CN112479188B - Silicon-doped graphene aerogel and preparation method and application thereof - Google Patents

Silicon-doped graphene aerogel and preparation method and application thereof Download PDF

Info

Publication number
CN112479188B
CN112479188B CN202011325444.4A CN202011325444A CN112479188B CN 112479188 B CN112479188 B CN 112479188B CN 202011325444 A CN202011325444 A CN 202011325444A CN 112479188 B CN112479188 B CN 112479188B
Authority
CN
China
Prior art keywords
silicon
graphene aerogel
doped graphene
graphene
application
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
Application number
CN202011325444.4A
Other languages
Chinese (zh)
Other versions
CN112479188A (en
Inventor
姜立运
于琦
蒋剑超
任帅
张永宏
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shaanxi University of Technology
Original Assignee
Shaanxi University of Technology
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shaanxi University of Technology filed Critical Shaanxi University of Technology
Priority to CN202011325444.4A priority Critical patent/CN112479188B/en
Publication of CN112479188A publication Critical patent/CN112479188A/en
Application granted granted Critical
Publication of CN112479188B publication Critical patent/CN112479188B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/15—Nano-sized carbon materials
    • C01B32/182—Graphene
    • C01B32/184—Preparation
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/15—Nano-sized carbon materials
    • C01B32/182—Graphene
    • C01B32/198—Graphene oxide
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22—Electrodes
    • H01G11/24—Electrodes characterised by structural features of the materials making up or comprised in the electrodes, e.g. form, surface area or porosity; characterised by the structural features of powders or particles used therefor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22—Electrodes
    • H01G11/30—Electrodes characterised by their material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22—Electrodes
    • H01G11/30—Electrodes characterised by their material
    • H01G11/32—Carbon-based
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/84—Processes for the manufacture of hybrid or EDL capacitors, or components thereof
    • H01G11/86—Processes for the manufacture of hybrid or EDL capacitors, or components thereof specially adapted for electrodes
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2204/00—Structure or properties of graphene
    • C01B2204/20—Graphene characterized by its properties
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2204/00—Structure or properties of graphene
    • C01B2204/20—Graphene characterized by its properties
    • C01B2204/22—Electronic properties
    • 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
    • Y02E60/13—Energy storage using capacitors

Abstract

The invention provides a silicon-doped graphene aerogel and a preparation method and application thereof, which are used for preparing the silicon-doped graphene aerogel and researching the electrochemical performance of the silicon-doped graphene aerogel, wherein graphene oxide is used as a carbon source, silicon dioxide is used as a silicon source, and graphene dispersion liquids with different concentrations are prepared; the silicon-doped graphene aerogel with stable and high performance is prepared by a one-step hydrothermal synthesis method. According to the invention, the product obtained through the hydrothermal reaction has a special three-dimensional porous structure, and the interconnected mesopores on the surface of the silicon-doped graphene aerogel inhibit the agglomeration phenomenon of graphene sheets, so that the specific surface area of the macroscopic graphene material is greatly increased. Meanwhile, the three-dimensional porous structure with distinct layers can improve the ion transmission efficiency, so that the electrochemical performance of the silicon-doped graphene aerogel as the electrode of the supercapacitor is improved.

Description

Silicon-doped graphene aerogel and preparation method and application thereof
[ technical field ] A method for producing a semiconductor device
The invention belongs to the technical field of high-performance super capacitors, and particularly relates to a silicon-doped graphene aerogel and a preparation method and application thereof.
[ background ] A method for producing a semiconductor device
Graphene is a two-dimensional carbon material (0.334 nm) with a single atomic layer thickness, the stable and special crystal structure determines that graphene has excellent thermal conductivity, electrical conductivity, large surface area, good mechanical properties and easily-modified surface chemistry, and compared with the traditional porous carbon material, graphene has high electrical conductivity (10 mm) 4 ～10 6 S/m), large specific surface area (-2675 m) 2 A/g), a high Young's modulus (1 TPa) and a high breaking strength (130 GPa),the intrinsic graphene has fewer functional groups and poorer compatibility with an organic solvent, and can generate low on-off ratio and large leakage current when applied to an electronic device, so that the functional development of the intrinsic graphene is severely restricted, therefore, the doping of the non-metal heteroatom can adjust the energy band structure of the graphene, further improve the performance of the graphene aerogel, and the intrinsic graphene is considered to be a super capacitor with great application prospect.
Aerogel materials generally refer to three-dimensional porous ultra-light solid materials in which nanoparticles are aggregated to form a nanopore structure, and gas-state dispersion media are filled in the nanopores. The carbon aerogel as a novel amorphous nano material has the advantages of large specific surface area, high porosity, stable physical and chemical properties and the like, is particularly suitable for serving as a catalyst and a carrier thereof, and has excellent thermal conductivity and electrical conductivity. Graphene aerogel is a macroscopic three-dimensional porous structure constructed from two-dimensional graphene sheets. The graphene aerogel composite material has the excellent characteristics of graphene and aerogel, and has more excellent electrical conductivity, thermal conductivity and mechanical strength. The main preparation method of the graphene aerogel comprises the following steps: in-situ assembly, templating, chemical cross-linking, and 3D printing techniques. How to promote the electrochemical performance of graphene aerogel, expand the application field of graphene aerogel for the problem that needs to be solved is that this material can obtain abundant application.
[ summary of the invention ]
The invention aims to overcome the defects of the prior art, and provides a silicon-doped graphene aerogel and a preparation method and application thereof, so as to solve the technical problems that the electrochemical performance of the graphene aerogel is not improved and the application field of the graphene aerogel is expanded in the prior art.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:
a preparation method of silicon-doped graphene aerogel comprises the following steps:
step 1, mixing natural graphite powder and concentrated sulfuric acid, adding sodium nitrate after stirring to form a mixture A, cooling the mixture A to 0 ℃, adding potassium permanganate, and heating in a water bath to form a slurry B;
step 2, adding deionized water and H into the slurry B 2 O 2 After the mixture is changed from brown to light yellow, washing the mixed solution C by dilute hydrochloric acid, centrifuging the washed mixed solution C, and ultrasonically dispersing the centrifuged solution in water to obtain a GO dispersion liquid;
and 3, mixing the GO dispersion liquid with silicon dioxide, carrying out hydrothermal reaction, airing a product, and carrying out vacuum drying to obtain the silicon-doped graphene aerogel.
The invention is further improved in that:
preferably, in the step 1, the mixing ratio of the natural graphite powder to the concentrated sulfuric acid is 1g:23mL, 0.5g of sodium nitrate was added.
Preferably, in step 1, 3g of potassium permanganate is correspondingly added to 1g of natural graphene powder.
Preferably, in the step 1, the water bath heating temperature is 35-40 ℃, and the water bath heating time is 30min.
Preferably, in step 2, the ultrasonic dispersion time is 3h, and the concentration of the GO dispersion liquid is 1-8 mg/mL.
Preferably, in step 3, the mass of silica added is 15% of the mass of the GO dispersion.
Preferably, in the step 3, the hydrothermal reaction temperature is 180 ℃ and the hydrothermal reaction time is 12h.
Preferably, in step 3, the vacuum drying time is 72h.
The silicon-doped graphene aerogel prepared by the preparation method is formed by winding lamellar graphene sheets, three-dimensional holes are formed among the wound graphene sheets, silicon atoms are doped in the holes, and the size of the holes is 1-100 nm.
An application of the silicon-doped graphene aerogel in the field of capacitors.
Compared with the prior art, the invention has the following beneficial effects:
the invention discloses a preparation method of silicon-doped graphene aerogel, which is simple, adopts a hydrothermal method with a simple synthesis principle and easy control of sample morphology, synthesizes Si-GA with high porosity by taking graphene oxide as a carbon source and silicon dioxide as a silicon source, firstly prepares GO dispersion liquid by an improved Hummers method, increases oxygen-containing functional groups on the GO dispersion liquid after oxidation to make the GO dispersion liquid more active than graphene, and can improve the property of the GO dispersion liquid through various reactions with the oxygen-containing functional groups, and the introduction of the oxygen-containing groups not only enables the graphene oxide to have chemical stability, but also provides surface modification active sites and larger specific surface area for synthesizing graphene base/graphene oxide base materials. And because the basal plane and the edge of the graphene lamellar skeleton are provided with structures with various oxygen-containing functional groups, the conductivity and the band gap of the graphene oxide can be adjusted by regulating the types and the number of the oxygen-containing functional groups, the intrinsic graphene functional groups are fewer and the compatibility with an organic solvent is poor, so that the energy band structure of the graphene can be adjusted by doping non-metal silicon atoms, the performance of the graphene aerogel is further improved, and then the silicon-doped graphene aerogel with high performance is stabilized by utilizing a hydrothermal synthesis method. The synthesis method is simple, expensive experimental equipment is not needed, the cost is greatly reduced, large-area preparation can be carried out, and the hydrothermal method is widely applied due to the simplicity, commercial feasibility and good potential of large-scale production, so that the method has wide application prospect in the aspect of industrial production. The Si-GA with high porosity is synthesized by a one-step hydrothermal method, and the Si-GA shows ultrahigh specific capacitance, good rate performance and long cycle life.
The invention also discloses a silicon-doped graphene aerogel, which is a macroscopic three-dimensional porous structure constructed by two-dimensional graphene sheets. The graphene aerogel composite material has the excellent characteristics of graphene and aerogel, and has more excellent electrical conductivity, thermal conductivity and mechanical strength; the aerogel has a macroscopic three-dimensional porous structure constructed by two-dimensional graphene sheets. The Si-GA is communicated with each other and has a three-dimensional porous structure with clear layers. The Si-GA lamella is completely and effectively stacked to form a boundary with clear layers, the holes of the Si-GA are between several microns and dozens of nanometers, the three-dimensional structure of the interconnected mesopores on the surface of the silicon-doped graphene aerogel prevents the graphene lamella from agglomerating in a large range, and the specific surface area of a macroscopic graphene material is increased, so that the ion transmission efficiency and specific capacitance of the Si-GA are greatly improved, and all the effects are attributed to the restoration of graphene conjugated pi bonds (the aperture ratio can influence the capacitance, and the Si can improve the capacitance performance). Meanwhile, due to the fact that the hydrothermal reaction is carried out, the gauze-shaped graphene is mutually wound due to the chemical crosslinking effect, which is an important reason for forming the three-dimensional porous Si-GA, and the capacitance performance of the graphene aerogel can be improved by the graphene with Si atoms doped in the holes. TGA tests show that a great amount of oxygen-containing functional groups in Si-GA are removed in the hydrothermal reduction process, so that Si-GA has better thermal stability than GO. The prepared Si-GA has high specific capacitance (348.5F/g at 1A/g), excellent rate performance and long cycle life.
The invention also discloses application of the silicon-doped graphene aerogel in the field of capacitors, and the Si-GA obtained through hydrothermal reaction has a three-dimensional porous structure, and shows ultrahigh specific capacitance, good rate performance and long cycle life. The three-dimensional porous structure with distinct layers can improve the ion transmission efficiency, so that the electrochemical performance of the silicon-doped graphene aerogel as a supercapacitor electrode is improved.
[ description of the drawings ]
FIG. 1 is an XRD pattern of the undoped and Si-GA nanoporous structures after 12 hours of hydrothermal growth at 180 ℃.
FIG. 2 is an SEM photograph of Si-GA after hydrothermal growth at 180 ℃ for 12 hours; wherein (a) is 1 μm; the graph (b) is 100nm.
FIG. 3 is an infrared spectrum of the prepared Si-GA.
FIG. 4 is a thermogravimetric test of Si-GA.
FIG. 5 is an electrochemical test of Si-GA; wherein (a) is a Cyclic Voltammogram (CV) of Si-GA at different scan rates; (b) The figure is a constant current charge-discharge curve (GCD) of Si-GA under different current densities; (c) the graph is a current density-specific capacitance curve of Si-GA; (d) Nyquist curve of Si-GA.
FIG. 6 is a test of the cycling stability of Si-GA after 1000 cycles at a current density of 10A/g.
[ detailed description ] embodiments
The invention is described in further detail below with reference to the accompanying drawings:
in the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention; the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; furthermore, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly and encompass, for example, both fixed and removable connections; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The invention discloses a silicon-doped graphene aerogel and a preparation method and application thereof, and the method comprises the following specific steps:
first step GO preparation: mixing 100-800 mg of natural graphite powder and 20mL of concentrated sulfuric acid, magnetically stirring for 30min, adding 0.5g of sodium nitrate to form a mixture A, wherein the mixture A is a graphite intercalation compound, slowly adding 3g of potassium permanganate after the mixture is cooled to 0 ℃, heating in a water bath to form a mixed slurry B, and heating in the water bath at 35-40 ℃ for 30min. 70mL of deionized water and 10mL of H were added 2 O 2 After the mixed solution is changed from brown to light yellow, forming a mixed solution C, washing the formed mixed solution C for dozens of times by using dilute hydrochloric acid, wherein the mass concentration of the dilute hydrochloric acid is 5%, adding the diluted hydrochloric acid, centrifuging at a high speed for 30min, removing residual acid, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3h to obtain uniform componentsThe GO is dispersed into GO dispersion liquid with different concentrations, and the concentration of the GO dispersion liquid prepared by strong oxidation of natural flake graphite by an improved Hummers method is 1-8 mg/mL.
The second step GA preparation: uniformly mixing 10ml of GO dispersion (2 mg/ml) and silicon dioxide accounting for 15% of the mass of the GO dispersion, transferring the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electric heating constant-temperature air blowing drying oven at 180 ℃, reacting for 12 hours, and taking out the reaction kettle after the reaction kettle is cooled to room temperature. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours at the temperature of 80 ℃, and then the Si-GA is obtained.
An application approach of the Si-GA provided by the invention is as follows: a super capacitor. The specific test process is as follows: a three-electrode system is adopted to test the electrochemical performance of Si-GA as a super capacitor electrode, a cyclic voltammetry curve under different scanning rates, a Si-GA constant current charging and discharging curve under different current densities, a current density-specific capacitance curve and a Nyquist curve.
The Si-GA provided by the invention can be used as a high-performance supercapacitor electrode, the energy band structure of graphene is adjusted through silicon doping, the performance of the graphene aerogel is further improved, and a good theoretical basis is provided for the application of the Si-GA in the field of supercapacitors. The preparation method of Si-GA provided by the invention has the advantages of simple synthesis method, low cost and industrialized production method. The invention will be described in more detail below with reference to the accompanying drawings and preferred embodiments of the invention.
Comparative example 1:
1) 200mg of natural graphite powder and 20mL of concentrated sulfuric acid are mixed, magnetically stirred for 30min, and then 0.5g of sodium nitrate is added. After the mixture is cooled to 0 ℃, 3g of potassium permanganate is slowly added, and the mixture is heated in a water bath at 40 ℃ for 30min to form mixed thick slurry. 70mL of deionized water and 10mL of H were then added 2 O 2 Washing the formed mixed solution with 1.0mol/L diluted hydrochloric acid, finally centrifuging at high speed, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3 hours to obtain 2mg/ml GO dispersion liquid.
2) Transferring GO dispersion liquid with the concentration of 2mg/ml to a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing, putting into an electrothermal constant-temperature air blowing drying box at 180 ℃, reacting for 12 hours, and taking out after the GO dispersion liquid is cooled to room temperature. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the graphene aerogel can be obtained.
The XRD pattern of the reaction product obtained in the comparative example is shown in fig. 1, the ir pattern is shown in fig. 3, and the thermogravimetric test is shown in fig. 4.
Example 1:
1) 100mg of natural graphite powder and 20mL of concentrated sulfuric acid are mixed, magnetically stirred for 30min, and then 0.5g of sodium nitrate is added.
After the mixture was cooled to 0c, 3g of potassium permanganate was slowly added,
2) Heating in water bath at 40 deg.C for 30min to obtain mixed thick paste. 70mL of deionized water and 10mL of H were added 2 O 2 The resulting mixed solution was washed with dilute hydrochloric acid, centrifuged at high speed, and the centrifuged solution was ultrasonically dispersed in deionized water for 3 hours to obtain a 1mg/mLGO dispersion.
2) Uniformly mixing GO dispersion liquid with the concentration of 1mg/ml and silicon dioxide with the mass of 15% of the GO dispersion liquid, transferring the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electric heating constant-temperature air blowing drying oven at 180 ℃, reacting for 12 hours, and taking out the reaction kettle after the reaction kettle is cooled to room temperature. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the Si-GA is obtained.
Example 2:
1) 200mg of natural graphite powder and 20ml of concentrated sulfuric acid are mixed, magnetically stirred for 30min and then 0.5g of sodium nitrate is added. After the mixture is cooled to 0 ℃, 3g of potassium permanganate is slowly added, and the mixture is heated in a water bath at 35 ℃ for 30min to form mixed thick slurry. 70ml of deionized water and 15ml of H were added 2 O 2 Washing the formed mixed solution with dilute hydrochloric acid, centrifuging at high speed, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3 hours to obtain GO dispersion liquid with the concentration of 2 mg/ml.
2) Uniformly mixing GO dispersion liquid with the concentration of 2mg/ml and 15wt% of silicon dioxide, transferring the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electrothermal constant-temperature air blowing drying oven at 180 ℃, reacting for 12 hours, cooling the reaction kettle to room temperature, and taking the reaction kettle out. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the Si-GA is obtained.
The XRD pattern and SEM morphology of the reaction product obtained in example 2 are shown in FIG. 1 and FIG. 2, and Si-GA has a three-dimensional well-defined and interconnected pore structure. The Si-GA lamellar is completely and effectively stacked, holes of the Si-GA with clear boundaries are between several microns and dozens of nanometers, the three-dimensional structure with obvious levels and mutual communication not only prevents the graphene lamellar from agglomerating in a large range, but also increases the specific surface area of the graphene lamellar. As shown in FIG. 3, the GO and Si-GA are characterized in 500-4000cm by FT-IR -1 The distribution of the internal functional groups shows that the strength of O-H bonds and alkoxy C-O bonds is greatly reduced, and C = O bonds of carboxyl groups and carbonyl groups are completely disappeared, which indicates that a large amount of oxygen-containing functional groups are decomposed in the hydrothermal process. The enhancement of the aromatic C = C bond absorption peak indicates the repair of most graphitic regions of Si-GA.
Referring to fig. 4, which is a thermogravimetric side view, TGA test results of GO and Si-GA at 50-1000 ℃ show that decomposition of some of the remaining oxygen-containing functional groups, scavenging a substantial amount of the oxygen-containing functional groups in Si-GA during hydrothermal reduction, showing that Si-GA possesses better thermal stability than GO, and fig. 4 is a thermogravimetric test plot. FIG. 5 (a) is a graph of Cyclic Voltammograms (CVs) of Si-GA at various scan rates, with the CV curves being rectangular-like in shape at all scan rates and the maximum wrap area of the CV curves at 100mV/s scan rate representing the maximum specific capacitance. FIG. 5 (b) is a graph of Si-GA constant current charge and discharge curves (GCD) at different current densities, all the GCD curves are isosceles triangles, no obvious potential drop is generated, and the specific capacitance of Si-GA as the electrode material of the super capacitor is up to 348.5F/g at a current density of 1A/g. FIG. 5 (c) is a graph showing current density-specific capacitance curves for Si-GA, showing that Si-GA has good rate properties, and these excellent properties are likely due to the large specific surface area and good wettability of Si-GA material to provide channels for electrolyte ion transport. FIG. 5 (d) is a Nyquist plot for Si-GA, showing accurate doping of the Si element, and Si-GA exhibits a lower combined internal resistance, indicating good pure capacitance behavior of Si-GA. Referring to FIG. 6, a cyclic stability test is performed to test the cyclic stability of Si-GA at a high current density of 10A/g after 1000 charge-discharge cycles. The result shows that the capacitance retention rate of Si-GA is 95.71%, and the good cycling stability is shown.
Example 3:
1) 300mg of natural graphite powder and 20ml of concentrated sulfuric acid are mixed, magnetically stirred for 30min and then 0.5g of sodium nitrate is added. After the mixture is cooled to 0 ℃, 3g of potassium permanganate is slowly added, and the mixture is heated in a water bath at 38 ℃ for 30min to form mixed thick slurry. 70mL of deionized water and 1mLH were added 2 O 2 Washing the formed mixed solution with dilute hydrochloric acid, centrifuging at high speed, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3 hours to obtain GO dispersion liquid with the degree of 3 mg/ml.
2) Uniformly mixing 3mg/ml GO dispersion liquid and 15wt% of silicon dioxide, transferring the mixture to a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electrothermal constant-temperature air blowing drying box at 180 ℃, reacting for 12 hours, cooling the reaction kettle to room temperature, and taking the reaction kettle out. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the Si-GA is obtained.
Example 4:
1) 400mg of natural graphite powder and 20mL of concentrated sulfuric acid are mixed, magnetically stirred for 30min, and then 0.5g of sodium nitrate is added. After the mixture is cooled to 0 ℃, 3g of potassium permanganate is slowly added, and the mixture is heated in water bath at 37 ℃ for 30min to form mixed thick slurry. 70mL of deionized water and 10mLH were added 2 O 2 Washing the formed mixed solution with dilute hydrochloric acid, centrifuging at a high speed, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3 hours to obtain GO dispersion liquid.
2) Uniformly mixing GO dispersion liquid with the concentration of 4mg/ml and 15wt% of silicon dioxide, transferring the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electrothermal constant-temperature air blowing drying box at 180 ℃, reacting for 12 hours, cooling the reaction kettle to room temperature, and taking out the reaction kettle. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the Si-GA is obtained.
Example 5:
1) 500mg of natural graphite powder and 20mL of concentrated sulfuric acid are mixed, magnetically stirred for 30min and then added with sodium nitrate. After the mixture was cooled to 0 ℃ 3g potassium permanganate and 39 ℃ water were slowly addedThe bath is heated for 30min to form a mixed thick paste. 70mL of deionized water and 10mLH were added 2 O 2 And washing the formed mixed solution by using dilute hydrochloric acid, centrifuging at a high speed, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3 hours to obtain a GO dispersion liquid.
2) Uniformly mixing GO dispersion liquid with the concentration of 5mg/ml and 15wt% of silicon dioxide, transferring the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electrothermal constant-temperature air blowing drying oven at 180 ℃, reacting for 12 hours, cooling the reaction kettle to room temperature, and taking the reaction kettle out. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the Si-GA is obtained.
Example 6:
1) 600mg of natural graphite powder and 20mL of concentrated sulfuric acid are mixed, magnetically stirred for 30min, and then 0.5g of sodium nitrate is added. After the mixture is cooled to 0 ℃, 3g of potassium permanganate is slowly added, and the mixture is heated in a water bath at 36 ℃ for 30min to form mixed thick slurry. 70mL of deionized water and 15mLH were added 2 O 2 And washing the formed mixed solution by using dilute hydrochloric acid, centrifuging at a high speed, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3 hours to obtain a GO dispersion liquid.
2) Uniformly mixing GO dispersion liquid with the concentration of 6mg/ml and 15wt% of silicon dioxide, transferring the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electrothermal constant-temperature air blowing drying oven with the temperature of 180 ℃, reacting for 12 hours, cooling the reaction kettle to room temperature, and taking the reaction kettle out. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the Si-GA is obtained.
Example 7:
1) 700mg of natural graphite powder and 520mL of concentrated sulfuric acid are mixed, and 0.5g of sodium nitrate is added after magnetic stirring for 30min. After the mixture is cooled to 0 ℃, 3g of potassium permanganate is slowly added, and the mixture is heated in water bath at 37 ℃ for 30min to form mixed thick slurry. 70mL of deionized water and 10mLH were added 2 O 2 Washing the formed mixed solution with dilute hydrochloric acid, centrifuging at a high speed, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3 hours to obtain GO dispersion liquid.
2) Uniformly mixing 7mg/ml GO dispersion liquid and 15wt% silicon dioxide, transferring the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electrothermal constant-temperature air blowing drying oven at 180 ℃, reacting for 12 hours, cooling the reaction kettle to room temperature, and taking the reaction kettle out. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the Si-GA is obtained.
Example 8:
1) 800mg of natural graphite powder and 20mL of concentrated sulfuric acid are mixed, magnetically stirred for 30min, and then 0.5g of sodium nitrate is added. After the mixture is cooled to 0 ℃, 3g of potassium permanganate is slowly added, and the mixture is heated in a water bath at 38 ℃ for 30min to form mixed thick slurry. 70mL of deionized water and 10mLH were added 2 O 2 And washing the formed mixed solution by using dilute hydrochloric acid, centrifuging at a high speed, and ultrasonically dispersing the centrifugally washed solution in deionized water for 3 hours to obtain a GO dispersion liquid.
2) Uniformly mixing GO dispersion liquid with the concentration of 8mg/ml and 15wt% of silicon dioxide, transferring the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene lining, sealing the reaction kettle, putting the reaction kettle into an electrothermal constant-temperature air blowing drying oven at 180 ℃, reacting for 12 hours, cooling the reaction kettle to room temperature, and taking the reaction kettle out. And after the surface of the graphene is naturally aired, vacuum drying is carried out for 72 hours, and then the Si-GA is obtained.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (6)

1. The application of the silicon-doped graphene aerogel in the field of capacitors is characterized in that the graphene aerogel is formed by winding lamellar graphene sheets, three-dimensional holes are formed among the wound graphene sheets, silicon atoms are doped in the holes, and the size of the holes is 1 mu m-100nm;
the preparation method of the silicon-doped graphene aerogel comprises the following steps:
step 1, mixing natural graphite powder and concentrated sulfuric acid, adding sodium nitrate after stirring to form a mixture A, cooling the mixture A to 0 ℃, adding potassium permanganate, and heating in a water bath to form a slurry B; the water bath heating temperature is 35-40 ℃, and the water bath heating time is 30min;
step 2, adding deionized water and H into the slurry B 2 O 2 Washing the mixed solution C by dilute hydrochloric acid after the mixture is changed from brown to light yellow, centrifuging the washed mixed solution C, and ultrasonically dispersing the centrifuged solution in water to obtain GO dispersion liquid;
step 3, mixing the GO dispersion liquid and silicon dioxide, carrying out hydrothermal reaction, airing a product, and carrying out vacuum drying to obtain silicon-doped graphene aerogel; the hydrothermal reaction temperature is 180 ℃, and the hydrothermal reaction time is 12h.
2. The application of the silicon-doped graphene aerogel in the field of capacitors as claimed in claim 1, wherein in the step 1, the mixing ratio of the natural graphite powder to the concentrated sulfuric acid is 1g:23mL, 0.5g of sodium nitrate was added.
3. The application of the silicon-doped graphene aerogel in the field of capacitors according to claim 1, wherein 3g of potassium permanganate is added to 1g of natural graphene powder in step 1.
4. The application of the silicon-doped graphene aerogel in the field of capacitors as claimed in claim 1, wherein in the step 2, the ultrasonic dispersion time is 3h, and the concentration of the GO dispersion liquid is 1-8 mg/mL.
5. The application of the silicon-doped graphene aerogel in the field of capacitors as claimed in claim 1, wherein in the step 3, the mass of the added silicon dioxide is 15% of the mass of the GO dispersion liquid.
6. The application of the silicon-doped graphene aerogel in the field of capacitors as claimed in claim 1, wherein in step 3, the vacuum drying time is 72h.
CN202011325444.4A 2020-11-23 2020-11-23 Silicon-doped graphene aerogel and preparation method and application thereof Active CN112479188B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011325444.4A CN112479188B (en) 2020-11-23 2020-11-23 Silicon-doped graphene aerogel and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011325444.4A CN112479188B (en) 2020-11-23 2020-11-23 Silicon-doped graphene aerogel and preparation method and application thereof

Publications (2)

Publication Number Publication Date
CN112479188A CN112479188A (en) 2021-03-12
CN112479188B true CN112479188B (en) 2023-02-28

Family

ID=74933159

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011325444.4A Active CN112479188B (en) 2020-11-23 2020-11-23 Silicon-doped graphene aerogel and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN112479188B (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104860304A (en) * 2015-05-07 2015-08-26 中国人民解放军国防科学技术大学 High specific surface area of silicon oxide hybridized graphene aerogel and production method thereof
CN105217640A (en) * 2015-08-20 2016-01-06 西南交通大学 The preparation method of a kind of graphene oxide/SiO 2 hybrid aerogel
WO2016037565A1 (en) * 2014-09-11 2016-03-17 中国科学院上海应用物理研究所 Graphene hydrogel and graphene aerogel as well as preparation methods therefor and applications thereof
CN107235744A (en) * 2017-06-02 2017-10-10 东南大学 A kind of preparation method of graphene aerosil
CN109904415A (en) * 2019-01-25 2019-06-18 武汉科技大学 A kind of nano-silicon-graphene aerogel is composite porous and preparation method thereof
CN110833799A (en) * 2019-11-04 2020-02-25 江苏一夫新材料产业技术研究院有限公司 Graphene-elemental silicon composite aerogel and preparation method thereof
CN111498839A (en) * 2020-04-29 2020-08-07 青岛科技大学 Ultrathin sheet layer reduced graphene oxide and synthesis method thereof

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8993113B2 (en) * 2010-08-06 2015-03-31 Lawrence Livermore National Security, Llc Graphene aerogels

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016037565A1 (en) * 2014-09-11 2016-03-17 中国科学院上海应用物理研究所 Graphene hydrogel and graphene aerogel as well as preparation methods therefor and applications thereof
CN104860304A (en) * 2015-05-07 2015-08-26 中国人民解放军国防科学技术大学 High specific surface area of silicon oxide hybridized graphene aerogel and production method thereof
CN105217640A (en) * 2015-08-20 2016-01-06 西南交通大学 The preparation method of a kind of graphene oxide/SiO 2 hybrid aerogel
CN107235744A (en) * 2017-06-02 2017-10-10 东南大学 A kind of preparation method of graphene aerosil
CN109904415A (en) * 2019-01-25 2019-06-18 武汉科技大学 A kind of nano-silicon-graphene aerogel is composite porous and preparation method thereof
CN110833799A (en) * 2019-11-04 2020-02-25 江苏一夫新材料产业技术研究院有限公司 Graphene-elemental silicon composite aerogel and preparation method thereof
CN111498839A (en) * 2020-04-29 2020-08-07 青岛科技大学 Ultrathin sheet layer reduced graphene oxide and synthesis method thereof

Also Published As

Publication number Publication date
CN112479188A (en) 2021-03-12

Similar Documents

Publication Publication Date Title
Mi et al. A self-sacrifice template strategy to fabricate yolk-shell structured silicon@ void@ carbon composites for high-performance lithium-ion batteries
Geng et al. Facile synthesis of B/N co-doped 2D porous carbon nanosheets derived from ammonium humate for supercapacitor electrodes
CN113299896B (en) Preparation method and application of hollow porous silicon-carbon @ lignin-carbon nanospheres
Zhao et al. Preparation of hierarchical graphdiyne hollow nanospheres as anode for lithium-ion batteries
Xiao et al. Balancing crystallinity and specific surface area of metal-organic framework derived nickel hydroxide for high-performance supercapacitor
Zou et al. Microwave-assisted preparation of hollow porous carbon spheres and as anode of lithium-ion batteries
CN112390249A (en) Boron-doped graphene aerogel and preparation method and application thereof
Wang et al. Chemoselective solution synthesis of pyrazolic-structure-rich nitrogen-doped graphene for supercapacitors and electrocatalysis
Zhang et al. Optimizing crystallinity and porosity of hierarchical Ni (OH) 2 through conformal transformation of metal–organic framework template for supercapacitor applications
Lin et al. In-situ pre-lithiated onion-like SiOC/C anode materials based on metallasilsesquioxanes for Li-ion batteries
Qi et al. Sandwich-structured nanocomposites of N-doped graphene and nearly monodisperse Fe 3 O 4 nanoparticles as high-performance Li-ion battery anodes
Zhang et al. Synthesis and characterization of metal–organic framework/biomass-derived CoSe/C@ C hierarchical structures with excellent sodium storage performance
Yang et al. Controllable crystal growth of a NiCo-LDH nanostructure anchored onto KCu 7 S 4 nanowires via a facile solvothermal method for supercapacitor application
WO2021196430A1 (en) Lithium-ion battery negative electrode material and preparation method therefor
Chen et al. Self-propelled nanoemulsion assembly of organosilane to the synthesis of high-surface-area hollow carbon spheres for enhanced energy storage
CN111243871B (en) Novel NiSe2Coated mesoporous hollow carbon sphere composite material, preparation method thereof and application thereof in super capacitor
Ma et al. Converting micro-sized kerf-loss silicon waste to high-performance hollow-structured silicon/carbon composite anodes for lithium-ion batteries
CN106848282B (en) Negative electrode material for non-aqueous electrolyte secondary battery and preparation method and application thereof
CN110085823B (en) Nano composite negative electrode material and preparation method and application thereof
Liu et al. Confined self-assembly of SiOC nanospheres in graphene film to achieve cycle stability of lithium ion batteries
Yang et al. Preparation of super thin and defect rich graphene shell and its application for high performance supercapacitor electrode and novel ORR catalyst support
Li et al. Recent discovery of a multifunctional metallo-organic precursor for fabricating Co 3 O 4/N-doped porous carbon by one-step in situ pyrolysis as an anode material for Li-ion batteries
KR101725965B1 (en) Carbon-coated mesoporous SiOx particles for high-capacity lithium storage material and preparation method thereof
CN113461016A (en) Silicon-carbon negative electrode material and preparation method and application thereof
CN113241260A (en) Preparation method and application of hollow hyperbranched carbon material

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