CN116779811A - Silicon-containing particle surface elastomer coating layer with organic-inorganic interpenetrating network structure and preparation method thereof - Google Patents
Silicon-containing particle surface elastomer coating layer with organic-inorganic interpenetrating network structure and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a silicon-containing particle surface elastomer coating layer with an organic-inorganic interpenetrating network structure and a preparation method thereof. According to the invention, various macromolecules are adopted to gradually modify the single-wall carbon nano tube, meanwhile, inorganic silicon-containing active particles are added to form an interpenetrating network structure, so that the silicon-containing carbon nano tube has good electronic ion conductivity, excellent viscoelasticity and adhesive force, can be continuously and tightly attached to the surface of the silicon-containing particles in the electrochemical charge-discharge volume expansion and contraction process of the silicon-containing particles, maintains micro and macroscopic stable electrons, ion transmission and the surface smoothness of a negative electrode plate, fully reduces the surface overpotential of the silicon-containing particles, effectively inhibits the overquick growth of SEI films, and realizes high electrochemical charge-discharge stability and extremely high coulomb efficiency.
Description
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a silicon-containing particle surface elastomer coating layer with an organic-inorganic interpenetrating network structure and a preparation method thereof.
Background
The lithium ion battery consists of the following five parts, namely a positive electrode material, a negative electrode material, electrolyte, a diaphragm and a shell, wherein graphite is mainly used as the negative electrode material, the market share is over 90%, but the low gram capacity (372 mAh/g theory) of the lithium ion battery prevents further development. The gram capacity of silicon/silicon oxide exceeds 10 times/5 times of that of graphite, and the silicon/silicon oxide composite material becomes the development direction of lithium ion battery cathode materials with excellent prospects. However, the volume expansion-contraction of silicon >300% and silicon oxide > 200% in charge-discharge cycles seriously affects the stable operation of the lithium ion battery, and at the same time, silicon repeatedly forms an unstable SEI film in the lithium ion battery and accelerates the damage of the electrode sheet.
In order to overcome the problems of low coulombic efficiency and high expansion rate of silicon, there have been many problems at home and abroad, and among many materials, single-walled carbon nanotubes have been confirmed to be effective in improving stability of silicon/silicon oxide during battery cycling, mainly because of the following two aspects: (1) single-walled carbon nanotubes have excellent electrical conductivity. The silicon/silicon oxide is used as a semiconductor and applied to a lithium ion battery, so that the defect of poor conduction exists, and polarization is generated due to extremely uneven lithium intercalation and lithium deintercalation of the silicon/silicon oxide in the battery environment with poor conduction, so that the cycle life of the battery is reduced. The single-wall carbon nano tube has good conductivity, and meanwhile, the nano-scale carbon tube can generate effective electric contact sites with silicon, so that the conductivity of the silicon/silicon oxide anode material is ensured, the electron transmission efficiency is improved, and the comprehensive electrochemical performance is improved. And (2) the single-walled carbon nanotube has the characteristics of hardness and softness. The flexible single-wall carbon nano tube is similar to a chain segment of a polymer molecule, has the characteristic of no displacement caused by local movement and whole body, can effectively relieve the volume expansion of silicon/silicon oxide in the charge and discharge process of a lithium ion battery, and simultaneously has the rebound characteristic, and when the silicon/silicon oxide particles shrink, the single-wall carbon nano tube is well contacted with the silicon/silicon oxide particles, so that the growth of malignant SEI (solid electrolyte interface) is reduced; the rigidity of the single-wall carbon nano tube is high in mechanical strength, so that the surface of the electrode plate is not broken along with the circulation process, and the components are promoted to be tightly combined.
Early research on application of single-walled carbon nanotubes to lithium ion batteries was mainly around the preparation of single-walled carbon nanotubes and silicon composites, such as document 10.1021/jp1063403 (j. Phys. Chem. C2010,114, 15862-15867), which uses Pulsed Laser Deposition (PLD) to deposit silicon onto single-walled carbon nanotube paper to give Si/SWCNT flexible paper. Electrochemical measurement results show that under the charge and discharge condition of 25mA/g, the capacity of the 2.2% Si/SWCNT composite material after 50 cycles is 163mA h g-1, which is improved by more than 60% compared with the original single-walled carbon nanotube. Later, with the development of silicon as a cathode material of a lithium ion battery, a silicon-single-walled carbon nanotube composite system is not only composed of the two materials, but metal, carbon material and other organic/inorganic materials are sequentially introduced into the system, for example, in a document 10.1016/j. Nanoen.2012.09.007, silicon is added into a germanium nanoparticle-single-walled carbon nanotube (Ge-NP: SWCNT) mixed electrode, so that the electrochemical performance of a high-capacity independent anode of the lithium ion battery is improved. Electrochemical tests showed that Si-Ge-NP: the charge capacity of the SWCNT independent anode exceeds 1200mAh/g, and the initial coulombic efficiency is 85%. In addition, the university of Qinghai group Wei Fei is prepared by mixing single-walled carbon nanotubes with SiO with a large aspect ratio X The SiOx@C|SWCNT material is prepared by compounding, the first coulomb efficiency reaches 81.52%, the problem of low first coulomb efficiency of silicon oxide is solved to a certain extent, the capacity of the material is 915.89mAh/g after 200 cycles, and even under the condition that the tensile stress is as high as 6.2GPa, the SWCNTs can be well contacted with SiOx@C, but the problem of large-scale production of single-wall carbon nanotubes with large length-diameter ratio is clear, and the high cost also enables the material to catch the front part in the application of silicon/silicon oxide anode materials. In summary, the high cost of single-walled carbon nanotubes has led to their exposure to the field of composite preparationAnd extremely limited.
In addition to the composite approach described above, another approach of great interest is the incorporation of single-walled carbon nanotubes into binders for application in lithium ion batteries. For example, document 10.1007/s11581-019-03391-w, which improves electrochemical performance by adding small amounts of single-walled carbon nanotubes (SWCNTs) as conductive additives for SiO/C anodes, has a capacity retention of 90.30% after 600 cycles at 1C. The blending system of the single-wall carbon nano tube and the organic binder can greatly buffer the volume expansion of the silicon-based material to a certain extent, and effectively inhibit the structural damage of the electrode. For another example, the university of bloom Wang Jiaping professor task group proposes a "dispersion-anchoring" strategy to improve the uniformity of nano-silicon electrodes to mitigate loss of active species, promoting cycling stability. The initial coulombic efficiency exceeds 89%, and the capacity of 1164.5mAh/g is still provided after 200 cycles, thus the cycle stability is better. For example, chinese patent No. CN112331831B, a specific process is performed by compounding a silicon negative electrode sheet, a porous copper foil, and a single-walled carbon nanotube, so that silicon material particles in a bottom coating of the silicon negative electrode enter into pores of the porous copper foil, and a space for expanding the silicon particles is reserved, and at the same time, the single-walled carbon nanotube can form a conductive network, and its rigidity inhibits expansion and growth of silicon, and its volume energy density exceeds 800Wh/L. For example, in chinese patent No. CN115954458A, the inventor mixes the conventional silicon-based negative electrode binder with the single-walled carbon nanotube by a procedure to obtain a new binder, and the electrochemical test of the silicon-based negative electrode shows that the capacity retention rate is more than 80% after 400 cycles, and the electrode expansion rate is about 60%.
However, most of the above researches are to mechanically mix the single-walled carbon nanotubes with a binder, and the binding additive has poor binding property with silicon-containing particles, and has a great limitation in practical application, such as difficulty in solving the problems of dispersibility of the single-walled carbon nanotubes in an aqueous system, depolymerization of a polymer and the single-walled carbon nanotubes after deep circulation, and influence on the service life of a battery.
Therefore, a silicon-containing particle surface elastomer coating layer with an organic-inorganic interpenetrating network structure and a preparation method thereof are needed to be proposed.
Disclosure of Invention
In order to solve the defects in the prior art, the invention provides a silicon-containing particle surface elastomer coating layer with an organic-inorganic interpenetrating network structure and a preparation method thereof.
In order to solve the technical problems, the invention provides the following technical scheme:
the first object of the invention is to provide a silicon-containing particle surface elastomer coating layer of an organic-inorganic interpenetrating network structure, wherein the elastomer coating layer comprises a grafted 3D network structure and a fabric-like structure, the grafted 3D network structure is formed by inorganic components and organic components, the inorganic components comprise carbon nano tubes and silicon-containing particles, the organic components comprise high polymers A and B, the grafted 3D network structure is used for providing a toughness-rigid framework, and the fabric-like structure is used for increasing the viscoelasticity and the adhesive force of a system.
Preferably, the carbon nanotube is one of a single-walled carbon nanotube and a multi-walled single-walled carbon nanotube; the polymer A and the polymer B are one of polyacrylic acid, sodium carboxymethyl cellulose, chitosan, guar gum, sodium alginate, gellan gum and pectin, and the polymer A and the polymer B adopt different components.
The second object of the invention is to provide a preparation method of a silicon-containing particle surface elastomer coating layer of an organic-inorganic interpenetrating network structure, which comprises the following steps: dispersing carbon nano tube into polymer A solution, adding silicon-containing particles into the solution for further dispersion and compounding, then adding the solution into polymer B solution after spray drying to form flocculating precipitate, collecting the precipitate, and spray drying again to obtain a final product.
Preferably, the method specifically comprises the following steps:
s1, dispersing carbon nano tubes in a polymer A: dissolving the polymer A in water, stirring strongly until a uniform solution is formed, then adding the carbon nano tube, and obtaining a dispersion CNTs/Pol-1@Liq by ultrasonic; wherein, the macromolecule A is represented by Pol-1 when not explicitly indicated;
s2, compounding silicon-containing particles and dispersion CNTs/Pol-1@Liq: adding silicon-containing particles into the dispersion CNTs/Pol-1@Liq prepared in the step S1, performing ultrasonic treatment to obtain uniform dispersion, and performing spray drying to obtain dry powder SiOx/CNTs/Pol-1 (x is more than or equal to 0 and less than or equal to 1);
s3, preparing a final product: uniformly mixing the dry powder SiOx/CNTs/Pol-1 (x is more than or equal to 0 and less than or equal to 1) prepared in the step S2 and the polymer B in water, collecting precipitate, and then spray-drying to obtain dry powder Pol-2/SiOx/CNTs/Pol-1 (x is more than or equal to 0 and less than or equal to 1); wherein the polymer B is not explicitly indicated by Pol-2.
Preferably, the carbon nanotube is one of a single-walled carbon nanotube and a multi-walled single-walled carbon nanotube.
Preferably, the polymer A and the polymer B are one of polyacrylic acid, sodium carboxymethyl cellulose, chitosan, guar gum, sodium alginate, gellan gum and pectin, and the polymer A and the polymer B adopt different components in preparation.
Preferably, the mass ratio of the carbon nano tube to the polymer A is 1 (0.5-2).
Preferably, the mass ratio of the silicon-containing particles to the carbon nanotubes is 8 (0.5-1).
Preferably, the mass ratio of the dry powder SiOx/CNTs/Pol-1 (x is more than or equal to 0 and less than or equal to 1) to the polymer B is (8-10): (0.5-1).
Compared with the prior art, the invention has the following beneficial effects:
the polymer forms a compact wrapping layer on the surface of the silicon-containing particles, and the polymer and a single-wall carbon nanotube skeleton inlaid in the wrapping layer jointly inhibit the overquick growth of the SEI film; the fabric-like structure formed on the surface of the battery pole piece can resist repeated volume expansion and contraction of active silicon-containing particles in the charge and discharge process, and the surface of the electrode is kept in good contact without falling off; the present invention provides excellent viscoelasticity and adhesion to confine the silicon-containing particles and the conductive components in a fixed position so that the silicon/silicon oxide particles do not lose electrical contact during charge-discharge expansion, resulting in high first coulombic efficiency of the nano-silicon/silicon oxide anode through synergy between the components.
According to the invention, various macromolecules are adopted to gradually modify the single-wall carbon nano tube, meanwhile, inorganic silicon-containing active particles are added to form an interpenetrating network structure, so that the silicon-containing carbon nano tube has good electronic ion conductivity, excellent viscoelasticity and adhesive force, can be continuously and tightly attached to the surface of the silicon-containing particles in the electrochemical charge-discharge volume expansion and contraction process of the silicon-containing particles, maintains micro and macroscopic stable electrons, ion transmission and the surface smoothness of a negative electrode plate, fully reduces the surface overpotential of the silicon-containing particles, effectively inhibits the overquick growth of SEI films, and realizes high electrochemical charge-discharge stability and extremely high coulomb efficiency.
Drawings
FIG. 1 is a reference graph of the relative motion mechanism of additives and silicon-based particles during charge and discharge according to the present invention;
FIG. 2 is a schematic diagram of the fragmentation of silicon particles before and after charging and discharging in accordance with the present invention;
FIG. 3 is an SEM image of the surface of a negative electrode sheet prepared in example 1 of the present invention;
FIG. 4 is an SEM image (another area) of the surface of a negative electrode sheet prepared according to example 1 of the present invention;
FIG. 5 is a charge-discharge curve of the negative electrode sheet prepared in example 1 of the present invention;
FIG. 6 is an electrochemical impedance spectrum of the negative electrode tab prepared in example 1 and comparative example 3 of the present invention after 50 cycles.
Detailed Description
The preferred embodiments of the present invention will be described below with reference to the accompanying drawings, it being understood that the preferred embodiments described herein are for illustration and explanation of the present invention only, and are not intended to limit the present invention.
Example 1
The embodiment provides a silicon-containing particle surface elastomer coating layer of an organic-inorganic interpenetrating network structure, wherein the elastomer coating layer comprises a grafted 3D network structure and a fabric-like structure, the grafted 3D network structure is formed by inorganic components and organic components, the inorganic components comprise carbon nanotubes and silicon-containing particles, the organic components comprise a polymer A and a polymer B, the grafted 3D network structure is used for providing a toughness-rigid framework, and the fabric-like structure is used for increasing the viscoelasticity and the adhesive force of a system.
The embodiment also provides a preparation method of the elastomer coating layer on the surface of the silicon-containing particles with the organic-inorganic interpenetrating network structure, which comprises the steps of dispersing the carbon nano tubes into the polymer A solution, adding the silicon-containing particles into the polymer A solution for further dispersion and compounding, adding the silicon-containing particles into the polymer B solution after spray drying to form flocculating precipitates, collecting the precipitates, and spray drying again to obtain a final product. Specifically, the preparation method comprises the following steps:
(1) Dispersion of single-walled carbon nanotubes in polymer a: 2g of sodium carboxymethylcellulose is weighed and dissolved in 198g of water, and is stirred strongly until a uniform and transparent solution is formed, and 1g of single-wall carbon nano tube is weighed and added into the solution, and is dispersed uniformly by ultrasonic gun to obtain dispersion CNTs/CMC@Liq, wherein the ultrasonic conditions are as follows: 40-50W, and the duration is 1h.
(2) Silicon-containing particles and CNTs/Pol-1@Liq are compounded: weighing 8gSi particles, adding the particles into 100ml of CNTs/CMC@Liq, performing ultrasonic treatment to obtain uniform dispersion liquid, and performing spray drying to obtain dry powder Si/CNTs/CMC. The ultrasonic conditions are as follows: 40-50W, and the duration is 1h. The spray drying conditions were: air inlet temperature: 220 ℃, outlet temperature: 100 ℃, feed rate: 5ml/min.
(3) Preparation of the final product: uniformly mixing the dry powder Si/CNTs/CMC in the step (2) with polyacrylic acid with the mass of 0.5g in 200ml of water, and spray-drying to obtain the dry powder PAA/Si/CNTs/CMC (0.5:8:0.5:1).
Example 2
The preparation process according to example 1 differs from example 1 in that: and the polymer B is chitosan, and finally, dry powder CTS/Si/CNTs/CMC (0.5:8:0.5:1) is obtained.
Example 3
The preparation process according to example 1 differs from example 1 in that: and selecting sodium alginate from the polymer B to finally obtain dry powder SA/Si/CNTs/CMC (0.5:8:0.5:1).
Example 4
The preparation process according to example 1 differs from example 1 in that: polymer A was selected as gellan gum and the resulting powder was designated CTS/Si/CNTs/GG (0.5:8:0.5:1).
Example 5
The preparation process according to example 1 differs from example 1 in that: the polymer A is selected as pectin, and finally the dry powder CTS/Si/CNTs/PT (0.5:8:0.5:1) is obtained.
Example 6
The preparation process according to example 1 differs from example 1 in that: in the step (1), the mass ratio of the single-walled carbon nanotube to the sodium carboxymethylcellulose is 1:1, and finally, dry powder PAA/Si/CNTs/CMC (0.5:8:0.5:0.5) is obtained.
Example 7
The preparation process according to example 1 differs from example 1 in that: in the step (1), the mass ratio of the single-walled carbon nanotube to the sodium carboxymethylcellulose is 1:0.5, and finally, dry powder PAA/Si/CNTs/CMC (0.5:8:0.5:0.25) is obtained.
Example 8
The preparation process according to example 1 differs from example 1 in that: in the step (2), the mass ratio of the silicon particles to the single-walled carbon nanotubes is 8:1, and finally, dry powder PAA/Si/CNTs/CMC (0.5:8:1:2) is obtained.
Example 9
The preparation process according to example 1 differs from example 1 in that: in the step (2), the mass ratio of the silicon particles to the single-walled carbon nanotubes is 9:1, and finally, dry powder PAA/Si/CNTs/CMC (1:8:0.33:0.67) is obtained.
Example 10
The preparation process according to example 1 differs from example 1 in that: and (3) selecting silicon-containing particles as SiO in the step (2), and finally obtaining dry powder PAA/SiO/CNTs/CMC (0.5:8:0.5:1).
Example 11
The preparation process according to example 1 differs from example 1 in that: in the step (2), the silicon-containing particles are selected as a mixture with the mass ratio of SiO to Si being 1:1, and finally, dry powder PAA/SiO@Si/CNTs/CMC (0.5:8:0.5:1) is obtained.
Comparative example 1
The preparation process according to example 1 differs from example 1 in that: 0.1g of single-walled carbon nanotubes were used in step (1).
Comparative example 2
The preparation process according to example 1 differs from example 1 in that: there is no step (3).
Comparative example 3
The preparation process according to example 1 differs from example 1 in that: step (1) does not add single-walled carbon nanotubes.
Performance detection
Figures 1 and 2 demonstrate the relative movement change of each component of the system and the working principle of the elastic coating layer on the surface of the silicon-containing particles during the lithium intercalation-deintercalation process, respectively.
(1) The structure and morphology of the negative electrode sheet are characterized as follows:
the negative electrode piece prepared in example 1 was subjected to Scanning Electron Microscope (SEM) characterization, and as shown in fig. 2 and 3, a braid-like structure using single-walled carbon nanotubes as a skeleton was observed on the surface of the negative electrode material, and particularly "well" and "o" shaped surfaces were observed in fig. 3.
Characterization is carried out on the charge and discharge performance of the first ring of the cathode electrode plate prepared in the embodiment 1, and the detection method is as follows: after standing for 12 hours, under the condition of a charge-discharge multiplying power of 0.1C, firstly discharging to 0.001V to obtain a discharge curve, and then recharging to 2V to obtain a charge curve, wherein as shown in figure 4, the first-circle charge-discharge capacity of the composite material is 3295.0mAh/g and 3631.8mAh/g respectively, and the first-circle coulomb efficiency is 87.2%.
The elastic coating layer/silicon-containing particle composite material prepared in example 1 was subjected to cycle performance characterization, and the detection method was as follows: under the condition of a charge-discharge multiplying power of 0.2C, discharging to 0.001V to obtain discharge capacity, recharging to 2V to obtain charge capacity, and obtaining discharge-charge specific capacities respectively through mass normalization.
(2) Mass fraction and lithium storage properties of silicon/silicon oxide based materials:
the silicon/silicon oxide-based composite material prepared in the embodiment is subjected to electrochemical performance test, wherein the electrochemical performance test is carried out by assembling CR2032 button half cells, and the specific assembling method comprises the following steps:
a metal lithium sheet with the thickness of 1mm and the diameter of 16mm is used as a counter electrode; at 1mol/L LiPF 6 EC: DEC: DMC (1:1:1) is electrolyte; taking a polypropylene microporous membrane as a diaphragm; the battery was assembled in a glove box filled with Ar gas.
The model of the battery test system is LAND CT3002A, and the voltage range is 0.001-2V.
The lithium storage performance of the prepared electrode sheet is detected as follows (table 1):
as can be seen from the data in table 1, the prepared surface elastomer coating layer of the silicon-containing particles with the organic-inorganic interpenetrating network structure improves the first coulombic efficiency and the cyclic stability of the negative electrode plate of the silicon-containing particles.
Comparison of the test results according to examples 1-5 shows that sodium carboxymethylcellulose and polyacrylic acid are more suitable as polymer A, B. For the polymer A, gellan gum and pectin are difficult to play the role of dispersing the single-walled carbon nanotubes, so that the single-walled carbon nanotubes are difficult to disperse uniformly in a system, and when the single-walled carbon nanotubes are dispersed in carboxymethyl cellulose by ultrasonic, the polymer A can be attached to the single-walled carbon nanotubes, so that a good dispersing effect is achieved; for the polymer B, polyacrylic acid brings stronger adhesiveness and cohesive force, and although the mechanical strength of sodium alginate and chitosan is higher to inhibit the expansion of silicon-containing particles, the brittleness of the polyacrylic acid is higher than that of the polyacrylic acid, so that the silicon-containing particles are difficult to continue to bear the cohesive effect after being disintegrated and pulverized.
The effect of the content of the components on the electrochemical performance of the half-cell is demonstrated according to examples 1, 6 to 9. The proper use of the single-walled carbon nanotubes plays a better role in protecting the surface of the polar plate, an organic-inorganic interpenetrating network formed by taking the single-walled carbon nanotubes as a 3D framework forms a compact wrapping layer on the surface of the silicon-containing particles, and the best electrochemical performance is obtained in the embodiment 1 with reference to the electron microscope figures 3 and 4, wherein the overall content of the single-walled carbon nanotubes is 5 weight percent. In addition, the ratio of the polymer A, B also directly affects the electrochemical lithium storage performance of the silicon-containing particles, and the optimal ratio of the polymer A, B is 1:1. the additive amount of the single-wall carbon nano tube in the comparative example 1 is extremely low, and the requirement of preparing the organic-inorganic interpenetrating network elastomer coating layer is hardly met, so that the obtained negative electrode plate has poor cycle performance, and good electrochemical performance is hardly obtained by only using one polymer in the comparative example 2, because the adhesive performance is concentrated on one polymer, and no additional performance supplement exists.
While examples 1, 10 and 11 demonstrate that the surface elastomer coating layer of the silicon-containing particles with the organic-inorganic interpenetrating network structure prepared by the invention is favorable for improving the first coulombic efficiency of the silicon-containing particles (SiOx, 0.ltoreq.X.ltoreq.1) and has more stable cycle performance, particularly the first coulombic efficiency of SiO is difficult to break through to 60 percent, but can reach 78.8 percent in the example due to the modification of the SiO particles by the organic-inorganic interpenetrating network elastomer coating layer. The comparison between example 1 and comparative example 3 shows that the single-walled carbon nanotubes have a critical role in the organic-inorganic interpenetrating network, and the electrochemical properties show that the single-walled carbon nanotubes not only improve the first coulombic efficiency of pure silicon particles, but also greatly improve the cycle performance. In addition, fig. 6 shows electrochemical impedance spectra after 50 cycles of the samples of example 1 and comparative example 3, the samples of example 1 show lower electron transfer resistance (47 Ω) and greater Warburg slope, and the sample of comparative example 3 has electron transfer resistance much greater than 47 Ω, so fig. 6 demonstrates the necessity of single-walled carbon nanotubes, while enhancing electron and ion transport efficiency in the cell, and still function properly after swelling and fragmentation of the silicon-containing particles.
In conclusion, the interpenetrating network structure has good electronic ion conductivity, excellent viscoelasticity and adhesive force, can be continuously and tightly attached to the surface of the silicon-containing particles in the electrochemical charge-discharge volume expansion and contraction process of the silicon-containing particles, maintains micro and macroscopic stable electrons, ion transmission and flat surface of the negative electrode plate, fully reduces the surface overpotential of the silicon-containing particles, effectively inhibits the overfast growth of SEI films, and realizes high electrochemical charge-discharge stability and extremely high coulomb efficiency.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present invention, and the present invention is not limited thereto, but it is to be understood that modifications and equivalents of some of the technical features described in the foregoing embodiments may be made by those skilled in the art, although the present invention has been described in detail with reference to the foregoing embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. The elastic coating layer on the surface of the silicon-containing particles of the organic-inorganic interpenetrating network structure is characterized by comprising a grafted 3D network structure and a fabric-like structure, wherein the grafted 3D network structure is formed by inorganic components and organic components, the inorganic components comprise carbon nanotubes and silicon-containing particles, the organic components comprise a polymer A and a polymer B, the grafted 3D network structure is used for providing a toughness-rigid framework, and the fabric-like structure is used for increasing the viscoelasticity and the adhesive force of a system.
2. The silicon-containing particle surface elastomer coating of an organic-inorganic interpenetrating network structure according to claim 1, wherein the carbon nanotube is one of a single-walled carbon nanotube and a multi-walled single-walled carbon nanotube; the polymer A and the polymer B are one of polyacrylic acid, sodium carboxymethyl cellulose, chitosan, guar gum, sodium alginate, gellan gum and pectin, and the polymer A and the polymer B adopt different components.
3. A method for preparing the elastomer coating layer on the surface of the silicon-containing particles of the organic-inorganic interpenetrating network structure according to claim 1, which comprises the following steps: dispersing carbon nano tube into polymer A solution, adding silicon-containing particles into the solution for further dispersion and compounding, then adding the solution into polymer B solution after spray drying to form flocculating precipitate, collecting the precipitate, and spray drying again to obtain a final product.
4. The method for preparing the elastomer coating layer on the surface of the silicon-containing particles of the organic-inorganic interpenetrating network structure according to claim 3, which is characterized by comprising the following steps:
s1, dispersing carbon nano tubes in a polymer A: dissolving the polymer A in water, stirring strongly until a uniform solution is formed, then adding the carbon nano tube, and obtaining a dispersion CNTs/Pol-1@Liq by ultrasonic;
s2, compounding silicon-containing particles and dispersion CNTs/Pol-1@Liq: adding silicon-containing particles into the dispersion CNTs/Pol-1@Liq prepared in the step S1, performing ultrasonic treatment to obtain uniform dispersion, and performing spray drying to obtain dry powder SiOx/CNTs/Pol-1 (x is more than or equal to 0 and less than or equal to 1);
s3, preparing a final product: uniformly mixing the dry powder SiOx/CNTs/Pol-1 (x is more than or equal to 0 and less than or equal to 1) prepared in the step S2 and the polymer B in water, collecting precipitate, and then spray-drying to obtain the dry powder Pol-2/SiOx/CNTs/Pol-1 (x is more than or equal to 0 and less than or equal to 1).
5. The method for preparing the elastomer coating layer on the surface of the silicon-containing particles with the organic-inorganic interpenetrating network structure according to claim 1, wherein the carbon nanotube is one of a single-walled carbon nanotube and a multi-walled single-walled carbon nanotube.
6. The method for preparing the silicon-containing particle surface elastomer coating layer with the organic-inorganic interpenetrating network structure according to claim 1, wherein the polymer A and the polymer B are one of polyacrylic acid, sodium carboxymethyl cellulose, chitosan, guar gum, sodium alginate, gellan gum and pectin, and different components are adopted in the preparation of the polymer A and the polymer B.
7. The method for preparing the elastomer coating layer on the surface of the silicon-containing particles with the organic-inorganic interpenetrating network structure according to claim 1, wherein the mass ratio of the carbon nano tube to the polymer A is 1 (0.5-2).
8. The method for preparing the elastomer coating layer on the surface of the silicon-containing particles with the organic-inorganic interpenetrating network structure according to claim 1, wherein the mass ratio of the silicon-containing particles to the carbon nano tubes is 8 (0.5-1).
9. The method for preparing the elastomer coating layer on the surface of the silicon-containing particles with the organic-inorganic interpenetrating network structure according to claim 1, wherein the mass ratio of dry powder SiOx/CNTs/Pol-1 (x is more than or equal to 0 and less than or equal to 1) to polymer B is (8-10): (0.5-1).
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