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CN-116995204-B - Preparation method and application of silica-carbon composite material with three-dimensional ordered macroporous structure

CN116995204BCN 116995204 BCN116995204 BCN 116995204BCN-116995204-B

Abstract

The invention relates to a preparation method and application of a silica-carbon composite material with a three-dimensional ordered macroporous structure. The method uses organosilane as a silicon source, wherein the organosilane is provided with organic units, uniform carbon doping can be realized in the final product 3DOM SiO x after sol-gel and heat treatment, the structure is combined with chemical vapor deposition to perform uniform carbon coating, and the obtained product has a honeycomb-like structure and regular and ordered macropores. The preparation method has the advantages of simple preparation process, high repeatability, high capacity, coulomb efficiency, stability and the like, and the preparation method is used as an electrode material of a lithium ion battery, and has excellent electrochemical performance due to the synergistic effect of the honeycomb 3DOM structure and carbon combination, so that the preparation method has great potential and application value in the aspect of pushing three-dimensional nanostructure engineering.

Inventors

  • ZHANG XU
  • WANG ZHIYUAN
  • SUN XINXIN
  • Si Kaize
  • WANG XIAOMEI

Assignees

  • 河北工业大学

Dates

Publication Date
20260512
Application Date
20230717

Claims (6)

  1. 1. The preparation method of the silica-carbon composite material with the three-dimensional ordered macroporous structure is characterized by comprising the following steps of: (1) Vacuum processing is carried out on a colloidal crystal template (CLPS CCTS) formed by crosslinked polystyrene microspheres, a catalyst and organosilane are dissolved in ethanol, then the catalyst and organosilane are injected into the processed template, after soaking for 0.1-4 hours, redundant liquid is removed, and the solution is kept stand for 0.1-30 hours at 10-70 ℃, and the composite material of the CLPS CCTS filled with polysilsesquioxane is obtained after drying, namely polysilsesquioxane/CLPS; Wherein the volume ratio of the ethanol to the catalyst to the organosilane is 0.1-8:0.1-8:1; The organosilane is one or more of siloxane or chlorosilane; The catalyst is ammonia water, nitric acid, sulfuric acid, hydrochloric acid, acetic acid or sodium hydroxide solution; (2) Pyrolyzing polysilsesquioxane/CLPS for 0.1-20 hours in an inert atmosphere at 350-1200 ℃ to obtain 3DOM-SC powder; (3) Carrying out chemical vapor deposition on 3DOM-SC powder at 350-1200 ℃ for 0.1-48 hours, wherein the gas atmosphere is a mixed atmosphere, and finally obtaining the silicon oxide-carbon composite material with a three-dimensional ordered macroporous structure, namely 3DOM-SC@C; The mixed atmosphere is a mixture of A gas and B gas, wherein the A gas is one or two of nitrogen and argon, the B gas is one or more of methane, ethylene and acetylene, and the volume fraction of the B gas is 1-72%.
  2. 2. The method for preparing the silica-carbon composite material with the three-dimensional ordered macroporous structure as claimed in claim 1, wherein the organosilane is one or more of vinyl triethoxysilane, 3-aminopropyl triethoxysilane, 3-mercaptopropyl triethoxysilane, methyltrichlorosilane, 3-mercaptopropyl trimethoxysilane, vinyl trimethoxysilane and trimethylchlorosilane.
  3. 3. The method for preparing a silica-carbon composite material having a three-dimensional ordered macroporous structure as claimed in claim 1, wherein the inert gas is one or both of nitrogen and argon.
  4. 4. The method for preparing the silica-carbon composite material with the three-dimensional ordered macroporous structure as claimed in claim 1, wherein the composite material is of the three-dimensional ordered macroporous structure, the pore diameter of macropores is 200-500 nm, the macropores are regularly 'pore windows', a framework is composed of a composite of nano SiO x /C, and the surface of the composite material is coated with a carbon coating.
  5. 5. The use of the silica-carbon composite material with a three-dimensional ordered macroporous structure prepared by the method of claim 1, as a negative electrode material for lithium ion batteries.
  6. 6. The application of claim 5, wherein the lithium ion battery is constructed by adopting a button cell, assembling a negative electrode shell, a spring piece, a gasket, a negative electrode piece, a diaphragm, a positive electrode piece and a positive electrode shell in sequence, and filling electrolyte; The electrode plate comprises a cathode plate, an anode plate and an anode plate, wherein the loading capacity of the unit area of the electrode plate is 1.0-2.0 mg cm -2 , the anode plate is a working electrode, the anode plate is a lithium plate, the working electrode is prepared by mixing obtained nano particles, acetylene black or Surper P, sodium alginate or carboxymethyl cellulose into slurry at a mass ratio of 75:10:15, coating the slurry on a copper foil, drying and cutting the slurry; the diaphragm model is Celgard 2400; the electrolyte is prepared by dissolving lithium hexafluorophosphate in ethylene carbonate, dimethyl carbonate and ethylmethyl carbonate with equal volume ratio, and the concentration is 0.5-2.5 mol/L.

Description

Preparation method and application of silica-carbon composite material with three-dimensional ordered macroporous structure Technical Field The invention belongs to the field of nano materials and the field of electrochemical energy storage, and particularly relates to a preparation method of a silicon oxide-carbon composite material (hereinafter referred to as 3 DOM-SC@C) with a three-dimensional ordered macroporous structure, which is used as a negative electrode material of a lithium ion battery. Background Lithium Ion Batteries (LIBs) are the most potential energy storage systems in many secondary batteries due to their high energy density and high operating voltage. However, the limited capacity (372 mAh/g) of commercial graphite cathodes in LIBs is not satisfactory for the increasing demand of energy storage devices for high energy density, and therefore there is a need to develop new LIBs cathode materials with high performance (Lee S M,Kim J,Moon J,et al.A cooperative biphasic MoOx–MoPx promoter enables a fast-charging lithium-ion battery[J].Nature Communications,2021,12(1):39.). Silicon oxide (SiO x, 0< x≤2) becomes a candidate anode material of the next generation of high energy density LIBs due to the high capacity (2000 mAh/g). However, siO x still expands (200%) and contracts in the charge-discharge cycle process, which leads to pulverization and collapse of electrode materials, and in addition, the low electron conductivity and the low coulombic efficiency caused by more irreversible reactions occurring in the lithiation/delithiation process limit the practical application of SiO x in lithium storage (Ouyang Q,Li G,Zhang X,et al.Towards high-capacity lithium ion batteries:constructing hollow-structured SiOx-based nanocube anode via a sequential coating strategy[J].Chemical Engineering Journal,2023,460,141762.). In recent years, numerous studies have shown that the construction of nanostructures and the incorporation of carbon is one of the effective methods for solving the above-mentioned problems. In other words, the nanostructure reduces the ion and electron transport paths to the nanoscale, its large specific surface area promotes full electrode/electrolyte contact, promotes the complete lithiation process, carbon coating and carbon doping can significantly enhance conductivity, provide a fast path for electron and ion transport, and simultaneously reduce the volume change of SiO x. The method is expected to improve the electrochemical reaction kinetics of SiO x and Li, and the anode material with excellent performance is obtained (Lui G,Li G,Wang X,et al.Flexible,three-dimensional ordered macroporous TiO2 electrode with enhanced electrode-electrolyte interaction in high-power Li-ion batteries[J].Nano Energy,2016,24,72-77;Li Z,Zhao H,Lv P,et al.Watermelon-like structured SiOx-TiO2@C nanocomposite as a high-performance lithium-ion battery anode[J].Advanced Functional Materials,2018,28,1605711.). However, carbon coating and carbon doping have limited efforts in improving electrochemical performance, and may require the incorporation of nanostructures. Currently, 0D, 1D and 2D nanostructures have been successfully prepared, which can effectively increase the electrochemical reaction rate of materials, a large specific surface area provides a large number of active sites, good ion/electron transport kinetics, enhanced lithium storage capacity, and more significant increases in electrochemical activity with further reductions in particle size. However, overdriving the particle size to smaller sizes tends to result in a multiple increase in energy consumption. In addition, 0D, 1D and 2D materials are easily stacked in a long-term cycle, so that there are problems in that (1) mass transfer process in the electrode is hindered, (2) contact area between the electrolyte and the electrode is reduced, which is unfavorable for complete lithiation of the active material, and (3) the large specific surface area thereof causes more irreversible reactions to occur in the cycle process, resulting in a decrease in coulombic efficiency. The above-described methods and material systems have difficulty achieving satisfactory kinetics of the electrochemical reaction of SiO x with Li. Thus, combining higher dimensional nanostructures with carbon may be an effective way to break the bottleneck. In short, there is an urgent need to develop an effective strategy for synthesizing carbon-coated 3D nanostructure materials for electrochemical performance research of LIBs negative electrodes to solve the problems of high expansion and low conductivity, thereby developing lithium ion batteries with high energy density and high cycling stability (Wang R,Wang J,Chen S,et al.Toward mechanically stable silicon-based anodes using Si/SiOx@C hierarchical structures with well-controlled internal buffer voids[J].ACS Applied Materials&Interfaces,2018,10,41422-41430;Ding Y,Wang C,Zheng R,et al.Three-dimensionally ordered macroporous