Preparation method of covalent triazine framework material constructed by metal disulfide alkene complex and all-solid-state battery application of covalent triazine framework material

Abstract

The invention discloses a preparation method of a covalent triazine framework material constructed by a metal disulfide alkene complex and an all-solid-state battery application of the covalent triazine framework material. A monomer M1 and a monomer M2 are subjected to a reaction to obtain the metal-based covalent triazine framework material, M1 is bis [1, 2-bis (4-formylbenzene) vinyl-1, 2-dithioene] M (M is one of metal nickel, cobalt, zinc and copper), and M2 is 2, 4, 6-tri (4-aminophenyl)-1, 3, 5-triazine. The obtained metal-based covalent triazine framework material is used as an artificial solid electrolyte interface layer for protecting a sulfide all-solid-state lithium metal negative electrode, so that side reaction between the lithium metal negative electrode and a solid electrolyte can be effectively inhibited, growth of lithium dendrites can be inhibited, uniform deposition of Li < + > can be induced, and the service life of the lithium metal negative electrode is prolonged. Therefore, the high-performance all-solid-state lithium metal battery is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of all-solid-state lithium batteries, and relates to a preparation method of a covalent triazine framework material constructed by a metal dithiolene complex and its application in all-solid-state batteries; more specifically, it relates to a preparation method of a covalent triazine framework material constructed with a metal dithiolene complex as a basic unit and its application in protecting the lithium metal anode in all-solid-state batteries. Background Art

[0002] Traditional lithium-ion batteries have approached the energy density limit (≈300 Wh kg -1 ) and it is difficult to meet the growing demand for battery performance. Moreover, organic electrolytes have significant safety hazards. Especially in electric vehicles, range anxiety and safety issues have discouraged many people. Replacing organic electrolytes with stable solid electrolytes can fundamentally solve the drawback of battery flammability. In all-solid-state batteries, the lithium metal anode has a high theoretical specific capacity (3860 mAh / g), about 10 times that of graphite, and lithium metal has an extremely low reduction potential (-3.04 V vs SHE), so it is considered an ideal anode material. Therefore, all-solid-state lithium metal batteries have attracted much attention due to their high energy density.

[0003] Currently, sulfide electrolytes have been widely studied due to their ultra-high ionic conductivity. However, the lithium metal anode has high reactivity and is prone to react with sulfide electrolytes, generating an ion-electron conductive phase at the interface. This uncontrollable side reaction leads to continuous decomposition of sulfides, promotes the formation of lithium dendrites, and causes rapid performance decay of all-solid-state batteries. Constructing a stable SEI layer on the surface of the lithium metal anode is considered to be one of the effective strategies to improve the lithium metal interface performance.

[0004] CN 119019628A discloses an artificial SEI material, a lithium metal battery anode, a battery and its preparation method; using the prepared CTF material as an artificial SEI layer for the anode of a liquid lithium metal battery can effectively reduce the side reactions at the lithium metal interface, achieve a stable lithium metal deposition / stripping process, promote uniform deposition of lithium and inhibit the formation of lithium dendrites, and improve the cycle stability of liquid lithium metal batteries. However, if it is used in a sulfide all-solid-state lithium metal battery, this CTF material will cause a large impedance at the interface, thereby affecting the cycle performance. Summary of the Invention

[0005] In view of this, the content of the present invention is directed to the problem that in existing sulfide all-solid-state lithium metal batteries, side reactions easily occur between lithium metal and the electrolyte, resulting in poor cycling performance and low Coulombic efficiency. A preparation method of a covalent triazine framework material constructed by a metal dithienyl complex and its application in an all-solid-state battery are provided. The present invention is designed to use a metal dithienyl complex to construct a CTF material with a metal center. This material has a certain conductivity. When it is used as an interfacial protective layer between lithium metal and a sulfide electrolyte in a sulfide all-solid-state lithium metal battery, it can uniform the lithium flux, inhibit the occurrence of interfacial side reactions and the growth of lithium dendrites, thereby obtaining an all-solid-state lithium metal battery with improved cycling performance and Coulombic efficiency.

[0006] The object of the present invention is achieved through the following technical solutions:

[0007] The first aspect of the present invention provides a preparation method of a covalent triazine framework M-CTF material constructed by a metal dithienyl complex. The method includes the following steps:

[0008] S1. In the presence of a solvent, monomer M1 and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine monomer M2 are mixed; monomer M1 is bis[1,2-bis(4-formylphenyl)vinylidene-1,2-dithiolene]M, where M is one of nickel, cobalt, zinc, and copper;

[0009] S2. After the mixed solution is successively subjected to freezing, degassing, and thawing treatments, it is heated under vacuum for reaction;

[0010] S3. The precipitate is collected by centrifugation, and the M-CTF material is obtained through washing, Soxhlet extraction, and drying.

[0011] As an embodiment of the present invention, in step S1, the molar ratio of monomer M1 to monomer M2 is 1:(1 - 5).

[0012] As an embodiment of the present invention, in step S1, the solvent contains 1,2-dichlorobenzene, n-butanol, and glacial acetic acid solution.

[0013] As an embodiment of the present invention, the volume ratio of 1,2-dichlorobenzene to n-butanol in the solvent is (1 - 10):1.

[0014] As an embodiment of the present invention, the molar ratio of glacial acetic acid to n-butanol in the solvent is 1:(1 - 10).

[0015] As an embodiment of the present invention, the concentration of the glacial acetic acid solution in the solvent is 2 - 12M.

[0016] As an embodiment of the present invention, in step S1, the mixing further includes an ultrasonic dispersion process; the ultrasonic frequency is 55 - 65 kHz, and the dispersion time is 3 - 10 minutes.

[0017] As an embodiment of the present invention, in step S2, the temperature of the freezing is -50°C to -70°C.

[0018] As an embodiment of the present invention, in step S2, the degassing is carried out by vacuum pumping.

[0019] As an embodiment of the present invention, in step S2, the temperature of the vacuum heating reaction is 120 - 150°C, and the time is 24 - 96 h.

[0020] As an embodiment of the present invention, in step S3, the solvents used for washing are deionized water, alcohol solvents, and tetrahydrofuran.

[0021] As an embodiment of the present invention, in step S3, the drying is carried out by drying in a vacuum at 110 - 130°C for 18 - 30 h.

[0022] In some specific implementation examples of the present invention, a preparation method of a covalent triazine framework M-CTF material constructed by a metal dithiolene complex is provided. The method includes the following steps:

[0023] 1) Add monomer M1 and monomer M2 into a 10 mL heat-resistant glass container, which contains a 1,2-dichlorobenzene, n-butanol, and glacial acetic acid solution with a certain volume ratio. Ultrasonically treat the mixed solution for five minutes.

[0024] 2) Subject the ultrasonically treated solution in step 1) to three freeze-degassing-thawing treatments and vacuum seal it. Heat it at a certain temperature for three days. Cool the product to room temperature. Centrifuge the precipitate, and obtain the M-CTF material after washing, Soxhlet extraction, and drying. Further, monomer M1 and monomer M2 are mixed with a solvent and ultrasonically dispersed, and the dispersed solution is obtained as the M-CTF material after freezing treatment, vacuum sealing, centrifugal collection, washing, and drying.

[0025] In the second aspect, the present invention provides a negative electrode for an all-solid-state lithium metal battery, including lithium metal and a negative electrode slurry loaded with the M-CTF material prepared by the aforementioned method.

[0026] As an embodiment of the present invention, the negative electrode slurry is composed of an M-CTF material, a binder, and a solvent.

[0027] As an embodiment of the present invention, the binder used in the negative electrode slurry is one of styrene-butadiene rubber, carboxymethyl cellulose, polybutene rubber, and polyvinylidene fluoride.

[0028] As an embodiment of the present invention, the solvent used in the negative electrode slurry is one of xylene, o-xylene, p-xylene, n-hexane, and mesitylene.

[0029] As an embodiment of the present invention, the negative electrode slurry is composed of an M-CTF material, a binder, and a solvent mixed in a mass ratio of 100:(1 - 10):(100 - 3000).

[0030] As an embodiment of the present invention, the negative electrode slurry is coated on the surface of lithium metal and then vacuum dried. Further, the coating method of the slurry on the lithium metal negative electrode is doctor blading.

[0031] In a third aspect, the present invention provides a all-solid-state lithium metal battery, the negative electrode of which is the negative electrode for all-solid-state lithium metal battery described above; the all-solid-state lithium metal battery uses a sulfide electrolyte.

[0032] As an embodiment of the present invention, the positive electrode active material included in the positive electrode of the all-solid-state lithium metal battery is one of lithium iron phosphate, lithium cobaltate, lithium nickel cobalt manganate, lithium manganese phosphate, lithium titanate, lithium nickelate, and lithium manganate.

[0033] As an embodiment of the present invention, the electrolyte used in the all-solid-state lithium metal battery is at least one of Li3PS4, Li 10 GeP2S 12 , Li6PS5Cl, Li6PS5Br, and Li6PS5I.

[0034] In the present invention, monomer M1 and monomer M2 react to obtain a CTF material constructed by a metal dithiolene complex; this CTF material can be used as an artificial SEI layer to reduce the side reaction at the interface between lithium metal and sulfide in a sulfide all-solid-state battery; thereby obtaining an all-solid-state lithium metal battery with improved cycling performance and Coulomb efficiency. Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1) The metal-bis(dithiolene) complex has rich electrochemical activity and can be used for the construction of conductive and electroactive MOFs. When used as a protective layer for lithium metal, it can accelerate electron transfer, adjust the electronic structure, reduce the local current density, and achieve more uniform lithium deposition, thereby inhibiting the formation of lithium dendrites.

[0036] 2) The C=N bond has a strong attracting ability to Li + , increasing the lithiumophilic sites of the framework material and significantly improving the ionic conductivity and lithium ion transference number of the material.

[0037] 3) The M-CTF material has excellent electrochemical stability, can increase the critical current density, and further promote uniform lithium deposition and inhibit the formation of lithium dendrites. Brief Description of the Drawings

[0038] The present invention will be further described by way of schematic examples in conjunction with the accompanying drawings, making the objectives, features and advantages of the present invention more apparent, and not constituting an undue limitation to the present invention.

[0039] Figure 1 Synthesis route and structural schematic diagram of the M-CTF material provided in Example 1 of the present invention.

[0040] Figure 2 XRD pattern of the product of Example 1 of the present invention;

[0041] Figure 3 Comparison chart of the cycling performance of the all-solid-state lithium metal battery between Example 1 of the present invention and the control group. Detailed Description of the Invention

[0042] The present invention will be described in detail below in conjunction with the embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several adjustments and improvements can still be made. These all fall within the protection scope of the present invention.

[0043] Among the monomers involved in the examples, bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]cobalt was synthesized exactly according to the literature (J. Am. Chem. Soc. 2022, 144, 8267 - 8277). The synthesis steps include: (1) 1,3-dithiol-2-thione (1.34 g, 10.0 mmol) was dissolved in anhydrous tetrahydrofuran (20 mL). At -78 °C, TMPMgCl·LiCl (9.91 mL, 11.0 mmol, 1.11 M in THF) was slowly added dropwise, and the mixture was stirred for 0.5 h. At -78 °C, ZnCl2 solution (12.0 mL, 12.0 mmol, 1.0 M in THF) was added, and the mixture was stirred for 15 min. The newly prepared zinc reagent was added to an anhydrous NMP (10 mL) solution of 2-(4-iodophenyl)-5,5-dimethyl-1,3-dioxane (2.55 g, 8.0 mmol) and Pd(PPh3)4 (1.15 g, 1.0 mmol) at 25 °C. The mixture was stirred at 25 °C for 24 h, then quenched with saturated aqueous ammonium chloride solution (50 mL) and extracted with ethyl acetate (3 × 100 mL). The combined extracts were dried over Na2SO4. After filtration, it was evaporated in vacuo. The crude product was purified by flash column chromatography (isohexane / dichloromethane (1:2); silica gel, 200 - 300 mesh) to obtain Compound 1. (2) Compound 1 (0.81 g, 2.5 mmol) was dissolved in tetrahydrofuran (20 mL). At -78 °C, TMPMgCl·LiCl (2.48 mL, 4.4 mmol, 1.11 M in THF) was slowly added dropwise, and the mixture was stirred for 0.5 h. At -78 °C, ZnCl2 solution (4.8 mL, 4.8 mmol, 1.0 M in THF) was added, and the mixture was stirred for 15 minutes. The newly prepared zinc reagent was added to an anhydrous NMP (10 mL) solution of 2-(4-iodophenyl)-5,5-dimethyl-1,3-dioxane (1.0 g, 3.2 mmol) and Pd(PPh3)4 (0.29 g, 0.25 mmol) at 25 °C. The mixture was stirred at 25 °C for 24 hours, then quenched with saturated aqueous ammonium chloride solution (50 mL) and extracted with ethyl acetate (3 × 100 mL). The combined extracts were dried over Na2SO4. After filtration, it was evaporated in vacuo. The crude product was purified by flash column chromatography (isohexane / dichloromethane (1:2); silica gel, 200 - 300 mesh) to obtain Compound 2. (3) Hg(OAc)2 (1.91 g, 6.0 mmol) was added in portions to a solution of Compound 2 (1.02 g, 2.0 mmol) in chloroform (40 mL) and acetic acid (12.5 mL) at 25 °C. The mixture was stirred at this temperature for 6 h, then the precipitate was filtered through diatomaceous earth. The resulting solution was washed with saturated aqueous sodium carbonate solution (2 × 100 mL) and water (2 × 100 mL).The organic layer was dried with Na2SO4, filtered, and the solvent was evaporated under vacuum. The crude product was purified by flash column chromatography (dichloromethane; silica gel, 200 - 300 mesh) to obtain Compound 3. (4) Compound 3 (1.99 g, 4 mmol) was added to a sodium methoxide solution (432 mg, 8 mmol, 20 mL). After stirring for 45 minutes, CoCl2·6H2O (1.92 g, 8 mmol) was added. Two hours later, tetrabutylammonium iodide (1.48 g, 4 mmol) was added. After the reaction was completed, methanol was evaporated, and the residue was diluted with dichloromethane. Excess iodine was added to the above dichloromethane solution. The mixture was stirred for 15 minutes and then filtered. The solvent was evaporated under vacuum. The crude product was purified by flash column chromatography (dichloromethane; silica gel, 200 - 300 mesh) to obtain Compound 4. (5) Compound 4 (400 mg, 0.4 mmol) was dissolved in chloroform (30 mL), and trifluoroacetic acid (10 mL) was added. The green solution was stirred at room temperature for 24 h under an argon atmosphere. The reaction progress was monitored by thin-layer chromatography (TLC). After the reaction was completed, the reaction mixture was diluted with dichloromethane (50 mL) and water (50 mL). The organic layer was separated and washed with saturated aqueous sodium bicarbonate solution (3 × 30 mL) and water. After the organic layer was separated, it was dried with anhydrous sodium sulfate and evaporated under vacuum. The residue was purified by column chromatography (dichloromethane; silica gel, 200 - 300 mesh) to obtain bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]cobalt.

[0044] Replacing CoCl2·6H2O in the above step (4) with NiCl2·6H2O can obtain bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]nickel.

[0045] Replacing CoCl2·6H2O in the above step (4) with ZnCl2 can obtain bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]zinc.

[0046] Replacing CoCl2·6H2O in the above step (4) with CuCl2·2H2O can obtain bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]copper.

[0047] Example 1

[0048] This example demonstrates a synthetic scheme for a CTF material constructed from a metal dithiolene complex. The Co-CTF material is synthesized from monomer M1 bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]cobalt and monomer M2 2,4,6-tris(4-aminophenyl)-1,3,5-triazine; specifically:

[0049] Place 1,2-dichlorobenzene, n-butanol, and 6M glacial acetic acid solution (2 mL: 1.2 mL: 0.4 mL) in a 10 mL heat-resistant glass tube. Add bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]cobalt (13.1 mg, 0.02 mmol) and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (10.6 mg, 0.03 mmol) to the above solution. After sonication at 60 kHz at room temperature for 5 minutes, perform three freeze-degassing-thawing treatments (freezing temperature -60 °C, degassing by vacuum pumping) and vacuum treat at 120 °C for 72 h. The precipitate is collected by centrifugation and washed several times with deionized water, methanol, and tetrahydrofuran, and then dried overnight at 120 °C under vacuum to obtain the product. The specific reaction process and structure are as Figure 1 shown in the schematic diagram, and the XRD of the obtained product is as Figure 2 shown, which proves the purity of the synthesized Co-CTF sample.

[0050] Example 2

[0051] This example demonstrates a synthesis scheme of a CTF material constructed from a metal dithiolene complex. The Ni-CTF material is synthesized from monomer M1 bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]nickel and monomer M2 2,4,6-tris(4-aminophenyl)-1,3,5-triazine. Specifically:

[0052] Place 1,2-dichlorobenzene, n-butanol, and 6M glacial acetic acid solution (2 mL: 1.2 mL: 0.4 mL) in a 10 mL heat-resistant glass tube. Add bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]nickel (13.1 mg, 0.02 mmol) and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (10.6 mg, 0.03 mmol) to the above solution. After sonication at 60 kHz at room temperature for 5 minutes, perform three freeze-degassing-thawing treatments (freezing temperature -60 °C, degassing by vacuum pumping) and vacuum treat at 120 °C for 72 h. The precipitate is collected by centrifugation and washed several times with deionized water, methanol, and tetrahydrofuran, and then dried overnight at 120 °C under vacuum to obtain the product.

[0053] Example 3

[0054] This example demonstrates a synthesis scheme of a CTF material constructed from a metal dithiolene complex. The Zn-CTF material is synthesized from monomer M1 bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]zinc and monomer M2 2,4,6-tris(4-aminophenyl)-1,3,5-triazine. Specifically:

[0055] In a 10 mL heat-resistant glass tube, 1,2-dichlorobenzene, n-butanol and 6 M glacial acetic acid solution (2 mL: 1.2 mL: 0.4 mL) were placed, and bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]zinc (13.2 mg, 0.02 mmol) and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (10.6 mg, 0.03 mmol) were added to the above solution. After ultrasonic treatment at 60 kHz at room temperature for 5 minutes, it was subjected to three freeze-degassing-thawing treatments (freezing temperature -60 °C, degassing by vacuum) and vacuum treatment at 120 °C for 72 h. The precipitate was collected by centrifugation and washed several times with deionized water, methanol, and tetrahydrofuran, and then dried overnight at 120 °C under vacuum to obtain the product.

[0056] Example 4

[0057] This example demonstrates a synthesis scheme for a CTF material constructed from a metal dithiolene complex. The Co-CTF material is synthesized from monomer M1 bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]cobalt and monomer M2 2,4,6-tris(4-aminophenyl)-1,3,5-triazine. Specifically:

[0058] In a 10 mL heat-resistant glass tube, 1,2-dichlorobenzene, n-butanol and 6 M glacial acetic acid solution (2 mL: 1.2 mL: 0.4 mL) were placed, and bis[1,2-bis(4-formylphenyl)vinyl-1,2-dithiolene]cobalt (13.1 mg, 0.02 mmol) and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (21.2 mg, 0.06 mmol) were added to the above solution. After ultrasonic treatment at 60 kHz at room temperature for 5 minutes, it was subjected to three freeze-degassing-thawing treatments (freezing temperature, degassing by vacuum) and vacuum treatment at 120 °C for 72 h. The precipitate was collected by centrifugation and washed several times with deionized water, methanol, and tetrahydrofuran, and then dried overnight at 120 °C under vacuum to obtain the product.

[0059] Performance test example

[0060] The Co-CTF of Example 1 was used as a lithium metal protective layer in a all-solid-state lithium metal battery. The specific method is as follows:

[0061] The positive electrode material is a powder obtained by ball-milling and mixing lithium borate-coated NCM811 (LBO@NCM811), electrolyte Li6PS5Cl (LPSC), and carbon nanofibers in a mass ratio of 70:29:1. The electrolyte LPSC is obtained by heat-treating a certain molar ratio of Li2S, P2S5, and LiCl at 550 °C for 4 h. Co-CTF, BR binder, and p-xylene are stirred evenly in a mass ratio of 100:3:1000, and then coated on the lithium surface by doctor blading, with a coating amount of 0.5 mg cm -2 , to obtain Co-COF@Li, which is dried in a vacuum oven at 60 °C for 12 h, and then punched into 10 mm for standby after drying. It is assembled into a sulfide all-solid-state battery in a mold for testing. First, the electrolyte LPSC is pressed in the mold at 270 MPa, and then, 10 mg of the positive electrode material is added on one side of the electrolyte and pressed at 630 MPa, with aluminum foil as the positive electrode current collector. A Co-COF@Li sheet is attached to the other side of the electrolyte, and copper foil is added as the current collector to obtain the LBO@NCM811 / Li6PS5Cl-Co-COF / Li full cell.

[0062] The control group assembled the all-solid-state lithium metal battery in the same way. Different from Example 1, the control group did not add the Co-COF material as the protective layer of the lithium metal. At the same time, the CTF material synthesized in Example 1 of the patent (CN119019628A) was used as the protective layer of the lithium metal, and CTF@Li was prepared as a comparative sample under the same conditions.

[0063] The assembled batteries were subjected to long-cycle charge-discharge tests at 0.5C. The results are as Figure 3 shown. The initial charge specific capacity of the all-solid-state battery with the Co-COF material provided in Example 1 as the protective layer of the lithium metal reached 184.2 mAh / g, the initial discharge specific capacity reached 154.7 mAh / g, the initial Coulomb efficiency was 84.0%, and after 200 cycles, the capacity retention rate was 58.0%. On the contrary, for the lithium metal battery without the Co-CTF material provided in Example 1 as the protective layer of the lithium metal, after 200 cycles under the same conditions, the capacity decayed to 39.1%. And the capacity of the CTF-protected lithium metal all-solid-state battery in the comparative sample decayed rapidly.

[0064] In summary, the present invention discloses a preparation method of a CTF material constructed by a metal dithiolene complex. When the M-CTF material is used as a lithium-protective artificial SEI layer in a sulfide all-solid-state lithium metal battery, it can effectively reduce the side reactions between lithium metal and the electrolyte, achieve more uniform lithium deposition, inhibit the formation of lithium dendrites, thereby greatly improving the initial Coulomb efficiency of the all-solid-state lithium metal battery and improving the stability performance during the battery cycle. It can be foreseen that this CTF material with a metal center has good application prospects in a battery system with lithium metal as the negative electrode.

[0065] The specific embodiments of the present invention have been described above. It should be noted that the above embodiments are not exhaustive, and those skilled in the art can make modifications and changes within the scope of the claims, which does not affect the essence of the present invention.

Claims

1. A preparation method of a covalent triazine framework M-CTF material constructed from a metal dithiolene complex, characterized in that, The method includes the following steps: S1. In the presence of a solvent, monomer M1 and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine monomer M2 are mixed; monomer M1 is bis[1,2-bis(4-formylphenyl)vinylidene-1,2-dithiolene]M, where M is one of nickel, cobalt, zinc, and copper; S2. After the mixed solution is successively subjected to freezing, degassing, and thawing treatments, it is heated under vacuum for reaction; S3. The precipitate is collected by centrifugation, and after washing, Soxhlet extraction, and drying, the M-CTF material is obtained.

2. The preparation method according to claim 1, characterized in that, In step S1, the molar ratio of monomer M1 to monomer M2 is 1:(1 - 5).

3. The preparation method according to claim 1, wherein, In step S1, the solvent contains 1,2-dichlorobenzene, n-butanol, and glacial acetic acid solution; it also includes at least one of the following technical features: A. The volume ratio of 1,2-dichlorobenzene to n-butanol is (1 - 10):1; B. The molar ratio of glacial acetic acid to n-butanol is 1:(1 - 10); C. The concentration of the glacial acetic acid solution is 2 - 12M.

4. The preparation method according to claim 1, characterized in that In step S1, the mixing also includes an ultrasonic dispersion process; the ultrasonic frequency is 55 - 65 kHz, and the dispersion time is 3 - 10 minutes.

5. The preparation method according to claim 1, characterized in that, In step S2, it also includes at least one of the following technical features: A. The temperature of the freezing is -50°C to -70°C; B. The degassing is carried out by vacuum pumping; C. The temperature of the vacuum heating reaction is 120 - 150°C, and the time is 24 - 96h.

6. The preparation method according to claim 1, wherein, In step S3, it also includes at least one of the following technical features: A. The solvent used for the washing is deionized water, an alcohol solvent, and tetrahydrofuran; B. The drying is drying at 110 - 130°C under vacuum for 18 - 30h.

7. An anode for an all-solid-state lithium metal battery, characterized in that, It includes a lithium metal and a negative electrode slurry loaded with the M-CTF material prepared by the method as described in claim 1 on it.

8. The negative electrode for an all-solid-state lithium metal battery according to claim 7, characterized in that, The negative electrode slurry includes at least one of the following technical features: A. It is composed of a mixture of M-CTF material, a binder, and a solvent; B. The binder used in the negative electrode slurry is one of styrene-butadiene rubber, carboxymethyl cellulose, polybutene rubber, and polyvinylidene fluoride; C. The solvent used in the negative electrode slurry is one of xylene, o-xylene, p-xylene, n-hexane, and mesitylene; D. It is composed of a mixture of M-CTF material, a binder, and a solvent with a mass ratio of 100:(1 - 10):(100 - 3000); E. The negative electrode slurry is coated on the surface of the lithium metal and dried under vacuum.

9. A all-solid-state lithium metal battery, characterized in that, Its negative electrode is the negative electrode for all-solid-state lithium metal batteries as described in claim 7; the all-solid-state lithium metal battery uses a sulfide electrolyte, and the sulfide electrolyte is at least one of Li3PS4, Li 10 GeP2S 12 , Li6PS5Cl, Li6PS5Br, Li6PS5I.

10. The all-solid-state lithium metal battery according to claim 9, wherein, The positive electrode of the all-solid-state lithium metal battery includes a positive electrode active material which is one of lithium iron phosphate, lithium cobaltate, lithium nickel cobalt manganate, lithium manganese phosphate, lithium titanate, lithium nickelate, and lithium manganate.

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