Tin-based high-entropy material for negative electrode of sodium-ion battery and preparation method and application of tin-based high-entropy material

Abstract

The invention relates to the field of sodium ion batteries, in particular to a tin-based high-entropy material for a sodium ion battery negative electrode, which comprises a high-entropy (Ti1 / 4Nb1 / 4V1 / 4Zr1 / 4) 2SnC material, Super P and a carbon material. The prepared material has the advantages of excellent comprehensive electrochemical performance, excellent stability, good air stability and conductivity, high rate and the like. Meanwhile, a large batch of high-entropy (Ti1 / 4Nb1 / 4V1 / 4Zr1 / 4) 2SnC materials are simply and efficiently prepared in combination with a self-propagating high-temperature solid-phase one-step method, and the material and the preparation method promote rapid development of layered high-entropy tin-based sodium-ion battery negative electrode materials. The application of the high-entropy tin compound also opens up a new way for developing other high-entropy materials, and further development of an electrochemical energy storage technology is promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of sodium ion battery material preparation, and in particular to a tin-based high entropy material for a negative electrode of a sodium ion battery, and a preparation method and application thereof. Background Art

[0002] With the rapid development of renewable energy and the increasing demand for efficient energy storage systems, sodium-ion batteries have gradually attracted attention as a potential alternative to lithium-ion batteries. Sodium-ion batteries have the advantages of abundant resources, low cost and environmental friendliness, especially in areas where sodium resources are relatively abundant, their economic performance is significantly better than that of lithium-ion batteries.

[0003] In the research of negative electrode materials for sodium ion batteries, tin-based high entropy MAX phase materials (M 2 SnC (M is a transition metal) has attracted much attention due to its unique layered structure and excellent electrochemical properties. MAX phase materials are a class of materials with chemical diversity and excellent mechanical properties, usually composed of early transition metals (M), A group elements (such as aluminum, tin, sulfur, etc.) and carbon, nitrogen or boron (X). The layered structure of these materials enables them to maintain good structural stability during the insertion and deinsertion of lithium or sodium.

[0004] The design concept of high-entropy MAX phase materials is to maximize the configurational entropy of the material by introducing a variety of main elements, thereby achieving stronger material performance. Studies have shown that tin, as a low-melting-point metal of the A-site element, can effectively improve the self-healing ability and electrochemical performance of MAX phase materials. In addition, the rich composition and low formation energy of tin-based high-entropy MAX phase materials provide a good foundation for the negative electrode materials of sodium-ion batteries.

[0005] In sodium-ion batteries, the electrochemical properties of tin-based high-entropy MAX phase materials are affected by their crystal structure, elemental composition, and interactions. Studies have found that these materials exhibit high specific capacity and good cycle stability during charge and discharge, and are suitable for sodium-ion batteries with high energy density and high power output. By adjusting the composition and structure of the material, its conductivity and ion mobility can be further optimized, thereby improving the overall performance of the battery. In short, tin-based high-entropy MAX phase materials have broad application prospects in sodium-ion batteries. With in-depth research on the relationship between their structure and performance, this type of material is expected to provide new solutions for future energy storage technologies. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention provides a tin-based high-entropy material for the negative electrode of a sodium ion battery and its preparation method and application, which can obtain a high-purity product and have excellent electrochemical properties. Specifically, the material exhibits excellent long-cycle stability, can effectively alleviate the volume expansion problem during the charging and discharging process, thereby extending the battery life. The material also has good electrical conductivity, can promote the rapid transmission of electrons and sodium ions, and further improve the overall performance of the battery.

[0007] To achieve the above objectives, the present invention is implemented by the following technical scheme: A method for preparing a tin-based high entropy material for a negative electrode of a sodium ion battery, comprising the following steps:

[0008] Step 1: adding transition metal powder, tin powder and tin-carbon powder into a ball mill according to a stoichiometric ratio of 2:1:1, and performing ball milling to obtain a first mixed system;

[0009] Step 2: Put the first mixed system into a graphite crucible with a boron nitride coated inner surface and press it into a block, then put it into a self-propagating high temperature reactor, and synthesize a block material through a self-propagating high temperature reaction under the protection of an inert gas to obtain a second mixed system;

[0010] Step 3, the obtained second mixed system is put into a ball mill for crushing, and then sieved to obtain a solid solution material to obtain a third mixed system;

[0011] Step 4: The obtained third mixed system material is subjected to acid etching, washed with water until neutral, and then an intercalation agent is added for ultrasonic treatment, and then centrifuged and dried to obtain a high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 SnC material.

[0012] Step 5: Get the high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 SnC materials, using solvents to convert high entropy (Ti 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 The SnC material, the binder and the carbon material are mixed uniformly, put into a mortar and ground to obtain a fourth mixed system.

[0013] Step 6: Evenly scrape the obtained fourth mixed system onto Cu foil to a thickness of 5-8 um, dry in vacuum, and punch out into electrode sheets.

[0014] Preferably, the transition metal powder includes four or more of titanium powder, niobium powder, vanadium powder, chromium powder, zirconium powder, molybdenum powder and tantalum powder.

[0015] Preferably, the ball milling speed is 300-400 rpm and the time is 12-14 hours.

[0016] Preferably, the inert gas is argon.

[0017] Preferably, the acid is hydrochloric acid, the intercalant is dimethyl sulfoxide, the ultrasonic machine frequency is 40KHz at 20-30°C for 24 hours, and the drying temperature is 80°C for 14 hours.

[0018] Preferably, the solvent in step 5 is N-methylpyrrolidone (NMP), the binder is polyvinylidene fluoride, and the carbon material is Super P. 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 The SnC material, the binder and the carbon material are mixed evenly, and the mixing mass ratio is 7:2:1.

[0019] Preferably, in step six, the vacuum drying temperature is 80° C., the time is 24 h, and the electrode sheet is a circular electrode sheet with a diameter of 12 mm.

[0020] The present invention provides a tin-based high entropy material for a negative electrode of a sodium ion battery and a preparation method and application thereof. The material has the following beneficial effects:

[0021] 1. The present invention adopts a self-propagating high temperature solid phase one-step method to efficiently and simply prepare a large number of high-purity tin-based high entropy (Ti 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 SnC material. This material exhibits excellent performance in many aspects in the application of sodium ion battery negative electrode. First, the unique composition and structure of the high entropy material give it good electrical conductivity and electron transport properties, significantly accelerating the sodium ion deintercalation process, thereby improving the battery's charge and discharge efficiency. Secondly, its layered structure can effectively buffer the volume expansion generated when sodium ions are embedded, reduce structural damage during the cycle, and greatly improve the battery's cycle stability and service life. In addition, the element diversity and crystal defects brought about by the high entropy effect provide rich active sites, significantly enhancing the storage capacity of sodium ions, making the negative electrode material outstanding in terms of discharge specific capacity and rate performance. Experiments show that the tin-based high entropy negative electrode material exhibits excellent rate performance. In summary, the present invention provides a high-efficiency, high-purity tin-based high entropy negative electrode material and a preparation method thereof, which provides a new solution for improving the performance of sodium ion batteries and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is an XRD refinement diagram of the tin-based high entropy negative electrode material of the present invention;

[0023] Figure 2 The tin-based high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 EDS surface scanning mapping of SnC negative electrode material;

[0024] Figure 3 is the tin-based intermediate entropy (T i 1 / 3 Nb 1 / 3 V 1 / 3 ) 2 EDS surface scanning mapping of SnC negative electrode material;

[0025] Figure 4 The tin-based Ti 2 EDS surface scanning mapping of SnC anode material. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Embodiment 1:

[0028] The embodiment of the present invention provides a tin-based high entropy negative electrode material (Ti) for a sodium ion battery 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 SnC preparation, the steps are as follows:

[0029] (1) Add transition metal powders (Ti, Nb, V, Zr), tin powder and carbon powder in a stoichiometric ratio of 2:1:1 into a ball mill and perform ball milling under an argon atmosphere at a speed of 400 rpm for 12 hours to obtain a first mixed system;

[0030] (2) placing the first mixed system into a graphite crucible coated with boron nitride on the inner surface and pressing it into a block, and then placing it into a self-propagating high-temperature reactor, and synthesizing a block material through a self-propagating high-temperature reaction under the protection of argon gas to obtain a second mixed system;

[0031] (3) The obtained second mixed system was put into a ball mill at a speed of 300 rpm for 12 h for pulverization. After pulverization, it was sieved through a 500-mesh sieve to obtain a solid solution powder material, thereby obtaining a third mixed system;

[0032] (4) The obtained third mixed system material is treated with hydrochloric acid at a concentration of 3 mol / L, washed with water until neutral, and then added with dimethyl sulfoxide, ultrasonicated at 20-30°C for 24 hours, centrifuged and dried at 80°C for 14 hours to obtain a high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 SnC material.

[0033] (5) The obtained high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 SnC negative electrode material, conductive agent (Super P) and binder (PVDF) were mixed evenly at a mass ratio of 7:2:1, and N-methylpyrrolidone (NMP) was used as a solvent to make a negative electrode slurry, and then the negative electrode slurry was evenly scraped on the Cu foil. The solvent was heated in a vacuum drying oven at a temperature of 80°C for 24 hours to remove the solvent. The negative electrode was cut into discs with a diameter of 12 mm.

[0034] (6) Prepare the high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 ) 2 The SnC negative electrode material pole piece, diaphragm, lithium sheet, spring, gasket, positive electrode shell and negative electrode shell were assembled into a battery in a glove box and the electrochemical performance test was carried out. The results are shown in Figure 3 The results show that the transition metal elements Ti, Nb, V and Sn are almost uniformly distributed in the high entropy phase, and the concentrations of the above metal atoms in the atomic layer are detected to be 14.2at.%, 20.5at.%, 15.3at.% and 23.6at.%, respectively.

[0035] High entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Zr1 / 4 ) 2 The XRD pattern of SnC negative electrode material is shown in Figure 1 It can be seen that the target product has characteristic peaks at 12.88°, 32.42°, 38.48° and 55.45°, which correspond to the (002), (100), (103) and (110) crystal planes of the standard card, indicating the successful preparation of high entropy materials. EDS surface scanning mapping Figure 2 It shows that the transition metal elements Ti, V, Zr, Nb and Sn are almost uniformly distributed in the high entropy phase, and the concentrations of the above metal atoms in the atomic layer were detected to be 9.2at.%, 10.8at.%, 11.5at.%, 18.5at.% and 21.7at.%, respectively, which are in the range of 5-35at.%, which is consistent with the definition of a high entropy system.

[0036] Embodiment 2:

[0037] The embodiment of the present invention provides a tin-based high entropy negative electrode material (Ti) for a sodium ion battery 1 / 4 Nb 1 / 4 V 1 / 4 Mo 1 / 4 ) 2 SnC preparation, the steps are as follows:

[0038] (1) Add transition metal powders (Ti, Nb, V, Mo), tin powder and carbon powder in a stoichiometric ratio of 2:1:1 into a ball mill and perform ball milling under an argon atmosphere at a speed of 400 rpm for 12 hours to obtain a first mixed system;

[0039] (2) placing the first mixed system into a graphite crucible coated with boron nitride on the inner surface and pressing it into a block, and then placing it into a self-propagating high-temperature reactor, and synthesizing a block material through a self-propagating high-temperature reaction under the protection of argon gas to obtain a second mixed system;

[0040] (3) The obtained second mixed system was put into a ball mill at a speed of 300 rpm for 12 h for pulverization. After pulverization, it was sieved through a 500-mesh sieve to obtain a solid solution powder material, thereby obtaining a third mixed system;

[0041] (4) The obtained third mixed system material is treated with hydrochloric acid at a concentration of 3 mol / L, washed with water until neutral, and then added with dimethyl sulfoxide, ultrasonicated at 20-30°C for 24 hours, centrifuged and dried at 80°C for 14 hours to obtain a high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Mo 1 / 4 ) 2 SnC material.

[0042] (5) The obtained high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Mo 1 / 4 ) 2 SnC negative electrode material, conductive agent (Super P) and binder (PVDF) were mixed evenly at a mass ratio of 7:2:1, and N-methylpyrrolidone (NMP) was used as a solvent to make a negative electrode slurry, and then the negative electrode slurry was evenly scraped on the Cu foil. The solvent was heated in a vacuum drying oven at a temperature of 80°C for 24 hours to remove the solvent. The negative electrode was cut into discs with a diameter of 12 mm.

[0043] (6) The prepared high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Mo 1 / 4 ) 2 The pole pieces, diaphragms, lithium sheets, springs, gaskets, positive electrode shells and negative electrode shells of SnC negative electrode materials were assembled into batteries in a glove box for electrochemical performance testing.

[0044] Embodiment three:

[0045] The embodiment of the present invention provides a tin-based high entropy negative electrode material (Ti) for a sodium ion battery 1 / 4 Nb 1 / 4 V 1 / 4 Mo 1 / 4 ) 2 SnC preparation, the steps are as follows:

[0046] (1) Add transition metal powders (Ti, Nb, V, Cr), tin powder and carbon powder in a stoichiometric ratio of 2:1:1 into a ball mill and perform ball milling under an argon atmosphere at a speed of 400 rpm for 12 hours to obtain a first mixed system;

[0047] (2) placing the first mixed system into a graphite crucible coated with boron nitride on the inner surface and pressing it into a block, and then placing it into a self-propagating high-temperature reactor, and synthesizing a block material through a self-propagating high-temperature reaction under the protection of argon gas to obtain a second mixed system;

[0048] (3) The obtained second mixed system was put into a ball mill at a speed of 300 rpm for 12 h for pulverization. After pulverization, it was sieved through a 500-mesh sieve to obtain a solid solution powder material, thereby obtaining a third mixed system;

[0049] (4) The obtained third mixed system material is treated with hydrochloric acid at a concentration of 3 mol / L, washed with water until neutral, and then added with dimethyl sulfoxide, ultrasonicated at 20-30°C for 24 hours, centrifuged and dried at 80°C for 14 hours to obtain a high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Mo 1 / 4 ) 2 SnC material.

[0050] (5) The obtained high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Mo 1 / 4 ) 2 SnC negative electrode material, conductive agent (Super P) and binder (PVDF) were mixed evenly at a mass ratio of 7:2:1, and N-methylpyrrolidone (NMP) was used as a solvent to make a negative electrode slurry, and then the negative electrode slurry was evenly scraped on the Cu foil. The solvent was heated in a vacuum drying oven at a temperature of 80°C for 24 hours to remove the solvent. The negative electrode was cut into discs with a diameter of 12 mm.

[0051] (6) Prepare the high entropy (T i 1 / 4 Nb 1 / 4 V 1 / 4 Mo 1 / 4 ) 2 The pole pieces, diaphragms, lithium sheets, springs, gaskets, positive electrode shells and negative electrode shells of SnC negative electrode materials were assembled into batteries in a glove box for electrochemical performance testing.

[0052] Comparative Example 1:

[0053] The comparative example of the present invention provides a sodium ion battery tin-based medium entropy negative electrode material (Ti 1 / 3 Nb 1 / 3 V 1 / 4 Mo 1 / 3 ) 2 SnC preparation, the steps are as follows:

[0054] (1) Add transition metal powders (Ti, Nb, V), tin powder and carbon powder in a stoichiometric ratio of 2:1:1 into a ball mill and perform ball milling under an argon atmosphere at a speed of 400 rpm for 12 h.

[0055] A first mixed system is obtained;

[0056] (2) placing the first mixed system into a graphite crucible coated with boron nitride on the inner surface and pressing it into a block, and then placing it into a self-propagating high-temperature reactor, and synthesizing a block material through a self-propagating high-temperature reaction under the protection of argon gas to obtain a second mixed system;

[0057] (3) The obtained second mixed system was put into a ball mill at a speed of 300 rpm for 12 h for pulverization. After pulverization, it was sieved through a 500-mesh sieve to obtain a solid solution powder material, thereby obtaining a third mixed system;

[0058] (4) The obtained third mixed system material is treated with hydrochloric acid at a concentration of 3 mol / L, washed with water until neutral, and then added with dimethyl sulfoxide, ultrasonicated at 20-30°C for 24 hours, centrifuged and dried at 80°C for 14 hours to obtain the intermediate entropy (T i 1 / 3 Nb 1 / 3 V 1 / 4 Mo 1 / 3 ) 2 SnC material.

[0059] (5) The obtained intermediate entropy (T i 1 / 3 Nb 1 / 3 V 1 / 4 Mo 1 / 3 ) 2 SnC negative electrode material, conductive agent (Super P) and binder (PVDF) were mixed evenly at a mass ratio of 7:2:1, and N-methylpyrrolidone (NMP) was used as a solvent to make a negative electrode slurry, and then the negative electrode slurry was evenly scraped on the Cu foil. The solvent was heated in a vacuum drying oven at a temperature of 80°C for 24 hours to remove the solvent. The negative electrode was cut into discs with a diameter of 12 mm.

[0060] (6) Prepare the medium entropy (T i 1 / 3 Nb 1 / 3 V 1 / 4 Mo 1 / 3 ) 2 The SnC negative electrode material pole piece, separator, lithium sheet, spring, gasket, positive electrode shell and negative electrode shell were assembled into a battery in a glove box for electrochemical performance testing.

[0061] Comparative Example 1 prepared mesentropy (T i 1 / 3 Nb 1 / 3 V 1 / 4 Mo 1 / 3 ) 2 The XRD pattern of SnC negative electrode material is shown in Figure 1It can be seen that the target product has characteristic peaks at 13.01°, 32.91°, 38.64° and 56.94°, which correspond to the standard card (002), (100), (103) and (110) crystal planes, respectively, indicating the successful preparation of the medium entropy material. EDS surface scanning mapping Figure 3 It shows that transition metal elements Ti, V, Nb and Sn are almost uniformly distributed in the high entropy phase.

[0062] Comparative Example 2:

[0063] The comparative example of the present invention provides a sodium ion battery tin-based negative electrode material Ti 2 SnC preparation, the steps are as follows:

[0064] (1) Add transition metal powder Ti powder, tin powder and carbon powder into a ball mill at a stoichiometric ratio of 2:1:1, and perform ball milling under argon atmosphere at a speed of 400 rpm for 12 h.

[0065] A first mixed system is obtained;

[0066] (2) placing the first mixed system into a graphite crucible coated with boron nitride on the inner surface and pressing it into a block, and then placing it into a self-propagating high-temperature reactor, and synthesizing a block material through a self-propagating high-temperature reaction under the protection of argon gas to obtain a second mixed system;

[0067] (3) The obtained second mixed system was put into a ball mill at a speed of 300 rpm for 12 h for pulverization. After pulverization, it was sieved through a 500-mesh sieve to obtain a solid solution powder material, thereby obtaining a third mixed system;

[0068] (4) The obtained third mixed system material is treated with hydrochloric acid at a concentration of 3 mol / L, washed with water until neutral, and then added with dimethyl sulfoxide, ultrasonicated at 20-30°C for 24 hours, centrifuged and dried at 80°C for 14 hours to obtain Ti 2 SnC material.

[0069] (5) The obtained Ti 2 SnC negative electrode material, conductive agent (Super P) and binder (PVDF) were mixed evenly at a mass ratio of 7:2:1, and N-methylpyrrolidone (NMP) was used as a solvent to make a negative electrode slurry, and then the negative electrode slurry was evenly scraped on the Cu foil. The solvent was heated in a vacuum drying oven at a temperature of 80°C for 24 hours to remove the solvent. The negative electrode was cut into discs with a diameter of 12 mm.

[0070] (6) Prepare the Ti 2The pole pieces, diaphragms, lithium sheets, springs, gaskets, positive electrode shells and negative electrode shells of SnC negative electrode materials were assembled into batteries in a glove box for electrochemical performance testing.

[0071] Tin-based high entropy anode materials (Ti 1 / 4 Nb 1 / 4 V 1 / 4 Cr 1 / 4 ) 2 SnC has shown outstanding application potential in the field of sodium-ion batteries. This material not only achieves an efficient preparation process through the combination of multiple elements, but also enhances its electrochemical properties. The high entropy effect gives the material excellent thermodynamic stability, significantly improving the cycle life during multiple charge and discharge processes. In addition, the lattice distortion effect promotes the effective nucleation and uniform growth of sodium ions, ensuring the structural integrity of the electrode material during long-term use. This type of tin-based high-entropy material shows outstanding advantages in kinetics, especially the hysteresis diffusion effect reflected in the sodium ion diffusion process, which significantly improves its rate performance and enables it to maintain good electrochemical response at high current density. In the electrochemical performance evaluation, the material has a discharge specific capacity of 495mAh / g at a current density of 400mA / g, which is much higher than conventional negative electrode materials. In short, tin-based high-entropy negative electrode materials have shown wide application potential in the field of sodium-ion batteries with their efficient preparation process, excellent electrochemical properties and good cycle stability, providing new ideas and solutions for the advancement of future lithium and sodium battery technologies.

[0072] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A tin-based high entropy material for a negative electrode of a sodium ion battery, characterized in that: The negative electrode material of the lithium ion battery includes a high entropy material (Ti 1 / 4 Nb 1 / 4 V 1 / 4 Zr 1 / 4 )2SnC, a binder and a carbon material; The preparation method of the high entropy material comprises the following steps: Step 1: adding transition metal powder, tin powder and carbon powder into a ball milling jar, milling at a speed of 300-400 rpm for 12-14 hours to obtain a first mixed system; Step 2: Put the first mixed system into a graphite crucible with a boron nitride coated inner surface and press it into a block, then put it into a self-propagating high temperature reactor, and synthesize a block material through a self-propagating high temperature reaction under the protection of an inert gas to obtain a second mixed system; Step 3, the obtained second mixed system is put into a ball mill for crushing, and then sieved to obtain a solid solution powder material to obtain a third mixed system; Step 4: subjecting the obtained third mixed system material to acid etching treatment, washing with water to neutrality after the treatment, adding an intercalating agent to conduct ultrasonic treatment, centrifuging and drying after the treatment to obtain a high entropy material.

2. The tin-based high entropy material for a negative electrode of a sodium ion battery according to claim 1, characterized in that: The transition metal powder is any four of Ti, Nb, V, Zr, Mo, Ta, and Cr, and the molar ratio of the transition metal powder, tin powder, and carbon powder is 2:1:1 to achieve the synthesis of high entropy materials.

3. The tin-based high entropy material for a negative electrode of a sodium ion battery according to claim 1, characterized in that: The acid used in the acid etching treatment is any one or a combination of sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, and hydrofluoric acid, and the intercalation agent is any one or a combination of alcohol, potassium acetate, dimethyl sulfoxide, urea, formamide, and alkylamine.

4. The tin-based high entropy material for a negative electrode of a sodium ion battery according to claim 1, characterized in that: The binder is any one or a combination of polyvinylidene fluoride, polyvinyl alcohol, styrene-butadiene rubber and polytetrafluoroethylene.

5. The tin-based high entropy material for a negative electrode of a sodium ion battery according to claim 1, characterized in that: The carbon material is any one or a combination of conductive carbon black, Ketjen black, carbon nanotubes, acetylene black and Super P.

6. The tin-based high entropy material for a negative electrode of a sodium ion battery according to claim 1, characterized in that: The mass ratio of the high entropy material, the binder and the carbon material is 7:2:

1.

7. The method for preparing a tin-based high entropy material for a negative electrode of a sodium ion battery according to claim 1, characterized in that: The method comprises the following steps: weighing raw materials according to the formula of high entropy negative electrode materials for sodium ion batteries, mixing high entropy materials, binders and carbon materials evenly with a solvent, then coating them evenly on a Cu foil, vacuum drying and punching them into electrode sheets.

8. The method for preparing a tin-based high entropy material for a negative electrode of a sodium ion battery according to claim 7, characterized in that: The vacuum drying process was carried out at a temperature of 80° C. and for 24 hours.

9. The method for preparing a tin-based high entropy material for a negative electrode of a sodium ion battery according to claim 7, characterized in that: The electrode sheet is a small circular electrode sheet with a diameter of 12 mm.

10. Application of the tin-based high entropy material for sodium ion battery negative electrode according to any one of claims 1 to 6 in sodium ion batteries.

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