97results about How to "Improve proton conductivity" patented technology

The invention belongs to the field of polymer electrolyte membranes, and particularly relates to a benzimidazole micromolecule-based proton exchange composite membrane for electrolyzing water and a preparation method thereof. The preparation method comprises the following steps: firstly synthesizing 5, 5 '-bis [2-(2-hydroxy-5-sulfophenyl) benzimidazole], then synthesizing sulfonated polyetheretherketone, and finally preparing the proton exchange composite membrane based on benzimidazole micromolecules. The benzimidazole rigid rod-like micromolecules with sulfonic acid groups are designed and prepared by utilizing the advantages of heat resistance, acid resistance, alkali resistance and better dissolvability than PBI of the benzimidazole micromolecules, and the benzimidazole rigid rod-like micromolecules are added into a polymer matrix as a filler to prepare the composite membrane, so that the proton conductivity, the swelling resistance and the oxidation stability of the original polymer membrane are improved.

The invention discloses a preparation method of a self-humidifying membrane electrode of a proton exchange membrane fuel cell, relates to a preparation method of a membrane electrode, and aims to solve the technical problem of poor performance of the conventional self-humidifying membrane electrode. The method comprises the following steps: 1, synthesizing a COFs material by using 2, 4, 6-triformyl phloroglucinol and 2, 5-diaminobenzene sulfonic acid through a two-phase method; 2, preparing slurry a by using a Pt / C catalyst and a perfluorosulfonic acid ionomer solution; preparing self-humidifying catalyst layer slurry b from a COFs material, a Pt / C catalyst and a perfluorosulfonic acid ionomer solution; and 3, coating the slurry a on the anode surface of the proton exchange membrane, and coating the slurry b on the cathode surface to obtain the self-humidifying membrane electrode. According to the electrode, H2 / O2 is used as fuel, and the power density is 756.3 mW / cm < 2 > under the relative humidity of 20%; h2 / air is used as fuel, the power density is 437.8-879.7 mW / cm < 2 > under the relative humidity of 50%, and the material can be applied to the field of fuel cells.

The invention discloses a large-area two-dimensional polymer (two-dimensional polymer, 2DP) nanosheet-based proton exchange membrane (PEM), which is characterized in that an ionic 2DP nanosheet is used as a membrane main body material, an ionic polyelectrolyte is added as an intercalator, and the large-area PEM is prepared by a tape casting method after full mixing. The preparation method comprises the following steps: synthesizing an ionic group functionalized 2DP nanosheet solution by adopting a step-by-step single-phase polymerization method, dissolving polyelectrolyte in a proper solvent, fully mixing with the 2DP nanosheet solution according to a certain proportion, and preparing the 2DP-polyelectrolyte composite membrane by adopting a tape casting method. The preparation method is convenient, simple, controllable and convenient to operate. The prepared large-area 2DP-polyelectrolyte composite PEM has a large size (400cm < 2 >), excellent stability and extremely high proton conductivity.

The invention provides a proton exchange membrane, a preparation method thereof and a fuel cell, and relates to the technical field of fuel cells. The proton exchange membrane comprises a base material with a porous structure, pores of the base material contain active components, and the active components comprise a heteropolyacid modified MOF material and sulfonated polyfluorene biphenyl indole; the weight ratio of the heteropoly acid to the MOF material is 1: (1-3). The proton exchange membrane provided by the invention has the characteristics of excellent mechanical durability, high proton conductivity and ultra-thinness, and can improve the mechanical strength, ductility and chemical stability of the membrane while reducing the expansion of the membrane.

The invention belongs to the technical field of hydrogen bond organic framework materials, and relates to a three-component hydrogen bond organic framework material as well as a preparation method and application thereof, the chemical formula is {C26H21O12P4. (CH6N3). (C10H12N4). (H2O)} n, and n is a positive integer. A structural unit belongs to a triclinic system, a space group is P-1, a molecular formula is C37H41N7O13P4, and each repeating unit comprises a water molecule, a G < + > cation, a DBpy < 2 + > cation and a H5TPE < 3-> molecule; amino groups on G < + > cations, amino groups on DBpy < 2 + > cations, deprotonated HPO3-groups in H5TPE < 3-> molecules and unprotonated phosphonic acid groups have a synergistic effect, and water molecules form a two-dimensional hydrogen bond network. According to the three-component strategy, the chemical and structural diversity of HOFs is greatly expanded, and the material performance is remarkably improved.

The invention provides a choline chloride: urea deep eutectic solvent modified ZIF-8 high-temperature proton exchange membrane as well as a preparation method and application thereof, and belongs to the technical field of preparation of fuel cells and proton exchange membranes. The deep eutectic solvent and the zinc hydroxide nanowire membrane are compounded in situ through a suction filtration method, and then the deep eutectic solvent modified ZIF-8 high-temperature proton exchange membrane is prepared. In the ZIF-8 high-temperature proton exchange membrane, a zinc hydroxide nanowire membrane bears a choline chloride-urea deep eutectic solvent, so that the choline chloride-urea deep eutectic solvent is compounded into pores of ZIF-8 in situ, and the choline chloride-urea deep eutectic solvent is blocked in a ZIF-8 membrane to modify the inner wall; the preparation method is simple to operate, low in energy consumption and free of pollution, and the prepared ZIF-8 high-temperature proton exchange membrane can maintain stability, has extremely high proton conduction capacity and has very good practicability.

The invention belongs to the technical field of proton exchange membrane preparation methods, and relates to a method for preparing a proton exchange membrane through response surface optimization. According to the method, a single-factor extraction test is carried out by taking the mass fraction of a membrane casting solution containing liquid crystal performance, the pulling speed and the drying temperature as influence factors, the influence of the mass fraction of the membrane casting solution containing liquid crystal performance, the pulling speed and the drying temperature on the membrane thickness of the proton exchange membrane is determined, and a response surface method test is designed; the optimal process conditions for preparing the proton exchange membrane are determined as follows: the mass fraction of the membrane casting solution containing the liquid crystal performance is 2.08%, the pulling speed is 82.23 mm / min, the drying temperature is 60.30 DEG C, and the actual measured average value of the thickness of the proton exchange membrane obtained under the conditions for three times is 33 + / -1 [mu] m. The prepared proton exchange membrane has high proton conductivity, and the method is provided for improving the proton conductivity of the proton exchange membrane.

The invention discloses membrane electrode catalyst layer slurry, a preparation method thereof and application of the membrane electrode catalyst layer slurry in preparation of a proton exchange membrane fuel cell, and relates to a membrane electrode material. The catalyst layer slurry comprises a resin dispersion liquid and a catalyst pre-dispersion suspension liquid; the resin dispersion liquid comprises alkali metal ions and a perfluorinated sulfonic acid resin film solution, the molar ratio of-SO3H in the alkali metal ions and perfluorinated sulfonic acid resin powder is larger than or equal to 0.05 and smaller than 0.3, and the alkali metal ions are Cs < + > and / or Rb < + >. A small amount of alkali metal ions with large ion radius are added into the catalyst layer slurry, so that self-agglomeration among perfluorosulfonic acid resin molecules is effectively blocked, more catalyst-perfluorosulfonic acid resin interfaces are generated, the particle size of the catalyst slurry is effectively reduced, the content of free perfluorosulfonic acid resin is reduced, and the service life of the catalyst slurry is prolonged. The uniformity of the catalyst slurry is remarkably improved, and on a catalyst layer of the CCM, the roughness is reduced, large particles on the surface are reduced, and the performance of a membrane electrode is improved.

The invention discloses a side group functionalized fluorine-containing polymer, a preparation method of the fluorine-containing polymer, an ion exchange membrane and application. The fluorine-containing polymer is obtained through the reaction of the functionalized reagent and the sulfonamide resin which is easily dispersed in the solvent, the reaction yield is increased, the main chain of the fluorine-containing polymer is of a perfluoro structure, the end group of the side chain is phenyl containing a substituent group, and the chemical stability of the end group is improved through a substituent group with high steric hindrance or a substituent group with high electronegativity; the sulfonyl imide functional group of the ion exchange membrane prepared from the fluorine-containing polymer has relatively strong gas-phase acidity, and the ion transmission capability of the material at high temperature is improved, so that the proton conductivity of the ion exchange membrane is improved, and the fluorine-containing polymer is suitable for a fuel cell ion exchange membrane, an ion exchange membrane for water electrolysis and a flow battery diaphragm.

The invention discloses a polyvinylpyrrolidone-polyethersulfone high-temperature proton exchange membrane and a preparation method thereof, the polyvinylpyrrolidone-polyethersulfone high-temperature proton exchange membrane comprises a membrane main material and a dopant, the membrane main material comprises polyvinylpyrrolidone and polyethersulfone, and the dopant is a mixture of polyvinylpyrrolidone and polyethersulfone. The doping agent is amino silane coupling agent surface modified tin dioxide, and the addition mass ratio of the doping agent is 1%-4% based on the membrane main material. The inorganic doped polyvinylpyrrolidone-polyethersulfone membrane is obtained through film forming by a tape casting method, the preparation process is simple, the raw material cost is low, and the prepared inorganic doped membrane has the advantages of good mechanical strength, strong proton conduction capability and the like after being doped with phosphoric acid, and has wide application prospects in high-temperature proton exchange membrane fuel cells.

The invention relates to the technical field of ion exchange membranes of all-vanadium redox flow batteries, and discloses a cross-linked amino type polybenzimidazole composite membrane for a vanadium battery and a preparation method of the cross-linked amino type polybenzimidazole composite membrane. The preparation method comprises the following steps: S1, preparing an imidazole functional monomer 1 containing double bonds; s2, preparing a functional monomer 2 containing double bonds; step S3, preparing a cross-linked amino type polybenzimidazole solution; and step S4, preparing the cross-linked amino polybenzimidazole composite membrane. The composite membrane disclosed by the invention has a cross-linked structure, so that the acid absorption rate and the proton conductivity can be improved, the voltage efficiency of the vanadium battery can be improved, and the tensile strength and the mechanical stability of the membrane can also be improved; the nitrogen heterocyclic structure in the chain segment can inhibit vanadium ion permeation and improve coulombic efficiency.

The invention relates to the technical field of flow battery diaphragms, and discloses a polyamide-like covalent organic framework diaphragm for a vanadium battery and a preparation method of the polyamide-like covalent organic framework diaphragm. Comprising the following steps: preparing a porous base membrane; preparing covalent organic framework nanosheet dispersion liquid by a solvothermal oxidation method; preparing a two-phase solution of interfacial polymerization; and preparing the polyamide-like covalent organic framework diaphragm. The processability of the covalent organic framework can be improved by a solvothermal oxidation method. The polyamide-like covalent organic framework diaphragm has high porosity, and pore channels are rich in sulfonic acid groups, so that the proton conductivity of the diaphragm can be improved. In addition, the polyamide-like covalent organic framework diaphragm has intrinsic pore channels of a covalent organic framework and polyamide pore channels, the effective pore diameter is reduced through a hierarchical pore effect generated by staggered arrangement of the intrinsic pore channels and the polyamide pore channels, and the ion selectivity of the diaphragm and the coulombic efficiency of the battery are improved.

The invention relates to a catalyst layer and a preparation method thereof, a membrane electrode and a fuel cell, the catalyst layer comprises a catalyst layer substrate and an active layer attached to at least part of the surface of the catalyst layer substrate, the active layer comprises hydrophilic regions and hydrophobic regions, and the hydrophilic regions and the hydrophobic regions are alternately arranged in a layered manner; wherein the raw material component of the hydrophobic region comprises a porous long-chain imidazole imine ionic liquid. The hydrophilic region has the effect of conducting protons and reaction gas, and due to the fact that the long-chain imidazole imine ionic liquid contains holes, under the effect of certain gas pressure, water generated by the catalyst layer can be preferentially discharged from the hydrophobic region containing the holes, and the reaction gas can enter from the hydrophilic region beside the hydrophilic region, so that the reaction gas can be discharged from the hydrophobic region containing the holes. Therefore, the purpose of surface ordering of the catalyst layer with independent water and gas transmission channels is achieved, and the catalyst layer also has good gas transmission capacity while the hydrophobicity of the catalyst layer is improved.

The invention provides a preparation method of a UiO-66-NH2-HSO3 / chitosan composite material, which comprises the following steps: simultaneously loading acid-base groups-NH2 / -HSO3 on a Zr-based metal-organic framework material by using a hydrothermal method to prepare a UiO-66-NH2-HSO3 framework material; and compounding the framework material with chitosan to obtain the UiO-66-NH2-HSO3 / chitosan composite material. The UiO-66-NH2-HSO3 / chitosan composite material disclosed by the invention can be used for a proton exchange membrane fuel cell, chitosan and UiO-66-NH2-HSO3 are compounded, so that the membrane material has relatively good water stability and mechanical tensile property, the chitosan has a long-chain structure,-NH2 is spread over the surface of the chitosan, a hydrogen bond network with higher density and more complex is formed in the whole membrane, and the performance of the membrane is improved. The acid-base pair effect is promoted, so that higher proton conduction performance is realized. Compared with other proton conductive materials, the UiO-66 series MOF disclosed by the invention is relatively mature, and the chitosan is relatively low in cost, so that the UiO-66 series MOF has a relatively good industrial utilization value.

This invention discloses a method for preparing a Pt / C catalyst by vacuum impregnation with an ionic liquid and its application. First, a carbon support is mixed with water and alcohol, ball-milled, and then mixed with nitric acid to obtain an acid-treated carbon support. Next, a precursor solution is prepared by mixing a platinum salt, an organic solvent, a surfactant, and water, and then an imidazole ionic liquid is added to it in portions to obtain a precursor solution containing the ionic liquid. This solution is mixed with the acid-treated carbon support and vacuum ball-milled to obtain a mixed slurry. This slurry is then vacuum freeze-dried to obtain a freeze-dried powder. Reduction and heat treatment are then performed to obtain the ionic liquid-doped Pt / C catalyst. The catalyst is then coated onto both sides of a proton exchange membrane to form a catalytic layer. Through this method, this invention not only effectively inhibits the aggregation, migration, and ripening of platinum particles during electrochemical processes, thereby significantly improving the catalyst's durability, but also enhances the catalyst's proton conductivity under low humidity conditions.

The invention relates to a nitro-containing carbon chain polymer, a polymer binder, a polymer film and application of the nitro-containing carbon chain polymer, the nitro-containing carbon chain polymer is prepared by Friedel-Crafts reaction of raw materials such as a nitrogen heterocyclic monomer, an aromatic monomer and a nitro-containing ketone monomer, and the nitro-containing carbon chain polymer contains nitro, so that free radicals can be quenched, and the nitro-containing carbon chain polymer can be used as a polymer binder. The free radical resistance of the polymer is improved, so that the damage of hydroxyl radicals to the polymer is relieved, and the stability of the polymer is improved. The ion exchange membrane or ionomer adhesive prepared from the nitro-containing carbon chain polymer has excellent free radical resistance.

The invention relates to a preparation method of a multifunctional composite proton exchange membrane, and aims to design a special membrane for electrochemical equipment such as a fuel cell and a water electrolysis device so as to improve the proton conduction efficiency and chemical stability of the electrochemical equipment. In an experiment, the polyether sulfone proton exchange membrane is prepared through an optimized electrostatic spinning process, and nanofibers with a high specific surface area and a specific pore structure are formed, so that the proton exchange capacity and the mechanical stability of the membrane are enhanced. The invention also covers a preparation method of the membrane, in which sulfonated polyethersulfone is dissolved in a suitable solvent, a nanofiller and a suitable tackifier are added, electrostatic spinning is carried out by adjusting parameters such as voltage, flow rate and collection distance, and then heat treatment and chemical treatment steps are carried out to optimize the performance of the membrane. The preparation method is characterized in that the mechanical strength, the chemical stability and the proton conductivity of the membrane are remarkably improved by applying an electrostatic spinning technology and adding a modified material, and the membrane can keep excellent performance even under harsh operation conditions, so that the membrane becomes an ideal choice for high-efficiency electrochemical application. According to the invention, the performance and the stability of the electrochemical equipment are obviously improved, and important technical support is provided for promoting the development and the application of the electrochemical field.

The invention provides a perfluorosulfonic acid resin without perfluorooctanoic acid or perfluorooctane sulfonic acid, a preparation method thereof, a catalyst layer and a hydrogen fuel cell membrane electrode. The perfluorinated sulfonic acid resin is formed by copolymerization of monomers containing perfluorinated oxaolefin sulfonyl fluoride and water-soluble perfluorinated oxaolefin sulfonate through an emulsion method, and the perfluorinated oxaolefin sulfonate is obtained by hydrolysis of the perfluorinated oxaolefin sulfonyl fluoride through alkali liquor. The mass ratio of the perfluorinated oxaolefin sulfonyl fluoride to the perfluorinated oxaolefin sulfonate is (4-8): 1. The perfluorinated oxaolefin sulfonate is a double-bond-containing perfluorinated surfactant, can be used as an emulsifier and can also be used as an active polymerizable monomer to participate in a polymerization reaction, and compared with resin which does not contain a double-bond emulsifier in the prior art, the perfluorinated sulfonic acid resin disclosed by the invention has the advantages of higher resin purity and lower cost. The composite material has good proton conductivity, oxygen permeability, mechanical strength, durability and the like.

The invention belongs to the technical field of proton exchange membranes and provides a post-treatment process of a composite proton exchange membrane. The post-treatment process comprises: placing the composite proton exchange membrane in a non-ionic surfactant for cleaning, placing the composite proton exchange membrane in an ion exchange agent for waiting for 0.5 hours after drying treatment, placing the composite proton exchange membrane in a neutralizing solution for soaking for 0.5 hours, then drying treatment, finally cleaning the surface of the composite proton exchange membrane and coating it with a graphene oxide coating, and curing the surface coating of the composite proton exchange membrane after drying treatment. The present invention stabilizes the performance of the composite proton exchange membrane by using a non-ionic surfactant and thoroughly cleans the impurities remaining on the surface of the composite proton exchange membrane, ensuring that no influence is caused on the subsequent hardening treatment, and then the non-ionic surfactant remaining on the surface of the composite proton exchange membrane accelerates the coagulation and hardening of the composite proton exchange membrane, thereby improving the performance of the proton exchange membrane, such as ion exchange capacity, proton conductivity, chemical stability, etc.

The invention discloses a porous polybenzimidazole / proton conductor type polyamide composite ionic membrane as well as a preparation method and application thereof, and belongs to the technical field of polymer electrolyte membranes. The preparation method specifically comprises the following steps: blending proton conductor type polyamide, polybenzimidazole and an organic solvent to form a uniform system, then adding an organic pore-forming agent, pouring the volatile solvent to form a membrane, and finally soaking in acid liquor to obtain the porous polybenzimidazole / proton conductor type polyamide composite ionic membrane. The proton conductor type polyamide synthesized by the invention has certain proton conductivity, and the intrinsic proton conductivity of the ionic membrane can be improved by adding the proton conductor type polyamide into the polybenzimidazole ionic membrane instead of more dependence on adsorption of acids (including phosphoric acid, sulfuric acid and the like). Besides, due to the addition of the triethanolamine pore-forming agent, a tiny and disconnected porous structure can be formed in the ionic membrane, and higher acid absorption is obtained on the premise of ensuring the air tightness and high vanadium resistance of the ionic membrane, so that higher proton conductivity is obtained.

The invention belongs to the technical field of fuel cell proton exchange membranes, and discloses a cross-linking type polybenzimidazole proton exchange membrane with oxidation resistance and high proton conductivity and a preparation method of the cross-linking type polybenzimidazole proton exchange membrane. According to the cross-linking type polybenzimidazole, after polymerization of raw material monomers is completed, a silane coupling agent is added as a cross-linking agent, and polybenzimidazole containing the cross-linking agent is obtained through reaction. The polybenzimidazole containing the cross-linking agent can be prepared into a cross-linking type polybenzimidazole proton exchange membrane by using a solution casting method. According to the cross-linked polybenzimidazole disclosed by the invention, a stable and uniform Si-O-Si cross-linked network is constructed by adding the cross-linking agent and taking a hydroxyl group on the polybenzimidazole as a main reaction site, so that synchronous improvement of antioxidant stability and proton conductivity is synergistically realized. The polybenzimidazole proton exchange membrane containing the cross-linking agent has a good application prospect in the aspect of proton exchange membrane fuel cells.

[Task] Provided is an electrochemical cell, a power generation method using the electrochemical cell, and a manufacturing method of a hydrogen gas using the electrochemical cell that are suitable for the use in a temperature range between 200°C and 600°C. [Solution] A fuel cell 1 (electrochemical cell) includes a proton conductor 5 represented by (Li, H)14-2xZn1+x(GeO4)4 where a portion of lithium ions of Li14-2xZn1+x(GeO4)4 where x is a number equal to or more than 0 is substituted with protons, the proton conductor having electric conductivity of 0.01 S / cm or more at 300°C, an anode 6 provided on one side of the proton conductor, a cathode 7 provided on another side of the proton conductor, a first separator 9 provided on an anode side of the proton conductor to define an anode chamber 8, and a second separator 12 provided on a cathode side of the proton conductor to define a cathode chamber 11.

The invention provides a preparation method of a PEM water electrolysis membrane electrode, which relates to the field of PEM water electrolysis hydrogen production. Titanium dioxide nanotubes are used as supporting materials to prepare an anode diffusion layer. Because the tube structure has high gas and liquid conductivity, it is beneficial to the separation of oxygen and water in the water electrolysis process. The titanium dioxide nanotubes are calcined at high temperature to transform into a rutile lattice structure, which has high conductivity and stability. The anode diffusion layer is prepared by stacking multiple thin single-layer supporting layers, and the porosity can be controlled within a suitable range. The anode diffusion layer has higher mechanical strength, plays a supporting role, meets the mechanical strength requirements of the water electrolyzer during operation, has higher porosity, and can effectively improve the transmission of water and gas between layers. The precious metal undergoes a solid phase reaction to be embedded in the surface of the rutile titanium dioxide nanotubes to form a dense catalytic conductive network structure, which is not easy to fall off, and can realize the batch preparation of membrane electrodes.

The invention discloses a cross-linked polymer-molecular cluster non-fluorine composite proton exchange membrane and a preparation method and application thereof, the cross-linked polymer-molecular cluster non-fluorine composite proton exchange membrane is mainly prepared from branched polyethyleneimine (PEI), polyvinyl chloride (PVC) and phosphotungstic acid (PW12), quaternized PEI and PVC are subjected to a cross-linking reaction, and then the prepared membrane is immersed in a PW12 solution to prepare the cross-linked polymer-molecular cluster non-fluorine composite proton exchange membrane. Wherein the mass ratio of the PEI to the PVC can be adjusted as required, the mass fraction of the PW12 solution is preferably 5-20%, the proton exchange membrane has good mechanical properties, thermal stability and excellent proton conductivity, and the preparation method is simple, low in cost and environmentally friendly.

The invention relates to an ionic liquid covalently grafted hexagonal boron nitride composite proton exchange membrane as well as a preparation method and application thereof. The ionic liquid covalently grafted hexagonal boron nitride composite proton exchange membrane is prepared from the following raw materials: Nafion resin and ionic liquid covalently grafted hexagonal boron nitride. The ionic liquid in the ionic liquid covalently grafted hexagonal boron nitride can convey protons to adjacent proton acceptors to complete proton conduction, so that the electrochemical performance of the composite membrane is improved; hexagonal boron nitride can improve the mechanical property and stability of the proton exchange membrane, through covalent grafting with the ionic liquid, uniform dispersion of hexagonal boron nitride nanosheets in a polymer matrix can be improved, the overall uniformity of the proton exchange membrane is improved, and meanwhile, the problem of unstable membrane performance caused by leaching of the ionic liquid is avoided; the proton conductivity, the mechanical strength, the antioxidant stability and the thermal stability of the proton exchange membrane are improved.

The invention discloses a composite proton exchange membrane as well as a preparation method and application thereof. The composite proton exchange membrane is prepared by compounding an organic phosphonic acid functionalized porous silicon material and a polymer matrix and soaking in phosphoric acid, the organic phosphonic acid functionalized porous silicon material is organic phosphonic acid modified porous silicon; the polymer matrix is selected from at least one of polysulfone, polyether-ether-ketone, polyimide, polybenzimidazole and polyphenylene sulfide sulfone. The organic phosphonic acid functionalized porous silicon material is used as a doping material in the polymer membrane, and the material can improve the water and acid retention performance of the composite membrane and can also improve the proton conduction activity and high-temperature battery performance of the composite membrane. The prepared phosphoric acid-doped organic phosphonic acid functionalized porous silicon-doped polymer composite high-temperature proton exchange membrane has relatively high proton conductivity at 100-200 DEG C, and has relatively strong phosphoric acid interception capability, and a battery assembled based on the membrane can stably operate at 100-200 DEG C.

The invention discloses a sulfonated fluorine-containing polyimide-metal organic framework composite membrane as well as a preparation method and application thereof, and belongs to the technical field of all-vanadium redox flow battery diaphragms. The method comprises the following steps: synthesizing sulfonated fluorine-containing polyimide FSPI by using a high-temperature one-step method; preparing a metal organic framework MIL-101 (Cr) by adopting a hydrothermal method; the preparation method comprises the following steps: preparing a metal organic framework alpha-Fe2O3 / MIL-101 (Cr) by adopting a hydrothermal method; and preparing the sulfonated fluorine-containing polyimide-metal organic framework composite membrane FSPI / alpha-Fe2O3 / MIL-101 (Cr) by adopting a tape casting method. An ion transmission channel is regulated and controlled by introducing a metal organic framework alpha-Fe2O3 / MIL-101 (Cr) into sulfonated fluorine-containing polyimide. And the regulated ion transmission channel is larger than hydrated protons (lt, 0.24 nm) and smaller than hydrated vanadium ions (gt, 0.6 nm), so that the ion selectivity of the sulfonated fluorine-containing polyimide diaphragm is improved. The composite membrane prepared by the invention has high proton conductivity, good vanadium resistance and excellent ion selectivity. When the prepared composite membrane is used in the all-vanadium redox flow battery, the cycling stability of the battery is improved.

The present invention discloses a composite proton exchange membrane, which comprises a matrix and a filler; the matrix comprises sulfonated polyetheretherketone; the filler comprises sulfonated ZIF-derived porous carbon material and sulfonated carbon nanotubes. The composite proton exchange membrane provided by the present invention has the advantages of low methanol permeability, low swelling rate and high proton conductivity. By filling the sulfonated ZIF-derived porous carbon material and sulfonated carbon nanotubes, the proton conductivity of the composite proton exchange membrane can be improved, and the penetration of fuel can be blocked at the same time; the present invention overcomes the disadvantage of the instability of zinc-based ZIF in an acidic environment by carbonizing the zinc-based ZIF, making it suitable for preparing the composite proton exchange membrane; the preparation method of the composite proton exchange membrane is simple, efficient, low-cost, and has the advantage of being industrially produced; the composite proton exchange membrane can be widely used in fuel cells.

The invention discloses a composite proton exchange membrane and a preparation method thereof, the composite proton exchange membrane comprises a base membrane, a first coating and a second coating, the first coating and the second coating are coated on two sides of the base membrane, the first coating comprises polyvinyl alcohol and perfluorinated sulfonic acid resin, and the second coating comprises polyvinyl alcohol and perfluorinated sulfonic acid resin. The thickness of the composite proton exchange membrane is 20-80 [mu] m, the thickness of the first coating is 2-38 [mu] m, and the thickness of the second coating is 2-38 [mu] m. According to the invention, the base membrane is used as a supporting material, relatively high mechanical properties are provided, a proton transmission channel is provided through the polyvinyl alcohol composite perfluorosulfonic acid, and extremely strong hydrogen bond interaction exists between molecules and in molecules of polyvinyl alcohol, so that the membrane has excellent proton conduction performance, and the performance of the membrane is improved. Meanwhile, due to the introduction of polyvinyl alcohol, the perfluorosulfonic acid and the base membrane have good binding capacity. The barrier property of the composite proton exchange membrane on hydrogen permeation is synergistically improved.

This invention discloses a PPTA-modified perfluorosulfonic acid proton exchange membrane and its preparation method. The PPTA-modified perfluorosulfonic acid proton exchange membrane has a layered structure, with the middle layer being a mixture of perfluorosulfonic acid polymer and PPTA. The preparation method of the perfluorosulfonic acid polymer and PPTA mixture includes: mixing a pore-forming agent, PPTA resin, and concentrated sulfuric acid, stirring until the pore-forming agent and PPTA resin are uniformly dispersed in the concentrated sulfuric acid, and then vacuum degassing to obtain a PPTA porous casting solution; coating the PPTA porous casting solution onto a substrate, immersing it in pure water, and after solidification, peeling it off from the substrate, and then immersing it in ultrafiltration water to obtain a PPTA porous membrane; immersing the PPTA porous membrane in the perfluorosulfonic acid casting solution, and then drying it to obtain the perfluorosulfonic acid polymer and PPTA mixture layer. The perfluorosulfonic acid polymer and PPTA mixture layer can improve the thermal stability, mechanical strength, and swelling resistance of the membrane, and also has the advantage of reducing methanol permeability. It also increases the proton conductivity of the composite membrane.