An antimony-based anode material for a new energy battery and its preparation method

Abstract

The present invention relates to the field of anode materials, and specifically to an antimony-based anode material for new energy batteries and a preparation method thereof. Carbon quantum dots, a surfactant, n-butanol, and cyclohexane are mixed evenly to obtain an organic phase. The organic phase is divided into two parts, denoted as organic phase A and organic phase B. An aqueous solution of antimony trichloride and an aqueous solution of ammonium metavanadate are added to organic phase A and organic phase B respectively to obtain microemulsion A and microemulsion B. Microemulsion A and microemulsion B are mixed, and after stirring at room temperature for 1-5 h, it is transferred to a hydrothermal reaction kettle, sealed and heated to 140-160 °C for reaction for 5-10 h. After returning to room temperature, the reaction solution is filtered, and the obtained product is washed with absolute ethanol and deionized water and then dried. The prepared antimony-based anode material is a composition of SbVO4 and carbon quantum dots, and the antimony-based anode material has a flower-like structure and is a very promising anode material for new energy batteries.

Description

Technical Field

[0001] The present invention relates to the field of anode materials, and specifically to an antimony-based anode material for new energy batteries and a preparation method thereof. Background Art

[0002] Lithium-ion batteries have the advantages of high voltage, good safety, long cycle life, no memory effect, and no pollution. They are one of the most widely studied new energy batteries. Their anode materials are mostly graphite and various carbon materials. However, research shows that carbon materials have disadvantages such as large energy loss and poor high-rate charge and discharge performance. Moreover, a passivation film is easily formed on the carbon anode in organic electrolytes, causing irreversible loss of the initial capacity. And the electrode potential of carbon materials is close to that of metallic lithium. When the battery is overcharged, metallic lithium is easily deposited on the surface of the carbon electrode, forming dendrites and causing short circuits. Therefore, finding better, more reliable, and new anode materials for new energy batteries has become the research direction of people.

[0003] Research in recent years has shown that metallic antimony has an extremely high initial theoretical lithium intercalation capacity, and the lithium intercalation potential is about 0.8V, which can effectively avoid the appearance of lithium dendrites and improve the safety performance of lithium-ion batteries. Moreover, the lithium absorption and release process of antimony has a flat electrochemical reaction platform, which can provide a very stable working voltage. Therefore, antimony-based anode materials have attracted great interest from researchers. Chinese Patent CN109473666A discloses a graphene-supported SbVO4 nanoparticle composite material and a preparation method thereof. This composite material has excellent electrochemical performance and exhibits high capacity and high-rate performance when applied to lithium-ion batteries and sodium-ion batteries. The preparation method has a simple process and is easy for large-scale production. However, how to further improve the structure of antimony-based anode materials, enhance their electrochemical performance, and broaden the application scenarios has become a research hotspot for scientific researchers. Summary of the Invention

[0004] Object of the Invention: Aiming at the above technical problems, the present invention provides an antimony-based anode material for new energy batteries and a preparation method thereof.

[0005] The technical solutions adopted are as follows:

[0006] A preparation method of an antimony-based anode material for new energy batteries is as follows:

[0007] Mix carbon quantum dots, surfactant, n-butanol, and cyclohexane to obtain an organic phase. Divide the organic phase into two parts, denoted as organic phase A and organic phase B. Add aqueous antimony trichloride solution and aqueous ammonium metavanadate solution to organic phase A and organic phase B respectively to obtain microemulsion A and microemulsion B. Mix microemulsion A and microemulsion B, stir at room temperature for 1 - 5 h, then transfer to a hydrothermal reaction kettle, seal and heat to 140 - 160 °C for reaction for 5 - 10 h. After restoring to room temperature, filter the reaction solution, and wash the obtained product with absolute ethanol and deionized water and then dry it to obtain the product;

[0008] The surfactant consists of cocamidopropyl betaine and an amino sulfonic acid type amphoteric surfactant;

[0009] The mass ratio of cocamidopropyl betaine to the amino sulfonic acid type amphoteric surfactant is 1 - 5:1 - 5;

[0010] The structural formula of the amino sulfonic acid type amphoteric surfactant is as follows:

[0011] ;

[0012] Among them, R1 and R2 are the same or different, and each independently is an alkyl group with a carbon atom number ≥ 4.

[0013] Further, the aqueous antimony trichloride solution contains a hydrolysis inhibitor.

[0014] Further, the hydrolysis inhibitor is hydrochloric acid.

[0015] Further, R1 and R2 are the same, and are any one of n-butyl, n-pentyl, and n-butyl.

[0016] Further, the preparation method of the amino sulfonic acid type amphoteric surfactant is as follows:

[0017] ;

[0018] S1: Carry out a ring-opening reaction between glycerol triglycidyl ether and 4-(dialkylamino)benzyl alcohol to obtain an intermediate;

[0019] ;

[0020] S2: Carry out a sulfonation reaction between the intermediate and 1,3-propane sultone to obtain the amino sulfonic acid type amphoteric surfactant.

[0021] Further, the temperature of the sulfonation reaction in S2 is 40 - 60 °C, and the time of the sulfonation reaction is 12 - 48 h.

[0022] The present invention also provides a new energy battery antimony-based anode material prepared by the above method. The antimony-based anode material is a composition of SbVO4 and carbon quantum dots, and the antimony-based anode material has a flower-like structure.

[0023] Advantages of the present invention:

[0024] The present invention provides a new energy battery antimony-based anode material, which is composed of SbVO4 and carbon quantum dots. It has good electrical conductivity and a special flower-like structure. The large specific surface area provides a continuous channel for electron transport, and at the same time can alleviate the volume change of the electrode material during the cycling process, improving the structural stability. It is a new energy battery anode material with great potential.

[0025] When preparing the antimony-based anode material by the microemulsion method, cocamidopropyl betaine and amino sulfonic acid-based amphoteric surfactants achieve the controllable preparation of the flower-like structure through a trinity mechanism of charge balance, template guidance, and dispersion stability, which can reduce side reactions and maintain the stability of the microemulsion during the high-temperature reaction process, ensuring the controllable synthesis of the morphology of the anode material. Description of the drawings

[0026] Figure 1 It is the SEM image of the antimony-based anode material prepared in Example 1. Detailed implementation manners

[0027] For those not specified in the examples, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial purchase. Technologies not mentioned in the present invention refer to the prior art. Unless otherwise specified, the following examples and comparative examples are parallel tests and adopt the same treatment steps and parameters.

[0028] Example 1:

[0029] A new energy battery antimony-based anode material is a composition of SbVO4 and carbon quantum dots and has a flower-like structure.

[0030] The preparation method of the above new energy battery antimony-based anode material is as follows:

[0031] Dissolve 1 g of sucrose in 50 ml of deionized water, stir at room temperature for 30 min, then put it into a polytetrafluoroethylene high-pressure reaction kettle, and carry out a sealed hydrothermal reaction at 180 °C for 5 h. After the hydrothermal reaction is completed, naturally cool to room temperature, pour the solution from the kettle into a centrifuge tube, centrifuge at a speed of 12,000 r / min for 10 min to precipitate large particles, pour out the supernatant, separate the solution with a dialysis bag (500 Da), and finally freeze-dry the solution for 48 h to obtain carbon quantum dots;

[0032] Mix 0.01 g of carbon quantum dots, 2.5 g of cocamidopropyl betaine, 2.5 g of amino sulfonic acid amphoteric surfactant, 10 ml of n-butanol, and 100 ml of cyclohexane to obtain an organic phase. Divide the organic phase into two equal parts and label them as organic phase A and organic phase B. Add 5 ml of 0.1 mol / L antimony trichloride aqueous solution and 5 ml of 0.1 mol / L ammonium metavanadate aqueous solution to organic phase A and organic phase B respectively to obtain microemulsion A and microemulsion B. The pH of the antimony trichloride aqueous solution is adjusted to 2 with 0.1 mol / L hydrochloric acid in advance. Mix microemulsion A and microemulsion B, stir at room temperature for 2 h, then transfer to a hydrothermal reaction kettle, seal and heat to 140 °C for reaction for 10 h. After restoring to room temperature, filter the reaction solution. The obtained product is washed repeatedly with absolute ethanol and deionized water and then dried in vacuum at 50 °C for 24 h. In order to study the morphology and microstructure of the prepared antimony-based anode material for new energy batteries, it is observed by scanning electron microscopy. For details, see Figure 1 ;

[0033] Among them, the structural formula of the amino sulfonic acid amphoteric surfactant is as follows:

[0034] ;

[0035] The specific preparation method is as follows:

[0036] ;

[0037] S1: Heat the mixed system of 0.1 mol of metallic potassium and 0.9 mol of 4-(dibutylamino)benzyl alcohol to 70 °C and react for 30 min. Then slowly add 0.3 mol of glycerol triglycidyl ether. After the addition is complete, heat to 85 °C and continue to react for 12 h. After the reaction is completed, cool the system to room temperature. Neutralize the reaction solution with 100 ml of 15% hydrochloric acid solution by mass. Then add 1000 ml of dichloromethane and 1000 ml of water. Stir rapidly for 30 min and then separate the organic layer and dry it with anhydrous magnesium sulfate. Remove small molecules by vacuum distillation to obtain an intermediate;

[0038] ;

[0039] S2: Under nitrogen protection, add 0.01 mol of the intermediate and 0.04 mol of sodium hydride to 100 ml of dry tetrahydrofuran. Stir and dissolve evenly, then raise the temperature of the water bath to 40 °C. Slowly dropwise add 0.04 mol of 1,3-propane sultone. After the addition is complete, stir for the sulfonation reaction for 24 h. Remove the water bath and add 50 ml of methanol to remove the unreacted sodium hydride. Remove small molecules by vacuum concentration. Then add 250 ml of deionized water and extract 3 times with 150 ml of n-butanol. Combine the organic phases and concentrate under reduced pressure to obtain the amino sulfonic acid amphoteric surfactant.

[0040] Example 2:

[0041] A new energy battery antimony-based anode material is a composition of SbVO4 and carbon quantum dots and has a flower-like structure.

[0042] The preparation method of the above new energy battery antimony-based anode material is as follows:

[0043] Dissolve 1 g of sucrose in 50 ml of deionized water, stir at room temperature for 30 min, then put it into a polytetrafluoroethylene high-pressure reaction kettle, carry out a sealed hydrothermal reaction at 180 °C for 5 h. After the hydrothermal reaction is completed, naturally cool to room temperature, pour the solution from the kettle into a centrifuge tube, centrifuge at a speed of 12,000 r / min for 10 min to precipitate large particles, pour out the supernatant, separate the solution with a dialysis bag (500 Da), and finally freeze-dry the solution for 48 h to obtain carbon quantum dots;

[0044] Mix 0.01 g of carbon quantum dots, 2.5 g of cocamidopropyl betaine, 2.5 g of amino sulfonic acid type amphoteric surfactant, 10 ml of n-butanol, and 100 ml of cyclohexane to obtain an organic phase. Divide the organic phase into two equal parts and label them as organic phase A and organic phase B. Add 5 ml of 0.1 mol / L antimony trichloride aqueous solution and 5 ml of 0.1 mol / L ammonium metavanadate aqueous solution to organic phase A and organic phase B respectively to obtain microemulsion A and microemulsion B. The pH of the antimony trichloride aqueous solution is adjusted to 2 with 0.1 mol / L hydrochloric acid in advance. Mix microemulsion A and microemulsion B, stir and react at room temperature for 2 h, then transfer to a hydrothermal reaction kettle, seal and heat up to 150 °C and react for 10 h. After restoring to room temperature, filter the reaction solution, and wash the obtained product repeatedly with absolute ethanol and deionized water and then dry it in vacuo at 50 °C for 24 h;

[0045] Among them, the structural formula and preparation method of the amino sulfonic acid type amphoteric surfactant are the same as those in Example 1.

[0046] Example 3:

[0047] A new energy battery antimony-based anode material is a composition of SbVO4 and carbon quantum dots and has a flower-like structure.

[0048] The preparation method of the above new energy battery antimony-based anode material is as follows:

[0049] Dissolve 1 g of sucrose in 50 ml of deionized water, stir at room temperature for 30 min, then put it into a polytetrafluoroethylene high-pressure reaction kettle, carry out a sealed hydrothermal reaction at 180 °C for 5 h. After the hydrothermal reaction is completed, naturally cool to room temperature, pour the solution from the kettle into a centrifuge tube, centrifuge at a speed of 12,000 r / min for 10 min to precipitate large particles, pour out the supernatant, separate the solution with a dialysis bag (500 Da), and finally freeze-dry the solution for 48 h to obtain carbon quantum dots;

[0050] Mix 0.01 g of carbon quantum dots, 2.5 g of cocamidopropyl betaine, 2.5 g of amino sulfonic acid-based amphoteric surfactant, 10 ml of n-butanol, and 100 ml of cyclohexane to obtain an organic phase. Divide the organic phase into two equal parts and label them as organic phase A and organic phase B. Add 5 ml of 0.1 mol / L antimony trichloride aqueous solution and 5 ml of 0.1 mol / L ammonium metavanadate aqueous solution to organic phase A and organic phase B respectively to obtain microemulsion A and microemulsion B. The pH of the antimony trichloride aqueous solution is adjusted to 2 with 0.1 mol / L hydrochloric acid in advance. Mix microemulsion A and microemulsion B, stir at room temperature for 2 h, then transfer to a hydrothermal reaction kettle, seal and heat to 160 °C for reaction for 10 h. After restoring to room temperature, filter the reaction solution. The obtained product is washed repeatedly with absolute ethanol and deionized water and then dried in vacuum at 50 °C for 24 h to obtain the product;

[0051] Among them, the structural formula and preparation method of the amino sulfonic acid-based amphoteric surfactant are the same as those in Example 1.

[0052] Comparative Example 1:

[0053] It is basically the same as Example 1, except that carbon quantum dots are not added.

[0054] Comparative Example 2:

[0055] It is basically the same as Example 1, except that the preparation method of the antimony-based negative electrode material for new energy batteries is as follows:

[0056] Dissolve 1 g of sucrose in 50 ml of deionized water, stir at room temperature for 30 min, then put it into a polytetrafluoroethylene high-pressure reaction kettle, and carry out hydrothermal reaction at 180 °C for 5 h under sealed conditions. After the hydrothermal reaction is completed, naturally cool to room temperature, pour the solution from the kettle into a centrifuge tube, centrifuge at a speed of 12,000 r / min for 10 min to precipitate large particles, pour out the supernatant, separate the solution with a dialysis bag (500 Da), and finally freeze-dry the solution for 48 h to obtain carbon quantum dots;

[0057] Mix 0.01 g of carbon quantum dots, 5 ml of 0.1 mol / L antimony trichloride aqueous solution and 5 ml of 0.1 mol / L ammonium metavanadate aqueous solution. The pH of the antimony trichloride aqueous solution is adjusted to 2 with 0.1 mol / L hydrochloric acid. Stir at room temperature for 2 h, then transfer to a hydrothermal reaction kettle, seal and heat to 140 °C for reaction for 10 h. After restoring to room temperature, filter the reaction solution. The obtained product is washed repeatedly with absolute ethanol and deionized water and then dried in vacuum at 50 °C for 24 h to obtain the product. In order to study the morphology and microstructure of the prepared antimony-based negative electrode material, it is observed by scanning electron microscopy and shown to be a nanoparticle-like structure.

[0058] Performance test:

[0059] The CR2025 button battery was prepared in a glove box filled with argon. The antimony-based anode materials of the new energy batteries prepared in Examples 1-3 and Comparative Examples 1-2 of the present invention were respectively mixed with sodium alginate and acetylene black carbon powder in a mass ratio of 7:2:1 in an appropriate amount of water to produce electrode materials. The synthesized slurry was coated on a copper foil with a thickness of 150 μm, placed in a vacuum oven, dried at 110 °C for 12 h, and then the electrode was punched into a circular thin sheet with a diameter of 12 mm and pressed tightly with a small press at a pressure of 10 Mpa to enhance the contact between the material and the copper foil. The separator used was a Celgard 2300 membrane, and the counter electrode used was pure lithium. 1 mol of lithium hexafluorophosphate was dissolved in 1 L of a mixed organic solvent of diethyl carbonate (DEC) / ethylene carbonate (EC) / dimethyl carbonate (DMC) (V(DEC):V(EC):V(DMC)=1:1:1) as the electrolyte. The electrochemical performance was tested on a Blue Electric battery test system, and cyclic voltammetry (CV) tests were carried out on a CH1600E electrochemical workstation at a voltage of 0.05 - 3.00 V and a current density of 1 A / g. The test results are shown in Table 1 below:

[0060]

[0061] As can be seen from Table 1 above, the antimony-based anode materials prepared by the present invention have relatively excellent electrochemical performance;

[0062] Through the comparison of Examples 1-3, it can be seen that the electrochemical performance of the antimony-based anode materials prepared at different temperatures is slightly different. When the hydrothermal reaction is at 150 °C, the antimony-based anode material has the optimal electrochemical performance;

[0063] Through the comparison of Example 1 with Comparative Examples 1-2, it can be seen that both the carbon quantum dots and the preparation method adopted in the present invention have played a positive role in improving the electrochemical performance of the antimony-based anode materials.

[0064] The above examples are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing examples, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing examples, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A preparation method of an antimony-based anode material for a new energy battery, characterized in that, The specific steps are as follows: Mix carbon quantum dots, surfactant, n-butanol, and cyclohexane to obtain an organic phase. Divide the organic phase into two parts, denoted as organic phase A and organic phase B. Add aqueous antimony trichloride solution and aqueous ammonium metavanadate solution to organic phase A and organic phase B respectively to obtain microemulsion A and microemulsion B. Mix microemulsion A and microemulsion B, stir and react at room temperature for 1 - 5 h, then transfer to a hydrothermal reaction kettle, seal and heat to 140 - 160 °C for reaction for 5 - 10 h. After restoring to room temperature, filter the reaction solution, and wash the obtained product with absolute ethanol and deionized water and then dry it; The surfactant is composed of cocamidopropyl betaine and an amino sulfonic acid type amphoteric surfactant; The mass ratio of cocamidopropyl betaine to the amino sulfonic acid type amphoteric surfactant is 1 - 5:1 - 5; The structural formula of the amino sulfonic acid type amphoteric surfactant is as follows: ； Among them, R1 and R2 are the same, being n-butyl or n-pentyl; The preparation method of the amino sulfonic acid type amphoteric surfactant is as follows: ； S1: Carry out a ring-opening reaction between glycerol triglycidyl ether and 4-(dialkylamino)benzyl alcohol to obtain an intermediate; ； S2: Carry out a sulfonation reaction between the intermediate and 1,3-propane sultone to obtain the amino sulfonic acid type amphoteric surfactant; The temperature of the sulfonation reaction in S2 is 40 - 60 °C, and the time of the sulfonation reaction is 12 - 48 h; The antimony-based anode material prepared by the above method is a composition of SbVO4 and carbon quantum dots, and the antimony-based anode material has a flower-like structure.

2. The preparation method of the antimony-based anode material for new energy batteries according to claim 1, characterized in that, The aqueous antimony trichloride solution contains a hydrolysis inhibitor.

3. The preparation method of the antimony-based anode material for new energy batteries according to claim 2, characterized in that, The hydrolysis inhibitor is hydrochloric acid.

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