A CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material and its preparation method

Abstract

The invention discloses a CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material and a preparation method thereof. The method comprises: 1. adding 1-2 mmol of CuCl2·2H2O and 3-5 mmol of thioacetamide to 40-60 mL of deionized water, and ultrasonically dispersing to obtain a mixed solution A; 2. adding 0.5-2 mmol of melamine to the mixed solution A, and fully stirring to obtain a uniform mixed solution B; 3. placing the mixed solution B in a hydrothermal kettle, and fully reacting at 160-200° C., and drying to obtain CuSx. x @ melamine precursor; 4. CuS x A melamine precursor was placed in a reactor and heated from room temperature to 400-440°C at a rate of 2°C / min under an argon atmosphere. The temperature was then maintained and cooled to room temperature to obtain a CuSx@ nitrogen-doped carbon hollow nanorod structured sodium-ion battery anode material, which can improve the conductivity, rate performance, and service life of sodium-ion batteries.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite materials, and specifically is a CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material and a preparation method thereof. Background Art

[0002] In the past few decades, lithium-ion batteries (LIBs) have dominated the energy storage device market due to their high energy and power density, long life, safety and reliability. However, the high cost and scarcity of lithium resources have hindered the further development of lithium-ion batteries (LIBs). As an effective alternative that is environmentally friendly and resource-rich, sodium-ion batteries (SIBs) have become a hot topic of concern for many researchers. However, although SIBs share similar working principles with LIBs, traditional electrodes that are effective in LIBs may not be suitable for SIBs because Na + Radius yes 1.34 times of Na + Insertion of Na usually leads to slow battery kinetics and severe capacity decay. Therefore, in order to alleviate the above-mentioned problems, a reversible Na + Advanced electrode materials are highly desirable.

[0003] Chalcogenides generally have better reversibility than oxides. Compared with metal-oxygen (MO) bonds, metal-sulfur / selenium (MS / Se) bonds are relatively weak, resulting in more favorable kinetics and higher first-cycle coulombic efficiency. In addition, carbonaceous materials are common electrode materials with enhanced conductivity and inhibitory effects. Their morphology engineering is very effective in promoting Na + When metal sulfide compounds with high specific surface area are combined with carbonaceous materials, the ion diffusion pathway can be drastically shortened and highly accessible channels can be created at the interface, which is beneficial to surface redox pseudocapacitance and interfacial intercalation pseudocapacitance. The intercalation pseudocapacitance performs Faraday storage mechanism, which involves the insertion / extraction of ions and has the same time scale as redox pseudocapacitance.

[0004] Therefore, it is expected that based on the combination of metal sulfur compounds and carbonaceous materials, an electrode material with higher conductivity and rate performance, which can prolong the service life of sodium ion batteries (SIBs) can be explored. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material and its preparation method. Not only is the preparation method simple and easy to control, but the prepared composite material can also improve the conductivity, rate performance and service life of the sodium ion battery.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for preparing a CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material comprises the following steps:

[0008] Step 1, adding 1-2 mmol CuCl2·2H2O and 3-5 mmol thioacetamide to 40-60 mL deionized water, and ultrasonically dispersing to obtain a mixed solution A;

[0009] Step 2: adding 0.5-2 mmol of melamine to the mixed solution A and stirring thoroughly to obtain a uniform mixed solution B;

[0010] Step 3: Place the mixed solution B in a hydrothermal reactor, fully react at 160-200°C, and dry to obtain CuS x @Melamine precursor;

[0011] Step 4: CuS x @Melamine precursor was placed in a reactor, and under an argon protective atmosphere, the temperature was raised from room temperature to 400-440°C at a heating rate of 2°C / min and kept warm. After cooling to room temperature, CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material was obtained.

[0012] Furthermore, the stirring time in step 2 is 0.5h.

[0013] Furthermore, the reaction time in step 3 is 8 to 12 hours.

[0014] Furthermore, the drying in step 3 is performed in an oven at 60° C. for 8 hours.

[0015] Furthermore, the holding time in step 4 is 2 to 4 hours.

[0016] A CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material.

[0017] Compared with the prior art, the present invention has the following technical effects:

[0018] CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery anode material is prepared by a simple hydrothermal method and in-situ carbonization method, and a CuSx@nitrogen-doped carbon composite material with a hollow structure is constructed. The hollow structure reduces the transmission distance of ions / electrons, improves reaction kinetics and active material utilization; and the hollow structure, due to its large specific surface area, produces abundant active sites, which can store more active materials, thereby alleviating the volume change during the insertion and extraction of large sodium ions; in addition, the in-situ derived nitrogen-doped carbon improves the conductivity of the composite material, improves the rate performance, and also enhances the structural stability and prolongs the cycle life. It can be seen that the present invention not only has a simple preparation method, is easy to control, has a high reproducibility and is environmentally friendly, but also the synthesized CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery anode material has a large specific surface area, improves the conductivity and rate performance of the sodium ion battery, and prolongs the service life of the sodium ion battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the XRD pattern of the CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material prepared in Example 6 of the present invention;

[0020] Figure 2 This is a SEM image of the CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material prepared in Example 6 of the present invention;

[0021] Figure 3 TEM image of the CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material prepared in Example 6 of the present invention;

[0022] Figure 4 This is a cycle curve diagram of the CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material prepared in Example 6 of the present invention. DETAILED DESCRIPTION

[0023] The specific contents of the present invention are further explained in detail below with reference to the embodiments.

[0024] Example 1

[0025] Step 1, add 1 mmol of CuCl2·2H2O and 3 mmol of thioacetamide to 40 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0026] Step 2: Add 0.5 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0027] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 160°C for 8 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0028] Step 4: CuS x @The melamine precursor was placed in a reactor, and under an argon protective atmosphere, the temperature was raised to 400°C at a heating rate of 2°C / min, and calcined for 2 hours. After cooling, CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material was obtained.

[0029] Example 2

[0030] Step 1, add 2 mmol of CuCl2·2H2O and 5 mmol of thioacetamide to 60 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0031] Step 2: Add 2 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0032] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 200°C for 12 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0033] Step 4: CuS x The melamine precursor was placed in a reactor and heated to 440°C at a heating rate of 2°C / min under an argon protective atmosphere. The mixture was kept warm and calcined for 2 hours. After cooling to room temperature, the CuSx@ nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0034] Example 3

[0035] Step 1, add 1 mmol of CuCl2·2H2O and 3 mmol of thioacetamide to 40 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0036] Step 2: Add 0.5 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0037] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 160°C for 8 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0038] Step 4: CuS xThe @melamine precursor was placed in a reactor and heated to 410°C at a heating rate of 2°C / min under an argon protective atmosphere. It was kept warm and calcined for 3 hours. After cooling to room temperature, CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0039] Example 4

[0040] Step 1, add 2 mmol of CuCl2·2H2O and 5 mmol of thioacetamide to 60 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0041] Step 2: Add 2 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0042] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 160°C for 12 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0043] Step 4: CuS x The @melamine precursor was placed in a reactor and heated to 430°C at a heating rate of 2°C / min under an argon protective atmosphere. It was kept warm and calcined for 3 hours. After cooling to room temperature, CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0044] Example 5

[0045] Step 1, add 1 mmol of CuCl2·2H2O and 3 mmol of thioacetamide to 40 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0046] Step 2: Add 0.5 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0047] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 180°C for 8 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0048] Step 4: CuS x The @melamine precursor was placed in a reactor and heated to 400°C at a heating rate of 2°C / min under an argon protective atmosphere. It was kept warm and calcined for 4 hours. After cooling to room temperature, the CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0049] Example 6

[0050] Step 1: Add 1.5 mmol of CuCl2·2H2O and 4 mmol of thioacetamide to 50 mL of deionized water and perform sonication until dispersed to obtain a mixed solution A.

[0051] Step 2: Add 1 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0052] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 180°C for 10 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0053] Step 4: CuS x The @melamine precursor was placed in a reactor and heated to 420°C at a heating rate of 2°C / min under an argon protective atmosphere. It was kept warm and calcined for 2 hours. After cooling to room temperature, CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0054] Example 7

[0055] Step 1, add 2 mmol of CuCl2·2H2O and 5 mmol of thioacetamide to 60 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0056] Step 2: Add 2 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0057] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 170°C for 9 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0058] Step 4: CuS x The @melamine precursor was placed in a reactor and heated to 440°C at a heating rate of 2°C / min under an argon protective atmosphere. It was kept warm and calcined for 4 hours. After cooling to room temperature, CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0059] Example 8

[0060] Step 1, add 1 mmol of CuCl2·2H2O and 3 mmol of thioacetamide to 40 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0061] Step 2: Add 0.5 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0062] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 200°C for 8 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0063] Step 4: CuS x The @melamine precursor was placed in a reactor and heated to 400°C at a heating rate of 2°C / min under an argon protective atmosphere. It was kept warm and calcined for 2 hours. After cooling to room temperature, the CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0064] Example 9

[0065] Step 1, add 2 mmol of CuCl2·2H2O and 5 mmol of thioacetamide to 60 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0066] Step 2: Add 2 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0067] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 190°C for 11 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0068] Step 4: CuS x The melamine precursor was placed in a reactor and heated to 440°C at a heating rate of 2°C / min under an argon protective atmosphere. The mixture was kept warm and calcined for 2 hours. After cooling to room temperature, the CuSx@ nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0069] Example 10

[0070] Step 1: Add 1.5 mmol of CuCl2·2H2O and 3 mmol of thioacetamide to 40 mL of deionized water and perform sonication until dispersed to obtain a mixed solution A.

[0071] Step 2: Add 1.25 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0072] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 160°C for 8 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0073] Step 4: CuS xThe @melamine precursor was placed in a reactor and heated to 400°C at a heating rate of 2°C / min under an argon protective atmosphere. It was kept warm and calcined for 2 hours. After cooling to room temperature, the CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0074] Example 11

[0075] Step 1, add 2 mmol of CuCl2·2H2O and 4 mmol of thioacetamide to 60 mL of deionized water, and sonicate until dispersed to obtain a mixed solution A;

[0076] Step 2: Add 1.5 mmol of melamine to the mixed solution A and stir for 0.5 h to obtain a uniform mixed solution B;

[0077] Step 3: Place the mixed solution B in a 100 mL hydrothermal reactor, react at a hydrothermal temperature of 200°C for 12 hours, and dry in an oven at 60°C for 8 hours to obtain CuS x @Melamine precursor;

[0078] Step 4: CuS x The @melamine precursor was placed in a reactor and heated to 440°C at a heating rate of 2°C / min under an argon protective atmosphere. It was kept warm and calcined for 4 hours. After cooling to room temperature, CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material was obtained.

[0079] from Figure 1 It can be seen that the XRD diffraction peaks of the prepared sample correspond one to one with the diffraction peaks of CuS, proving that the synthesized product is CuS.

[0080] from Figure 2 It can be seen that the prepared sample presents a hollow tubular structure, which increases the specific surface area of ​​the composite material, increases the reaction active sites, and is beneficial to improving the performance of the material's sodium ion battery.

[0081] from Figure 3 It can be seen that the prepared sample is hollow and has a large number of pore structures on the surface, and the performance of sodium ion batteries can be further improved through structural adjustment.

[0082] from Figure 4 It can be seen that the cycle performance of the prepared sample is very good, and it still maintains 330mAg after 220 cycles at a current density of 5A / g. -1 This provides a simple strategy for achieving good cycling anode materials for sodium-ion batteries.

Claims

1. A method for preparing a CuSx@ nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material, characterized in that: The steps include: Step 1, adding 1-2 mmol CuCl2·2H2O and 3-5 mmol thioacetamide to 40-60 mL deionized water, and ultrasonically dispersing to obtain a mixed solution A; Step 2: adding 0.5-2 mmol of melamine to the mixed solution A and stirring thoroughly to obtain a uniform mixed solution B; Step 3: Place the mixed solution B in a hydrothermal reactor, heat at 160-200°C, allow to react fully, and dry to obtain CuS x @Melamine precursor; Step 4: CuS x @Melamine precursor was placed in a reactor, and under an argon protective atmosphere, the temperature was raised from room temperature to 400-440°C at a heating rate of 2°C / min and kept warm. After cooling to room temperature, CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material was obtained.

2. The method for preparing the CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material according to claim 1, characterized in that: The stirring time in step 2 is 0.5 h.

3. The method for preparing the CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material according to claim 1, characterized in that: The reaction time in step 3 is 8 to 12 hours.

4. The method for preparing the CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material according to claim 1, characterized in that: The drying in step 3 is performed in an oven at 60° C. for 8 h.

5. The method for preparing the CuSx@nitrogen-doped carbon hollow nanorod structure sodium ion battery negative electrode material according to claim 1, characterized in that: The holding time in step 4 is 2 to 4 hours.

6. A CuSx@nitrogen-doped carbon hollow nanorod structured sodium ion battery negative electrode material prepared by the method according to any one of claims 1 to 5.

Images