CN113148994B - Graphene and preparation method and application thereof - Google Patents
Graphene and preparation method and application thereof Download PDFInfo
- Publication number
- CN113148994B CN113148994B CN202110545312.0A CN202110545312A CN113148994B CN 113148994 B CN113148994 B CN 113148994B CN 202110545312 A CN202110545312 A CN 202110545312A CN 113148994 B CN113148994 B CN 113148994B
- Authority
- CN
- China
- Prior art keywords
- graphene
- magnesium carbonate
- template
- fluidized bed
- carbon source
- 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
-
- 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
- C01B32/186—Preparation by chemical vapour deposition [CVD]
-
- 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
- H01G11/26—Electrodes characterised by their structure, e.g. multi-layered, porosity or surface features
-
- 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
- C01B2204/22—Electronic 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
- C01B2204/32—Size or surface area
Abstract
The invention provides graphene and a preparation method and application thereof, wherein the preparation method comprises the following steps: (1) Preparing a compound of graphene and a template agent by using magnesium carbonate as the template agent and adopting a fluidized bed chemical vapor deposition method; (2) Removing the template agent in the compound of the graphene and the template agent in an acid washing mode to obtain the graphene; (3) And (3) adding a carbonate aqueous solution into the filtrate after the acid washing, obtaining magnesium carbonate through regeneration, and circulating the magnesium carbonate obtained after the regeneration to the step (1) to be used as a template agent so as to continuously prepare the graphene. The method provided by the invention is easy to control, low in operation cost and simple in process, not only can realize recycling of the template agent, but also can realize batch preparation of graphene by using a fluidized bed chemical vapor deposition method, and further can greatly reduce the production cost of the graphene.
Description
Technical Field
The invention relates to graphene and a preparation method and application thereof, in particular to a method for preparing graphene by using magnesium carbonate as a template and adopting a fluidized bed chemical vapor deposition method, and belongs to the technical field of nano composite materials.
Background
In 2004, geim et al successfully produced graphene by mechanical exfoliation (Science 2004;306 (5696): 666-9). Graphene, as a novel carbon material with a two-dimensional structure, has excellent physical and chemical properties. Graphene exists in a two-dimensional crystal structure, the thickness of which is only that of a monolayer of carbon atoms. The graphene material has the excellent properties of high thermal conductivity, high strength and large specific surface area, and the properties enable the graphene to have good application prospects in the fields of energy storage, sensors and the like.
The preparation method of the graphene mainly comprises a mechanical stripping method, a chemical vapor deposition method, an oxidation-reduction method, an epitaxial growth method and the like. Geim et al used ion beam etching to etch the surface of a 1mm thick oriented pyrolytic graphite sheet, adhered both sides of the sheet with a custom made tape, and repeated mechanical exfoliation to obtain graphene with a single layer of carbon atoms thickness (Science 2004 (5696): 666-9). The graphene prepared by the method has high quality, but has certain limitation on realizing the batch preparation of the graphene. The redox method is also the predominant method currently used for preparing graphene, with the Hummers method and the modified Hammers method being most widely used (Journal of the American Chemical Society 1958 (6): 1339. However, the redox method requires the use of a strong oxidant in the preparation process, and has a severe preparation process and high operation cost. The epitaxial growth method comprises the steps of firstly growing graphene on a substrate, and then removing the substrate to obtain the graphene with the size similar to that of the original substrate. The graphene prepared by the method has high quality, but is not suitable for batch preparation. The chemical vapor deposition method is an effective method for producing graphene in batches, and the production process is simple and controllable. In the process, no catalyst is required to be introduced, and carbon deposition is generally carried out on the surface of the template. The chemical vapor deposition method has the advantage that the graphene can be produced in batches, but a template which is low in price and easy to remove is selected.
Growth of few-layer graphene on nickel or copper films can be achieved using Chemical vapor deposition (Accounts of Chemical Research 2013. However, the method of growing graphene on a nickel or copper film has a low yield of graphene and is difficult to mass-produce. The powder metal oxide template is adopted to replace a metal film, the fluidized bed process is matched, and the template removing agent is washed away by acid to obtain the powder graphene, so that the yield of the graphene can be obviously improved. However, in the process of preparing graphene by using a metal oxide as a template, the template is used only once, which increases the production cost of graphene. Therefore, recycling of the templating agent is critical.
Therefore, providing a novel graphene preparation method has become a technical problem to be solved urgently in the field.
Disclosure of Invention
In order to solve the above disadvantages and shortcomings, an object of the present invention is to provide a method for preparing graphene.
Another object of the present invention is to provide graphene prepared by the above method for preparing graphene.
The invention also aims to provide application of the graphene as an electrode material of a supercapacitor.
Another object of the present invention is to provide a supercapacitor, wherein an electrode material of the supercapacitor is the graphene described above.
In order to achieve the above object, in one aspect, the present invention provides a method for preparing graphene, comprising the steps of:
(1) Preparing a compound of graphene and a template agent by using magnesium carbonate as the template agent and adopting a fluidized bed chemical vapor deposition method;
(2) Removing the template agent in the compound of the graphene and the template agent in an acid washing mode to obtain the graphene;
(3) And (2) adding a carbonate aqueous solution into the filtrate after the acid washing, obtaining magnesium carbonate through regeneration, and circulating the magnesium carbonate obtained after the regeneration to the step (1) to be used as a template agent so as to continuously prepare the graphene.
As a specific embodiment of the above method of the present invention, wherein the step (3) comprises the following specific steps:
and (2) adding a carbonate aqueous solution into the filtrate after acid washing according to the molar ratio of 1.
The carbonate may be sodium carbonate, for example.
In the method provided by the invention, the shape and size of the template can obviously influence the performance of the finally prepared graphene, and the magnesium carbonate template used by the method can effectively inhibit the stacking of the graphene, so that the graphene with excellent performance is prepared.
In a specific embodiment of the invention, the compound of graphene and the template is washed by an acid solution, the template is removed, and then the filter cake is dried to obtain the graphene.
In a specific embodiment of the invention, in the regeneration process of the magnesium carbonate template, a system obtained after reaction is kept still for a period of time, the obtained system is filtered, and then a solid product obtained after reaction is dried to obtain the regenerated magnesium carbonate template.
The characterization verifies that the microscopic morphology and performance of the regenerated magnesium carbonate template are the same as those of the original template, and further the regenerated magnesium carbonate template can be adopted to continue the preparation of the graphene.
As a specific embodiment of the above method of the present invention, the magnesium carbonate includes one or a combination of several of rod-shaped magnesium carbonate, flower-shaped hollow tube magnesium carbonate, or rose-shaped magnesium carbonate.
In a specific embodiment of the invention, the width of the rod-shaped magnesium carbonate is 0.1-0.5 μm, the length range is 10-30 μm, and the length-diameter ratio is 20-60.
In one embodiment of the present invention, the magnesium carbonate of the flower-shaped hollow tube has a width of 0.5-1 μm, a length of 5-30 μm, and an aspect ratio of 10-30.
In a specific embodiment of the invention, the diameter of the rosette-shaped magnesium carbonate is 2 μm.
As a specific embodiment of the above method of the present invention, the magnesium carbonate is prepared by the following steps:
adding a sodium carbonate aqueous solution into a magnesium chloride aqueous solution, stirring and reacting for 0.5-6h in a water bath at the temperature of 20-80 ℃, and drying a solid product obtained by the reaction to obtain the magnesium carbonate.
Adding a sodium carbonate aqueous solution into a magnesium chloride aqueous solution, stirring and reacting for 0.5-6h in a water bath at the temperature of 20-80 ℃, and drying a solid product obtained by the reaction to obtain the magnesium carbonate, wherein the magnesium carbonate comprises but is not limited to one or the combination of more of rod-shaped magnesium carbonate, flower-shaped hollow tube magnesium carbonate or rose-shaped magnesium carbonate; in the prior art, magnesium carbonate prepared by hydrothermal reaction (the temperature is usually 100-200 ℃) is in a granular state with a random morphology, and the magnesium carbonate prepared by the two methods has obvious difference in morphology and size.
In one embodiment of the above method of the present invention, the concentrations of the aqueous sodium carbonate solution and the aqueous magnesium chloride solution are both 0.1 to 1mol/L.
In one embodiment of the above method of the present invention, the concentrations of the aqueous sodium carbonate solution and the aqueous magnesium chloride solution are both 0.5mol/L.
As a specific embodiment of the above method of the present invention, wherein the reaction time is 1 hour.
The drying can be performed by adopting the conventional operation in the field, and as a specific embodiment of the method, the drying is performed at 100 ℃ for 2-24h.
In the invention, sodium carbonate and magnesium chloride are used as raw materials, a magnesium carbonate precipitate is prepared by adopting an induced crystallization coupling auxiliary precipitation method, and the magnesium carbonate template agent is obtained after filtering and drying operations.
As a specific embodiment of the above method of the present invention, wherein the fluidized bed chemical vapor deposition method comprises the steps of:
and introducing carrier gas into the fluidized bed reactor, heating the fluidized bed reactor to the reaction temperature, adding a magnesium carbonate template into the fluidized bed reactor, roasting for a period of time, introducing a carbon source gas into the fluidized bed reactor to enable the carbon source gas to perform deposition reaction on the roasted magnesium carbonate template, and obtaining the graphene/template compound after the reaction is finished.
Aiming at the outstanding problems of harsh operating conditions, low yield, high cost and the like in the graphene preparation process, the graphene is prepared by taking magnesium carbonate as a template agent and adopting a fluidized bed chemical vapor deposition method, and in the preparation process, the high fluidization of the magnesium carbonate in a fluidized bed reactor and the efficient heat and mass transfer between reaction gas (carbon source gas) and the template agent are all beneficial to the rapid, uniform and stable growth of the graphene, so that the high quality of the graphene is ensured; meanwhile, the high-throughput fluidized bed process can also obviously improve the production of the powder graphene. Therefore, the method provided by the invention has the advantages of both the quality and the yield of the graphene.
As a specific implementation mode of the method, the roasting temperature is 600-900 ℃, and the roasting time is 10-60min.
In one embodiment of the above method of the present invention, the firing temperature is 700 ℃.
As a specific embodiment of the above method of the present invention, wherein the reaction temperature is 600-1000 deg.C, the reaction pressure is 0.1-0.15MPa, and the reaction time is 5-100min.
As a specific embodiment of the above method of the present invention, wherein the reaction temperature is 600-900 ℃ and the reaction time is 10-30min.
In an embodiment of the above method of the present invention, the carrier gas and the carbon source gas have a gas velocity of 0.001 to 1m/s, respectively.
In an embodiment of the above method of the present invention, the carrier gas and the carbon source gas have a gas velocity of 0.005-0.1m/s, respectively.
In an embodiment of the above method of the present invention, the carbon source gas used in the fluidized bed chemical vapor deposition method includes one or a combination of several of methane, ethane, ethylene, acetylene, and propane.
In an embodiment of the above method, the carbon source gas is methane, ethylene or acetylene.
In an embodiment of the above method of the present invention, the carrier gas used in the fluidized bed chemical vapor deposition method includes one or a combination of nitrogen, argon and helium.
As an embodiment of the above method of the present invention, wherein a molar ratio of the carrier gas to the carbon source gas is 0.1 to 10.
As an embodiment of the above method of the present invention, wherein a molar ratio of the carrier gas to the carbon source gas is 0.5 to 2.
In one embodiment of the invention, a magnesium carbonate template is added from above the fluidized bed reactor.
In a specific embodiment of the invention, after the reaction is finished, after the temperature of the fluidized bed reactor is naturally reduced to room temperature, taking out the compound of the graphene and the template agent;
and calculating the required acid amount, carrying out acid washing purification on the compound of the graphene and the template agent, then washing with water, washing the product to be neutral, and drying to obtain the graphene.
In the invention, the acid solution used for acid washing can be a hydrochloric acid aqueous solution which is conventional in the field, the specific concentration of the acid solution has no influence on the achievement of the purpose of the invention, and the concentration can be reasonably set by a person skilled in the art according to the actual operation requirement on the field.
On the other hand, the invention also provides the graphene prepared by the preparation method of the graphene.
In an embodiment of the graphene of the present invention, the specific surface area of the graphene is 1500-2000m 2 The pore size distribution range is 2-10nm.
In another aspect, the invention also provides an application of the graphene as an electrode material of a supercapacitor.
In another aspect, the invention further provides a supercapacitor, wherein an electrode material of the supercapacitor is the graphene.
According to the invention, the graphene is prepared by adopting a fluidized bed chemical vapor deposition method, the preparation process is easy to control, the operation cost is low, the process is simple, the cyclic utilization of the template agent can be realized, the batch preparation of the graphene by adopting the fluidized bed chemical vapor deposition method can also be realized, and the production cost of the graphene can be greatly reduced.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.
FIG. 1a is a scanning electron micrograph of a bar-shaped magnesium carbonate template prepared in example 1 of the present invention.
FIG. 1b is a scanning electron microscope image of porous magnesium oxide obtained by calcining the rod-shaped magnesium carbonate template prepared in example 1 of the present invention at 900 ℃ for 20 min.
FIG. 2 is a pore size distribution curve of porous magnesium oxide obtained by calcining a bar-shaped magnesium carbonate template prepared in example 1 of the present invention at 900 ℃ for 20 min.
Fig. 3a is an adsorption-desorption curve of graphene prepared in step 3 of example 1 of the present invention.
Fig. 3b is a pore distribution curve of graphene prepared in step 3 of example 1 of the present invention.
Fig. 4 is a scanning electron micrograph of graphene prepared in step 3 of example 1 according to the present invention.
FIG. 5 is a scanning electron microscope image of a bar-shaped magnesium carbonate template obtained after regeneration in step 4 of example 1 of the present invention.
Fig. 6 is a scanning electron micrograph of graphene prepared in step 5 of example 1 according to the present invention.
FIG. 7 is a scanning electron microscope image of a magnesium carbonate template agent of flower-shaped hollow tube prepared in example 5 of the present invention.
FIG. 8 is a scanning electron microscope image of magnesium carbonate template agent of flower-shaped hollow tube obtained after regeneration in step 4 of example 5.
FIG. 9 is a scanning electron micrograph of rosette magnesium carbonate prepared in example 6 of the present invention.
Fig. 10 is a CV curve of the initial graphene obtained in example 1 in application example 1 of the present invention applied to a supercapacitor electrode material.
Fig. 11 is a CV curve of the regenerated graphene obtained in example 1 applied to an electrode material of a supercapacitor in application example 1 of the present invention.
Fig. 12 is a CV curve of the initial graphene and the regenerated graphene obtained in example 5 applied to an electrode material of a supercapacitor in application example 2 of the present invention.
Fig. 13 is a GCD curve of the application example 2 of the present invention when the initial graphene and the regenerated graphene obtained in example 5 are applied to a supercapacitor electrode material.
Detailed Description
The technical solutions of the present invention will be described in detail with reference to the following specific examples in order to clearly understand the technical features, objects and advantages of the present invention, but the present invention should not be construed as being limited to the implementable scope of the present invention.
Example 1
The embodiment provides a method for preparing graphene by adopting a fluidized bed chemical vapor deposition method, which comprises the following steps:
step 1: preparation of magnesium carbonate template agent with rod-like appearance
Adding 100mL of sodium carbonate aqueous solution (the concentration is 0.5 mol/L) into 100mL of magnesium chloride aqueous solution (the concentration is 0.5 mol/L), stirring and reacting for 1h in a room-temperature water bath, and drying a solid product obtained by the reaction at 100 ℃ for 2-24h to obtain the rod-shaped magnesium carbonate; the width of the bar-shaped magnesium carbonate is 0.1-0.5 μm, the length is in the range of 10-30 μm, and the length-diameter ratio is 20-60, and the data of the width, the length and the length-diameter ratio of the bar-shaped magnesium carbonate can be known from the following figure 1 a;
step 2: introducing argon into a vertical fluidized bed reactor at a rate of 0.4L/min, heating the vertical fluidized bed reactor to 900 ℃ at a heating rate of 15 ℃/min, operating the vertical fluidized bed reactor under a normal pressure condition, adding a rodlike magnesium carbonate template into the vertical fluidized bed reactor, roasting for 20min, introducing methane gas flow into the vertical fluidized bed reactor at a rate of 0.4L/min for 15min, enabling the molar ratio of argon to methane to be 1, and enabling methane to perform a deposition reaction on the roasted rodlike magnesium carbonate template, wherein the reaction temperature is 900 ℃, the pressure is 0.1MPa, the time is 15min, and after the reaction is finished, obtaining a compound of graphene and the template;
and step 3: naturally cooling the vertical fluidized bed reactor to room temperature, taking out the compound of the graphene and the template agent, pickling the compound of the graphene and the template agent by using a hydrochloric acid solution to remove the template agent, washing the compound of the graphene and the template agent to be neutral by using deionized water, and drying the compound of the graphene and the template agent for 24 hours at 100 ℃ to obtain the graphene;
and 4, step 4: regeneration of rod-shaped magnesium carbonate template agent
Collecting the filtrate after acid washing, adding a sodium carbonate aqueous solution into the filtrate after acid washing according to the molar ratio of sodium carbonate to magnesium chloride of 1;
and 5: and (4) circulating the regenerated rodlike magnesium carbonate template agent to the step (1) to continue producing the graphene.
The scanning electron microscope images of the rod-shaped magnesium carbonate template prepared in the example and the scanning electron microscope images of the porous magnesium oxide obtained after the rod-shaped magnesium carbonate template is calcined at 900 ℃ for 20min are respectively shown in FIG. 1a and FIG. 1 b. As is evident from FIG. 1a, the magnesium carbonate produced in this example is indeed a rod-like structure; as can be seen from FIG. 1b, the porous magnesium oxide obtained by calcining the rod-like magnesium carbonate prepared in this example at 900 ℃ for 20min has a three-dimensional porous structure.
The pore size distribution curve of the porous magnesium oxide obtained by calcining the rod-shaped magnesium carbonate template prepared in example 1 at 900 ℃ for 20min is shown in FIG. 2. It can be seen from fig. 2 thatThe porous magnesium oxide has a peak value at 4-8nm in the pore distribution curve, the pore diameter is distributed between 1-100nm, and the specific surface area of the porous magnesium oxide is 98m 2 /g。
The adsorption-desorption curve and the pore distribution curve of the graphene prepared in step 3 of this example 1 are shown in fig. 3a and 3b, respectively. As can be seen from FIGS. 3a and 3b, the specific surface area of the graphene prepared by using methane as a carbon source is 1292m 2 The absorption and desorption isotherm of the molecular sieve belongs to an H2 type hysteresis loop (according to the classification of IUPAC (International Union of theory and applied chemistry)), the pore distribution curve has a peak value between 3 and 4nm, and the pore size distribution curve has a peak value between 1 and 100 nm.
Fig. 4 shows a scanning electron microscope image of the graphene prepared in step 3 of this embodiment 1, and it can be seen from fig. 4 that the graphene prepared by using a rod-like magnesium carbonate as a template in this embodiment perfectly maintains a three-dimensional rod-like morphology of the magnesium carbonate template, and as a result, the graphene prepared by using a fluidized bed chemical vapor deposition method in this embodiment can well maintain the morphology of the template used.
In this example 1, a scanning electron microscope image of the rod-shaped magnesium carbonate template obtained after the regeneration in step 4 is shown in fig. 5, and comparing fig. 5 with fig. 1a, it can be seen that the magnesium carbonate obtained after the regeneration in step 4 has the same micro morphology as the initial magnesium carbonate prepared in step 1, that is, the morphology of the magnesium carbonate obtained after the regeneration in step 4 is also an obvious rod shape, which proves the feasibility of the template regeneration method provided in the embodiment of the present invention.
In this example 1, a scanning electron microscope image of the graphene obtained in step 5 is shown in fig. 6, and as can be seen by comparing fig. 6 and fig. 4, the graphene obtained in step 5 by using the bar-shaped magnesium carbonate obtained after regeneration as a template has the same microscopic morphology as the graphene obtained in step 3 by using the original bar-shaped magnesium carbonate (i.e., the magnesium carbonate obtained in step 1) as a template, which further illustrates the feasibility of the template regeneration method provided in the embodiment of the present invention.
Example 2
This example provides a method for preparing graphene by fluidized bed chemical vapor deposition, which is different from example 1 only in that:
the carbon source gas is ethylene, and the roasting temperature and the reaction temperature are both 680 ℃.
In this example, the porous magnesium oxide obtained by calcining rod-like magnesium carbonate at 680 ℃ for 20min also had a three-dimensional porous structure.
In this embodiment, the graphene prepared by using the bar-shaped magnesium carbonate as the template agent perfectly maintains the three-dimensional bar-shaped morphology of the magnesium carbonate template agent.
In this embodiment, the magnesium carbonate obtained after the regeneration in step 4 has the same micro morphology as the initial magnesium carbonate prepared in step 1, that is, the morphology of the magnesium carbonate obtained after the regeneration in step 4 is also an obvious rod shape, which actually illustrates the feasibility of the template regeneration method provided in the embodiment of the present invention.
In this embodiment, the graphene prepared by using ethylene as a carbon source gas and using the rod-shaped magnesium carbonate obtained after regeneration as a template in step 5 has the same micro morphology as the graphene prepared by using ethylene as a carbon source gas and using the initial rod-shaped magnesium carbonate (i.e., the magnesium carbonate prepared in step 1) as a template in step 3, which further illustrates the feasibility of the template regeneration method provided by the embodiment of the present invention.
Example 3
This example provides a method for preparing graphene by fluidized bed chemical vapor deposition, which is different from example 1 only in that:
the carbon source gas is acetylene, and the roasting temperature and the reaction temperature are both 800 ℃.
In this example, the porous magnesium oxide obtained by calcining the rod-like magnesium carbonate at 800 ℃ for 20min also had a three-dimensional porous structure.
In this embodiment, the graphene prepared by using the bar-shaped magnesium carbonate as the template agent perfectly maintains the three-dimensional bar-shaped morphology of the magnesium carbonate template agent.
In this embodiment, the magnesium carbonate obtained after the regeneration in step 4 has the same micro-morphology as the initial magnesium carbonate prepared in step 1, that is, the morphology of the magnesium carbonate obtained after the regeneration in step 4 is also an obvious rod shape, which actually illustrates the feasibility of the template regeneration method provided in the embodiment of the present invention.
In this embodiment, the graphene prepared by using acetylene as a carbon source gas and using the rod-shaped magnesium carbonate obtained after regeneration as a template in step 5 has the same microscopic morphology as the graphene prepared by using ethylene as a carbon source gas and using the initial rod-shaped magnesium carbonate (i.e., the magnesium carbonate prepared in step 1) as a template in step 3, which further illustrates the feasibility of the template regeneration method provided by the embodiment of the present invention.
Example 4
This example provides a method for preparing graphene by fluidized bed chemical vapor deposition, which is different from example 1 only in that:
the carbon source gas is methane, and the roasting temperature and the reaction temperature are both 800 ℃.
In this example, the porous magnesium oxide obtained by calcining rod-like magnesium carbonate at 800 ℃ for 20min also had a three-dimensional porous structure.
In this embodiment, the graphene prepared by using the bar-shaped magnesium carbonate as the template agent perfectly maintains the three-dimensional bar-shaped morphology of the magnesium carbonate template agent.
In this embodiment, the magnesium carbonate obtained after the regeneration in step 4 has the same micro morphology as the initial magnesium carbonate prepared in step 1, that is, the morphology of the magnesium carbonate obtained after the regeneration in step 4 is also an obvious rod shape, which actually illustrates the feasibility of the template regeneration method provided in the embodiment of the present invention.
In this embodiment, the graphene prepared by using methane as the carbon source gas and the rod-shaped magnesium carbonate obtained after regeneration as the template in step 5 has the same micro morphology as the graphene prepared by using methane as the carbon source gas and the initial rod-shaped magnesium carbonate (i.e., the magnesium carbonate prepared in step 1) as the template in step 3, which further illustrates the feasibility of the template regeneration method provided by the embodiment of the present invention.
Example 5
This example provides a method for preparing graphene by fluidized bed chemical vapor deposition, which is different from example 1 only in that:
the template agent is flower-shaped hollow tube magnesium carbonate, and the water bath temperature in the preparation process of the flower-shaped hollow tube magnesium carbonate is 50 ℃; the width of the flower-shaped hollow magnesium carbonate tube is 0.5-1 μm, the length range is 5-30 μm, the length-diameter ratio is 10-30, and the data of the width, the length and the length-diameter ratio of the flower-shaped hollow magnesium carbonate tube can be obtained by the following figure 7;
the roasting temperature and the reaction temperature in the fluidized bed chemical vapor deposition process are both 800 ℃.
The scanning electron microscope image of the magnesium carbonate template agent with the flower-shaped hollow tube prepared in the embodiment 5 is shown in fig. 7, and it can be seen from fig. 7 that the magnesium carbonate prepared in the embodiment is actually composed of a flower-shaped lamellar structure, that is, the appearance of the magnesium carbonate is the flower-shaped hollow tube.
In this example, the porous magnesium oxide obtained by calcining magnesium carbonate in a flower-shaped hollow tube at 800 ℃ for 20min also has a three-dimensional porous structure.
In the embodiment, the graphene prepared by taking the flower-shaped hollow tube magnesium carbonate as the template agent perfectly maintains the appearance of the flower-shaped hollow tube of the magnesium carbonate template agent, and therefore, in the embodiment, the graphene is prepared by a fluidized bed chemical vapor deposition method, and the prepared graphene can well maintain the appearance of the template agent.
The scanning electron microscope image of the magnesium carbonate template agent with flower-shaped hollow tubes obtained after regeneration in this example 5 is shown in fig. 8, and comparing fig. 7 and fig. 8, it can be seen that the magnesium carbonate obtained after regeneration has the same microscopic morphology as the original magnesium carbonate, that is, the magnesium carbonate obtained after regeneration also consists of a flower-shaped lamellar structure (i.e., the morphology of the magnesium carbonate is flower-shaped hollow tubes), which actually illustrates the feasibility of the template regeneration method provided by the embodiment of the present invention.
In this embodiment, the graphene prepared by using methane as the carbon source gas in step 5 and using the flower-shaped hollow tube magnesium carbonate obtained after regeneration as the template has the same microscopic morphology as the graphene prepared by using methane as the carbon source gas in step 3 and using the original flower-shaped hollow tube magnesium carbonate (i.e., the magnesium carbonate prepared in step 1) as the template, which further illustrates the feasibility of the template regeneration method provided by the embodiment of the present invention.
Example 6
This example provides a method for preparing graphene by fluidized bed chemical vapor deposition, which is different from example 1 only in that:
the template agent is rose-shaped magnesium carbonate, and the water bath temperature in the preparation process of the rose-shaped magnesium carbonate is 50 ℃ and the time is 2 hours; as shown in the following fig. 9, the diameter of the rose-like magnesium carbonate was 2 μm;
the roasting temperature and the reaction temperature in the fluidized bed chemical vapor deposition process are both 800 ℃.
The scanning electron micrograph of the magnesium carbonate in the rose shape prepared in this example 6 is shown in fig. 9, and it can be seen from fig. 9 that the magnesium carbonate prepared in this example is composed of a flower-like lamellar structure and appears in a cluster shape, that is, the morphology is in the rose shape.
In this example, the porous magnesium oxide obtained by calcining rose-shaped magnesium carbonate at 800 ℃ for 20min also has a three-dimensional porous structure.
In the embodiment, the graphene prepared by taking rose-shaped magnesium carbonate as the template agent perfectly maintains the rose-shaped morphology of the magnesium carbonate template agent, and as can be seen, the graphene prepared by the fluidized bed chemical vapor deposition method in the embodiment can well maintain the morphology of the template agent.
In this embodiment, the magnesium carbonate obtained after regeneration has the same microscopic morphology as the original magnesium carbonate, that is, the magnesium carbonate obtained after regeneration also consists of a flower-like lamellar structure and is in a cluster shape (that is, the shape of the magnesium carbonate is in a rose shape), which actually demonstrates the feasibility of the template regeneration method provided by the embodiment of the present invention.
In this embodiment, the graphene prepared by using methane as a carbon source gas and rose-shaped magnesium carbonate obtained after regeneration as a template in step 5 has the same microscopic morphology as the graphene prepared by using methane as a carbon source gas and the original rose-shaped magnesium carbonate (i.e., the magnesium carbonate prepared in step 1) as a template in step 3, which further illustrates the feasibility of the template regeneration method provided by the embodiment of the present invention.
Application example 1
The application example provides a supercapacitor, wherein electrode materials of the supercapacitor are respectively graphene prepared in step 3 and step 5 of embodiment 1, and are respectively marked as initial graphene and regenerated graphene;
the CV curves of the initial graphene and the regenerated graphene obtained in example 1 when applied to the electrode material of the supercapacitor are respectively shown in fig. 10 and fig. 11, and as can be seen from fig. 10 and fig. 11, the CV curves both present an approximately rectangular shape, which indicates that the initial graphene and the regenerated graphene prepared in example 1 both have good electrochemical properties, and as can be seen from fig. 10 and 11, the electrochemical properties of the initial graphene and the regenerated graphene prepared in example 1 are close to each other.
Application example 2
The application example provides a supercapacitor, wherein electrode materials of the supercapacitor are respectively graphene prepared in step 3 and step 5 of embodiment 5, and are respectively marked as initial graphene and regenerated graphene;
when the initial graphene and the regenerated graphene obtained in example 5 are applied to the electrode material of the supercapacitor, CV curves are shown in fig. 12, and GCD curves are shown in fig. 13, and it can be seen from fig. 12 and 13 that the electrochemical performances of the initial graphene and the regenerated graphene prepared in example 5 are close to each other.
In summary, the method for preparing graphene by fluidized bed chemical vapor deposition provided in the embodiments of the present invention is easy to control, has low operation cost and simple process, can not only realize recycling of the template agent, but also realize batch preparation of graphene by fluidized bed chemical vapor deposition, and further can greatly reduce production cost of graphene.
It should be understood that the above description is only exemplary of the invention, and is not intended to limit the scope of the invention, so that the replacement of equivalent elements or equivalent changes and modifications made in the present invention should be included within the scope of the present invention. In addition, the technical features and the technical inventions of the present invention, the technical features and the technical inventions, and the technical inventions can be freely combined and used.
Claims (22)
1. A preparation method of graphene comprises the following steps:
(1) Preparing a compound of graphene and a template agent by using magnesium carbonate as the template agent and adopting a fluidized bed chemical vapor deposition method; wherein the magnesium carbonate is one or a combination of several of rod-shaped magnesium carbonate, flower-shaped hollow tube magnesium carbonate or rose-shaped magnesium carbonate;
(2) Removing the template agent in the compound of the graphene and the template agent in an acid washing mode to obtain the graphene;
(3) And (2) adding a carbonate aqueous solution into the filtrate after the acid washing, obtaining magnesium carbonate through regeneration, and circulating the magnesium carbonate obtained after the regeneration to the step (1) to be used as a template agent so as to continuously prepare the graphene.
2. The method according to claim 1, wherein step (3) comprises the specific steps of:
and (2) adding a carbonate aqueous solution into the filtrate after acid washing according to the molar ratio of 1.
3. A process according to claim 1 or 2, characterized in that the magnesium carbonate is prepared by:
adding a sodium carbonate aqueous solution into a magnesium chloride aqueous solution, stirring and reacting for 0.5-6h in a water bath at the temperature of 20-80 ℃, and drying a solid product obtained by the reaction to obtain the magnesium carbonate.
4. The method according to claim 3, wherein the concentration of the aqueous sodium carbonate solution and the concentration of the aqueous magnesium chloride solution are both 0.1-1mol/L.
5. The method according to claim 4, wherein the concentration of the aqueous sodium carbonate solution and the concentration of the aqueous magnesium chloride solution are both 0.5mol/L.
6. The process according to claim 3, characterized in that the reaction time is 1h.
7. The method of claim 3, wherein the drying is drying at 100 ℃ for 2-24h.
8. The method of claim 1, wherein the fluidized bed chemical vapor deposition process comprises the steps of:
and introducing carrier gas into the fluidized bed reactor, simultaneously heating the fluidized bed reactor to the reaction temperature, adding a magnesium carbonate template into the fluidized bed reactor, roasting for a period of time, introducing a carbon source gas into the fluidized bed reactor, performing deposition reaction on the roasted magnesium carbonate template with the carbon source gas, and obtaining the compound of graphene and the template after the reaction is finished.
9. The method as claimed in claim 8, wherein the roasting temperature is 600-900 ℃ and the roasting time is 10-60min.
10. The method of claim 9, wherein the firing temperature is 700 ℃.
11. The method of claim 8, wherein the reaction temperature is 600-1000 ℃, the reaction pressure is 0.1-0.15MPa, and the reaction time is 5-100min.
12. The method according to claim 11, wherein the reaction temperature is 600-900 ℃ and the reaction time is 10-30min.
13. The method according to claim 8, wherein the carrier gas and the carbon source gas have a gas velocity of 0.001 to 1m/s, respectively.
14. The method as claimed in claim 13, wherein the carrier gas and the carbon source gas have a gas velocity of 0.005-0.1m/s, respectively.
15. The method of claim 1 or 2, wherein the carbon source gas for the fluidized bed chemical vapor deposition method comprises one or more of methane, ethane, ethylene, acetylene and propane.
16. The method of claim 15, wherein the carbon source gas is methane, ethylene, or acetylene.
17. The method of claim 1 or 2, wherein the carrier gas for the fluidized bed chemical vapor deposition comprises one or more of nitrogen, argon and helium.
18. The method according to any one of claims 8 to 14, wherein the molar ratio of the carrier gas to the carbon source gas is from 0.1 to 10.
19. The method of claim 18, wherein the molar ratio of the carrier gas to the carbon source gas is 0.5-2.
20. Graphene obtained by the method for producing graphene according to any one of claims 1 to 19;
wherein the specific surface area of the graphene is 1500-2000m 2 The pore size distribution range is 2-10nm.
21. Use of the graphene of claim 20 as an electrode material for a supercapacitor.
22. A supercapacitor, wherein an electrode material of the supercapacitor is the graphene according to claim 20.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110545312.0A CN113148994B (en) | 2021-05-19 | 2021-05-19 | Graphene and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110545312.0A CN113148994B (en) | 2021-05-19 | 2021-05-19 | Graphene and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113148994A CN113148994A (en) | 2021-07-23 |
| CN113148994B true CN113148994B (en) | 2022-12-20 |
Family
ID=76876497
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110545312.0A Active CN113148994B (en) | 2021-05-19 | 2021-05-19 | Graphene and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113148994B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113697807B (en) * | 2021-07-23 | 2023-06-09 | 中国石油大学(北京) | Method for preparing capacitance carbon by using chloride salt as template agent and circularly regenerating template agent |
| CN116477610B (en) * | 2023-06-09 | 2023-09-12 | 西南石油大学 | Graphene nano-sheet prepared from magnesium-containing wastewater and preparation method and application thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102127750A (en) * | 2011-03-01 | 2011-07-20 | 哈尔滨工程大学 | Method for preparing graphene material based on chemical deposition |
| CN102491315A (en) * | 2011-12-08 | 2012-06-13 | 中国科学院化学研究所 | Method for preparing graphene |
| CN103395767A (en) * | 2013-07-25 | 2013-11-20 | 中国石油大学(北京) | Preparation method of sulfur-containing carbon material as well as sulfur-containing carbon material prepared by using same |
| CN106587017A (en) * | 2016-12-14 | 2017-04-26 | 中国石油大学(北京) | Porous graphene and preparation method thereof |
| CN108002371A (en) * | 2017-12-20 | 2018-05-08 | 中石油燃料油有限责任公司研究院 | porous graphene and preparation method thereof |
| CN109264706A (en) * | 2018-10-16 | 2019-01-25 | 李红莉 | A kind of method of the three-D nano-porous graphene powder of chemical vapour deposition technique controllable preparation |
| CN109524647A (en) * | 2018-11-07 | 2019-03-26 | 新奥石墨烯技术有限公司 | A kind of mesoporous grapheme material of micron order |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101790275B1 (en) * | 2013-10-24 | 2017-10-26 | 한국과학기술원 | high quality graphene quantum dots and method for preparing the same |
| CN104726845B (en) * | 2015-03-05 | 2018-05-01 | 中国科学院上海微***与信息技术研究所 | The preparation method of the upper graphene nanobelts of h-BN |
-
2021
- 2021-05-19 CN CN202110545312.0A patent/CN113148994B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102127750A (en) * | 2011-03-01 | 2011-07-20 | 哈尔滨工程大学 | Method for preparing graphene material based on chemical deposition |
| CN102491315A (en) * | 2011-12-08 | 2012-06-13 | 中国科学院化学研究所 | Method for preparing graphene |
| CN103395767A (en) * | 2013-07-25 | 2013-11-20 | 中国石油大学(北京) | Preparation method of sulfur-containing carbon material as well as sulfur-containing carbon material prepared by using same |
| CN106587017A (en) * | 2016-12-14 | 2017-04-26 | 中国石油大学(北京) | Porous graphene and preparation method thereof |
| CN108002371A (en) * | 2017-12-20 | 2018-05-08 | 中石油燃料油有限责任公司研究院 | porous graphene and preparation method thereof |
| CN109264706A (en) * | 2018-10-16 | 2019-01-25 | 李红莉 | A kind of method of the three-D nano-porous graphene powder of chemical vapour deposition technique controllable preparation |
| CN109524647A (en) * | 2018-11-07 | 2019-03-26 | 新奥石墨烯技术有限公司 | A kind of mesoporous grapheme material of micron order |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113148994A (en) | 2021-07-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113148994B (en) | Graphene and preparation method and application thereof | |
| WO2019109831A1 (en) | Method for preparing copper-nickel cobaltate nanowires and use thereof in catalyzing hydrolysis of ammonia borane to produce hydrogen | |
| CN106185896B (en) | The preparation method of three-dimensional grapheme and its composite material | |
| WO2016101436A1 (en) | Method for preparing structure-controllable 3d graphene porous material | |
| KR20090015449A (en) | Method for the preparation of porous graphite carbon with high crystallinity using sucrose as a carbon precursor | |
| CN105905908B (en) | A kind of method that nano-silicon is prepared based on galapectite raw material | |
| CN108557799B (en) | High-purity high-conductivity graphene-like hierarchical porous carbon and preparation method thereof | |
| CN109626364A (en) | A kind of preparation method of nitrogen sulphur codope three-dimensional grapheme | |
| CN103112844B (en) | Macro preparation method for mesoporous ordered graphene | |
| CN108285139B (en) | Preparation method and application of nitrogen-doped graphene carbon material | |
| US20230073650A1 (en) | Carbon nanotube (cnt)-based three-dimensional ordered macroporous (3dom) material and preparation method thereof | |
| AU2020102823A4 (en) | Method for preparing carbon nanotube-porous carbon composite materials | |
| CN107161989A (en) | A kind of preparation method of cellular three-dimensional grapheme | |
| CN111924828B (en) | Array type carbon nano tube and preparation method thereof | |
| CN106082175B (en) | A method of melting sodium carbonate high temperature prepares carbide-derived carbon | |
| CN106744859A (en) | Graphene three-dimensional multistage pore structure powder prepared by a kind of low temperature polymer cracking | |
| CN111162266B (en) | Carbon-coated two-dimensional silicon and preparation method and application thereof | |
| CN114284487A (en) | Porous metal oxide, preparation method thereof and application thereof in sodium-ion battery | |
| CN110921651A (en) | Preparation of three-dimensional carbon-based composite material by metal-assisted salt template method | |
| CN107572509B (en) | Nitrogen-doped hollow carbon/graphite nodule nano material and preparation method thereof | |
| CN116159568B (en) | Self-contained nano-sheet nickel-based ammonia decomposition catalyst and preparation method and application thereof | |
| CN111943722A (en) | Controllable method for synthesizing carbon nano tube on surface of foamed ceramic and application thereof | |
| CN111732102B (en) | Method for preparing porous carbon material by ruthenium particle assisted etching in strong alkaline environment | |
| CN111533112A (en) | Graphene hollow nanospheres and preparation method thereof | |
| CN109824060B (en) | Ammonia-rich concave Prussian blue material and preparation method 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 |