WXC / W / CNT composite material, preparation method and application
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- WUHAN UNIV OF SCI & TECH
- Filing Date
- 2021-12-27
- Publication Date
- 2026-06-19
Smart Images
Figure CN114497517B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of lithium-ion battery electrode materials, specifically relating to a W X C / W / CNT composite materials, preparation methods and applications. Background Technology
[0002] Lithium-ion batteries have advantages such as high voltage, high energy density, and low pollution, and have been widely used in electronic products and electric vehicles.
[0003] Currently, graphite remains the mainstream anode material for commercial lithium-ion batteries. However, with economic and social development, the relatively low theoretical specific capacity and energy density of graphite are insufficient to meet the needs of existing portable devices such as smartphones and laptops, as well as electric vehicles. Therefore, there is a need to design a W... X This paper addresses the aforementioned issues by describing C / W / CNT composite materials, their preparation methods, and their applications. Summary of the Invention
[0004] To address the problems mentioned in the background section, this invention provides a W X The preparation method of C / W / CNT composite material has the advantages of good stability of tungsten carbide, abundant active sites and good conductivity of carbon nanotubes, which can meet the needs of existing portable devices such as smartphones and laptops as well as electric vehicles.
[0005] Another object of the present invention is to provide a W X Applications of C / W / CNT composite materials.
[0006] To achieve the above objectives, the present invention provides the following technical solution: a W X The preparation method of C / W / CNT composite material includes the following steps:
[0007] S1: Dissolve methyl orange and ferric chloride in deionized water, stir thoroughly, add pyrrole, stir thoroughly in a low-temperature reactor, and obtain pyrrole tubes;
[0008] S2: Pyrrole tube and hexadecyltrimethylammonium bromide are added to an ethanol solution and sonicated. Ammonium tungstate is dissolved in deionized water and then added to the above ethanol solution. Dopamine and ammonia are added in sequence and stirred thoroughly to obtain a precursor powder containing tungsten source and carbon source.
[0009] S3: After thoroughly grinding the precursor powder, place it in a tube furnace and perform high-temperature heat treatment under argon protection to obtain W. X C / W / CNT composite material.
[0010] Furthermore, in step S1 of this invention, the mass ratio of methyl orange, ferric chloride and pyrrole is 1:10-11:5.
[0011] Furthermore, in step S1 of this invention, the volume of deionized water is 200 ml.
[0012] Furthermore, in step S1 of this invention, the stirring time is 2 hours, the temperature of the low-temperature reactor is 5-15°C, and the stirring time is 20-28 hours.
[0013] Furthermore, in step S2 of this invention, the mass ratio of pyrrole, hexadecyltrimethylammonium bromide, ammonium tungstate, and dopamine is 1:1:4:2.
[0014] Furthermore, in step S2 of this invention, the volume of the ethanol solution is 40 ml, the volume of the deionized water is 20 ml, and the volume of the ammonia solution is 0.2 ml.
[0015] Furthermore, in step S2 of this invention, the ultrasonic time is 60-120 min and the stirring time is 2-3 h.
[0016] Furthermore, in step S3 of this invention, the heat treatment temperature is 800-1000℃, the heating rate is 10℃ / min, and the holding time is 2-3h.
[0017] A method according to the W X The preparation method of C / W / CNT composite material prepared W X C / W / CNT composite material.
[0018] A W X The preparation method of C / W / CNT composite material prepared W X Applications of C / W / CNT composite materials: Primarily used in electrochemical energy storage.
[0019] Compared with the prior art, the beneficial effects of the present invention are:
[0020] 1. This invention uses hexadecyltrimethylammonium bromide to treat pyrrole tubes, resulting in abundant cations on the surface of the pyrrole tubes. Subsequently, dopamine polymerization is used to tightly adsorb tungstate anions onto the surface of the pyrrole tubes. After high-temperature treatment, a composite material of tungsten carbide / metallic tungsten uniformly coated carbon nanotubes is obtained. This solves the problems of low and uneven tungsten carbide / metallic tungsten coating, easy detachment, and insufficient contact with the carbon substrate, and can meet the needs of existing portable devices such as smartphones and laptops, as well as electric vehicles.
[0021] 2. The introduction of tungsten metal in this invention can improve the electronic structure of tungsten carbide, and a unique synergistic effect is produced between the two. In addition, tungsten carbide itself has extremely high stability, so when it is applied to lithium-ion battery anode materials, it has a high capacity retention rate during high current density cycling.
[0022] 3. The carbon nanotubes prepared by the present invention using pyrrole as a carbon source have good electrical conductivity and serve as a carrier for tungsten carbide and metallic tungsten, which greatly improves the electron transfer efficiency. Attached Figure Description
[0023] Figure 1 XRD patterns of samples prepared for this invention;
[0024] Figure 2 Thermogravimetric curve of the sample prepared in this invention under an oxygen atmosphere;
[0025] Figure 3 This is a SEM image of a sample prepared according to an embodiment of the present invention;
[0026] Figure 4 SEM image of a sample prepared according to another embodiment of the present invention;
[0027] Figure 5 This is a graph showing the long-cycle performance of samples prepared according to one embodiment and another embodiment of the present invention. Detailed Implementation
[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0029] Example 1
[0030] Please see Figure 1-5 The present invention provides the following technical solution: a W X The preparation method of C / W / CNT composite material includes the following steps:
[0031] S1: Dissolve methyl orange and ferric chloride in 200 ml of deionized water at a mass ratio of 1:10, stir for 2 h, add pyrrole at a mass ratio of 1:5 with methyl orange, stir in a low temperature reactor at 10 °C for 24 h to obtain pyrrole tubes.
[0032] S2: Pyrrole tube and hexadecyltrimethylammonium bromide were added to 40 ml of ethanol solution at a mass ratio of 1:1 and sonicated for 120 min. Ammonium tungstate at a mass ratio of 1:4 with pyrrole tube was dissolved in 20 ml of deionized water and then added to the above ethanol solution. Dopamine at a mass ratio of 1:2 with pyrrole tube and 0.2 ml of ammonia water at a volume ratio of 100:1 with deionized water were added in sequence. The mixture was stirred for 2 h to obtain a precursor powder containing tungsten source and carbon source.
[0033] S3: After thoroughly grinding the precursor powder, place it in a tube furnace and heat it to 800℃ at a heating rate of 10℃ / min under argon protection. Hold the temperature for 3 hours and then cool it with the furnace to obtain W. X C / W / CNT composite material.
[0034] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X C / W / CNT composite material.
[0035] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X Applications of C / W / CNT composite materials: Primarily used in electrochemical energy storage.
[0036] Example 2
[0037] Please see Figure 1-5 The present invention provides the following technical solution: a W X The preparation method of C / W / CNT composite material includes the following steps:
[0038] S1: Dissolve methyl orange and ferric chloride in 200 ml of deionized water at a mass ratio of 1:11, stir for 2 h, add pyrrole at a mass ratio of 1:5 with methyl orange, stir in a low temperature reactor at 5 °C for 20 h to obtain pyrrole tubes;
[0039] S2: Pyrrole tube and hexadecyltrimethylammonium bromide were added to 40 ml of ethanol solution at a mass ratio of 1:1 and sonicated for 120 min. Ammonium tungstate at a mass ratio of 1:4 with pyrrole tube was dissolved in 20 ml of deionized water and then added to the above ethanol solution. Dopamine at a mass ratio of 1:2 with pyrrole tube and 0.2 ml of ammonia water at a volume ratio of 100:1 with deionized water were added in sequence. The mixture was stirred for 2 h to obtain a precursor powder containing tungsten source and carbon source.
[0040] S3: After thoroughly grinding the precursor powder, place it in a tube furnace and heat it to 800℃ at a heating rate of 10℃ / min under argon protection. Hold the temperature for 3 hours and then cool it with the furnace to obtain W. X C / W / CNT composite material.
[0041] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X C / W / CNT composite material.
[0042] A method based on the above W X The preparation method of C / W / CNT composite material prepared W XApplications of C / W / CNT composite materials: Primarily used in electrochemical energy storage.
[0043] Example 3
[0044] Please see Figure 1-5 The present invention provides the following technical solution: a W X The preparation method of C / W / CNT composite material includes the following steps:
[0045] S1: Dissolve methyl orange and ferric chloride in 200 ml of deionized water at a mass ratio of 1:10, stir for 2 h, add pyrrole at a mass ratio of 1:5 with methyl orange, stir in a low temperature reactor at 15 °C for 28 h to obtain pyrrole tubes.
[0046] S2: Pyrrole tube and hexadecyltrimethylammonium bromide were added to 40 ml of ethanol solution at a mass ratio of 1:1 and sonicated for 60 min. Ammonium tungstate at a mass ratio of 1:4 with pyrrole tube was dissolved in 20 ml of deionized water and then added to the above ethanol solution. Dopamine at a mass ratio of 1:2 with pyrrole tube and 0.2 ml of ammonia water at a volume ratio of 100:1 with deionized water were added in sequence. The mixture was stirred for 3 h to obtain a precursor powder containing tungsten source and carbon source.
[0047] S3: After thoroughly grinding the precursor powder, place it in a tube furnace and heat it to 900℃ at a heating rate of 10℃ / min under argon protection. Hold the temperature for 2 hours and then cool it with the furnace to obtain W. X C / W / CNT composite material.
[0048] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X C / W / CNT composite material.
[0049] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X Applications of C / W / CNT composite materials: Primarily used in electrochemical energy storage.
[0050] Instruction manual attached Figure 1 The image shows the XRD pattern of the prepared sample. It can be seen that the diffraction peaks of W, WC, and W₂C are sharp and correspond one-to-one with the crystal planes of the standard card. The broad peak at approximately 26° corresponds to the amorphous carbon peak. Therefore, this example successfully prepared W… X C / W / CNT composite material.
[0051] Example 4
[0052] Please see Figure 1-5The present invention provides the following technical solution: a W X The preparation method of C / W / CNT composite material includes the following steps:
[0053] S1: Dissolve methyl orange and ferric chloride in 200 ml of deionized water at a mass ratio of 1:11, stir for 2 h, add pyrrole at a mass ratio of 1:5 with methyl orange, stir in a low temperature reactor at 10 °C for 24 h to obtain pyrrole tubes.
[0054] S2: Pyrrole tube and hexadecyltrimethylammonium bromide were added to 40 ml of ethanol solution at a mass ratio of 1:1 and sonicated for 90 min. Ammonium tungstate at a mass ratio of 1:4 with pyrrole tube was dissolved in 20 ml of deionized water and then added to the above ethanol solution. Dopamine at a mass ratio of 1:2 with pyrrole tube and 0.2 ml of ammonia water at a volume ratio of 100:1 with deionized water were added in sequence. The mixture was stirred for 2 h to obtain a precursor powder containing tungsten source and carbon source.
[0055] S3: After thoroughly grinding the precursor powder, place it in a tube furnace and heat it to 900℃ at a heating rate of 10℃ / min under argon protection. Hold the temperature for 2 hours and then cool it with the furnace to obtain W. X C / W / CNT composite material.
[0056] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X C / W / CNT composite material.
[0057] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X Applications of C / W / CNT composite materials: Primarily used in electrochemical energy storage.
[0058] Instruction manual attached Figure 2 The figure shows the thermogravimetric curve of the prepared sample under an oxygen atmosphere. Since tungsten carbide and metallic tungsten are converted into tungsten trioxide (WO3) at high temperature, and carbon nanotubes are completely ablated, the loading of tungsten carbide and metallic tungsten can be determined from this figure to be between 45.04% and 48.14%.
[0059] Example 5
[0060] Please see Figure 1-5 The present invention provides the following technical solution: a W X The preparation method of C / W / CNT composite material includes the following steps:
[0061] S1: Dissolve methyl orange and ferric chloride in 200 ml of deionized water at a mass ratio of 1:11, stir for 2 h, add pyrrole at a mass ratio of 1:5 with methyl orange, stir in a low temperature reactor at 10 °C for 24 h to obtain pyrrole tubes.
[0062] S2: Pyrrole tube and hexadecyltrimethylammonium bromide were added to 40 ml of ethanol solution at a mass ratio of 1:1 and sonicated for 90 min. Ammonium tungstate at a mass ratio of 1:4 with pyrrole tube was dissolved in 20 ml of deionized water and then added to the above ethanol solution. Dopamine at a mass ratio of 1:2 with pyrrole tube and 0.2 ml of ammonia water at a volume ratio of 100:1 with deionized water were added in sequence. The mixture was stirred for 2 h to obtain a precursor powder containing tungsten source and carbon source.
[0063] S3: After thoroughly grinding the precursor powder, place it in a tube furnace and heat it to 1000℃ at a heating rate of 10℃ / min under argon protection. Hold the temperature for 2 hours and then cool it with the furnace to obtain W. X C / W / CNT composite material.
[0064] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X C / W / CNT composite material.
[0065] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X Applications of C / W / CNT composite materials: Primarily used in electrochemical energy storage.
[0066] Example 6
[0067] Please see Figure 1-5 The present invention provides the following technical solution: a W X The preparation method of C / W / CNT composite material includes the following steps:
[0068] S1: Dissolve methyl orange and ferric chloride in 200 ml of deionized water at a mass ratio of 1:10, stir for 2 h, add pyrrole at a mass ratio of 1:5 with methyl orange, stir in a low temperature reactor at 15 °C for 28 h to obtain pyrrole tubes.
[0069] S2: Pyrrole tube and hexadecyltrimethylammonium bromide were added to 40 ml of ethanol solution at a mass ratio of 1:1 and sonicated for 60 min. Ammonium tungstate at a mass ratio of 1:4 with pyrrole tube was dissolved in 20 ml of deionized water and then added to the above ethanol solution. Dopamine at a mass ratio of 1:2 with pyrrole tube and 0.2 ml of ammonia water at a volume ratio of 100:1 with deionized water were added in sequence. The mixture was stirred for 3 h to obtain a precursor powder containing tungsten source and carbon source.
[0070] S3: After thoroughly grinding the precursor powder, place it in a tube furnace and heat it to 1000℃ at a heating rate of 10℃ / min under argon protection. Hold the temperature for 2 hours and then cool it with the furnace to obtain W. X C / W / CNT composite material.
[0071] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X C / W / CNT composite material.
[0072] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X Applications of C / W / CNT composite materials: Primarily used in electrochemical energy storage.
[0073] Example 7
[0074] Please see Figure 1-5 The present invention provides the following technical solution: a W X The preparation method of C / W / CNT composite material includes the following steps:
[0075] S1: Dissolve methyl orange and ferric chloride in 200 ml of deionized water at a mass ratio of 1:11, stir for 2 h, add pyrrole at a mass ratio of 1:5 with methyl orange, stir in a low temperature reactor at 10 °C for 24 h to obtain pyrrole tubes.
[0076] S2: Pyrrole tube and hexadecyltrimethylammonium bromide were added to 40 ml of ethanol solution at a mass ratio of 1:1 and sonicated for 60 min. Ammonium tungstate at a mass ratio of 1:4 with pyrrole tube was dissolved in 20 ml of deionized water and then added to the above ethanol solution. Dopamine at a mass ratio of 1:2 with pyrrole tube and 0.2 ml of ammonia water at a volume ratio of 100:1 with deionized water were added in sequence. The mixture was stirred for 3 h to obtain a precursor powder containing tungsten source and carbon source.
[0077] S3: After thoroughly grinding the precursor powder, place it in a tube furnace and heat it to 800℃ at a heating rate of 10℃ / min under argon protection. Hold the temperature for 2 hours and then cool it with the furnace to obtain W.X C / W / CNT composite material.
[0078] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X C / W / CNT composite material.
[0079] A method based on the above W X The preparation method of C / W / CNT composite material prepared W X Applications of C / W / CNT composite materials: Primarily used in electrochemical energy storage.
[0080] Instruction manual attached Figure 3 and 4 The images shown are SEM images of the carbon nanotubes prepared in Examples 3 and 7, respectively. Most of the carbon nanotubes prepared in Example 7 have very smooth surfaces, with only a small portion having tungsten carbide and metallic tungsten loaded on their surfaces. In contrast, the sample tubes prepared in Example 3 have very rough surfaces and larger diameters. (Refer to the accompanying manual for details.) Figure 1 The XRD results show that this embodiment successfully achieved uniform and tight coating of tungsten carbide and metallic tungsten on carbon nanotubes.
[0081] Instruction manual attached Figure 5 The graphs show the long-cycle performance of the samples prepared in Example 4 and Example 7. Under the test conditions of 5 A / g, after 1000 cycles, the specific capacity of the sample prepared in Example 3 is 176 mAh / g, while the specific capacity of the sample prepared in Example 7 is only 132 mAh / g. It can be seen that the uniform and tight coating of tungsten carbide and metallic tungsten on carbon nanotubes, as well as the synergistic effect between tungsten carbide and metallic tungsten, effectively improves the electrochemical performance of the battery under high current.
[0082] In summary, the prepared W X The C / W / CNT composite material achieves uniform coating of tungsten carbide and metallic tungsten on carbon nanotubes. The tight bonding between tungsten carbide and metallic tungsten and the carbon substrate gives the composite material the advantages of tungsten carbide's good stability and abundant active sites, as well as the excellent conductivity of carbon nanotubes. Using it as a negative electrode material for lithium-ion batteries can significantly improve the high-current cycling performance of the batteries.
[0083] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A W X A method for producing a C / W / CNT composite material, characterized by, Includes the following steps: S1: Dissolve methyl orange and ferric chloride in deionized water, stir thoroughly for 2 hours, add pyrrole, and stir thoroughly in a low-temperature reactor at 5-15℃ for 20-28 hours to obtain pyrrole tubes, wherein the mass ratio of methyl orange, ferric chloride and pyrrole is 1:10-11:5; S2: Pyrrole tubes and hexadecyltrimethylammonium bromide are added to an ethanol solution and sonicated. Ammonium tungstate is dissolved in deionized water and then added to the above ethanol solution. Dopamine and ammonia are then added in sequence and stirred thoroughly to obtain a precursor powder containing tungsten and carbon sources. The mass ratio of pyrrole tubes, hexadecyltrimethylammonium bromide, ammonium tungstate and dopamine is 1:1:4:
2. S3: After thoroughly grinding the precursor powder, place it in a tube furnace and, under argon protection, heat it to 800-1000℃ at a heating rate of 10℃ / min for high-temperature heat treatment, holding it at that temperature for 2-3 hours to obtain W. X C / W / CNT composite material, wherein W X C / W / CNT composite materials are used in lithium-ion battery anode materials.
2. A W X The method for preparing C / W / CNT composite material is characterized by comprising the following steps: In step S1, the volume of deionized water is 200 ml.
3. A W X The method for preparing a C / W / CNT composite material is characterized by comprising the following steps: In step S2, the volume of the ethanol solution is 40 ml, the volume of the deionized water is 20 ml, and the volume of the ammonia solution is 0.2 ml.
4. A W according to claim 3 X The method for preparing C / W / CNT composite materials is characterized by: In step S2, the ultrasonic time is 60-120 min and the stirring time is 2-3 h.
5. A W X Method of making C / W / CNT composite X Applications of C / W / CNT composite: In electrochemical energy storage.