7results about How to "Improve proton conductivity" patented technology

This invention discloses a method for preparing an aramid nanofiber-reinforced perfluorosulfonic acid proton exchange membrane, comprising the following steps: S1, mixing aramid nanofibers, a membrane-forming solvent, potassium tert-butoxide, and methanol to obtain an aramid nanofiber dispersion; S2, mixing the aramid nanofiber dispersion and a perfluorosulfonic acid solution, stirring, and degassing to obtain a first mixed solution; S3, mixing the first mixed solution and a coagulant to obtain a second mixed solution, and coating the mixture to obtain a composite membrane; S4, allowing the composite membrane to stand, drying, and annealing to obtain an aramid nanofiber-reinforced perfluorosulfonic acid proton exchange membrane precursor; S5, post-processing the aramid nanofiber-reinforced perfluorosulfonic acid proton exchange membrane precursor to obtain the aramid nanofiber-reinforced perfluorosulfonic acid proton exchange membrane. The introduction of aramid nanofibers in this invention improves the mechanical stability, ion exchange capacity, water absorption swelling rate, and proton conductivity of the aramid nanofiber-reinforced perfluorosulfonic acid proton exchange membrane.

This invention discloses a polyaromatic hydrocarbon for preparing proton exchange membranes, its preparation method, and its application, belonging to the field of proton exchange membrane material preparation technology. This invention solves problems such as low molecular weight, uneven sulfonation, chain breakage in sulfonated polymers, poor dimensional stability, and poor mechanical properties in proton exchange membrane materials. Using aromatic monomers and 3,5-difluorotrifluoroacetophenone as raw materials, this invention employs a superacid-catalyzed Friedel-Crafts hydroxyalkylation reaction to prepare fluorinated aromatic polymers. Then, sulfonic acid groups are introduced onto the fluorinated aromatic polymers via nucleophilic substitution followed by sulfonation, preparing monosulfonated and disulfonated fluorinated sulfonic acid polymers. Proton exchange membranes are then prepared using these polymers as raw materials. The significant polarity difference between the hydrophobic fluorinated benzene ring side groups and the hydrophilic disulfonic acid groups in this invention is more conducive to forming a microphase separation structure and constructing continuous proton transport channels. Simultaneously, the hydrophobic fluorinated segments effectively suppress membrane swelling and improve its dimensional stability.

The application provides a carbon nanotube composite anti-poisoning cathode catalytic layer and a preparation method and application thereof. The cathode catalytic layer comprises a three-dimensional porous framework formed by carbon nanotube composites interwoven and jointed with each other, the carbon nanotube composite comprises multi-walled carbon nanotubes and an ionomer, the ionomer is uniformly dispersed on the outer wall of the multi-walled carbon nanotubes; a catalyst is distributed on the surface and inside of the three-dimensional porous framework; the tube diameter of the multi-walled carbon nanotubes is 40nm-80nm; the porosity of the catalytic layer is 50.4%-59.3%, and more than 95wt% of the ionomer contained is combined on the carbon nanotubes. The cathode catalytic layer of the application adopts large-diameter carbon nanotubes combined with ionomers, can significantly improve the proton conduction and oxygen transmission capacity of the cathode catalytic layer and reduce the poisoning effect of the ionomer on the catalyst, and enhance the effective efficiency and activity of the catalyst. In addition, the proton conduction capacity and operating power of the fuel cell under a high-temperature environment are enhanced.

The application relates to the technical field of polybenzimidazole, and discloses a polybenzimidazole copolymer, a novel proton exchange membrane and a preparation method and application thereof; the proton exchange membrane comprises a matrix and a proton active component; the matrix is a polybenzimidazole homopolymer; the proton active component is a polybenzimidazole copolymer; and the polybenzimidazole copolymer comprises a first structural unit and a second structural unit. The proton exchange membrane of the application adopts a polybenzimidazole homopolymer as the matrix, and simultaneously adopts a polybenzimidazole copolymer containing a nitrogen-containing heterocyclic structural unit as the proton active component, so that the proton exchange membrane of the application has higher acid loading capacity (especially phosphoric acid loading capacity) and proton conductivity, and simultaneously has good mechanical properties and dimensional stability.

This invention relates to the field of proton exchange membrane (PEM) preparation technology, and discloses a modified PAN and quercetin-doped sulfonated polyaryletherketone (PAEK) PEM, its preparation method, and its applications. The method includes the following steps: synthesizing sulfonated PAEK via monomer copolymerization; obtaining modified PAN by carboxyl modification of polyacrylonitrile (PAN); and then blending SPAEK, modified PAN, and quercetin to form a membrane. In this invention, the cyano groups of the modified PAN form an acid-base crosslinking network with the sulfonic acid groups of SPAEK to inhibit swelling, and its carboxyl groups participate in proton conduction; the polyphenolic hydroxyl groups of quercetin construct a hydrogen bond network to enhance structural density and act as a free radical scavenger to improve antioxidant stability. This invention, through the synergistic effect of the three components, successfully solves the technical problems of SPAEK membranes, such as difficulty in balancing proton conductivity and dimensional stability, and poor antioxidant performance. The resulting composite membrane possesses high proton conductivity, low swelling rate, and excellent oxidation stability, making it suitable for vanadium redox flow batteries.

The application discloses a kind of double wide area-high acid retention gel state mixed matrix PBI proton exchange membrane and its preparation method and application, the gel state proton membrane is by flexible zirconium-glutamic acid (L-Glu-Zr (P)) or UiO-66 series metal organic framework, polybenzimidazole (PBI), phosphoric acid and water composition, its preparation method includes: with polyphosphoric acid as solvent, under the protection of inert gas, aromatic tetraamine monomer, dicarboxylic acid phenyl monomer high-temperature polycondensation forms PBI polymer solution, adds metal organic framework particle and disperses uniformly, mixed solution is scraped on substrate and experiences from solution to gel state membrane The phase transition process;Proton exchange membrane prepared in the application all shows excellent acid retention capacity, proton transport characteristics, fuel cell performance and stability under the service window of double wide area (temperature-20~240 DEG C, humidity 0~80%RH), has very good application prospect in fuel cell field.

This invention discloses a PPTA / PFSA blend proton exchange membrane, its preparation method, and its application. The preparation method of the PPTA / PFSA blend proton exchange membrane includes the following steps: Under a nitrogen or inert gas environment and with stirring, perfluorosulfonic acid is added in batches to a first membrane-forming solvent and stirred until homogeneous. Then, a co-solubilizing salt is added and stirred until homogeneous to obtain solution B. p-phenylenediamine is added to solution B at 10–15°C and stirred until homogeneous to obtain solution C. A terephthaloyl chloride solution is poured into solution C at -10–0°C to undergo a low-temperature reaction, resulting in solution D. Polyvinylpyrrolidone is added and stirred until homogeneous to obtain a casting solution, wherein terephthaloyl chloride is dissolved in a second membrane-forming solvent to form a terephthaloyl chloride solution. After degassing the casting solution, it is poured onto a substrate, coated, exposed to air for at least 10 seconds, and then immersed in water for phase inversion to form a membrane, thus obtaining a PPTA / PFSA blend proton exchange membrane on the substrate. The preparation method of this invention can simultaneously improve the mechanical strength and proton conductivity of the proton exchange membrane.