplatinic acid aqueous solution with the mass concentration of 5g / L, carrying out ultrasonic treatment at 30-50 DEG C for 1-2 hours, and then carrying out freeze drying; and putting the dry powder into a horizontal tube furnace, introducing inert gas as protective gas, heating to 450-500 DEG C, preserving heat for 1 hour, cooling to room temperature along with the furnace, and taking out to obtain the fuel cell cathode catalyst. The modified multi-walled carbon nanotube is MWCNT / PEI / 5-formyl-2-thiopheneboronic acid, and the 5-formyl-2-thiopheneboronic acid is grafted after the PEI is grafted on the surface of the MWCNT, so that the dispersity of the MWCNT can be obviously improved, the agglomeration phenomenon of the MWCNT is reduced, the dispersion is more uniform, the loading capacity of platinum is high, the electrocatalytic activity of the catalyst is obviously enhanced, and the dosage of platinum is reduced.

The invention relates to the technical field of new energy materials, and discloses a gradient porous three-dimensional interpenetrating network direct ammonia fuel cell membrane electrode. The gradient porous three-dimensional interpenetrating network direct ammonia fuel cell membrane electrode comprises an exchange membrane, an anode catalyst layer, a cathode catalyst layer and a gas diffusion layer, wherein the anode catalyst layer and the cathode catalyst layer have gradient pore size distribution from the exchange membrane side to the gas diffusion layer side; wherein the interiors of the anode catalyst layer and the cathode catalyst layer are provided with three-dimensional interpenetrating network structures. According to the invention, the utilization rate of the catalyst is improved by 30-50%, the mass transfer resistance is reduced by 40-60%, the interface contact is improved, the controllability of the preparation process is improved, the structural stability is enhanced, the power density of the direct ammonia fuel cell reaches 250-300mW / cm < 2 >, the performance retention rate after 5000 cycles can reach 85% or more, and the method has remarkable technical advantages and application prospects.

The invention provides a CoCe-SNC catalyst and a preparation method and application thereof, and belongs to the technical field of hydrogen fuel cell / metal air cell cathode catalysts. The preparation method comprises the following steps: mixing and grinding a metal organic framework ZIF-8 and KSCN, carrying out first pyrolysis, compounding the obtained nitrogen and sulfur-containing co-doped carbon with two metal complexes Co-PM and Ce-PM, and carrying out second pyrolysis to obtain the CoCe-SNC diatomic catalyst. According to the invention, the two-dimensional lamellar structure carbon material and the asymmetric coordination diatomic metal are compounded, so that the catalytic performance of the whole catalyst is improved, and meanwhile, the yield of hydrogen peroxide generated by side reaction is reduced. The catalyst is applied to a hydrogen fuel cell / metal air cell, and the defects that in the prior art, a noble metal catalyst is high in cost, and a non-noble metal catalyst is low in catalytic activity, high in hydrogen peroxide yield, poor in catalyst stability and the like are overcome.

The invention discloses a membrane electrode, a preparation method thereof and a fuel cell, the membrane electrode comprises a catalyst layer and a proton exchange membrane, the catalyst layer comprises an anode catalyst layer and a cathode catalyst layer, and the anode catalyst layer and the cathode catalyst layer are respectively arranged on two sides of the proton exchange membrane; the catalyst layer and the proton exchange membrane are both doped with phosphoric acid. By macroscopically regulating and controlling the PA content of the catalyst layer and the proton exchange membrane in the membrane electrode, more three-phase reaction interfaces are constructed, so that the Pt catalyst can be fully utilized, and unnecessary migration of PA is reduced, thereby avoiding the phenomenon of acid flooding, ensuring sufficient PA in the proton exchange membrane to provide sufficient proton conductivity, and improving the proton exchange efficiency. And the power density of the fuel cell is further improved.

The application discloses a platinum-based high-entropy intermetallic compound and a preparation method and application thereof as a hydrogen fuel cell cathode catalyst, and belongs to the field of fuel cells.The preparation method comprises the following steps: S01, adding platinum salt, at least five other metal salts and a nitrogen-rich organic compound into an organic solvent, uniformly mixing, and obtaining a metal precursor mixed solution; S02, adding a carbon carrier into the metal precursor mixed solution, fully mixing, drying, collecting, and obtaining a precursor; and S03, heat treating the dried precursor under a reducing atmosphere, and performing heat preservation treatment, so as to obtain the platinum-based high-entropy intermetallic compound.The preparation method is simple, low in cost and good in repeatability, the prepared catalyst has the advantages of uniform particle size and high oxygen reduction activity, and has a good development prospect in the field of hydrogen fuel cell catalyst applications.

The invention relates to an AEM electrolytic bath. The current density and the heat exchange capacity of the electrolytic bath are improved. Liquid on the anode side of each single section of the electrolytic cell can uniformly and quickly flow on the surface of the anion exchange membrane, oxygen generated on the anode side can be quickly and effectively discharged out of the electrolytic cell, and hydrogen generated on the cathode side and water permeated from the anion exchange membrane can be timely and efficiently discharged out of the electrolytic cell; certain pressure is provided for the cathode catalyst layer and the anode catalyst layer, so that the catalyst layers are uniformly stressed and attached to the two sides of the anion exchange membrane. In a comparison test of electrolysis with an active area of 300cm < 2 >, under the same conditions of 2V voltage and temperature of 60 DEG C, the current value of the electrolytic bath of a cutting machining flow field on a metal pole plate is 218A, the current value of the electrolytic bath of a spongy foam metal flow field with a groove-shaped flow channel is 289A, and the efficiency is improved by 32.56%. And under other working conditions, the test current is also improved by 20%-32%.

The invention discloses a small-particle-size platinum-based intermetallic compound fuel cell cathode catalyst and a preparation method thereof, rich FeNx sites are generated through nitrogen-rich porous carbon to anchor Pt-based nanoparticles in situ, so that the interaction between a carrier and an alloy is enhanced, the growth of the particles is effectively inhibited, and the formed Pt-based ordered alloy is only 2.3 nm. According to the prepared catalyst, the stable ordered structure is reserved, meanwhile, the Pt atom utilization rate is effectively increased, and preparation of the efficient low-Pt catalyst is achieved. The preparation method is simple, low in cost and good in reproducibility, and the platinum-based alloy catalyst prepared on the basis of the method shows excellent catalytic activity in a battery.

The invention relates to a membrane electrode and application thereof in deuterium-enriched water, and belongs to the field of clean energy development and utilization. The membrane electrode comprises a proton exchange membrane, an anode catalyst and a cathode catalyst, the anode catalyst is an iridium / iridium oxide catalyst with a three-dimensional porous network structure, and the cathode catalyst is a platinum-ruthenium alloy catalyst. The preparation method comprises the following steps: coating one side of the N117 proton exchange membrane with the anode catalyst, coating the other side of the N117 proton exchange membrane with the cathode catalyst, and then performing hot pressing to prepare the membrane electrode. The method comprises the following steps: assembling a membrane electrode into an electrolytic cell, and electrolyzing water by using the electrolytic cell to realize deuterium enrichment. The membrane electrode and the electrolytic cell are reasonable in design, the preparation process is simple and controllable, and the obtained product is high in efficiency and long in service life when used for enriching deuterium and facilitates industrial application.

The invention relates to a membrane electrode of a gradient catalyst layer on a cathode side and a preparation method of the membrane electrode. The method comprises the following steps: providing a proton exchange membrane and an anode catalyst layer; providing first catalyst layer slurry, and coating the surface of the proton exchange membrane with the catalyst layer slurry to obtain a first catalyst layer; second catalyst layer slurry is provided, the second catalyst layer slurry is spun onto the first catalyst layer through an electrostatic spinning technology, a second catalyst layer is obtained after drying, and the first catalyst layer and the second catalyst layer form a double-layer gradient cathode catalyst layer; and carrying out hot-pressing transfer printing on the double-layer gradient cathode catalyst layer and the anode catalyst layer so as to combine the double-layer gradient cathode catalyst layer and the anode catalyst layer on the proton exchange membrane to obtain the membrane electrode. The catalyst layer obtained through the electrostatic spinning process and spinning is higher in porosity and better in pore structure uniformity, so that the cathode gradient catalyst layer with pores in an increasing trend is formed, water-gas mass transfer of a fuel cell in a high-current density area is facilitated, and the cell performance is improved.

The invention provides a membrane electrode and a proton exchange membrane fuel cell, and particularly relates to the technical field of fuel cells. The membrane electrode comprises an anode gas diffusion layer, an anode catalyst layer, a proton exchange membrane, a cathode catalyst layer and a cathode gas diffusion layer which are sequentially stacked, and the anode gas diffusion layer comprises a hydrophilic microporous layer. According to the membrane electrode provided by the invention, the hydrophilic microporous layer is arranged in the anode gas diffusion layer, and water vapor generated by the anode catalyst layer is absorbed and transferred by the hydrophilic microporous layer at the first time and then is transferred and discharged by the hydrophobic microporous layer, so that water and gas on the anode side are uniformly distributed, water logging is avoided, and the gas mass transfer process on the anode side is improved; and normal operation of the membrane electrode is further ensured.

An electrolytic device, photoelectrode, and method for inducing an electrochemical reduction of a feed gas, comprising an anode and a hybrid cathode, the hybrid cathode comprising a cathode, a microporous layer disposed on one side of the cathode; a cathode catalyst positioned on the surface of the microporous layer, a gas channel fluidly connected to the microporous layer, containing a quantity of a feed gas, an electrolyte channel fluidly connected to the cathode catalyst containing a quantity of electrolyte, wherein the hybrid cathode is configured to induce an electrochemical reaction in the feed gas to produce methanol, and wherein the cathode catalyst comprises a compound represented by General Formula (I).

The invention relates to the technical field of fuel cells, and provides a method and a device for optimizing operation conditions of a proton exchange membrane fuel cell. The method comprises the following steps: simulating the proton exchange membrane fuel cell according to a local dimension reduction single cell model and initial operation conditions of the proton exchange membrane fuel cell to obtain initial effective output power; sequentially increasing each initial parameter value under the initial operation condition to obtain a target operation condition; simulating the proton exchange membrane fuel cell again according to the target operation condition and the local dimensionality reduction single cell model to obtain the target saturation of liquid water of the cathode catalyst layer and the target effective output power; and obtaining a performance evaluation value corresponding to the target operation condition according to the initial effective output power, the target effective output power and the target saturation degree of the liquid water of the cathode catalyst layer, so as to determine the target operation condition corresponding to the performance evaluation value as the optimal operation condition. By adopting the method, the precision of the performance evaluation value can be improved, and the optimization effect of the operation condition is further improved.

The invention belongs to the technical field of fuel cells, and relates to a microporous layer with a humidity self-adjusting function and a preparation method thereof, and the microporous layer with the humidity self-adjusting function is of a hydrophilic and hydrophobic mixed structure and is arranged between a cathode catalyst layer and a cathode gas diffusion layer. Comprising a carbon material, a hydrophobic polymer and a ceramic oxide modified by a sulfonic acid group, the proton exchange membrane fuel cell adopting the microporous layer has a humidity self-adjusting function during working; the preparation method comprises the following steps: uniformly dispersing a carbon material and a ceramic oxide modified by a sulfonic acid group in ethanol and / or isopropanol to obtain a dispersion liquid, adding a water repellent agent into the dispersion liquid, uniformly mixing to obtain a microporous layer slurry, and finally coating the microporous layer slurry on the gas diffusion layer to obtain the gas diffusion layer. And drying at a constant temperature to obtain the microporous layer with the humidity self-adjusting function. With the adoption of the microporous layer, the comprehensive performance and the long-term stability of the fuel cell can be remarkably improved; the preparation method is simple.

Provided is an electrolyte membrane with a catalyst layer, which is capable of suppressing a reduction in the output of a fuel cell while reducing the production cost. The present invention is a catalyst layer-equipped electrolyte membrane having a cathode catalyst layer on one surface of the electrolyte membrane and an anode catalyst layer on the other surface, the cathode catalyst layer and the anode catalyst layer each containing platinum, the electrolyte membrane has a transmittance ratio TR50 (TH50 / TO50) of hydrogen gas transmittance (TH50) to oxygen gas transmittance (TO50) at 65 DEG C and 50% RH of 3.0 or more, and satisfies the following condition 1 and / or condition 2. < Condition 1 > The ratio (CPt / APt) of the amount of platinum (CPt) per unit area of the cathode catalyst layer to the amount of platinum (APt) per unit area of the anode catalyst layer is 2.0 or more. < Condition 2 > The ratio TAn / TCa of the thickness (TCa) of the cathode catalyst layer to the thickness (TAn) of the anode catalyst layer is less than 0.40.

The invention discloses a method for preparing a membrane electrode through one-step two-section hot-pressing transfer printing. Comprising the following steps: S1, coating a first transfer printing substrate with cathode catalyst slurry to form a cathode catalyst layer, and coating a second transfer printing substrate with anode catalyst slurry to form an anode catalyst layer; s2, the first tiled layer, the second transfer printing base material with the anode catalyst layer, the proton exchange membrane, the first transfer printing base material with the cathode catalyst layer and the second tiled layer are sequentially stacked and tiled on a hot press, first hot pressing treatment and second hot pressing treatment are sequentially executed, and the cathode catalyst layer and the anode catalyst layer are arranged close to the proton exchange membrane; wherein the treatment pressure of the first hot-pressing treatment is smaller than that of the second hot-pressing treatment, and the treatment time of the first hot-pressing treatment is larger than or equal to that of the second hot-pressing treatment. According to the method, the initial pore structure of the catalyst layer can be reserved to the greatest extent while the transfer printing rate of the catalyst layer is improved, and the peak power density of the membrane electrode is improved.

The invention belongs to the technical field of lithium-carbon dioxide batteries, and particularly relates to a lithium-carbon dioxide battery positive electrode catalyst, a preparation method and a lithium-carbon dioxide battery. Comprising the following steps: taking iron, cobalt, nickel and copper as templates, respectively grinding and mixing with 1, 2, 4, 5,-tetracyanobenzene, sintering under a vacuum condition, respectively coordinating the 1, 2, 4, 5,-tetracyanobenzene with metal ions to form polymer monomers, and polymerizing the polymer monomers to form iron polyphthalocyanine, thereby obtaining the lithium-carbon dioxide battery positive electrode catalyst. The iron polyphthalocyanine is adopted as the positive electrode catalyst of the lithium-carbon dioxide battery, so that the generation of lithium oxalate is realized, the discharge voltage is improved to be higher than a theoretical value 3.01 V, the charging voltage is reduced, and the energy efficiency of the battery is improved.

The invention provides a rapid activation method of a proton exchange membrane fuel cell, and belongs to the technical field of fuel cells. The rapid activation method comprises a hydrogen pump activation stage and a variable load activation stage. In the hydrogen pump activation process, a current with the current density of 50-200mA / cm < 2 > is applied to the fuel cell in a constant current mode for 5-30 minutes, so that the utilization rate of an electrode catalyst is improved, and the generation of surface oxides of a cathode catalyst can be removed or avoided; in the variable load activation process, low current density and high current density are alternately changed, the ratio of the high current density to the rated current density of the battery is 0.8-1.2, and the ratio of the low current density to the high current density is less than or equal to 0.2, so that establishment of water, gas, electron and proton channels in the membrane electrode is facilitated. By adopting the activation method provided by the invention, the activation time of the proton exchange membrane fuel cell is effectively shortened, the hydrogen consumption is reduced, and the manufacturing cost of the fuel cell is reduced.

The invention discloses a layered structure solid oxide fuel cell composite cathode catalyst as well as a preparation method and application thereof, and belongs to the field of solid oxide fuel cells. The invention aims to solve the problem that the electro-catalytic performance and low-oxygen reduction reaction activation energy of the existing medium-temperature solid oxide fuel cell are poor. The Sr2. 9Ca0. 1Fe2O7-CuO composite cathode catalyst is prepared by adopting a sol-gel method and a solid phase method, the components in a sol-gel system are in a nanometer range, the reaction is easier to carry out, the reaction temperature is low, the prepared materials are uniformly mixed, and the sol-gel method is carried out in a solution, so that even if the content of doped elements is very low, the doping can be easily realized; the material is prepared by adopting a solid phase method, and the method has the advantages of convenience in operation, simple synthesis process, uniform particle size, no agglomeration of powder particles, good filling property, low cost, high yield and the like, so that the electrochemical performance of the cathode catalyst is improved, and the method is convenient to operate and suitable for industrial production.

The triangular runners are arranged on the inner sides of an anode plate and a cathode plate of the PEM electrolytic bath, the vertex angle is 30-90 degrees (preferably 45-60 degrees), the depth of each runner is 0.5-5 mm, the width of each runner is 0.5-5 mm, the interval of each runner is 1-10 mm, and the triangular runners can be arranged in parallel, staggered and the like. The anode plate and the cathode plate can be made of metal (such as stainless steel and titanium alloy) or graphite materials, and cooling channels can be arranged outside the anode plate and the cathode plate. The membrane electrode assembly comprises a proton exchange membrane (such as a perfluorosulfonic acid membrane), an anode catalyst layer (such as iridium dioxide) and a cathode catalyst layer (such as platinum or platinum alloy). According to the electrolytic cell, fluid disturbance is increased, gas discharge is improved, membrane electrode hydrogen attachment is effectively reduced, proton conduction and electrode reaction activity are improved, and compared with a traditional electrolytic cell, under the same condition, the current density, the hydrogen production efficiency and the hydrogen purity are higher, energy consumption and cost are lower, and good application prospects and economic benefits are achieved.

The invention provides a cathode catalyst for a fuel cell, a preparation method of the cathode catalyst and a membrane electrode containing the cathode catalyst, and relates to the technical field of fuel cells. According to the preparation method of the cathode catalyst for the fuel cell, a spherical urea-formaldehyde resin carbon carrier is adopted as a carbon carrier precursor, and the spherical urea-formaldehyde resin carbon carrier has the advantages of high mechanical strength and large packing density and also has rich surface functional groups and rich nitrogen elements. Therefore, the spherical urea-formaldehyde resin carbon is used as a carbon carrier precursor to synthesize the fuel cell catalyst, the obtained catalyst is high in mechanical strength and stable in structure, and the problem that pores of a catalyst layer become smaller in the hot pressing process of the fuel cell catalyst layer can be effectively solved. Besides, the cathode catalyst is prepared by adopting a microwave heating method, the obtained noble metal particles are small and uniform in particle size, relatively narrow in particle size distribution range and good in catalytic activity, and the microsphere morphology of the spherical urea-formaldehyde resin carbon can be fully reserved by adopting the microwave heating method.

A surface-modified catalyst, a multilayer cathode and a system for the electrochemical reduction of carbon dioxide in an acidic medium releasing protons are described. More particularly, the surface-modified catalyst, the multilayer cathode and the system comprise least one heterocyclic organic molecule preventing protons from accessing an active site on a surface of the cathode catalyst material to decrease an hydrogen evolution reaction, as compared to the absence of said heterocyclic organic molecule. The use of the surface-modified catalyst, the multilayer cathode and the system for the production of multicarbon products as well as their processes of manufacturing are also described. Finally, also described are methods for electrochemical production of a multicarbon product using the multilayer cathode and the system.

The invention discloses a preparation method of a cathode catalyst and a positive pole piece for a neutral zinc-air battery, and relates to the field of zinc-air batteries. The material of the catalyst is M-N-C (M is a transition metal), nitrogen is dissociated by discharging in a nitrogen atmosphere through a plasma ball mill, and metal particles separated from metal balls composed of M under high-speed impact are directly loaded on a highly dispersed carbon substrate through electric field adsorption. And carrying out high-temperature heat treatment on the mixed material subjected to the process in a tubular furnace under the protection of inert gas to obtain the target M-N-C catalytic material. When the M-N-C catalytic material provided by the invention is used as a cathode catalyst layer of the neutral zinc air battery, the reaction efficiency of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) can be effectively improved, the overpotential of the zinc air battery is reduced, the cycle stability of the neutral zinc air battery is improved, and the cycle life is prolonged.