CN112678806B - Carbon @ SiO x /C @ carbon nanotube composite material and preparation method thereof - Google Patents
Carbon @ SiO x /C @ carbon nanotube composite material and preparation method thereof Download PDFInfo
- Publication number
- CN112678806B CN112678806B CN202011557828.9A CN202011557828A CN112678806B CN 112678806 B CN112678806 B CN 112678806B CN 202011557828 A CN202011557828 A CN 202011557828A CN 112678806 B CN112678806 B CN 112678806B
- Authority
- CN
- China
- Prior art keywords
- carbon
- carbon nanotube
- sio
- composite material
- nanotube composite
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention provides carbon @ SiO x The preparation method of the/C @ carbon nanotube composite material comprises the following specific steps: s1, dispersing a silicon source and a carbon nano tube in a mixed solvent, adding ammonia water, and centrifugally drying to obtain an organic silicon @ carbon nano tube composite material; s2, placing the organic silicon @ carbon nanotube composite material in a tubular furnace, carrying out primary carbonization in a protective atmosphere, then introducing organic gas for secondary carbonization, and finally cooling to room temperature to obtain carbon @ SiO x the/C @ carbon nanotube composite material. The invention utilizes a sol-gel method to grow organic silicon on a carbon nano tube in situ, and the carbon @ SiO is prepared after two times of high-temperature carbonization x the/C @ carbon nanotube composite material comprises an inner carbon nanotube, an outer carbon shell and small-particle SiO sandwiched between the carbon shell and the carbon nanotube x The layer/C has the synergistic effect of the three-layer structure, so that the volume expansion of the composite material is reduced, and the electronic conductivity is improved.
Description
Technical Field
The invention relates to the technical field of electrochemical energy storage, in particular to carbon @ SiO x a/C @ carbon nano tube composite material and a preparation method thereof.
Background
Novel device pair represented by portable electronic device and electric vehicle and capable of rapidly charging high energy densityLithium ion battery technology has placed significant demands. However, most of the lithium ion batteries currently use graphite materials as negative electrodes, and the theoretical specific capacity of the graphite negative electrode is only 372mAh g -1 The development of lithium ion batteries is severely limited. In contrast, the theoretical specific capacity of the silicon Si negative electrode is up to 4200mAh g -1 And the potential of the deintercalated lithium is comparable to that of graphite, the Si-based negative electrode is one of the best materials to replace the graphite negative electrode in the development process of a battery with high energy and high power density. However, the silicon-based negative electrode material has a large expansion/contraction in the cycle process, which easily causes pulverization and falling of the material structure, and seriously hinders the development of industrialization.
Silicon-oxygen cathode material SiO x (0<x<2) The lithium silicate and the lithium oxide substances generated after the material is firstly embedded with lithium can play a certain buffering role on volume expansion, have relatively stable cycle performance and attract the wide attention of researchers; however, the problems of volume expansion and low electronic conductance still exist, and how to reduce the volume expansion and improve the electronic conductance is a problem to be solved urgently at present.
Disclosure of Invention
In view of the above, the present invention is directed to a carbon @ SiO x A/C @ carbon nanotube composite material for improving SiO content and its preparation method x The material has conductivity when replacing graphite cathode and being used in lithium ion battery, and enlarges SiO x The industrialization advantage of the material.
In order to achieve the purpose, the technical scheme of the invention is realized as follows: carbon @ SiO x The preparation method of the/C @ carbon nanotube composite material comprises the following specific steps:
s1, dispersing a silicon source and carbon nanotube particles in a mixed solvent, adding ammonia water, and centrifugally drying to obtain an organic silicon @ carbon nanotube composite material;
s2, placing the organic silicon @ carbon nanotube composite material in a tubular furnace, carrying out primary carbonization in a protective atmosphere, then introducing organic gas for secondary carbonization, and finally cooling to room temperature to obtain carbon @ SiO x the/C @ carbon nanotube composite material.
Optionally, the silicon source comprises one or more of vinyltrimethoxysilane, vinyltriethoxysilane, ethynyltriethoxysilane, ethynyltrimethoxysilane, triaminopropyltrimethoxysilane, and triaminopropyltriethoxysilane;
the carbon nano tube particles comprise one or more of single-walled carbon nano tube dispersion liquid, multi-walled carbon nano tube dispersion liquid, single-walled carbon nano tube powder and multi-walled carbon nano tube powder;
the mixed solvent comprises at least one of deionized water, ethanol, ethylene glycol, n-butanol and isopropanol.
Optionally, in S1, a volume/mass ratio of the silicon source to the carbon nanotube particles is 0.001 to 100.
Optionally, the concentration of ammonia is (0.01-25) wt.%.
Alternatively, the ammonia is added at a rate of (0.01-20) seconds per drop.
Optionally, in S2, the primary carbonization is performed under a protective atmosphere, specifically: under the protection atmosphere, the reaction temperature is controlled to be 100-1500 ℃, the reaction time is 3-12 h, and primary carbonization is carried out.
Optionally, in S2, the introducing organic gas for secondary carbonization specifically includes: introducing ethylene gas, acetylene gas, benzene steam or toluene steam, controlling the reaction temperature to be 500-1200 ℃ and the reaction time to be 10min-10h, and carrying out secondary carbonization.
Compared with the prior art, the carbon @ SiO provided by the invention x The preparation method of the/C @ carbon nanotube composite material has the following advantages:
the method comprises the steps of growing organic silicon on a carbon nano tube in situ by using a sol-gel method to form a shell layer or a beaded shell layer conformal with the carbon nano tube; after twice high-temperature carbonization, the prepared carbon @ SiO x the/C @ carbon nanotube composite material comprises an inner carbon nanotube, an outer carbon shell and small-particle SiO (silicon dioxide) particles clamped between the carbon shell and the carbon nanotube x The layer/C and the three-layer structure have synergistic effect, so that the volume expansion of the composite material is reduced, and the electronic conductivity is improved, so that carbon @ SiO is added x Application of/C @ carbon nanotube composite material in lithium ionWhen the material is used as a cell cathode material, the material shows excellent electrochemical performance, and provides a new technology for the development of high-performance cathode materials. In addition, the preparation method has the advantages of simple operation process, safe reaction, low equipment cost and high experimental repeatability, and is beneficial to industrial large-scale production and popularization.
The other purpose of the invention is to provide carbon @ SiO x The composite material of/C @ carbon nanotube for solving SiO x The material has expansion and conductivity problems when used in lithium ion batteries as a replacement for graphite negative electrodes.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
carbon @ SiO x the/C @ carbon nanotube composite material adopts the carbon @ SiO x Preparation method of/C @ carbon nanotube composite material, and carbon @ SiO x the/C @ carbon nanotube composite material comprises a carbon nanotube and a shell layer loaded on the surface of the carbon nanotube, wherein the shell layer is in a bead string shape or is matched with the shape of the carbon nanotube.
Optionally, the shell layer comprises particulate SiO in contact with the carbon nanotubes x a/C layer and a coating layer coated on the SiO x A carbon shell on the surface of the C layer.
Optionally, the shell layer has a thickness of (1-300) nm.
The carbon @ SiO x the/C @ carbon nanotube composite material and the carbon @ SiO x Compared with the prior art, the preparation method of the/C @ carbon nanotube composite material has the same advantages, and the detailed description is omitted.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief description will be given below to the drawings required for the description of the embodiments or the prior art, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.
FIG. 1 is a schematic representation of carbon @ SiO in accordance with an embodiment of the present invention x Synthesis of/C @ carbon nanotube composite materialA schematic view of the principle;
FIG. 2 shows carbon @ SiO obtained in example 1 x SEM image of/C @ carbon nanotube composite material;
FIG. 3 is a SiO solid obtained in comparative example of example 1 x SEM image of/C composite material;
FIG. 4 shows carbon @ SiO solid obtained in example 1 x the/C @ carbon nanotube composite material is 0.1A g -1 A lower charge-discharge curve;
FIG. 5 shows the carbon @ SiOx/C @ carbon nanotube composite obtained in example 1 and SiO in comparative example x The material/C is 0.5A g -1 Comparative plot of cycle performance at bottom;
FIG. 6 shows carbon @ SiO solid obtained in example 1 x /C @ carbon nanotube composite and comparative SiO x A comparison graph of the rate performance of the material;
FIG. 7 shows carbon @ SiO obtained in example 1 x /C @ carbon nanotube composite and comparative SiO x Impedance test comparison graph of the/C material;
FIG. 8 shows carbon @ SiO solid obtained in example 2 x SEM image of/C @ carbon nanotube composite material;
FIG. 9 shows carbon @ SiO solid obtained in example 3 x SEM picture of/C @ carbon nanotube composite;
FIG. 10 is a schematic representation of carbon @ SiO in accordance with an embodiment of the present invention x Flow schematic diagram of a preparation method of/C @ carbon nanotube composite material.
Description of the reference numerals:
1-carbon nanotube, 2-organosilicon, 3-SiO x Layer C, 4-carbon shell.
Detailed Description
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.
Carbon nanotubes have unique characteristics due to their one-dimensional carbon tube structure, and the loading materials on carbon nanotubes have been widely used in the preparation of various electrode materials. The silicon-oxygen cathode material is characterized in thatThe expansion is lower than that of nano silicon carbon, the nano silicon carbon has relatively better cycle performance, and is a hotspot of industrial research, the composition with a conductive carbon material is a great trend at present, and carbon can be used as a medium for buffering volume expansion and can also play a role of a conductive agent. However, siO has not been obtained yet x the/C homogeneous mixed material is compounded with a carbon nanotube material and developed to be used as a lithium ion battery cathode material.
To solve the above problem, an embodiment of the present invention provides a carbon @ SiO film as shown in fig. 1 and 10 x The preparation method of the/C @ carbon nanotube composite material comprises the following specific steps:
s1, dispersing a silicon source and carbon nanotube particles in a mixed solvent, adding ammonia water, and centrifugally drying to obtain an organic silicon @ carbon nanotube composite material;
s2, placing the organic silicon @ carbon nanotube composite material in a tubular furnace, carrying out primary carbonization in a protective atmosphere, then introducing organic gas for secondary carbonization, and finally cooling to room temperature to obtain carbon @ SiO x the/C @ carbon nanotube composite material.
According to the embodiment of the invention, the used silicon source is hydrolyzed into silanol in ammonia water, the silanol is adsorbed on the carbon nano tube 1 with negative electricity on the surface through the action of hydrogen bonds, and the silanol causes organosilicon to grow on the carbon nano tube 1 through polycondensation reaction to form an organosilicon @ carbon nano tube composite material; then, the organic silicon is carbonized to form SiO through high-temperature carbonization and carbon coating x And C to obtain carbon @ SiO x The composite material of/C @ carbon nano tube. The preparation method provided by the embodiment of the invention is simple and safe in reaction, does not need the dangerous and complicated operation step of reducing silicon dioxide by using a metal reducing agent, and the prepared carbon @ SiO x the/C @ carbon nanotube composite material comprises an inner carbon nanotube 1, an outer carbon shell 4 and small-particle SiO (silicon dioxide) particles clamped between the carbon shell 4 and the carbon nanotube 1 x the/C layer 3, the integration of the three carbon structures can greatly improve the electronic conductivity of the composite material, so that carbon @ SiO x When the/C @ carbon nanotube composite material is applied to the negative electrode material of the lithium ion battery, the excellent electrochemical performance is shown, and the development of the high-performance negative electrode material is realizedProvides a new technology and expands SiO x The industrialization advantage of the material.
Specifically, in step S1, the silicon source includes one or more of vinyltrimethoxysilane, vinyltriethoxysilane, ethynyltriethoxysilane, ethynyltrimethoxysilane, triaminopropyltrimethoxysilane, and triaminopropyltriethoxysilane; the carbon nanotube particles include one or more of a single-walled carbon nanotube dispersion, a multi-walled carbon nanotube dispersion, a single-walled carbon nanotube powder, and a multi-walled carbon nanotube powder. The carbon nano tube is of a one-dimensional structure, is beneficial to shortening the transmission path of lithium ions, and is convenient to combine with organic silicon by adopting a dispersion liquid or powder structure. Wherein the volume/mass ratio (mL/mg) of the silicon source to the carbon nanotube particles is 0.001-100.
The mixed solvent comprises at least one of deionized water, ethanol, ethylene glycol, n-butanol and isopropanol. Wherein, when two solvents are adopted, the volume ratio of any two solvents is (1-99) to (99-1).
Compared with the prior art, the preparation method provided by the embodiment of the invention has the advantages that the raw materials are cheap, for example, dangerous and expensive silicon sources such as silane gas are not needed, and the production cost is effectively reduced.
In addition, since the organosilicon 2 grows on the carbon nano tube 1 through the polycondensation reaction between the silanols, the thickness of the organosilicon can be adjusted by changing the adding amount of the silicon source; after the organic silicon 1 is carbonized, siO can be formed x With an atomically homogeneous mixture of C, the roughness of the surface being related to the rate of polycondensation between silanols, i.e. carbonized SiO x The roughness of the/C layer 3 can be adjusted by changing the concentration of the aqueous ammonia and the dropping speed. In the present embodiment, preferably, the concentration of aqueous ammonia is (0.01-25) wt.%; the rate of addition of ammonia was (0.01-20) seconds per drop.
In the step S2, carrying out primary carbonization under a protective atmosphere, specifically: under the protective atmosphere, the reaction temperature is controlled to be 100-1500 ℃, the reaction time is 3-12 h, and primary carbonization is carried out. After primary carbonization, the organosilicon forms SiO x Atomically homogeneous mixture of SiO with C x A layer C.
In step S2And introducing organic gas for secondary carbonization, specifically comprising the following steps: introducing ethylene gas, acetylene gas, benzene steam or toluene steam, controlling the reaction temperature to be 500-1200 ℃ and the reaction time to be 10min-10h, and carrying out secondary carbonization. Through secondary carbonization, siO is convenient to be formed x The surface of the/C layer forms a carbon shell which can inhibit the expansion of silicon and maintain the stability of the material structure.
The embodiment of the invention provides carbon @ SiO x The preparation method of the/C @ carbon nano tube composite material comprises the steps of growing organic silicon 2 on a carbon nano tube 1 in situ by a sol-gel method, and carbonizing the organic silicon at high temperature for two times to prepare carbon @ SiO x the/C @ carbon nanotube composite material comprises an inner carbon nanotube 1, an outer carbon shell 4 and small-particle SiO (silicon dioxide) particles clamped between the carbon shell 4 and the carbon nanotube 1 x the/C layer 3 has the synergistic effect of the three-layer structure, so that the volume expansion of the composite material is reduced, and the electronic conductivity is improved.
With reference to fig. 1 and 2, an embodiment of the present invention further provides carbon @ SiO x a/C @ carbon nanotube composite material, said carbon @ SiO x the/C @ carbon nanotube composite material adopts the above weight of carbon @ SiO x The preparation method of the/C @ carbon nanotube composite material. The carbon @ SiO x the/C @ carbon nanotube composite material comprises a carbon nanotube 1 and a shell layer loaded on the surface of the carbon nanotube 1, wherein the shell layer is in a bead string shape or is matched with the shape of the carbon nanotube. Wherein the shell layer comprises granular SiO contacting with the carbon nanotube 1 x Layer 3/C and SiO x A carbon shell 4 on the surface of the C layer 3.
Thus, siO x The electronic conductivity of the composite material can be improved by three carbon structures, so that the composite material has good electrochemical performance. Further, the shell layer has a thickness of (1-300) nm.
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The following examples are examples of experimental procedures not specified under specific conditions, generally according to the conditions recommended by the manufacturer. Unless otherwise indicated, percentages and parts are by mass.
Example 1
This example provides a carbon @ SiO x The preparation method of the/C @ carbon nanotube composite material comprises the following specific steps:
1) Adding 1mL of vinyltrimethoxysilane and 1.5mL of single-walled carbon nanotube aqueous solution (3 mg/mL) into 150mL of distilled water, namely the volume/mass ratio of the silicon source to the carbon nanotube is 0.22, then dropwise adding 25wt.% of ammonia aqueous solution at the speed of 0.01 second/drop, stirring for 12 hours, centrifuging, washing and drying to obtain the organic silicon @ carbon nanotube composite material.
2) Carrying out primary carbonization on the dried organic silicon @ carbon nanotube composite material in a tubular furnace under the protection of argon, wherein the carbonization time is 4 hours, the carbonization temperature is 800 ℃, then introducing acetylene gas/argon mixed gas for 30 minutes for secondary carbonization, the carbonization time is 30 minutes, the carbonization temperature is 800 ℃, and cooling to room temperature to obtain carbon @ SiO x the/C @ carbon nanotube composite material.
FIG. 2 is the carbon @ SiO film obtained in example 1 x SEM image of/C @ carbon nanotube composite material, wherein a) is a scale of 1 μm and b) is a scale of 100nm, and it can be seen from FIG. 2 that the whole composite material still maintains the one-dimensional continuous linear structure of carbon nanotubes and SiO x the/C material grows on the carbon tube in a bead shape, and the maximum spherical diameter is about 100nm.
Example 1 comparative example:
1) Adding 1.0mL of vinyl trimethoxy silane into 200mL of distilled water, quickly adding 25.0wt.% of ammonia water solution, stirring for 12 hours, centrifuging, washing and drying to obtain the organic silicon sphere material.
2) Carbonizing the dried organic silicon ball material in a tubular furnace for one time under the protection of argon at the carbonization temperature of 800 ℃ for 4 hours to obtain SiO after cooling to room temperature x a/C composite material.
FIG. 3 shows SiO obtained in comparative example of example 1 x SEM image of/C composite material, as can be seen from FIG. 3, siO shown in comparative example x the/C composite material is in a monodisperse spherical shape, and the particle size is about 300nm.
Example 1 carbon @ SiO x /C @ carbon nanotube composite and comparative exampleThe resulting SiO x The application of the/C composite material as the negative electrode material of the lithium ion battery is as follows:
the preparation process of the electrode slice respectively adopts carbon @ SiO x /C @ carbon nanotube composite material and SiO x the/C composite material is used as an active material, acetylene black is used as a conductive agent, and sodium alginate is used as a binder. Fully mixing the three components according to the mass ratio of 7. And coating the surface of the copper foil, and drying at 70 ℃ to obtain the negative electrode plate. Wherein the electrolyte is 1mol/L LiPF 6 Per EC (lithium ion battery electrolyte) + DMC (dimethyl carbonate) (volume ratio 1) and 5% fec (fluoroethylene carbonate), the separator being a glass fiber GF/a film, CR2016 coin cells were made for testing the half-cell charging performance of the materials.
FIG. 4 shows carbon @ SiO obtained in example 1 x the/C @ carbon nanotube composite material is 0.1A g -1 The following charge-discharge curves, as can be seen from FIG. 4, carbon @ SiO x the/C @ carbon nanotube composite material is 0.1A g -1 The specific capacity of the next first circulation discharge is 1553mAh g -1 。
FIG. 5 shows carbon @ SiO solid obtained in example 1 x /C @ carbon nanotube composite and comparative SiO x the/C material was at 0.5 Ag -1 The cycle performance of carbon @ SiO, as can be seen from FIG. 5 x the/C @ carbon nanotube composite material is 0.5A g -1 After 500 cycles of lower circulation, the capacity is 573.9mAh g -1 Decaying to 479.45mAh g -1 The capacity retention rate is 83.5%; while SiO of the comparative example x After 500 cycles of circulation of the/C composite material, the capacity is 642.9 mAh g -1 Decay to 406.13mAh g -1 And the capacity retention rate is only 63.2 percent, so that the carbon @ SiO prepared by the invention can be seen x the/C @ carbon nanotube composite material shows excellent cycle performance when being used as a lithium ion battery cathode material.
FIG. 6 shows carbon @ SiO obtained in example 1 x /C @ carbon nanotube composite and comparative SiO x Comparison graph of rate performance of/C material, as can be seen from FIG. 6, charging and discharging under large current, carbon @ SiO x SiO (silicon dioxide) with rapid charge/discharge advantage ratio of/C @ carbon nanotube composite material x Composite material/CThe material is more obvious, namely the carbon @ SiO prepared by the invention x the/C @ carbon nanotube composite material shows excellent rate capability when being used as a lithium ion battery cathode material, and explains carbon @ SiO to a certain extent x the/C @ carbon nanotube composite material has better quick charging capability.
FIG. 7 shows carbon @ SiO solid obtained in example 1 x /C @ carbon nanotube composite and comparative SiO x Comparative graph of impedance test for the/C material, as can be seen in FIG. 7, carbon @ SiO x The charge transfer resistance of the/C @ carbon nanotube composite material is smaller, and is consistent with the excellent quick charging capability of the battery under high current.
The above properties show that the carbon @ SiO prepared by the invention x the/C @ carbon nanotube composite material has excellent electrochemical performance and is a good lithium ion battery cathode material.
Example 2
This example differs from example 1 in that:
in the step 1), 0.3mL of vinyltrimethoxysilane and 2.0mL of a single-walled carbon nanotube aqueous solution (3 mg/mL) are added into 200mL of distilled water, namely the volume/mass ratio of the silicon source to the carbon nanotubes is 0.05, and 0.3wt.% of ammonia water is dropwise added at the speed of 5 seconds per drop;
in the step 2), the primary carbonization time is 5 hours, and the carbonization temperature is 800 ℃;
other parameters were the same as in example 1.
FIG. 8 is carbon @ SiO solid obtained in example 2 x SEM image of/C @ carbon nanotube composite material, wherein a) is a graph with a scale of 100nm, b) is a graph with a scale of 50nm, and as can be seen from FIG. 8, carbon @ SiO prepared in example 2 x The shape of the/C @ carbon nanotube composite material keeps a one-dimensional continuous linear structure of the carbon nanotube, the shell layer grows on the carbon nanotube in a conformal manner with the carbon nanotube, the overall diameter is about 35nm, and the surface is smooth, which indicates that the thickness and the surface roughness of the shell layer of the composite material can be adjusted by changing the adding amount of a silicon source and controlling the concentration and the dropping speed of ammonia water.
Example 3
This example differs from example 1 in that:
in the step 1), 0.2mL of vinyltrimethoxysilane and 1.5mL of a single-walled carbon nanotube aqueous solution (3 mg/mL) are added into 150mL of distilled water, namely the volume/mass ratio of the silicon source to the carbon nanotube is 0.04, and 0.3wt.% of ammonia water is dropwise added at the speed of 1 second/drop;
in the step 2), the carbonization time of the primary carbonization is 5 hours, the carbonization temperature is 900 ℃, the carbonization time of the secondary carbonization is 20 minutes, and the carbonization temperature is 900 ℃;
other parameters were the same as in example 1.
FIG. 9 is carbon @ SiO solid prepared in example 3 x SEM image of/C @ carbon nanotube composite material, wherein a) is a scale image of 100nm, b) is a scale image of 50nm, and as can be seen from FIG. 9, the carbon @ SiO prepared in example 3 x The shape of the/C @ carbon nanotube composite material keeps a one-dimensional continuous linear structure of the carbon nanotube, the shell layer grows on the carbon tube in a string shape, and the surface is rough, which shows that the thickness and the surface roughness of the shell layer of the composite material can be adjusted by changing the adding amount of a silicon source and controlling the concentration and the dropping speed of ammonia water.
Example 4
This example differs from example 1 in that:
in the step 1), 0.2mL of vinyltrimethoxysilane and 1.5mL of a multiwall carbon nanotube aqueous solution (3 mg/mL) are added into a mixed solution of 150mL of distilled water and 50mL of ethanol, namely the volume/mass ratio of a silicon source to the carbon nanotubes is 0.04, and 3wt.% of ammonia water is dropwise added at the speed of 1 second/drop;
in the step 2), the carbonization time of the primary carbonization is 5 hours, the carbonization temperature is 800 ℃, the carbonization time of the secondary carbonization is 5 minutes, and the carbonization temperature is 800 ℃;
other parameters were the same as in example 1.
Example 5
This example differs from example 1 in that:
in the step 1), 0.6mL of triaminopropyltrimethoxysilane and 2mL of multiwall carbon nanotube aqueous solution (2 mg/mL) are added into a mixed solution of 150mL of distilled water and 50mL of ethanol, namely the volume/mass ratio of a silicon source to carbon nanotubes is 0.15, and 2wt.% of ammonia water solution is dropwise added at the speed of 5 seconds per drop;
in the step 2), the carbonization time of the primary carbonization is 3 hours, the carbonization temperature is 1000 ℃, the carbonization time of the secondary carbonization is 60 minutes, and the carbonization temperature is 1000 ℃;
other parameters were the same as in example 1.
Example 6
The present example differs from example 1 in that:
in step 1), 0.4mL of triaminopropyltrimethoxysilane and 5mg of multiwalled carbon nanotubes were added to a water-ethanol mixed solution (water: the volume ratio of ethanol is 1: 1) Namely, the volume/mass ratio of the silicon source to the carbon nanotube is 0.08, and 2.5wt.% of ammonia water solution is dripped at the speed of 2 seconds/drip;
in the step 2), the carbonization time of the primary carbonization is 3 hours, the carbonization temperature is 1000 ℃, the carbonization time of the secondary carbonization is 10 minutes, and the carbonization temperature is 1000 ℃;
other parameters were the same as in example 1.
Example 7
This example differs from example 1 in that:
in step 1), 0.8mL of vinyltrimethoxysilane and 5mg of single-walled carbon nanotubes were added to a water-ethanol mixed solution (water: the volume ratio of the ethanol is 4: 1) Namely, the volume/mass ratio of the silicon source to the carbon nano tube is 0.16, and 25wt.% of ammonia water solution is dripped at the speed of 2 seconds per drip;
in the step 2), the carbonization time of the primary carbonization is 6 hours, the carbonization temperature is 900 ℃, the carbonization time of the secondary carbonization is 15 minutes, and the carbonization temperature is 900 ℃;
other parameters were the same as in example 1.
Example 8
The present example differs from example 1 in that:
in the step 1), 0.4mL of vinyltriethoxysilane and 0.4mL of multiwall carbon nanotube aqueous solution (10 mg/mL) are added into 100mL of distilled water, namely the volume/mass ratio of the silicon source to the carbon nanotube is 0.1, and 2wt.% of ammonia water is dropwise added at the speed of 20 seconds per drop;
in the step 2), the carbonization time of the primary carbonization is 6 hours, the carbonization temperature is 900 ℃, the carbonization time of the secondary carbonization is 10 minutes, and the carbonization temperature is 900 ℃;
other parameters were the same as in example 1.
Example 9
This example differs from example 1 in that:
in the step 1), 0.1mL of vinyltriethoxysilane and 0.5mL of single-walled carbon nanotube aqueous solution (4 mg/mL) are added into 100mL of distilled water, namely the volume/mass ratio of the silicon source to the carbon nanotube is 0.05, and 3wt.% of ammonia aqueous solution is dropwise added at the speed of 15 seconds/drop;
in the step 2), the carbonization time of the primary carbonization is 4 hours, the carbonization temperature is 800 ℃, the carbonization time of the secondary carbonization is 10 minutes, and the carbonization temperature is 800 ℃;
other parameters were the same as in example 1.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (7)
1. Carbon @ SiO x The preparation method of the/C @ carbon nanotube composite material is characterized by comprising the following specific steps of:
s1, dispersing a silicon source and carbon nano tube particles in a mixed solvent, adding ammonia water, and centrifugally drying to obtain an organic silicon @ carbon nano tube composite material; the silicon source comprises one or more of vinyl trimethoxy silane, vinyl triethoxy silane, ethynyl trimethoxy silane, triaminopropyl trimethoxy silane and triaminopropyl triethoxy silane; the carbon nano tube particles comprise one or more of single-walled carbon nano tube dispersion liquid, multi-walled carbon nano tube dispersion liquid, single-walled carbon nano tube powder and multi-walled carbon nano tube powder; the mixed solvent comprises at least one of deionized water, ethanol, ethylene glycol, n-butyl alcohol and isopropanol;
s2, placing the organic silicon @ carbon nanotube composite material in a tubular furnace, controlling the reaction temperature to be 100-1500 ℃ and the reaction time to be 3-12 h under the protective atmosphere, carrying out primary carbonization, then introducing ethylene gas, acetylene gas, benzene steam or toluene steam, controlling the reaction temperature to be 500-1200 ℃ and the reaction time to be 10min-10h, carrying out secondary carbonization, and finally cooling to room temperature to obtain carbon @ SiO x the/C @ carbon nanotube composite material.
2. The method according to claim 1, wherein a volume/mass ratio of the silicon source to the carbon nanotube particles in S1 is 0.001 to 100.
3. The method according to claim 1, wherein the concentration of the aqueous ammonia is (0.01-25) wt.%.
4. The method according to claim 3, wherein the ammonia water is added at a rate of (0.01-20) sec/drop.
5. Carbon @ SiO x A/C @ carbon nanotube composite material, characterized in that the carbon @ SiO of any one of the preceding claims 1 to 4 is used x Preparation method of/C @ carbon nanotube composite material, and carbon @ SiO x the/C @ carbon nanotube composite material comprises a carbon nanotube (1) and a shell layer loaded on the surface of the carbon nanotube (1), wherein the shell layer is in a bead string shape or is matched with the shape of the carbon nanotube (1).
6. Carbon @ SiO of claim 5 x the/C @ carbon nanotube composite material is characterized in that the shell layer comprises granular SiO contacting with the carbon nanotube (1) x a/C layer (3) and a coating layer coated on the SiO x A carbon shell (4) on the surface of the C layer (3).
7. Carbon @ SiO as in claim 6 x the/C @ carbon nanotube composite material is characterized in that the thickness of the shell layer is (1-300) nm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011557828.9A CN112678806B (en) | 2020-12-25 | 2020-12-25 | Carbon @ SiO x /C @ carbon nanotube composite material and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011557828.9A CN112678806B (en) | 2020-12-25 | 2020-12-25 | Carbon @ SiO x /C @ carbon nanotube composite material and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112678806A CN112678806A (en) | 2021-04-20 |
| CN112678806B true CN112678806B (en) | 2023-02-07 |
Family
ID=75453161
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011557828.9A Active CN112678806B (en) | 2020-12-25 | 2020-12-25 | Carbon @ SiO x /C @ carbon nanotube composite material and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112678806B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114014328B (en) * | 2021-11-19 | 2023-12-01 | 常州大学 | Preparation method of mesoporous silica microspheres with holes formed by multi-wall carbon nanotubes |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015124049A1 (en) * | 2014-02-18 | 2015-08-27 | 江苏华东锂电技术研究院有限公司 | Preparation method for negative electrode material of lithium ion battery |
| CN107093711A (en) * | 2017-04-01 | 2017-08-25 | 武汉理工大学 | Monodispersed SiOxThe magnanimity preparation method of C complex microspheres |
| CN108493432A (en) * | 2018-05-16 | 2018-09-04 | 杭州电子科技大学 | A kind of preparation method and application of multi-walled carbon nanotube/silicon and silica/carbon composite nano-material |
| CN110931729A (en) * | 2019-10-31 | 2020-03-27 | 合肥国轩高科动力能源有限公司 | Preparation method of multiplying power type lithium ion battery silicon composite oxide material |
-
2020
- 2020-12-25 CN CN202011557828.9A patent/CN112678806B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015124049A1 (en) * | 2014-02-18 | 2015-08-27 | 江苏华东锂电技术研究院有限公司 | Preparation method for negative electrode material of lithium ion battery |
| CN107093711A (en) * | 2017-04-01 | 2017-08-25 | 武汉理工大学 | Monodispersed SiOxThe magnanimity preparation method of C complex microspheres |
| CN108493432A (en) * | 2018-05-16 | 2018-09-04 | 杭州电子科技大学 | A kind of preparation method and application of multi-walled carbon nanotube/silicon and silica/carbon composite nano-material |
| CN110931729A (en) * | 2019-10-31 | 2020-03-27 | 合肥国轩高科动力能源有限公司 | Preparation method of multiplying power type lithium ion battery silicon composite oxide material |
Non-Patent Citations (1)
| Title |
|---|
| Monodisperse and homogeneous SiOx/C microspheres: A promising high-capacity and durable anode material for lithium-ion batteries;Zhenhui Liu等人;《Energy Storage Materials》;20180104;第13卷;摘要，第112页右栏第2段，第113页左栏2.实验部分 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112678806A (en) | 2021-04-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108428876B (en) | High-performance silicon/carbon nano composite negative electrode material and preparation method thereof | |
| CN107611406B (en) | Preparation method of silicon/graphene/carbon composite negative electrode material | |
| CN108172787B (en) | Monodisperse hollow nano silicon/carbon sphere and preparation method and application thereof | |
| CN103311522B (en) | A kind of silicon/carbon composite microsphere negative electrode material and its production and use | |
| CN110556529A (en) | Cathode composite material with multilayer core-shell structure and preparation method and application thereof | |
| CN107579203B (en) | Silicon-doped carbon porous composite film of lithium ion battery and preparation method thereof | |
| CN107946576B (en) | High-rate graphite negative electrode material, preparation method thereof and lithium ion battery | |
| CN110660984B (en) | Nano silicon-carbon composite material and preparation method and application thereof | |
| CN111180714B (en) | Carbon/molybdenum dioxide/silicon/carbon composite material, battery cathode comprising same and lithium ion battery | |
| CN103296261B (en) | The preparation method of lithium ion battery negative material | |
| CN109524643B (en) | Preparation method and application of silicon-based negative electrode material with multilayer carbon shell core-shell structure | |
| CN110620224A (en) | Negative electrode material for lithium battery, preparation method of negative electrode material and lithium battery | |
| CN111082014A (en) | Silicon/carbon nanotube composite material, preparation method thereof, lithium battery cathode and lithium battery | |
| CN104103821B (en) | The preparation method of silicon-carbon cathode material | |
| CN102983317A (en) | Silicon-based composite material and preparation method thereof, silicon-carbon composite material and lithium ion battery | |
| Peng et al. | Insight into the performance of the mesoporous structure SiOx nanoparticles anchored on carbon fibers as anode material of lithium-ion batteries | |
| CN112510185A (en) | Silicon-carbon composite negative electrode material and manufacturing method thereof | |
| CN112768671A (en) | Preparation method of silicon-carbon composite negative electrode material and negative electrode material prepared by preparation method | |
| CN110098402B (en) | Silicon-carbon negative electrode material for lithium ion battery and preparation method thereof | |
| CN109817952B (en) | Lithium ion battery cathode and preparation method thereof | |
| CN110085823B (en) | Nano composite negative electrode material and preparation method and application thereof | |
| CN112678806B (en) | Carbon @ SiO x /C @ carbon nanotube composite material and preparation method thereof | |
| CN113471419A (en) | Silicon-carbon composite material and preparation method and application thereof | |
| CN112421002B (en) | High-capacity silicon-carbon material and preparation method thereof | |
| CN110649237A (en) | Iron oxide @ carbon nanocomposite and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |