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CN-121983746-A - Application of polyimide covalent organic framework material in water-based zinc-iodine battery diaphragm and anode

CN121983746ACN 121983746 ACN121983746 ACN 121983746ACN-121983746-A

Abstract

The invention provides an application of a polyimide covalent organic framework material in a water system zinc-iodine battery diaphragm and an anode, wherein TPDA-PMDA-COF prepared from N, N, N ', N' -tetra (4-aminophenyl) -1, 4-phenylenediamine and pyromellitic dianhydride is simultaneously used as a diaphragm modified functional layer and an anode iodine carrier, so that one material is dual-purpose, and a composite diaphragm and a composite anode prepared based on the material can cooperatively solve the core problems of multi-iodide shuttling, active substance loss and the like of the water system zinc-iodine battery.

Inventors

  • YANG WEITING
  • LIANG YUBO
  • WANG JIANYI
  • GAO YANAN
  • HU HUI
  • SU XIAOFANG

Assignees

  • 海南大学

Dates

Publication Date
20260505
Application Date
20260226

Claims (10)

  1. 1. The application of the polyimide covalent organic framework material in the water-based zinc-iodine battery diaphragm and the anode is characterized in that the polyimide covalent organic framework material is used as a modified functional layer of the water-based zinc-iodine battery diaphragm and an iodine carrier of the anode.
  2. 2. The use according to claim 1, wherein the polyimide covalent organic framework material is TPDA-PMDA-COF prepared by imidization of N, N, N ', N' -tetrakis (4-aminophenyl) -1, 4-phenylenediamine and pyromellitic dianhydride.
  3. 3. The use according to claim 2, wherein the polyimide covalent organic framework material is prepared with the parameters of molar ratio of N, N, N ', N' -tetrakis (4-aminophenyl) -1, 4-phenylenediamine to pyromellitic dianhydride of 1:2-2.5, imidization reaction temperature of 180-200 ℃ and reaction time of 100-200 hours.
  4. 4. The method of claim 1, wherein the polyimide covalent organic framework material has a BET specific surface area of at least 1700m 2 g -1 , a pore volume of at least 1.20cm 3 g -1 , a pore size highly concentrated at 2.89nm, and an iodine vapor adsorption of at least 2200mg g -1 .
  5. 5. The application of claim 1, wherein the polyimide covalent organic framework material has a capacity of 0.05-2mg cm -2 in the membrane modified functional layer and an iodine capacity of 15mg cm -2 or more in the positive electrode as an iodine carrier.
  6. 6. The use according to claim 1, wherein the membrane is one of a glass fiber membrane, a polypropylene membrane or a cellulose membrane, the polyimide covalent organic framework material is supported on the surface or inside of the membrane in a coating or composite form, and the thickness of the coating is 25-50 μm, so that the composite membrane is formed.
  7. 7. The application of the composite anode material disclosed in claim 1, wherein the anode is prepared by mixing a composite anode material formed by compounding the polyimide covalent organic framework material with iodine, a conductive agent and a binder, and the binder is one or a combination of more of polyvinylidene fluoride, polytetrafluoroethylene and polyaniline.
  8. 8. An aqueous zinc-iodine battery separator characterized in that the separator is a composite separator loaded with the polyimide covalent organic framework material of any one of claims 1 to 6.
  9. 9. An aqueous zinc-iodine battery positive electrode, characterized in that the positive electrode comprises the polyimide covalent organic framework material of any one of claims 1 to 5 and 7 as a host or carrier for iodine or iodine-based active substances.
  10. 10. An aqueous zinc-iodine battery comprising a zinc or zinc alloy negative electrode, an electrolyte, the separator of claim 8, and the positive electrode of claim 9, wherein the electrolyte comprises an aqueous solution of a soluble zinc salt and an iodine/iodide additive.

Description

Application of polyimide covalent organic framework material in water-based zinc-iodine battery diaphragm and anode Technical Field The invention relates to the technical field of new energy batteries, in particular to application of a polyimide covalent organic framework material in a water-based zinc-iodine battery diaphragm and an anode. Background As a novel water-based secondary battery, the water-based zinc-iodine battery (aqueouszinc-iodinebatteries, zn-I 2 battery for short) has the remarkable advantages of high safety, low cost, high theoretical energy density (the theoretical specific capacity based on iodine is 211mAh/g, and 422mAh/g under double-electron transfer), environmental friendliness and the like, the theoretical specific capacity of a zinc cathode is as high as 820mAh/g, the volume capacity density is as high as 5855mAh/cm 3, and zinc and iodine resources are abundant and widely distributed, so that the water-based zinc-iodine battery is regarded as an ideal candidate technology for large-scale power grid energy storage and renewable energy integration. Compared with the traditional lithium ion battery, the aqueous electrolyte is nonflammable, avoids the risk of thermal runaway, has moderate oxidation-reduction potential, higher theoretical voltage platform, good reaction reversibility and higher power density potential compared with other aqueous zinc ion batteries (such as zinc-manganese and zinc-vanadium systems). However, practical applications of aqueous zinc-iodine batteries still face a number of key technical challenges, mainly arising from the conversion reaction mechanism of the iodine positive electrode. During charging, the polyiodides formed are readily soluble in aqueous electrolytes and diffuse towards the zinc negative electrode, resulting in a severe polyiodide shuttle effect (polyiodide shuttle effect), causing loss of active species, self-discharge, low coulomb efficiency (typically < 98%) and rapid capacity decay. Meanwhile, iodine species are poor in conductivity, slow in reaction kinetics and easy to polarize under high load, and polyiodides react with zinc on the negative electrode side to further exacerbate zinc negative electrode corrosion, hydrogen evolution side reaction (HER) and dendrite growth. These problems do not meet the practical performance requirements of aqueous zinc-iodine batteries for high area capacity, high current density and long cycling. Polyimide-based COF (PI-COF) has shown the application advantage of carbonyl active sites in the positive electrode of zinc ion batteries as a class of COF materials with high stability and high specific surface area, but has not been developed for dual-function application in aqueous zinc-iodine batteries. The full imide structure has the characteristics of rigid framework and chemical corrosion resistance, so that the stability of the material in a water system environment can be remarkably improved, compared with the traditional imide or other organic frameworks, the full imide COF has stronger swelling resistance and structural retention capacity in electrolyte, is beneficial to maintaining the integrity and the functionality of a diaphragm in the long-term operation process of a battery, and is an important direction for constructing a high-performance COF material. Therefore, a novel technical scheme is needed in the art, and the same polyimide-based COF material is utilized to simultaneously realize positive electrode high-efficiency iodine load/rapid reaction kinetics and membrane low-load high-efficiency multi-iodide shuttle inhibition so as to cooperatively solve the core technical bottleneck of the water-based zinc-iodine battery and improve the overall energy density, the circulation stability and the industrial applicability of the battery. Disclosure of Invention In view of the above, the present invention proposes an application of a polyimide covalent organic framework material in a water-based zinc-iodine battery separator and a positive electrode, which solves the above-mentioned problems. The technical scheme of the invention is realized by applying the polyimide covalent organic framework material to the water-based zinc-iodine battery diaphragm and the anode, and simultaneously using the polyimide covalent organic framework material as a modified functional layer of the water-based zinc-iodine battery diaphragm and an iodine carrier of the anode. Preferably, the polyimide covalent organic framework material is a crystalline material prepared by solvent thermal imidization reaction of tetramine monomer N, N, N ', N' -tetra (4-aminophenyl) -1, 4-phenylenediamine (TPDA) and dianhydride monomer pyromellitic dianhydride (PMDA), and is named TPDA-PMDA-COF. Preferably, the materials are prepared with a molar ratio of TPDA to PMDA of 1:2 to 1:2.5 and are reacted at a temperature of 180 ℃ to 200 ℃ for 100 to 200 hours. Too short a reaction time may result in incomplete reaction and waste of a lar