Copper sulfide nanotube material with multistage hollow structure, preparation method of copper sulfide nanotube material and lithium ion battery negative pole piece

Abstract

The invention discloses a copper sulfide nanotube material with a multistage hollow structure, a preparation method of the copper sulfide nanotube material and a lithium ion battery negative pole piece, and belongs to the technical field of organic and inorganic hybrid functional nano materials. Thiourea and copper chloride are used as raw materials, a spontaneous coordination reaction is carried out in a solvent at room temperature to obtain an organic-inorganic hybridized copper-thiourea nanorod with a rectangular side surface, and then the copper-thiourea nanorod and soluble sulfur salt are subjected to anion exchange to obtain the copper sulfide nanotube material with a multistage hollow structure. According to the method for preparing the copper sulfide nanotube material, provided by the invention, the aim of quickly preparing a large number of copper sulfide nanotube materials with multi-stage hollow structures at medium and low temperatures is fulfilled by utilizing organic-inorganic hybrid coordination rapid prototyping, performing subsequent anion exchange and adjusting the phase structure and composition of a product as rare earth elements and noble metals are not needed in the process; the preparation method is environment-friendly, pollution-free and low in cost, and raw materials are easy to obtain.

Description

Technical Field

[0001] The present invention relates to the technical field of organic-inorganic hybrid functional nanomaterials, and particularly relates to a copper sulfide nanotube material with a hierarchical hollow structure, a preparation method thereof, and a negative electrode sheet for a lithium-ion battery. Background Art

[0002] With the development of science and technology, portable electronic products and wearable electronic devices have been widely used in modern society. Among the components of these electronic products, the energy storage system and the battery system have increasingly become important factors restricting the further lightening, miniaturization, and long-lasting battery life of the devices.

[0003] Traditional means of transportation use fossil fuels as energy sources, which will lead to huge environmental problems and unsustainable development of energy. The key to solving these problems lies in the development of high-performance electrode materials. Lithium-ion batteries are recognized as one of the high-performance batteries that can best meet the requirements of sustainable development in future society due to their advantages of large working voltage window, high specific capacity, good safety, no memory effect, small self-discharge, and no environmental pollution. Currently, the main negative electrode material system of lithium-ion batteries is graphite. Although graphite is inexpensive and has excellent performance, it is limited by its relatively low theoretical lithium storage capacity (372 mAh·g -1 ), and it is no longer possible to significantly increase the capacity, and it is gradually difficult to meet the market's demand for higher-capacity lithium batteries.

[0004] Electrode materials are one of the important factors determining electrochemical performance. Exploring suitable positive and negative electrode materials has become the key to achieving efficient electrochemical energy storage. The design of nanostructured electrode materials is one of the effective ways to obtain good electrochemical performance. Among them, copper sulfide is an important transition metal sulfide compound. Due to its high conductivity and high capacitance, it has great application prospects in energy storage such as sodium-ion batteries, lithium-ion batteries, and supercapacitors; copper sulfide also has the advantages of low price and rich materials; as a typical p-type semiconductor material, CuS has a large number of holes in its structure, which is conducive to the transmission of electrons, and can be used as a carrier to realize the uniform dispersion of active substances, increasing the density of active sites; in addition, CuS has a metal-like conductivity (10 -3 S / cm), and has a good redox reaction with polysulfide electrolytes. All these reasons make it one of the preferred electrode materials and have become a research hotspot.

[0005] However, the existing preparation methods of copper sulfide, such as sublimating sulfur blowing on copper metal at high temperature, electrochemical deposition method, and hydrothermal method under high temperature and high pressure, usually have problems such as uncontrollable preparation conditions, environmental unfriendliness during the preparation process, or excessive energy consumption. Moreover, the obtained copper sulfide is difficult to reach the theoretical capacity to provide electrochemical performance. In addition, the prepared copper sulfide is usually amorphous large particles or thick sheet bodies with a smooth surface, and it is difficult to customize the nano-morphology beneficial to the electrochemical surface interface at a relatively low synthesis temperature. Summary of the Invention

[0006] Aiming at the deficiencies of the above-mentioned existing technologies, the present invention provides a copper sulfide nanotube material with a multi-stage hollow structure, its preparation method, and a negative electrode sheet for a lithium-ion battery. The present invention uses thiourea and copper chloride as raw materials, and through a spontaneous coordination reaction in a solvent, a copper-thiourea nanorod with an organic-inorganic hybrid and a rectangular side surface is obtained. Then, the copper-thiourea nanorod is subjected to an anion exchange with a soluble sulfur salt to obtain a copper sulfide nanotube with a multi-stage hollow structure and copper sulfide nanosheets on the surface. The copper sulfide nanotube material with a multi-stage hollow structure obtained by the method of the present invention can be used as an electrochemical electrode material, effectively solving the technical defect of low theoretical capacity of the current carbon-based materials as electrode materials. At the same time, a method for simply, greenly synthesizing, easily modifying, widely applying, and suitable for large-scale production of a copper sulfide nanotube material with a multi-stage hollow structure is provided.

[0007] The first object of the present invention is to protect a preparation method of a copper sulfide nanotube material with a multi-stage hollow structure, including the following steps:

[0008] Using thiourea (Tu) and copper chloride as raw materials, through a spontaneous coordination reaction, and rapid shaping by the coupling coordination reaction of copper ions and thiourea, an organic-inorganic hybrid copper-thiourea nanorod with a rectangular side surface is obtained. The copper-thiourea nanorod is an organic-inorganic hybrid ligand of copper chloride and thiourea, with the chemical formula of 0.5H2O·Cu(Tu)Cl, in which copper and chlorine form coordination bonds with thiourea in a hydrated ionic state.

[0009] Mix the copper-thiourea nanorod with a soluble sulfur salt, and adopt the anion exchange method. Through the anion exchange of the S 2- with (Tu)Cl - group, a copper sulfide nanotube material with a multi-stage hollow structure is obtained.

[0010] Preferably, the molar ratio of thiourea to copper chloride is 1:0.2 - 1. Below this ratio, a copper sulfide nanotube with a multi-stage structure surface will not be obtained.

[0011] Preferably, the molar ratio of copper chloride to the soluble sulfur salt is 1:0.3 - 1.2. Below this ratio, a copper sulfide nanotube with a multi-stage structure surface will not be obtained.

[0012] Preferably, the molar ratio of thiourea to soluble sulfide salt is 1:0.1 - 1.

[0013] Preferably, the conditions for the spontaneous coordination reaction are: reacting at 20°C - 100°C for 1 h - 72 h. In principle, in the presence of chloride ions, copper ions can form spontaneous coordination with thiourea molecules without additional heating, forming "Cu - Tu - Cl" from "Cl - Cu - Cl, Tu". However, the kinetics of this metal - organic coordination is very slow. Therefore, the synthesis time is shortened by increasing the ambient temperature. However, under the thermodynamic conditions of 25 ± 5°C, this reaction can still proceed. When the temperature or time is below this range, the reaction will not occur; when the temperature or time is above this range, copper sulfide nanotubes with a multi - level structure surface will not be obtained.

[0014] Preferably, thiourea and copper chloride are co - dispersed in a solvent for the spontaneous coordination reaction. The solvent is selected from one or a mixture of more of pure water, ethanol, and ethylene glycol, and the volume ratio of pure water to ethanol and / or ethylene glycol is 1:0.1 - 10. The role of ethanol and ethylene glycol is to provide different liquid - phase forces to control the reaction process.

[0015] Preferably, the conditions for the anion - exchange method are: standing at room temperature for 12 h - 72 h.

[0016] Preferably, the solute of the soluble sulfide salt aqueous solution is selected from one of sodium sulfide, potassium sulfide, calcium sulfide, barium sulfide, ammonium sulfide, or the hydrates of the above salts.

[0017] Preferably, copper chloride is selected from anhydrous copper chloride or copper chloride dihydrate.

[0018] The second object of the present invention is to protect the copper sulfide nanotube material with a multi - level hollow structure prepared by the above - mentioned preparation method. The copper sulfide nanotube material with a multi - level hollow structure is a copper sulfide nanotube with a multi - level hollow structure having copper sulfide nanosheets on its surface.

[0019] Preferably, the theoretical capacity of the copper sulfide nanotube material with a multi - level hollow structure is 560 mAh·g -1 , and the theoretical capacity is significantly higher than that of graphite.

[0020] The third object of the present invention is to protect the application of the copper sulfide nanotube material with a multi - level hollow structure in the preparation of anode materials for lithium - ion batteries.

[0021] The fourth object of the present invention is to protect the anode electrode sheet for a lithium - ion battery, which is composed of a copper sulfide nanotube material with a multi - level hollow structure, a conductive agent, a binder, and a current collector.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] 1. The present invention provides a method for preparing copper sulfide nanotube materials with a multi-level hollow structure. First, copper-thiourea nanorods with a rectangular side surface of an organic-inorganic hybrid are spontaneously formed by the coordination of thiourea and copper chloride. Then, anion exchange is carried out between the copper-thiourea nanorods and a soluble sulfur salt to obtain copper sulfide nanotube materials with copper sulfide nanosheets on the surface. The principle of the method of the present invention is as follows: rapid shaping is achieved by the coupling coordination reaction of copper ions and the organic matter thiourea, and then the phase structure and composition of the product are adjusted through subsequent ion exchange reactions, so that Cu + is oxidized to Cu 2+ , and a transformation from an organic-inorganic hybrid phase to an inorganic phase occurs, thereby obtaining hollow copper sulfide nanotube materials with a copper sulfide flake structure on the surface. Moreover, since rare earth elements and precious metals are not required in the preparation process, the purpose of rapidly preparing a large amount of copper sulfide nanotube materials with a multi-level hollow structure at medium and low temperatures is realized.

[0024] In the copper sulfide nanotube materials with a multi-level hollow structure obtained by the method of the present invention, due to the surface of the one-dimensional hollow structure containing nanostructured thin flake units, a large specific surface area, and a stable framework structure, unique electrochemical energy storage advantages are exhibited. Among them, the nanostructured units reduce the ion / electron transport distance, improve the reaction kinetics and the utilization rate of active substances; the large specific surface area provides abundant electrochemically active sites; the stable framework structure can store more active substances and relieve the structural stress during the electrochemical reaction process. Therefore, by constructing a reasonable one-dimensional hollow structure, copper sulfide nanotube materials with a multi-level hollow structure and excellent electrochemical performance are obtained.

[0025] 2. The copper sulfide nanotube materials with a multi-level hollow structure of the present invention have the characteristic of a favorable surface between the electrode and the electrolyte. The hierarchical copper sulfide nanotubes can provide a better confinement effect for the electrochemical surface interface, thereby promoting the kinetics of the electrode reaction.

[0026] 3. The results show that the copper sulfide nanotube materials with a multi-level hollow structure obtained by the present invention not only have a high theoretical capacity (560 mAh·g -1) , but also have the characteristics of a high density of active sites and excellent conductivity, which is beneficial to improving the application performance of batteries and capacitors. It can be used as a negative electrode material to replace graphite and overcome the technical defect that graphite is limited by a relatively low theoretical lithium storage capacity.

[0027] 4. The present invention realizes the purpose of rapidly preparing a large amount of copper sulfide nanotube materials with a multi-level hollow structure at medium and low temperatures. Moreover, the preparation process is environmentally friendly, pollution-free, low-cost, and the raw materials are easy to obtain. Description of the Drawings

[0028] Figure 1 TEM image of the copper sulfide nanotube material with a multi - level hollow structure in Example 1.

[0029] Figure 2 XRD pattern of the copper sulfide nanotube material with a multi - level hollow structure in Example 1.

[0030] Figure 3 Raman spectrum of the copper sulfide nanotube material with a multi - level hollow structure in Example 1.

[0031] Figure 4 Cyclic voltammogram of the copper sulfide nanotube material with a multi - level hollow structure in Example 1.

[0032] Figure 5 Electrochemical impedance spectrum of the copper sulfide nanotube material with a multi - level hollow structure in Example 1. Detailed implementation manners

[0033] In order to enable those skilled in the art to better understand and implement the technical solutions of the present invention, the present invention will be further described below in conjunction with specific embodiments and drawings, but the embodiments cited are not intended to limit the present invention. The following test methods and detection methods are all conventional methods unless otherwise specified; the reagents and raw materials are all commercially available unless otherwise specified.

[0034] Considering the low theoretical lithium storage capacity of graphite in the prior art and the advantages of copper sulfide, the purpose of the present invention is to provide a copper sulfide material with a high theoretical capacity to replace graphite for use.

[0035] Considering that the preparation methods of copper sulfide in the prior art usually have problems such as uncontrollable preparation conditions, environmental unfriendliness during the preparation process or excessive energy consumption, the present invention provides a new preparation method for a copper sulfide nanotube material with a multi - level hollow structure. The method of the present invention can achieve the rapid preparation of a copper sulfide nanotube material with a multi - level hollow structure only at medium and low temperatures, and the solvent is one or a mixture of deionized water, ethanol, and ethylene glycol, overcoming the problems of uncontrollable conditions, environmental unfriendliness during the preparation process or excessive energy consumption of the existing methods.

[0036] The theoretical capacity of the copper sulfide nanotube material with a multi - level hollow structure obtained by the method of the present invention is 560 mAh·g -1 , which can provide excellent electrochemical performance and overcomes the problem of low theoretical capacity of copper sulfide prepared by existing methods.

[0037] The copper sulfide nanotube material with a multi - level hollow structure obtained by the method of the present invention is a copper sulfide nanotube with a multi - level hollow structure having copper sulfide nanosheets on the surface, which has a surface - interface beneficial to electrochemistry and overcomes the defects existing in the conventional copper sulfide which is usually an amorphous large particle or thick sheet with a smooth surface.

[0038] The copper sulfide nanotube material with a multi - level hollow structure of the present invention is prepared according to the following steps: Dissolve thiourea and copper chloride in a solvent, carry out a spontaneous complexation reaction at 20 °C - 100 °C for 1 h - 72 h, obtain copper - thiourea nanorods by suction filtration, mix the copper - thiourea nanorods with an aqueous solution of soluble sulfide salt, stand at room temperature for 12 h - 72 h, and carry out an anion - exchange reaction. Finally, obtain the copper sulfide nanotube material with a multi - level hollow structure through centrifugation and freeze - drying.

[0039] The technical solution of the present invention will be further explained and illustrated by the following examples, as shown specifically below:

[0040] Example 1

[0041] A preparation method of a copper sulfide nanotube material with a multi - level hollow structure, comprising the following steps:

[0042] S1. Disperse 0.17 g of copper chloride dihydrate and 0.2 g of thiourea in 40 mL and 10 mL of pure water respectively, then mix the two, heat to 100 °C and keep warm for 1 h to carry out a spontaneous complexation reaction, and then obtain copper - thiourea nanorods through suction filtration. Among them, the molar ratio of thiourea to copper chloride dihydrate is 1:0.38.

[0043] S2. Disperse the copper - thiourea nanorods into a 30 - mL suspension, add 0.14 g of sodium sulfide nonahydrate to the suspension, place it at room temperature (25 °C) for 48 h, then centrifuge at 5000 r.p.m for 5 min, and freeze - dry the precipitate to obtain the copper sulfide nanotube material with a multi - level hollow structure. Among them, the molar ratio of thiourea to soluble sulfide salt is 1:0.22.

[0044] Example 2

[0045] A preparation method of a copper sulfide nanotube material with a multi - level hollow structure, comprising the following steps:

[0046] S1. Disperse 0.17 g of copper chloride dihydrate and 0.17 g of thiourea in 40 mL and 10 mL of pure water respectively, then mix the two, heat to 90 °C and keep warm for 1 h to carry out a spontaneous complexation reaction, and then obtain copper - thiourea nanorods through suction filtration. Among them, the molar ratio of thiourea to copper chloride dihydrate is about 1:0.45.

[0047] S2. Disperse the copper-thiourea nanorods into a 30 mL suspension, add 0.43 g of sodium sulfide nonahydrate to the suspension, place it at room temperature (25 °C) for 48 h, then centrifuge at 5000 r.p.m for 5 min, and freeze-dry the precipitate to obtain a copper sulfide nanotube material with a hierarchical hollow structure. Among them, the molar ratio of thiourea to soluble sulfide is 1:0.8.

[0048] Example 3

[0049] A method for preparing a copper sulfide nanotube material with a hierarchical hollow structure, comprising the following steps:

[0050] S1. Disperse 0.17 g of copper(II) chloride dihydrate and 0.2 g of thiourea in 40 mL and 10 mL of pure water respectively, then mix the two, heat to 90 °C and keep warm for 1 h to carry out a spontaneous coordination reaction, and then obtain copper-thiourea nanorods by suction filtration. Among them, the molar ratio of thiourea to copper(II) chloride dihydrate is about 1:0.45.

[0051] S2. Disperse the copper-thiourea nanorods into a 30 mL suspension, add 0.1 g of sodium sulfide nonahydrate to the suspension, place it at room temperature (25 °C) for 48 h, then centrifuge at 5000 r.p.m for 5 min, and freeze-dry the precipitate to obtain a copper sulfide nanotube material with a hierarchical hollow structure. Among them, the molar ratio of thiourea to soluble sulfide is 1:0.16.

[0052] Example 4

[0053] A method for preparing a copper sulfide nanotube material with a hierarchical hollow structure, comprising the following steps:

[0054] S1. Disperse 0.17 g of copper(II) chloride dihydrate and 0.2 g of thiourea in 40 mL and 10 mL of a solvent respectively. The solvent consists of ethanol and water with a volume ratio of 1:4. Then mix the two, heat to 90 °C and keep warm for 1 h to carry out a spontaneous coordination reaction, and then obtain copper-thiourea nanorods by suction filtration. Among them, the molar ratio of thiourea to copper(II) chloride dihydrate is about 1:0.45.

[0055] S2. Disperse the copper-thiourea nanorods into a 30 mL suspension, add 0.12 g of sodium sulfide nonahydrate to the suspension, place it at room temperature (25 °C) for 48 h, then centrifuge at 5000 r.p.m for 5 min, and freeze-dry the precipitate to obtain a copper sulfide nanotube material with a hierarchical hollow structure. Among them, the molar ratio of thiourea to soluble sulfide is 1:0.83.

[0056] Example 5

[0057] A method for preparing a copper sulfide nanotube material with a hierarchical hollow structure, comprising the following steps:

[0058] S1. Disperse 0.12 g of copper chloride dihydrate and 0.2 g of thiourea in 40 mL and 10 mL of ethylene glycol respectively, then mix the two, heat to 70 °C and keep warm for 1 h to carry out a spontaneous coordination reaction, and then obtain copper-thiourea nanorods by suction filtration. Among them, the molar ratio of thiourea to copper chloride dihydrate is about 1:0.27.

[0059] S2. Disperse the copper-thiourea nanorods into a 30 mL suspension, add 0.12 g of sodium sulfide nonahydrate to the suspension, place it at room temperature (25 °C) for 48 h, then centrifuge at 5000 r.p.m for 5 min, and freeze-dry the precipitate to obtain a copper sulfide nanotube material with a hierarchical hollow structure. Among them, the molar ratio of thiourea to soluble sulfur salt is 1:0.83.

[0060] Example 6

[0061] A preparation method of a copper sulfide nanotube material with a hierarchical hollow structure, comprising the following steps:

[0062] S1. Disperse 0.17 g of copper chloride dihydrate and 0.1 g of thiourea in 40 mL and 10 mL of ethylene glycol respectively, then mix the two, heat to 50 °C and keep warm for 1 h to carry out a spontaneous coordination reaction, and then obtain copper-thiourea nanorods by suction filtration. Among them, the molar ratio of thiourea to copper chloride dihydrate is about 1:0.2.

[0063] S2. Disperse the copper-thiourea nanorods into a 30 mL suspension, add 0.06 g of sodium sulfide nonahydrate to the suspension, place it at room temperature (25 °C) for 72 h, then centrifuge at 5000 r.p.m for 5 min, and freeze-dry the precipitate to obtain a copper sulfide nanotube material with a hierarchical hollow structure. Among them, the molar ratio of thiourea to soluble sulfur salt is 1:0.1.

[0064] Example 7

[0065] A preparation method of a copper sulfide nanotube material with a hierarchical hollow structure, comprising the following steps:

[0066] S1. Disperse 0.17 g of copper chloride dihydrate and 0.526 g of thiourea in 40 mL and 10 mL of ethylene glycol respectively, then mix the two, stir at 20 °C for 72 h to carry out a spontaneous coordination reaction, and then obtain copper-thiourea nanorods by suction filtration. Among them, the molar ratio of thiourea to copper chloride dihydrate is about 1:1.

[0067] S2. Disperse the copper-thiourea nanorods into a 30 mL suspension, add 0.63 g of sodium sulfide nonahydrate to the suspension, place it at room temperature (25 °C) for 48 h, then centrifuge at 5000 r.p.m for 5 min, and freeze-dry the precipitate to obtain a copper sulfide nanotube material with a hierarchical hollow structure. Among them, the molar ratio of thiourea to soluble sulfur salt is 1:1.

[0068] In Examples 1 to 7 of the present invention, copper sulfide nanotube materials with a high theoretical capacity and a multi-stage hollow structure were all prepared. Taking the copper sulfide nanotube materials with a multi-stage hollow structure in Example 1 as an example for research, the specific research methods and results are as follows:

[0069] According to Figure 1 the TEM data shown, the copper sulfide nanotube materials with a multi-stage hollow structure are overall a hollow multi-stage nanotube structure, with uniformly arranged nanosheets on the surface, and the tube diameter distribution is 100 nm to 500 nm.

[0070] According to Figure 2 the XRD data shown, the copper sulfide nanotube materials with a multi-stage hollow structure belong to the copper sulfide phase of the hexagonal crystal system, corresponding to PDF card No. 06-0464. The product is pure and there are no other impurities.

[0071] According to Figure 3 the Raman spectrum shown, the main chemical bond in the copper sulfide nanotube materials with a multi-stage hollow structure is the Cu-S bond, indicating that the product is copper sulfide, which is consistent with Figure 2 the conclusion given.

[0072] Taking the copper sulfide nanotube materials with a multi-stage hollow structure prepared in Example 1 as an example, the electrochemical performance was studied, with the aim of using the low-cost copper sulfide nanotube materials with a multi-stage hollow structure of the present invention to replace the existing graphite anode materials. The specific research methods and results are as follows:

[0073] Using Ag / AgCl as the reference electrode and a graphite rod as the counter electrode, a three-electrode system was formed with the working electrode. One end of the reference electrode, the counter electrode, and the working electrode was jointly placed in a 1 mol / L NaCl solution, and the other end was jointly electrically connected to an electrochemical workstation for electrochemical performance testing.

[0074] Preparation of the working electrode: The copper sulfide nanotube materials with a multi-stage hollow structure in Example 1, activated carbon, and PVDF were dispersed in NMP according to a mass ratio of 8:1:1 to prepare a uniform and flowing viscous slurry, and the total powder mass of the three was 10 mg. It was coated on a square graphite paper with a side length of 2 cm and dried in a vacuum drying oven at 80 °C for 12 h to obtain the working electrode.

[0075] Figure 4 The cyclic voltammetry curve of -1 was measured in the above three-electrode system, with a scan rate of 100 mV s -1 , and the voltage window was 0 V to 1.6 V. The results show that the hollow copper sulfide nanotube materials with a multi-stage structure have a high specific capacitance, and the electrochemical behavior on the electrode surface is mainly pseudocapacitive.

[0076] Figure 5 The electrochemical impedance spectrum was measured in the above three - electrode system. The test frequency range was from 0.01 Hz to 100 kHz, and the AC amplitude was 10 mV. The results show that the obtained hollow copper sulfide nanotubes with a multi - level structure have a small system resistance and mass transfer resistance, thus exhibiting excellent electrochemical energy storage performance.

[0077] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and its equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. Preparation method of copper sulfide nanotube material with multi-stage hollow structure, characterized in that, It includes the following steps: Dissolve thiourea and copper chloride in a solvent. Through a spontaneous coordination reaction, utilize the coupling coordination reaction between copper ions and thiourea for rapid prototyping to obtain an organic-inorganic hybrid copper-thiourea nanorod with a rectangular side surface: Mix the copper-thiourea nanorod with an aqueous solution of soluble sulfide salt, and adopt the anion exchange method to obtain a copper sulfide nanotube material with a hierarchical hollow structure.

2. The preparation method of the copper sulfide nanotube material with a multi-stage hollow structure according to claim 1, characterized in that, The molar ratio of thiourea to copper chloride is 1:0.2 - 1.

3. The preparation method of the copper sulfide nanotube material with a multi-stage hollow structure according to claim 1, characterized in that, The molar ratio of copper chloride to soluble sulfide salt is 1:0.3 - 1.

2.

4. The preparation method of the copper sulfide nanotube material with a multi-level hollow structure according to claim 1, characterized in that, The molar ratio of thiourea to soluble sulfide salt is 1:0.1 - 1.

5. The preparation method of the copper sulfide nanotube material with a multi-stage hollow structure according to claim 1, characterized in that, The conditions for the spontaneous coordination reaction are: reacting at 20°C - 100°C for 1h - 72h.

6. The preparation method of the copper sulfide nanotube material with a multi-level hollow structure according to claim 1, characterized in that, The solvent is selected from one or a mixture of deionized water, ethanol, and ethylene glycol, and the volume ratio of pure water to ethanol and / or ethylene glycol is 1:0.1 - 10.

7. The preparation method of the copper sulfide nanotube material with a multi-stage hollow structure according to claim 1, characterized in that, The conditions for the anion exchange method are: standing at room temperature for 12h - 72h.

8. A copper sulfide nanotube material with a hierarchical hollow structure prepared by the preparation method according to any one of claims 1 to 7, characterized in that, The copper sulfide nanotube material with a hierarchical hollow structure is a copper sulfide nanotube with a hierarchical hollow structure and copper sulfide nanosheets on the surface.

9. The copper sulfide nanotube material with a multi-stage hollow structure according to claim 8, characterized in that, The theoretical capacity of the copper sulfide nanotube material with a multi-level hollow structure is 560 mAh·g -1 .

10. A negative electrode sheet of a lithium-ion battery, characterized in that, It is composed of the copper sulfide nanotube material with a hierarchical hollow structure according to claim 8, a conductive agent, a binder, and a current collector.

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