CN-122025596-A - SnO (tin oxide)2Preparation method and application of/MOF-5 composite anode material

Abstract

The invention belongs to the technical field of preparation of electrode materials, and discloses a preparation method and application of a SnO 2 /MOF-5 composite anode material, wherein the preparation method comprises the steps of preparing SnO 2 /MOF-5 composite materials with different loading amounts of SnO 2 by a solvothermal method, cooling a sample to room temperature, washing, and vacuum drying to obtain SnO 2 /MOF-5, wherein SnO 2 nano particles are attached to the matrix MOF-5. When in use, the SnO 2 /MOF-5 composite material is uniformly coated on the surface of the zinc sheet by a doctor blade coating method. The material can be used as an electrode in an aqueous zinc ion battery. The material can effectively inhibit the negative side reaction of the water-based zinc ion battery.

Inventors

• YUAN AIHUA
• WU LITING
• XUE YUTAO
• MENG CHUNFENG

Assignees

• 江苏科技大学

Dates

Publication Date

20260512

Application Date

20260313

Claims (10)

1. 1. The SnO 2 /MOF-5 composite anode material is characterized by comprising a metal-organic framework material MOF-5 and a zinc-philic metal oxide SnO 2 ,SnO 2 which are attached to the surface of the MOF-5.
2. 2. The method for preparing the SnO 2 /MOF-5 composite anode material according to claim 1, comprising the steps of: And adding zinc nitrate hexahydrate into a reaction bottle, stirring and dissolving the zinc nitrate hexahydrate, sequentially adding terephthalic acid, triethylamine and stannous chloride dihydrate into the solution, stirring and dissolving the solution, transferring the mixed solution into a reaction kettle, sealing and heating the mixed solution, naturally cooling the mixed solution to room temperature after the reaction is finished, separating solids from the mixture by centrifugation, washing a sample with DMF and ethanol, and drying the sample in vacuum to obtain a powder sample of SnO 2 /MOF-5.
3. 3. The method according to claim 2, wherein the molar ratio of stannous chloride dihydrate to zinc nitrate hexahydrate is 1:3-9, the molar ratio of zinc nitrate hexahydrate to terephthalic acid is 3:1, and the molar ratio of zinc nitrate hexahydrate to triethylamine is 0.72:1, wherein the concentration of zinc nitrate hexahydrate in the mixed solution is 0.090M, the concentration of terephthalic acid is 0.030M, and the concentration of triethylamine is 0.125M.
4. 4. The method of claim 3, wherein the molar ratio of stannous chloride dihydrate to zinc nitrate hexahydrate is 1:6.
5. 5. The method according to claim 2, wherein the sealing heating temperature is 80-150 ℃ and the heating time is 12-24 hours.
6. 6. The method according to claim 2, wherein the vacuum drying is performed at a temperature of 40-100 ℃ for a drying time of 6-24 hours.
7. 7. The use of SnO 2 /MOF-5 composite negative electrode material according to claim 1 in aqueous zinc ion batteries.
8. 8. The method according to claim 7, wherein the step of mixing SnO 2 /MOF-5 composite negative electrode material with PVDF in proportion, grinding thoroughly, adding NMP, stirring to form a suspension, uniformly coating the suspension on the surface of a clean zinc sheet by a scraper, drying, and slicing after the solvent evaporates.
9. 9. The application of the composite anode material according to claim 8, wherein the mass ratio of the SnO 2 /MOF-5 to the PVDF is (7-9): 3-1, the concentration of the SnO 2 /MOF-5 composite anode material in NMP is 0.650-0.750 g/mL, the stirring time after adding NMP is 6 h, and the drying condition is that the vacuum drying is carried out for 6-24 hours under the condition of 50-100 ℃.
10. 10. The use according to claim 9, wherein the mass ratio SnO 2 /MOF-5 to PVDF is 9:1.

Description

Preparation method and application of SnO 2/MOF-5 composite anode material Technical Field The invention relates to a preparation method and application of an electrode material, in particular to a preparation method and application of an MOF-5/SnO 2 composite electrode material Background Rechargeable batteries are a key place in global energy systems. The zinc resource is abundant, the cost is lower, and the water-based zinc ion battery adopts the water solution as the electrolyte, so that the safety is obviously higher than that of a lithium ion battery using the organic electrolyte. In addition, zinc metal anodes have a relatively high theoretical capacity (820 mAh g -1) and a relatively low redox potential (-0.76V vs. SHE), and therefore aqueous zinc ion batteries are receiving widespread academia. Although aqueous zinc ion batteries exhibit good application prospects, their performance and cycle life are still limited by several problems. The cathode mainly has the following problems that firstly zinc ions are unevenly deposited on the surface of the cathode in the circulating process, zinc dendrite growth is easy to be initiated, and a diaphragm is likely to be pierced to cause short circuit of a battery, secondly, a common zinc sheet cathode is poor in stability in aqueous electrolyte, hydrogen evolution reaction is easy to occur in the circulating process and is accompanied with corrosion and passivation phenomena, and in addition, continuous side reaction and irreversible deformation of an electrode structure in the zinc depositing/dissolving process further aggravate the attenuation of the battery performance. Disclosure of Invention The invention aims to overcome the defects in the prior art, and aims to provide a SnO 2/MOF-5 composite negative electrode material with high zinc affinity, and another aim of the invention is to provide a preparation method of a SnO 2/MOF-5@Zn water-based zinc ion negative electrode. The SnO 2/MOF-5 composite anode material comprises a metal organic framework material MOF-5 and a zinc-philic metal oxide SnO 2,SnO2 which are uniformly attached to the surface of the MOF-5. The preparation method of the SnO 2/MOF-5 composite anode material adopts a solvothermal one-pot method and comprises the following steps: And adding zinc nitrate hexahydrate into a reaction bottle, stirring and dissolving the zinc nitrate hexahydrate, sequentially adding terephthalic acid, triethylamine and stannous chloride dihydrate into the solution, stirring and dissolving the solution, transferring the mixed solution into a reaction kettle, sealing and heating the mixed solution, naturally cooling the mixed solution to room temperature after the reaction is finished, separating solids from the mixture by centrifugation, washing a sample with DMF and ethanol, and drying the sample in vacuum to obtain a powder sample of SnO 2/MOF-5. The molar ratio of stannous chloride dihydrate to zinc nitrate hexahydrate is 1:3-9, the molar ratio of zinc nitrate hexahydrate to terephthalic acid is 3:1, the molar ratio of zinc nitrate hexahydrate to triethylamine is 0.72:1, wherein the concentration of zinc nitrate hexahydrate in the mixed solution is 0.090M, the concentration of terephthalic acid is 0.030M, and the concentration of triethylamine is 0.125M. Preferably, the molar ratio of stannous chloride dihydrate to zinc nitrate hexahydrate is 1:6. The temperature of the sealing heating is 80-150 ℃ and the heating time is 12-24 hours. The temperature of the vacuum drying is 40-100 ℃, and the drying time is 6-24 hours. The SnO 2/MOF-5 composite anode material is applied to a water-based zinc ion battery. Mixing SnO 2/MOF-5 with PVDF according to a certain proportion, fully grinding, adding NMP, stirring to form a suspension, uniformly coating the suspension on the surface of a clean zinc sheet by a scraper, drying, and slicing after the solvent is evaporated. Further, the mass ratio of SnO 2/MOF-5 to PVDF is (7-9): 3-1, and preferably, the mass ratio of SnO 2/MOF-5 to PVDF is 9:1. The concentration of the SnO 2/MOF-5 composite anode material in NMP is 0.650-0.750 g/mL. Further, the stirring time after adding NMP was 6 h; and the drying condition is that the vacuum drying is carried out for 6-24 hours at the temperature of 50-100 ℃. The beneficial effects of the invention are as follows: SnO 2 is used as a preferential nucleation site to guide Zn 2+ to be uniformly deposited by virtue of high zinc affinity and ionic conductivity, and MOF-5 is used as an ion sieve and a physical barrier to promote Zn 2+ to transmit and limit water molecules to pass through by utilizing regular pore channels, so that side reactions are cooperatively inhibited. The synthesized SnO 2/MOF-5 material exhibited the best overall performance when the molar ratio of stannous chloride dihydrate to zinc nitrate hexahydrate was 1:6, with the coating achieving the best balance between interfacial ionic conductivity and side reaction inhibit