CN-122025428-A - Preparation method and application of porous MXene/PVA composite electrode with high mechanical strength

Abstract

The invention discloses a preparation method and application of a porous MXene/PVA composite electrode with high mechanical strength. The preparation method comprises the steps of uniformly dispersing an MXene suspension and a PVA solution into a solvent to obtain uniform slurry, forming a film from the uniform slurry to obtain an MXene/PVA composite film, spreading the composite film on the surface layer of a hydrazine hydrate solution, and drying to obtain the porous MXene/PVA composite electrode with high mechanical strength, wherein the composite electrode formed by compositing PVA and MXene and the MXene sheet establish stable intermolecular hydrogen bonds, the interlayer interaction force of MXene is enhanced, so that the mechanical property of MXene is remarkably improved, and the aggregation of the MXene layer is effectively inhibited by the construction of a three-dimensional porous structure in the composite electrode, so that active sites are fully exposed to electrolyte ions, and the electrochemical property of the composite electrode is greatly improved.

Inventors

• ZHAO ZIFANG
• HUANG WEIFENG
• XU ZHILONG
• Feng Jingteng
• XU GUANGRI
• YANG LI
• CHENG YINFENG
• LI YUANCHAO

Assignees

• 河南科技学院

Dates

Publication Date

20260512

Application Date

20260312

Claims (7)

1. 1. A preparation method of a porous MXene/PVA composite electrode with high mechanical strength is characterized by comprising the specific preparation processes of uniformly dispersing an MXene suspension and a PVA solution into a solvent to obtain uniform slurry, forming a film from the uniform slurry to obtain an MXene/PVA composite film, then spreading the composite film on the surface layer of a hydrazine hydrate solution, and drying to obtain the porous MXene/PVA composite electrode with high mechanical strength, wherein the MXene/PVA composite electrode formed by compositing PVA and MXene and an MXene sheet establish stable intermolecular hydrogen bond, the interlayer interaction force of MXene is enhanced, so that the mechanical property of MXene is remarkably improved, and the aggregation of an MXene layer is effectively inhibited by the construction of a three-dimensional porous structure in the MXene/PVA composite electrode, so that an active site is fully exposed to electrolyte ions, and the electrochemical property of the MXene/PVA composite electrode is greatly improved.
2. 2. The method for preparing the high mechanical strength porous MXene/PVA composite electrode according to claim 1, which is characterized by comprising the following specific preparation steps: S1, respectively diluting a pure MXene suspension and a PVA solution by a solvent, mixing the diluted MXene colloid solution and the diluted PVA solution, performing ultrasonic treatment to obtain uniform slurry, and forming a film from the uniform slurry to obtain a MXene/PVA composite film; And S2, dropwise adding hydrazine hydrate on a carrier, spreading the MXene/PVA composite film obtained in the step S1 on a hydrazine hydrate solution, placing the carrier in a closed container, heating and preserving heat at 80-100 ℃ in a blast drying box, and obtaining the MXene/PVA composite electrode with high mechanical strength and a 3D porous structure after the heat preservation is finished.
3. 3. The method for preparing a porous MXene/PVA composite electrode with high mechanical strength according to claim 2, wherein the solvent in the step S1 has no side reaction with the electrode material and is volatile, and the solvent is one or more of deionized water, ethanol, acetone and N, N-dimethylformamide.
4. 4. The method for preparing a porous MXene/PVA composite electrode with high mechanical strength according to claim 2, wherein the film forming mode in the step S1 is one or more of vacuum filtration, spin coating, screen printing, dip coating, ink jet printing and spray pyrolysis.
5. 5. The method of manufacturing a porous MXene/PVA composite electrode of claim 2, wherein in step S1, the MXene is one or more of Ti 3 C 2 T x 、Ti 2 CT x and V 2 CT x .
6. 6. The method for preparing a porous MXene/PVA composite electrode with high mechanical strength according to claim 2, wherein the carrier, the electrode material and hydrazine hydrate in the step S2 have no side reaction, and the carrier is specifically a ceramic plate or agate.
7. 7. The application of the porous MXene/PVA composite electrode with high mechanical strength prepared by the method of any one of claims 1-6 in the preparation of a flexible supercapacitor.

Description

Preparation method and application of porous MXene/PVA composite electrode with high mechanical strength Technical Field The invention belongs to the technical field of flexible supercapacitors, and particularly relates to a preparation method of a porous MXene/PVA composite electrode with high mechanical strength and application of the porous MXene/PVA composite electrode in preparation of a flexible supercapacitor. Background The preparation of electrodes of flexible supercapacitors is an important content of research in the field of flexible electronics. At present, the conventional flexible supercapacitor electrode still faces the following two front problems of (1) low mechanical strength of the electrode, easy breakage or crease generation under external deformation, and (2) easy aggregation of single-layer or multi-layer MXene sheets due to interlayer force, which can seriously affect the electrochemical performance of the MXene film. In order to solve the technical problems, researchers actively develop researches on electrode materials of the flexible super capacitor in the field of the flexible super capacitor. Patent document CN202311730567.X discloses a stretchable degradable PVA/MXene/AgNW electrode and a preparation method thereof, specifically, a PVA/MXene/AgNW electrostatic spinning solution is prepared, a stretchable electrode is prepared by electrostatic spinning, the stretchable electrode is degraded, and a recyclable PVA/MXene/AgNW electrostatic spinning solution is formed again. The technology utilizes the degradability of PVA and the high conductivity of MXene/AgNW, improves the stretchability and the mechanical strength of the composite electrode by adding an adhesive, and adopts an electrostatic spinning technology to prepare the PVA/MXene/AgNW electrode, so that the process is relatively complex and the control difficulty is relatively high. The patent document CN202210353677.8 discloses a preparation method of a solid-state energy storage device taking MXene as an electrode PVA-based hydrogel as an electrolyte, which comprises the steps of 1, weighing 15% of PVA by mass, adding 85% of water by mass, heating and stirring at 90 ℃ until the PVA is completely dissolved, cooling, adding 4M protonic acid relative to the water under stirring, standing until defoaming, 2, injecting the obtained solution into an electrolyte mould, putting the electrolyte mould into a refrigerator lower layer for freezing for 20 hours, taking out the electrolyte mould, standing at room temperature for 3 hours, 3, repeating the step 2 of cooling and standing, taking out and demolding to obtain the PVA-based hydrogel electrolyte, and the solid-state energy storage device has the advantages of reasonable structure, excellent multiplying power performance, and relatively complex preparation process, compared with a corresponding water system MXene energy storage device. Patent document CN201610570545.5 discloses a graphene/MXene composite electrode material and application thereof, and the preparation method comprises the steps of uniformly mixing graphene oxide suspension and MXene material suspension, adding hydrazine hydrate for reduction, and then freeze-drying to obtain the graphene/MXene composite electrode material. When graphene and MXene are compounded, irregular MXene particle materials serving as an intercalator and a dispersing agent enter between graphene sheets, so that the agglomeration effect between the graphene sheets is overcome, and the available specific surface area of the graphene sheets is increased. In addition, the excellent hydrophilicity and conductivity of the MXene material can further improve the electrochemical performance and the capacitive deionization performance of the composite material. Patent literature of CN201810420857.7 discloses a hydrogel based on graphene/PVA, preparation and application thereof, the hydrogel is prepared from the prepared GO solution, borax, hydrazine hydrate solution and PVA solution through heating and stirring, and the hydrogel which can be used as a supercapacitor electrode is obtained by utilizing excellent conductivity and ductility of graphene, higher specific surface area and crosslinking between borax and PVA. The prepared hydrogel has higher power density, higher multiplying power performance and better cycle stability. The patent document CN202411728715.9 discloses a MXene-based electrode material based on hydrazine hydrate gas expansion auxiliary pore-forming, a preparation method and application thereof, and specifically comprises the steps of mixing a MXene-OH mixed solution with bacterial cellulose dispersion, vacuum filtering, performing vacuum constant-temperature drying to obtain a MXene-OH/BC film, paving the MXene-OH/BC film on the upper surface of a first ceramic plate dropwise added with a hydrazine hydrate solution, paving a second ceramic plate on the upper surface of the MXene-OH/BC film after the MXene-OH/BC film is completel