Preparation method of polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material

Abstract

The invention discloses a preparation method of a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material, which belongs to the technical field of inorganic material preparation. The method comprises the following steps: titanium foil and a NaOH aqueous solution are subjected to a solvent thermal reaction A to obtain product A, and product A is cleaned and dried to obtain sodium titanate; water and ethanol are mixed to obtain a mixed solution, ammonia is added to the mixed solution to obtain an ammonia mixed solution, formaldehyde aqueous solution and a polyphenol aqueous solution are added to the ammonia mixed solution and stirred to obtain a mixed solution; a metal salt solution is added to the mixed solution and mixed to obtain a mixed metal salt solution; sodium titanate and the mixed metal salt solution are stirred and then subjected to a solvent thermal reaction B to obtain product B, and product B is cleaned and dried to obtain a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material.

Description

Technical Field

[0001] The invention belongs to the technical field of inorganic material preparation, and particularly relates to a method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material. Background Art

[0002] With the booming development of mobile electronics, new energy vehicles, and energy storage systems, lithium-ion batteries have enormous market value and broad application prospects. However, lithium resources are limited. In recent years, with the development of electric vehicles, the cost of lithium resources has increased significantly, which is not conducive to its application in large-scale energy storage systems. Sodium resources are abundant and cheap, and the physicochemical properties of sodium are similar to those of lithium. Therefore, sodium-ion batteries are a very promising energy storage device. Therefore, the development and preparation of anode materials with high rate performance and excellent cycle life has become a primary research goal.

[0003] Layered titanates are gaining increasing attention as anode materials for sodium-ion batteries due to their advantages, such as low operating voltage and ease of preparation. However, the narrow interlayer spacing of layered titanates results in slow sodium ion diffusion, resulting in low capacity and rapid decay during insertion and extraction. Furthermore, the irreversible insertion and extraction of sodium ions between the layers causes lattice distortion, impairing structural stability during charge and discharge.

[0004] Meanwhile, surface coating engineering has been shown to be a successful solution to improve the structural stability of titanates during Na-ion storage.

[0005] Therefore, there is an urgent need for a method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material to solve the problems of low capacity, low sodium ion diffusion rate and poor cycle stability during charge and discharge of existing layered titanates. Summary of the Invention

[0006] The purpose of the present invention is to overcome the problems of low capacity, low sodium ion diffusion rate and poor cycle stability of existing layered titanates during charge and discharge, and proposes a preparation method of a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material comprises the following steps:

[0009] The titanium foil and the NaOH aqueous solution undergo a solvothermal reaction A to obtain a product A, and the product A is washed and dried to obtain sodium titanate;

[0010] Mixing water and ethanol to obtain a mixed solution, adding ammonia water to the mixed solution to obtain an ammonia mixed solution, adding formaldehyde aqueous solution and polyphenol aqueous solution to the ammonia mixed solution and stirring to obtain a mixed solution; adding a metal salt solution to the mixed solution and mixing to obtain a mixed metal salt solution;

[0011] Sodium titanate and a mixed metal salt solution are stirred and then subjected to solvent thermal reaction B to obtain product B, and the product B is washed and dried to obtain a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material.

[0012] Furthermore, the concentration of the NaOH aqueous solution is 0.3-1 mol / L, the solvent thermal reaction A is carried out at 140-220°C for 18-24 hours, and the sodium titanate is Na2Ti2O5, Na2Ti3O7 or Na2Ti6O 13 One of them.

[0013] Furthermore, the polyphenols in the polyphenol aqueous solution are one or a combination of tannic acid, gallic acid, cholinesterase, dopamine, etc., and the mass concentration of the polyphenol aqueous solution is 0.01 to 0.04 mol / L.

[0014] Furthermore, the mass fraction of the ammonia water is 25%, and the volume ratio of water to ethanol in the mixed solution is (1-4):1.

[0015] Furthermore, the volume of ammonia solution in the mixed solution obtained by adding the formaldehyde aqueous solution and the polyphenol aqueous solution to the ammonia aqueous solution and stirring is: the volume of the formaldehyde aqueous solution: the volume of the polyphenol aqueous solution = 1: (5-10): (10-20), and the mass fraction of the formaldehyde aqueous solution is 37%; and the stirring time for the mixed solution obtained by adding the formaldehyde aqueous solution and the polyphenol aqueous solution to the ammonia aqueous solution and stirring is 24 hours.

[0016] Furthermore, the metal salt is one of bismuth chloride, tin chloride or antimony chloride, and the concentration of the metal salt is 0.1 to 0.5 mol / L.

[0017] Furthermore, the volume of the metal salt solution in the mixed metal salt solution obtained after adding the metal salt solution to the mixed solution and mixing: the volume of the polyphenol aqueous solution = 1: (10-20), the stirring time for the mixed metal salt solution obtained after adding the metal salt solution to the mixed solution and mixing is 12 hours, and the conditions of the solvent thermal reaction B are 24 hours at 100°C.

[0018] Furthermore, the solvothermal reaction A and the solvothermal reaction B are both carried out in a reactor.

[0019] A polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material is prepared by the above-mentioned preparation method.

[0020] A sodium ion battery, wherein the negative electrode material is the above-mentioned polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material.

[0021] Compared with the prior art, the present invention has the following beneficial technical effects:

[0022] The present invention proposes a method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material. The method uses the polyphenol-formaldehyde polymer chelated metal ion as a coating layer and a titanate material as a base to prepare a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material with excellent sodium storage performance. The method can avoid the shortcomings of existing layered titanate materials, such as the narrow interlayer spacing that leads to slow sodium ion diffusion, low capacity, rapid attenuation during insertion / extraction, lattice distortion caused by irreversible insertion and extraction of sodium ions between layers, and poor structural stability during charge and discharge.

[0023] Furthermore, polyphenols and formaldehyde form a 3D cross-linked network structure polymer in an alkaline environment, which is beneficial to the storage of sodium ions and can increase the sodium ion diffusion rate of titanate materials.

[0024] Furthermore, the large amount of phenol groups contained in the polyphenol-formaldehyde polymer can effectively chelate metal ions, which can bring high capacity performance of alloyed metals to titanate materials.

[0025] Furthermore, the coating layer after the polyphenol-formaldehyde polymer chelates the metal ions can be well adsorbed on the surface of the base titanate material to act as a protective layer, avoiding the poor structural stability caused by lattice distortion during the charge and discharge process, thereby improving the cycle stability of the titanate material, so that the final polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material shows good application potential in the field of sodium ion battery negative electrode materials.

[0026] The polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material proposed in the present invention is prepared by the preparation method of the present invention, which can improve the capacity and sodium ion transmission rate, reduce the lattice distortion during the sodium ion insertion and extraction process, and has excellent rate and cycle stability performance, showing good application potential in the field of sodium ion batteries.

[0027] The invention proposes a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material, which has a simple preparation process and excellent sodium storage performance, and is a sodium ion battery negative electrode material with good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings in the specification are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0029] Figure 1 TEM and element mapping diagrams of the tannic acid-formaldehyde polymer chelated bismuth ion surface coating titanate material prepared in Example 1 of the present invention as the negative electrode of the sodium ion battery.

[0030] Figure 2 This is a rate performance diagram of the tannic acid-formaldehyde polymer chelated bismuth ion surface coating titanate material prepared in Example 1 of the present invention as the negative electrode of a sodium ion battery.

[0031] Figure 3 The present invention is a schematic flow chart of a method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material. DETAILED DESCRIPTION

[0032] The present invention is described in further detail below:

[0033] A preparation method of a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material, see Figure 3 , including the following steps:

[0034] 1) Place titanium foil in a reactor containing 0.3-1 mol / L NaOH aqueous solution, and perform solvent thermal reaction at 140-220°C for 18-24 hours, then wash and dry to obtain Na2Ti2O5, Na2Ti3O7, Na2Ti6O 13 A sodium titanate.

[0035] 2) adding 25% by mass of ammonia water to a solution thoroughly mixed with water and ethanol (volume ratio (1-4):1), and then adding 37% by mass of formaldehyde aqueous solution and 0.01-0.04 mol / L of a polyphenol aqueous solution selected from the group consisting of tannic acid, gallic acid, chondric acid, and dopamine, or a combination thereof, in a ratio of ammonia aqueous solution volume: formaldehyde aqueous solution volume: polyphenol aqueous solution volume = 1: (5-10): (10-20), and stirring for 24 hours to obtain a mixed solution.

[0036] 3) adding a metal salt solution of one of bismuth chloride, tin chloride, antimony chloride, etc., with a concentration of 0.1 to 0.5 mol / L, and a ratio of the volume of the metal salt solution to the volume of the polyphenol aqueous solution = 1:(10 to 20), to the mixed solution of step 2), stirring for 12 hours, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), performing a solvothermal reaction at 100° C. for 24 hours, and then washing and drying the mixture to obtain a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material.

[0037] 4) The prepared polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material is directly cut into electrode sheets as the negative electrode, and a sodium ion battery is assembled.

[0038] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0039] The present invention is described in further detail below in conjunction with the embodiments:

[0040] Example 1

[0041] 1) Titanium foil was placed in a reactor containing 1 mol / L NaOH aqueous solution, and subjected to solvothermal reaction at 220°C for 24 h, followed by washing and drying to obtain Na2Ti2O5.

[0042] 2) 0.3 mL of 25% aqueous ammonia was added to a thoroughly mixed solution of water and ethanol (volume ratio 4:1), followed by the addition of 3 mL of 37% aqueous formaldehyde solution and 6 mL of 0.01 mol / L aqueous tannic acid solution, and the mixture was stirred for 24 h to obtain a mixed solution.

[0043] 3) adding 0.6 mL of a 0.1 mol / L bismuth chloride solution to the mixed solution of step 2), stirring for 12 h, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), and subjecting the mixture to a solvent thermal reaction at 100° C. for 24 h. After completion, the mixture was cleaned and dried to obtain a tannic acid-formaldehyde polymer chelated bismuth ion surface coating titanate material.

[0044] 4) The prepared tannic acid-formaldehyde polymer chelated bismuth ion surface-coated titanate material is directly cut into electrode sheets as the negative electrode, and a sodium ion battery is assembled.

[0045] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0046] like Figure 1 This is the TEM and element mapping image of the tannic acid-formaldehyde polymer chelated bismuth ion surface coating titanate material prepared in Example 1. It can be seen from the figure that the prepared material has a nanofiber structure and the surface coating Bi-TAF is clearly visible.

[0047] like Figure 2 This is a rate performance diagram of the tannic acid-formaldehyde polymer chelated bismuth ion surface coating titanate material prepared in Example 1 as a sodium ion battery negative electrode, showing good rate performance.

[0048] Example 2

[0049] 1) Titanium foil was placed in a reactor containing 0.3 mol / L NaOH aqueous solution, and subjected to solvothermal reaction at 180°C for 18 h, followed by washing and drying to obtain Na2Ti3O7.

[0050] 2) Add 0.3 mL of 25% aqueous ammonia to a thoroughly mixed solution of water and ethanol (volume ratio 1:1), then add 3 mL of 37% aqueous formaldehyde solution and 6 mL of 0.01 mol / L aqueous gallic acid solution, and stir for 24 h to obtain a mixed solution.

[0051] 3) adding 0.6 mL of 0.1 mol / L tin chloride solution to the mixed solution of step 2), stirring for 12 h, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), and subjecting the mixture to a solvent thermal reaction at 100° C. for 24 h. After completion, washing and drying, a gallic acid-formaldehyde polymer chelated tin ion surface coating titanate material was obtained.

[0052] 4) The prepared gallic acid-formaldehyde polymer chelated tin ion surface coating titanate material is directly cut into electrode sheets as the negative electrode, and a sodium ion battery is assembled.

[0053] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0054] Example 3

[0055] 1) Titanium foil was placed in a reactor containing 1 mol / L NaOH aqueous solution, and then subjected to solvent thermal reaction at 140°C for 20 h. The resulting solution was then washed and dried to obtain Na2Ti6O 13 .

[0056] 2) Add 0.3 mL of 25% ammonia water to a mixture of water and ethanol (4:1 by volume), then add 3 mL of 37% formaldehyde solution and 6 mL of 0.01 mol / L cholinesterase solution, and stir for 24 h to obtain a mixed solution.

[0057] 3) adding 0.6 mL of 0.5 mol / L antimony chloride solution to the mixed solution of step 2), stirring for 12 h, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), and subjecting the mixture to a solvent thermal reaction at 100° C. for 24 h. After completion, washing and drying, the mixture is obtained to obtain a titanate material having a surface coating of chelated antimony ions with a hydroxybenzoic acid-formaldehyde polymer.

[0058] 4) The prepared hyaluronic acid-formaldehyde polymer chelated antimony ion surface coating titanate material is directly cut into electrode sheets as the negative electrode, and a sodium ion battery is assembled.

[0059] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0060] Example 4

[0061] 1) Titanium foil was placed in a reactor containing 1 mol / L NaOH aqueous solution, and subjected to solvothermal reaction at 220°C for 24 h, followed by washing and drying to obtain Na2Ti2O5.

[0062] 2) 0.3 mL of 25% ammonia water was added to a solution thoroughly mixed with water and ethanol (volume ratio 4:1), followed by the addition of 3 mL of 37% formaldehyde aqueous solution and 6 mL of 0.01 mol / L dopamine aqueous solution, and the mixture was stirred for 24 h to obtain a mixed solution.

[0063] 3) adding 0.3 mL of 0.5 mol / L bismuth chloride solution to the mixed solution of step 2), stirring for 12 h, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), and subjecting the mixture to a solvent thermal reaction at 100° C. for 24 h. After completion, the mixture was cleaned and dried to obtain a dopamine-formaldehyde polymer chelated bismuth ion surface coating titanate material.

[0064] 4) The prepared dopamine-formaldehyde polymer chelated bismuth ion surface-coated titanate material is directly cut into electrode sheets as the negative electrode, and a sodium ion battery is assembled.

[0065] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0066] Example 5

[0067] 1) Titanium foil was placed in a reactor containing 1 mol / L NaOH aqueous solution, and subjected to solvothermal reaction at 220°C for 24 h, followed by washing and drying to obtain Na2Ti2O5.

[0068] 2) 0.3 mL of 25% aqueous ammonia was added to a thoroughly mixed solution of water and ethanol (volume ratio 4:1), followed by the addition of 3 mL of 37% aqueous formaldehyde and 6 mL of a 0.02 mol / L mixed solution of tannic acid and gallic acid (mass ratio of tannic acid to gallic acid 1:1). The mixture was stirred for 24 h to obtain a mixed solution.

[0069] 3) adding 0.3 mL of 0.1 mol / L bismuth chloride solution to the mixed solution of step 2), stirring for 12 h, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), and subjecting the mixture to a solvent thermal reaction at 100° C. for 24 h. After completion, the mixture was cleaned and dried to obtain a tannic acid, gallic acid-formaldehyde polymer chelated bismuth ion surface coating titanate material.

[0070] 4) The prepared tannic acid, gallic acid-formaldehyde polymer chelated bismuth ion surface coating titanate material is directly cut into electrode sheets as the negative electrode, and a sodium ion battery is assembled.

[0071] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0072] Example 6

[0073] 1) Titanium foil was placed in a reactor containing 1 mol / L NaOH aqueous solution, and subjected to solvothermal reaction at 220°C for 24 h, followed by washing and drying to obtain Na2Ti2O5.

[0074] 2) Add 0.6 mL of 25% ammonia water to a thoroughly mixed solution of water and ethanol (volume ratio 4:1), then add 3 mL of 37% formaldehyde aqueous solution and 6 mL of a 0.03 mol / L mixed solution of tannic acid, gallic acid, and hyaluronic acid (mass ratio of tannic acid, gallic acid, and hyaluronic acid is 1:1:1), and stir for 24 h to obtain a mixed solution.

[0075] 3) adding 0.3 mL of 0.1 mol / L bismuth chloride solution to the mixed solution of step 2), stirring for 12 h, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), and subjecting the mixture to a solvent thermal reaction at 100° C. for 24 h. After the reaction, washing and drying were performed to obtain a titanate material with a surface coating of tannic acid, gallic acid, and galactolyl acid-formaldehyde polymer chelated bismuth ions.

[0076] 4) The prepared tannic acid, gallic acid and bismuth ion chelated surface coating titanate materials are directly cut into electrode sheets as negative electrodes, and sodium ion batteries are assembled.

[0077] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0078] Example 7

[0079] 1) Titanium foil was placed in a reactor containing 1 mol / L NaOH aqueous solution, and subjected to solvothermal reaction at 220°C for 24 h, followed by washing and drying to obtain Na2Ti2O5.

[0080] 2) 0.6 mL of 25% ammonia water was added to a thoroughly mixed solution of water and ethanol (volume ratio 4:1), followed by the addition of 3 mL of 37% formaldehyde aqueous solution and 6 mL of a 0.04 mol / L mixed solution of tannic acid, gallic acid, hyaluronic acid, and dopamine (mass ratio of tannic acid, gallic acid, hyaluronic acid, and dopamine being 1:1:1:1). The mixture was stirred for 24 h to obtain a mixed solution.

[0081] 3) adding 0.6 mL of 0.1 mol / L bismuth chloride solution to the mixed solution of step 2), stirring for 12 h, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), and subjecting the mixture to a solvent thermal reaction at 100° C. for 24 h. After the reaction, washing and drying the mixture to obtain a titanate material having a surface coating of tannic acid, gallic acid, choline acid, and dopamine-formaldehyde polymer chelated bismuth ions.

[0082] 4) The prepared tannic acid, gallic acid, choline acid and dopamine-formaldehyde polymer chelated bismuth ion surface coating titanate materials are directly cut into electrode sheets as negative electrodes, and sodium ion batteries are assembled.

[0083] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0084] Example 8

[0085] 1) Titanium foil was placed in a reactor containing 0.5 mol / L NaOH aqueous solution, and subjected to solvothermal reaction at 220°C for 24 h, followed by washing and drying to obtain Na2Ti2O5.

[0086] 2) 0.3 mL of 25% ammonia water was added to a thoroughly mixed solution of water and ethanol (volume ratio 3:1), followed by the addition of 1.8 mL of 37% formaldehyde aqueous solution and 3.6 mL of a 0.04 mol / L mixed solution of tannic acid, gallic acid, hyaluronic acid, and dopamine (mass ratio of tannic acid, gallic acid, hyaluronic acid, and dopamine being 1:1:1:1). The mixture was stirred for 24 h to obtain a mixed solution.

[0087] 3) adding 0.3 mL of 0.2 mol / L bismuth chloride solution to the mixed solution of step 2), stirring for 12 h, and then transferring the mixture to a reactor containing the sodium titanate prepared in step 1), and subjecting the mixture to a solvent thermal reaction at 100° C. for 24 h. After the reaction, washing and drying the mixture to obtain a titanate material having a surface coating of tannic acid, gallic acid, choline acid, and dopamine-formaldehyde polymer chelated bismuth ions.

[0088] 4) The prepared tannic acid, gallic acid, choline acid and dopamine-formaldehyde polymer chelated bismuth ion surface coating titanate materials are directly cut into electrode sheets as negative electrodes, and sodium ion batteries are assembled.

[0089] 5) Conduct electrochemical performance tests on the assembled sodium ion battery.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit its scope of protection. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art may still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the scope of protection of the pending claims of the invention.

Claims

1. A method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material, characterized in that: The steps include: The titanium foil and the NaOH aqueous solution undergo a solvothermal reaction A to obtain a product A, and the product A is washed and dried to obtain sodium titanate; Water and ethanol are mixed to obtain a mixed solution, ammonia water is added to the mixed solution to obtain an ammonia mixed solution, and formaldehyde aqueous solution and polyphenol aqueous solution are added to the ammonia mixed solution and stirred to obtain a mixed solution; the polyphenol in the polyphenol aqueous solution is one or a combination of tannic acid, gallic acid, styryl acid, and dopamine, and the mass concentration of the polyphenol aqueous solution is 0.01-0.04 mol / L; a metal salt solution is added to the mixed solution and mixed to obtain a mixed metal salt solution; the metal salt is one of bismuth chloride, tin chloride, or antimony chloride, and the concentration of the metal salt is 0.1-0.5 mol / L. Sodium titanate and a mixed metal salt solution are stirred and then subjected to solvent thermal reaction B to obtain product B, and the product B is washed and dried to obtain a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material.

2. The method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material according to claim 1, characterized in that: The concentration of the NaOH aqueous solution is 0.3-1 mol / L, the conditions of the solvent thermal reaction A are 140-220°C for 18-24 h, and the sodium titanate is Na2Ti2O5, Na2Ti3O7 or Na2Ti6O 13 One of them.

3. The method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material according to claim 1, characterized in that: The mass fraction of the ammonia water is 25%, and the volume ratio of water to ethanol in the mixed solution is (1-4):

1.

4. The method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material according to claim 1, characterized in that: The mass fraction of the formaldehyde aqueous solution is 37%; the stirring time for the mixed solution obtained by adding the formaldehyde aqueous solution and the polyphenol aqueous solution to the ammonia aqueous solution and stirring is 24 hours.

5. The method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material according to claim 1, characterized in that: The volume of the metal salt solution in the mixed metal salt solution obtained by adding the metal salt solution to the mixed solution and mixing: the volume of the polyphenol aqueous solution = 1: (10-20), the stirring time of the mixed metal salt solution obtained by adding the metal salt solution to the mixed solution and mixing is 12 hours, and the condition of the solvothermal reaction B is 24 hours at 100°C.

6. The method for preparing a polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material according to claim 1, characterized in that: The solvent thermal reaction A and the solvent thermal reaction B are both carried out in a reactor.

7. A polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material, characterized in that: The method is prepared by the method according to any one of claims 1 to 6.

8. A sodium ion battery, characterized in that: The negative electrode material uses the polyphenol-formaldehyde polymer chelated metal ion surface coating titanate material described in claim 7.

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