37results about How to "Reduced mass transfer polarization" patented technology

The invention relates to an electrode of hydrocarbon produced by carbon dioxide through electrochemical reduction and a preparation and an application of the electrode. The electrode comprises a base layer, a thin-film layer and an ordered layer, wherein the thin-film layer is prepared from porous copper nanoparticles; the thin-film layer prepared from the porous nanoparticles is attached to the outer surface of a flake base layer; a copper whisker layer is attached to the surface of the thin-film layer prepared from the porous copper nanoparticles; the thickness of the base layer is 100-500 microns; the thickness of the porous nano thin-film layer is 100-200 microns; and the thickness of the copper whisker layer is about 100-500 microns. According to the electrode with the structure, the reaction activity area is effectively increased; mass transfer of a reactant is improved; and reduction of reaction polarization resistance and mass transfer polarization resistance is facilitated, so that the conversion efficiency of CO2 is improved; the selectivity of an ERC reaction product can be improved by regulating and controlling the active substances with different shapes; the stability of Cu metal can be improved by the structure; and the service lifetime of an ERC reaction catalyst is prolonged.

The invention relates to a carbon-sulfur compound for a positive electrode of a lithium-sulfur battery and a preparation and an application of the carbon-sulfur compound. The compound comprises a carbon material and elemental sulfur, wherein the carbon material has a gradient ordered three-level pore structure; the pore diameter distribution intervals of three-level pore channels are that micropores which are smaller than 2nm are taken as first-level pores, small mesopores which are about 3-10nm are taken as second-level pores and large mesopores which are 10-30nm are taken as three-level pores; the second-level pores are located in the walls of the third-level pores; the first-level pores are located in the walls of the second-level pores; pore channels of the carbon material are filled with the elemental sulfur; and the elemental sulfur accounts for 10-80wt% of total mass of the compound. The carbon-sulfur compound is applied to the lithium-sulfur secondary battery, is quite high in sulfur utilization rate and cycling stability and has the advantages of being simple in preparation process, good in repeatability, low in cost and micro-controllable.

The invention relates to a negative electrode for electroreduction of carbon dioxide and a preparation method thereof. The negative electrode is such structured that carbon paper, carbon felt or carbon cloth is used as a substrate; one side surface of the substrate is successively bonded with two catalysis layers of different pore sizes; and the negative electrode is successively composed of the substrate, a large-size heteroatom-doped nanocarbon layer and a small-size metal-and-heteroatom-doped nanocarbon layer. The large-size catalysis layer is favorable for transmission of CO2 and productsand reduction of mass transfer resistance; and the small-size heteroatom-doped nanocarbon layer is beneficial for improving the reaction active specific surface area of a catalyst and enhancing the reaction activity of the catalyst. As the negative electrode with such a structure is applied to ERC, the area of a three-phase electrochemical reaction interface is greatly broadened, the utilization rate of the catalyst is increased, and mass transfer polarization of an electrolytic bath is reduced; and in virtue of adsorptivity or formation of chemical bonds between the negative electrode and products of electroreduction of carbon dioxide, the selectivity and conversion rate of an assigned reduction product can be improved, and high selectivity of the reduction product is realized.

The invention relates to a gas diffusion electrode used for electrochemical reduction of carbon dioxide and a preparation method and an application of the gas diffusion electrode. The electrode comprises a base layer, and a Sn catalyst and an organic accessory ingredient mixing layer attached on the base layer; the molar ratio of the Sn catalyst to the organic accessory ingredient is 100:1 to 30:1; and the loading amount of the Sn catalyst in the electrode is 0.1-5mg/cm<-2>. In the electrochemical reduction of carbon dioxide, the base layer plays the effects of a supporting body, electric conduction, and forming liquid and gas transmission channels; the Sn catalyst catalyzes reduction of carbon dioxide while the organic accessory ingredient can stabilize an intermediate reactant CO<2>.-, so that the concentration of CO<2> is improved, overpotential in electrochemical reduction of carbon dioxide is lowered, and current density and efficiency are improved; and in addition, the accessory ingredient in the electrode also anchors the Sn catalyst on the surface of the carbon base, so that the electrode has quite high stability.

The invention relates to a preparation method of an alkaline anion exchange membrane, which comprises the following steps of: respectively dissolving an anion exchange resin precursor and a functionalization reagent in an oil phase and a water phase, carrying out functionalization reaction at a two-phase interface by using the resin precursor and the functionalization reagent, and carrying out in-situ self-assembly to form the membrane. According to the method, the problem of gel generated in a traditional homogeneous solution functionalization reaction is solved, and the prepared alkaline anion exchange membrane is high in ordering degree, has hierarchical pore distribution and is controllable in thickness; and the membrane has high ionic conductivity and good water transport characteristics, and has good performances when used in alkaline anion exchange membrane fuel cells.

The invention discloses a PEM water electrolysis proton membrane and CCM integrated preparation process and equipment, the equipment adopts a combination of multiple nozzles and a slit type coating head, the multiple nozzles can independently spray different components of a catalyst layer multi-component composite slurry within an ultra-short time, the spraying rate and atomization degree of the different components are accurately controlled, and the production efficiency is improved. The problem of poor dispersibility of different catalysts and binders in the catalyst slurry in the same solution is solved; the preparation process comprises the following steps of: sequentially compounding the base membrane pretreatment layer, the catalyst layer 1, the functional layer 1, the composite reinforced membrane, the functional layer 2, the catalyst layer 2 and the like on the substrate to realize the integrated preparation of the PEM water electrolysis composite reinforced membrane and the CCM catalyst layer; and finally, the PEM membrane electrode has relatively low surface resistance, relatively high conductivity, mass transfer rate and chemical durability, so that the cost of PEM electrolyzed water is reduced, and the service life is prolonged.

The invention discloses a cathode catalyst of proton film fuel battery in the electrochemical technique domain, which is characterized by the following: each composition and weight percentage is 1-50 percent Pt, 20-80 percent Zr1-xMxO2 and 10-50 C, wherein the x is mole rate between 0.1 and 0.5; the catalyst making method comprises the following steps: adapts soft chemical method to synthesize nanometer-level Zr1-xMxO2; mixing the nanometer-level Zr1-xMxO2 with nanometer-level Pt/C at mole rate of Pt:M=1:1-5. The invention reduces the electrochemical polarization, Ohm polarization and mass tr ansfer polarization effectively, which increases the catalytic efficiency to improve the battery property.

The invention relates to a single-layer gas diffusion layer for a fuel cell and a preparation method and application of the single-layer gas diffusion layer, the gas diffusion layer only comprises a microporous layer, the microporous layer takes a carbon material, a hydrophobic binder and a pore-forming agent as raw materials, carbon-free paper and a self-supporting microporous layer are prepared through dry-method mold pressing, and the single-layer gas diffusion layer has good hydrophobicity, gas permeability and conductivity, and the resistance of water discharge can be reduced, so that cathode flooding is relieved. The dry-method preparation avoids the defect that cracks are generated on the surface due to solvent volatilization in a wet method, so that water logging caused by water gathering at the cracks is avoided. According to the prepared carbon-free paper, the thickness and porosity of the self-supporting microporous layer are controllable, the preparation process is simple, and conditions are mild. When the carbon-free paper and the self-supporting microporous layer prepared by the method are used as gas diffusion layers of fuel cells, relatively good electrochemical performance is achieved. The novel single-layer gas diffusion layer has wide application value in the field of fuel cells.

The invention provides catalytic slurry, a membrane electrode and a preparation method and application thereof. The catalytic slurry comprises a component A and a component B, wherein the component Ais prepared from 0.5 to 1.2 parts by weight of a catalyst, 0.6 to 1.1 parts by weight of a stabilizer, 1.5 to 2.2 parts by weight of an antipole inhibitor, 0.9 to 1.3 parts by weight of a binding agent and 90 to 99 parts by weight of a solvent; the component B is prepared from the following components in parts by weight: 0.5 to 0.7 part of a catalyst, 0.39 to 0.94 part of a stabilizer, 1.7 to 2.02parts of an antipole inhibitor, 0.75 to 2.4 parts of a binding agent, 0.8 to 1.2 parts of an activating agent and 84.7 to 99.5 parts of a solvent. According to the invention, the catalytic slurry improves the platinum utilization rate, the hydrogen proton transfer rate and the electron transfer rate, reduces activation polarization, ohmic polarization and mass transfer polarization and improves the power density of a membrane electrode through stepped concentration distribution and addition of an activator.

The invention relates to a durable hydrogen fuel cell for a hydrogen energy automobile. The hydrogen fuel cell comprises an anode plate, a cathode plate and an electrolyte diaphragm, the electrolyte diaphragm is arranged between the anode plate and the cathode plate, collector plates are arranged on the outer sides of the anode plate and the cathode plate, and the two collector plates are arranged in parallel; a first adhesive film is adhered between the anode plate and the electrolyte diaphragm, and a second adhesive film is adhered between the electrolyte diaphragm and the cathode plate. According to the electrolyte diaphragm provided by the invention, the strength of the electrolyte diaphragm can be improved, and the electrical property of the electrolyte diaphragm can be improved by the high-ion-conductivity electrolyte diaphragm layer, so that the electrolyte diaphragm layer provided by the invention can meet the strength requirement and can also meet the electrical property requirement.