Intrinsic defect graphene and method of making the same

Abstract

The application relates to the technical field of nanometer carbon material preparation, in particular to intrinsic defect graphene and a preparation method thereof. High-purity graphite powder is mixed with benzoyl peroxide, and then grinded to obtain gray powder; the gray powder is constant-temperature calcined under air atmosphere, and then naturally cooled to room temperature to obtain black expanded powder; the black expanded powder is constant-temperature calcined under ammonia atmosphere, and then naturally cooled to room temperature to obtain nitrogen-doped graphite; the nitrogen-doped graphite is pressed into a rod to serve as an anode of an electric arc furnace, high-purity graphite rods serve as cathodes of the electric arc furnace, arc discharge is carried out under hydrogen and protective gas atmosphere, the generated soot in the furnace cavity is collected when the anode rod is consumed, and intrinsic defect graphene is obtained. The application does not need to take graphene or heteroatom-doped graphene as a premise, can directly use high-purity graphene as a precursor, and solves the problems of high cost and low efficiency existing in the existing intrinsic defect graphene preparation method.

Description

Technical Field

[0001] This invention relates to the field of nanomaterial preparation technology, specifically to an intrinsically defective graphene and its preparation method. Background Technology

[0002] Studies have shown that the structure of graphene is composed of sp 2 Composed of carbon atoms, graphene exhibits good electrical conductivity and high stability but lacks catalytic / energy storage activity. Intrinsic defects can help modulate the band structure of graphene, increase reactive sites, and improve its surface electron transport processes, thereby endowing it with high electrochemical activity. Therefore, introducing intrinsic defects into the structure of graphene, i.e., preparing intrinsically defective graphene, has attracted widespread attention from scientists in the fields of catalysis and energy storage.

[0003] The existing methods for preparing intrinsically defective graphene mainly include the following: 1) using plasma equipment to etch milligram-scale graphene (Appl. Catal. A-Gen., 2017, 529: 127-133); 2) treating heteroatom-doped graphene under high temperature (≥1100℃) and inert atmosphere conditions (Jia et al, Adv. Mater., 2016, 28, 9532); 3) using CVD method, with calcium oxide as template and catalyst, to prepare a small amount of intrinsically defective graphene with a layered structure under high temperature conditions (Tang et al, Adv. Funct. Mater., 2016, 26(4): 577-585); 4) using scanning electron microscopy to photolithographically etch micro-scale graphene nanosheets (O'Hem et al, Nano Letters, 2014, 14(3): 1234-1241).

[0004] In summary, it can be seen that existing technologies for preparing intrinsically defective graphene all require graphene or heteroatoms as precursors, and some methods even require plasma equipment or scanning electron microscopes, resulting in high costs. Furthermore, existing technologies have low yields per batch, only reaching the milligram level, which is inefficient and cannot meet the needs of large-scale practical production and applications. Therefore, finding a low-cost and high-efficiency method for preparing intrinsically defective graphene remains a crucial problem that urgently needs to be solved. Summary of the Invention

[0005] To address the shortcomings of the existing technologies, the purpose of this invention is to provide an intrinsically defective graphene and its preparation method. This invention does not require graphene or heteroatom-doped graphene as a prerequisite, and can directly use high-purity graphene as a precursor, thus solving the problems of high cost and low efficiency in existing intrinsically defective graphene preparation methods.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A method for preparing intrinsically defective graphene includes the following steps:

[0008] High-purity graphite powder is mixed with benzoyl peroxide and ground to obtain a gray powder. The gray powder is then calcined at a constant temperature in air. After the benzoyl peroxide is mixed evenly with the graphite powder, calcination in air can transform the graphite powder into expanded graphite, increasing the interlayer spacing and providing a better doping path for nitrogen atom doping in subsequent processes. This makes it easier for nitrogen atoms to be doped into the interlayer or surface of the graphite. After natural cooling to room temperature, a black expanded powder is obtained.

[0009] The black expanded powder was calcined at a constant temperature under an ammonia atmosphere to dope nitrogen atoms into the interlayer or surface of graphite. After natural cooling to room temperature, nitrogen-doped graphite was obtained.

[0010] The nitrogen-doped graphite is pressed into rods and used as the anode of an electric arc furnace. High-purity graphite rods are used as the cathode of the electric arc furnace. Under the conditions of hydrogen and protective gas atmosphere, electric arc discharge is performed. During the electric arc discharge, the graphite is stripped away, and the high temperature during the electric arc discharge removes nitrogen atoms between graphite layers, forming vacancies, thereby creating intrinsic defects. After the anode rod is consumed, the soot generated in the furnace cavity is collected to obtain intrinsically defective graphene.

[0011] This invention eliminates the need for graphene or heteroatom-doped graphene as a precursor, allowing the direct use of high-purity graphite powder. It is the first to employ an electric arc furnace to prepare intrinsically defective graphene. Nitrogen-doped graphite is pressed into rods and used as electrodes. Through a one-step rapid arc discharge, nitrogen atoms are selectively removed from the graphene structure simultaneously, creating vacancies and converting it into intrinsically defective graphene. This method is fast, efficient, and yields high production volumes, reaching gram-level outputs. It solves the problems of high cost and low efficiency in existing intrinsic graphene preparation methods.

[0012] In a preferred embodiment of the present invention, the arc discharge voltage is 12V to 20V and the current is 110A to 130A.

[0013] In a preferred embodiment of the present invention, the mass ratio of high-purity graphite powder to benzoyl peroxide is 1 to 3:1.

[0014] In a preferred embodiment of the present invention, the gray powder is calcined at a constant temperature of 120°C to 150°C in an air atmosphere for 20 to 30 minutes.

[0015] In a preferred embodiment of the present invention, the black expanded powder is calcined at a constant temperature of 800℃~900℃ under an ammonia atmosphere for 1h~3h.

[0016] In a preferred embodiment of the present invention, the diameter of the high-purity stone grinding rod is 8mm to 12mm.

[0017] In a preferred embodiment of the present invention, the protective gas is one or a mixture of nitrogen, argon and helium.

[0018] In a preferred embodiment of the present invention, the grinding time is 30 min to 40 min.

[0019] In a preferred embodiment of the present invention, the purity of the graphite powder is ≥99.9%.

[0020] Another object of the present invention is to provide intrinsically defective graphene prepared by any of the above-described preparation methods.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] 1. This invention involves mixing high-purity graphite powder with benzoyl peroxide to obtain a gray powder. The gray powder is then calcined at a constant temperature in an air atmosphere. After the benzoyl peroxide and graphite are uniformly mixed, calcination in air transforms the graphite powder into expanded graphite, increasing the interlayer spacing and providing a better doping path for nitrogen atom doping in subsequent processes. This makes it easier for nitrogen atoms to be doped into the graphite interlayers or surface, resulting in a black expanded powder. The black expanded powder is then calcined at a constant temperature in an ammonia atmosphere, allowing nitrogen atoms to be doped into the graphite interlayers or surface, resulting in nitrogen-doped graphite. The nitrogen-doped graphite is pressed into rods and used as the anode of an electric arc furnace. A high-purity graphite rod is used as the cathode of the electric arc furnace. An electric arc discharge is performed under a hydrogen and protective gas atmosphere. The high temperature during the arc discharge removes nitrogen atoms from the graphite interlayers, creating vacancies and thus generating intrinsic defects. After the anode rod is consumed, the soot generated in the furnace cavity is collected to obtain intrinsically defective graphene. This invention eliminates the need for graphene or heteroatom-doped graphene as a precursor, allowing the direct use of high-purity graphite powder. It is the first to employ an electric arc furnace to prepare intrinsically defective graphene. Nitrogen-doped graphite is pressed into rods and used as electrodes. Through a one-step rapid arc discharge, nitrogen atoms are selectively removed from the graphene structure simultaneously, creating vacancies and converting it into intrinsically defective graphene. This method is fast, efficient, and yields high production volumes, reaching gram-level outputs. It solves the problems of high cost and low efficiency in existing intrinsic graphene preparation methods.

[0023] 2. The raw materials such as benzoyl peroxide involved in the preparation process of this invention are inexpensive and readily available, resulting in low cost. Furthermore, by adjusting the calcination time under an ammonia atmosphere and thus the nitrogen content of the nitrogen-doped graphene, the beneficial effect of controlling the defect content in intrinsically defective graphene can also be achieved. Attached Figure Description

[0024] Figure 1 Transmission electron microscope image of intrinsically defective graphene prepared in Example 1 of the present invention.

[0025] Figure 2 Transmission electron microscope image of intrinsically defective graphene prepared in Example 2 of the present invention.

[0026] Figure 3 Transmission electron microscope image of intrinsically defective graphene prepared in Example 3 of the present invention.

[0027] Figure 4 Transmission electron microscope image of intrinsically defective graphene prepared in Example 4 of the present invention.

[0028] Figure 5 Transmission electron microscope image of intrinsically defective graphene prepared in Example 5 of the present invention.

[0029] Figure 6 In the diagram, A is the high-resolution N11 spectrum of nitrogen-doped graphene obtained by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 1, and B is the high-resolution N11 spectrum of intrinsically defective graphene.

[0030] Figure 7 In the diagram, A is the high-resolution N11 spectrum of nitrogen-doped graphene obtained by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 2, and B is the high-resolution N11 spectrum of intrinsically defective graphene.

[0031] Figure 8 In the diagram, A is the high-resolution N11 spectrum of nitrogen-doped graphene obtained by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 3, and B is the high-resolution N11 spectrum of intrinsically defective graphene.

[0032] Figure 9 In the diagram, A is the high-resolution N11 spectrum of nitrogen-doped graphene obtained by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 4, and B is the high-resolution N11 spectrum of intrinsically defective graphene.

[0033] Figure 10 In the diagram, A is the high-resolution N11 spectrum of nitrogen-doped graphene obtained by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 5, and B is the high-resolution N11 spectrum of intrinsically defective graphene. Detailed Implementation

[0034] The following detailed description, in conjunction with embodiments of the present invention and accompanying drawings, provides a clear and complete illustration of the technical solutions in these embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0035] It should be noted that all technical terms used in this invention are for the purpose of describing specific embodiments only and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of this invention can be purchased from the market or prepared by existing methods.

[0036] Example 1

[0037] A method for preparing intrinsically defective graphene includes the following steps:

[0038] (1) Mix high-purity graphite powder with a purity of 99.9% with benzoyl peroxide at a mass ratio of 3:1 and grind for 30 min to obtain a gray powder.

[0039] (2) The gray powder was placed in a crucible and calcined at 120°C in air for 20 minutes. It was then naturally cooled to room temperature to obtain black expanded graphite.

[0040] (3) The black expanded graphite was calcined at 800°C in an ammonia atmosphere for 2 hours and then naturally cooled to room temperature to obtain nitrogen-doped graphite.

[0041] (4) The nitrogen-doped graphite is pressed into a rod with a diameter of 6 mm and used as the anode of the electric arc furnace. A high-purity graphite rod is used as the cathode. Under the mixed atmosphere of hydrogen and protective gas, an electric arc discharge is performed. The volume ratio of hydrogen to protective gas is 1:3. The electric arc discharge voltage is 15V and the current is 120A. The discharge continues until the anode rod is consumed. After the furnace body is cooled to room temperature, the soot generated in the furnace cavity is collected. The soot is the intrinsic defect graphene.

[0042] Figure 1 The transmission electron microscope image of the intrinsic defect graphene prepared in Example 1 shows that the intrinsic graphene is sheet-like with curled edges, and the sheet size is between 200 nm and 500 nm.

[0043] Figure 6 In the diagram, A is the high-resolution N1s spectrum of nitrogen-doped graphene prepared in Example 1 using X-ray photoelectron spectroscopy, and B is the high-resolution N1s spectrum of intrinsically defective graphene. The N1s spectra before and after the arc discharge in the XPS spectra show that the nitrogen content decreased from 5.47 at.% to 0.16 at.% before and after the introduction of intrinsic defects. This indicates that the method of the present invention can remove nitrogen atoms between graphite layers using the high temperature (4000K~6000K) of the arc discharge while simultaneously exfoliating the graphite, thereby creating intrinsic defects. These results demonstrate that the present invention can successfully prepare graphene with intrinsic defects.

[0044] Example 2

[0045] A method for preparing intrinsically defective graphene includes the following steps:

[0046] (1) Mix high-purity graphite powder with a purity of 99.9% with benzoyl peroxide at a mass ratio of 3:1 and grind for 40 min to obtain a gray powder.

[0047] (2) The gray powder was placed in a crucible and calcined at 130°C in air for 20 minutes. It was then naturally cooled to room temperature to obtain black expanded graphite.

[0048] (3) The black expanded graphite was calcined at 850°C in an ammonia atmosphere for 2 hours and then naturally cooled to room temperature to obtain nitrogen-doped graphite.

[0049] (4) The nitrogen-doped graphite is pressed into a rod with a diameter of 7 mm and used as the anode of the electric arc furnace. A high-purity graphite rod is used as the cathode. Under the mixed atmosphere of hydrogen and protective gas, an electric arc discharge is performed. The volume ratio of hydrogen to protective gas is 1:3. The electric arc discharge voltage is 15V and the current is 120A. The discharge continues until the anode rod is consumed. After the furnace body is cooled to room temperature, the soot generated in the furnace cavity is collected. The soot is the intrinsic defect graphene.

[0050] Figure 2 The image shown is a transmission electron microscope (TEM) image of the intrinsically defective graphene prepared in Example 2. It can be seen that the intrinsically defective graphene prepared in Example 2 exhibits a sheet-like structure with curled edges, and an average size between 200 nm and 500 nm. Figure 7 In the figure, A is the high-resolution N1s spectrum of nitrogen-doped graphene prepared by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 2, and B is the high-resolution N1s spectrum of intrinsically defective graphene. It can be seen from the N1s spectra before and after the arc in the XPS spectrum that the nitrogen content decreased from 6.05 at.% to 0.19 at.% before and after the introduction of intrinsic defects.

[0051] Example 3

[0052] A method for preparing intrinsically defective graphene includes the following steps:

[0053] (1) Mix high-purity graphite powder with a purity of 99.9% with benzoyl peroxide at a mass ratio of 3:1 and grind for 40 min to obtain a gray powder.

[0054] (2) The gray powder was placed in a crucible and calcined at 150°C in air for 20 minutes. It was then naturally cooled to room temperature to obtain black expanded graphite.

[0055] (3) The black expanded graphite was calcined at 900°C in an ammonia atmosphere for 1 hour and then naturally cooled to room temperature to obtain nitrogen-doped graphite.

[0056] (4) The nitrogen-doped graphite is pressed into a rod with a diameter of 8 mm and used as the anode of the electric arc furnace. A high-purity graphite rod is used as the cathode. Under the mixed atmosphere of hydrogen and protective gas, an electric arc discharge is performed. The volume ratio of hydrogen to protective gas is 1:3, the electric arc discharge voltage is 15V, and the current is 120A. The discharge continues until the anode rod is consumed. After the furnace body is cooled to room temperature, the soot generated in the furnace cavity is collected. The soot is the intrinsic defect graphene.

[0057] Figure 3 The image shown is a transmission electron microscope (TEM) image of the intrinsically defective graphene prepared in Example 3. It can be seen that the intrinsically defective graphene prepared in Example 3 exhibits a sheet-like structure with curled edges, and an average size between 200 nm and 500 nm. Figure 8 In the figure, A is the high-resolution N1s spectrum of nitrogen-doped graphene prepared by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 3, and B is the high-resolution N1s spectrum of intrinsically defective graphene. It can be seen from the N1s spectrum before and after the arc in the XPS spectrum that the nitrogen content decreased from 6.02 at.% to 0.14 at.% before and after the introduction of intrinsic defects.

[0058] Example 4

[0059] A method for preparing intrinsically defective graphene includes the following steps:

[0060] (1) Mix high-purity graphite powder with a purity of 99.9% with benzoyl peroxide at a mass ratio of 3:1 and grind for 30 min to obtain a gray powder.

[0061] (2) The gray powder was placed in a crucible and calcined at 150°C in air for 30 minutes. It was then naturally cooled to room temperature to obtain black expanded graphite.

[0062] (3) The black expanded graphite was calcined at 900°C in an ammonia atmosphere for 2 hours and then naturally cooled to room temperature to obtain nitrogen-doped graphite.

[0063] (4) The nitrogen-doped graphite is pressed into a rod with a diameter of 8 mm and used as the anode of the electric arc furnace. A high-purity graphite rod is used as the cathode. Under the mixed atmosphere of hydrogen and protective gas, an electric arc discharge is performed. The volume ratio of hydrogen to protective gas is 1:3, the electric arc discharge voltage is 15V, and the current is 120A. The discharge continues until the anode rod is consumed. After the furnace body is cooled to room temperature, the soot generated in the furnace cavity is collected. The soot is the intrinsic defect graphene.

[0064] Figure 4 The image shown is a transmission electron microscope (TEM) image of the intrinsically defective graphene prepared in Example 4. It can be seen that the intrinsically defective graphene prepared in Example 4 exhibits a sheet-like structure with curled edges, and an average size between 200 nm and 500 nm. Figure 9 In the figure, A is the high-resolution N1s spectrum of nitrogen-doped graphene prepared by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 4, and B is the high-resolution N1s spectrum of intrinsically defective graphene. It can be seen from the N1s spectra before and after the arc in the XPS spectrum that the nitrogen content decreased from 6.93 at.% to 0.22 at.% before and after the introduction of intrinsic defects.

[0065] Example 5

[0066] A method for preparing intrinsically defective graphene includes the following steps:

[0067] (1) Mix high-purity graphite powder with a purity of 99.9% with benzoyl peroxide at a mass ratio of 3:1 and grind for 40 min to obtain a gray powder.

[0068] (2) The gray powder was placed in a crucible and calcined at 150°C in air for 30 minutes. It was then naturally cooled to room temperature to obtain black expanded graphite.

[0069] (3) The black expanded graphite was calcined at 900°C in an ammonia atmosphere for 3 hours and then naturally cooled to room temperature to obtain nitrogen-doped graphite.

[0070] (4) The nitrogen-doped graphite is pressed into a rod with a diameter of 8 mm and used as the anode of the electric arc furnace. A high-purity graphite rod is used as the cathode. Under the mixed atmosphere of hydrogen and protective gas, an electric arc discharge is performed. The volume ratio of hydrogen to protective gas is 1:3, the electric arc discharge voltage is 15V, and the current is 120A. The discharge continues until the anode rod is consumed. After the furnace body is cooled to room temperature, the soot generated in the furnace cavity is collected. The soot is the intrinsic defect graphene.

[0071] Figure 5 The image shown is a transmission electron microscope (TEM) image of the intrinsically defective graphene prepared in Example 5. It can be seen that the intrinsically defective graphene prepared in Example 5 exhibits a sheet-like structure with curled edges, and an average size between 200 nm and 500 nm. Figure 10 In the figure, A is the high-resolution N1s spectrum of nitrogen-doped graphene prepared by X-ray photoelectron spectroscopy of intrinsically defective graphene prepared in Example 5, and B is the high-resolution N1s spectrum of intrinsically defective graphene. It can be seen from the N1s spectrum before and after the arc in the XPS spectrum that the nitrogen content decreased from 8.43 at.% to 0.27 at.% before and after the introduction of intrinsic defects.

[0072] Example 6

[0073] A method for preparing intrinsically defective graphene includes the following steps:

[0074] (1) Mix high-purity graphite powder with a purity of 99.9% with benzoyl peroxide at a mass ratio of 1:1 and grind for 35 min to obtain a gray powder.

[0075] (2) The gray powder was placed in a crucible and calcined at 120°C in air for 25 minutes. It was then naturally cooled to room temperature to obtain black expanded graphite.

[0076] (3) The black expanded graphite was calcined at 800°C in an ammonia atmosphere for 2 hours and then naturally cooled to room temperature to obtain nitrogen-doped graphite.

[0077] (4) The nitrogen-doped graphite is pressed into a rod with a diameter of 6 mm and used as the anode of the electric arc furnace. A high-purity graphite rod is used as the cathode. Under the mixed atmosphere of hydrogen and protective gas, an electric arc discharge is performed. The volume ratio of hydrogen to protective gas is 1:3. The electric arc discharge voltage is 12V and the current is 130A. The discharge continues until the anode rod is consumed. After the furnace body is cooled to room temperature, the soot generated in the furnace cavity is collected. The soot is the intrinsic defect graphene.

[0078] Example 7

[0079] A method for preparing intrinsically defective graphene includes the following steps:

[0080] (1) Mix high-purity graphite powder with a purity of 99.9% with benzoyl peroxide at a mass ratio of 2:1 and grind for 35 min to obtain a gray powder.

[0081] (2) The gray powder was placed in a crucible and calcined at 120°C in air for 20 minutes. It was then naturally cooled to room temperature to obtain black expanded graphite.

[0082] (3) The black expanded graphite was calcined at 800°C in an ammonia atmosphere for 2 hours and then naturally cooled to room temperature to obtain nitrogen-doped graphite.

[0083] (4) The nitrogen-doped graphite is pressed into a rod with a diameter of 6 mm and used as the anode of the electric arc furnace. A high-purity graphite rod is used as the cathode. Under the mixed atmosphere of hydrogen and protective gas, an electric arc discharge is performed. The volume ratio of hydrogen to protective gas is 1:3. The electric arc discharge voltage is 20V and the current is 110A. The discharge continues until the anode rod is consumed. After the furnace body is cooled to room temperature, the soot generated in the furnace cavity is collected. The soot is the intrinsic defect graphene.

[0084] In summary, this invention eliminates the need for graphene or heteroatom-doped graphene as a precursor, allowing the direct use of high-purity graphite powder. It is the first to employ an electric arc furnace to prepare intrinsically defective graphene. Nitrogen-doped graphite is pressed into rods and used as electrodes. Through a one-step rapid arc discharge, nitrogen atoms are selectively removed from the graphene structure simultaneously, creating vacancies and converting it into intrinsically defective graphene. This method is fast, efficient, and yields high production volumes, reaching gram-level outputs. It solves the problems of high cost and low efficiency in existing intrinsic graphene preparation methods.

[0085] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

[0086] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for producing intrinsic-defect graphene, characterized by, Includes the following steps: Graphite powder is mixed with benzoyl peroxide and ground to obtain a mixed powder. The mixed powder is then calcined at a constant temperature in air to transform the graphite powder into expanded graphite, increasing the interlayer spacing of the graphite. The mixture is then naturally cooled to room temperature to obtain expanded graphite. The expanded graphite was calcined at a constant temperature under an ammonia atmosphere to dope nitrogen atoms into the interlayer or surface of the graphite, and then naturally cooled to room temperature to obtain nitrogen-doped graphite. The nitrogen-doped graphite is pressed into a rod and used as the anode of an electric arc furnace. The graphite rod is used as the cathode of the electric arc furnace. Under the conditions of hydrogen and protective gas atmosphere, an electric arc discharge is performed, and nitrogen atoms between graphite layers are removed to form vacancies. After the anode rod is consumed, the soot generated in the furnace cavity is collected to obtain intrinsic defect graphene.

2. The method of producing intrinsic-defect graphene according to claim 1, wherein The arc discharge voltage is 12V~20V, and the current is 110A~130A.

3. The method of claim 1, wherein the intrinsic-defect graphene is prepared by the steps of: The mass ratio of graphite powder to benzoyl peroxide is 1 to 3:

1. ​ 4. The method of claim 1, wherein the intrinsic-defect graphene is prepared by the steps of: preparing a graphene oxide by a chemical vapor deposition method; and reducing the graphene oxide to prepare the intrinsic-defect graphene. The mixed powder was calcined in air at a constant temperature of 120℃~150℃ for 20min~30min.

5. The method of claim 1, wherein the intrinsic-defect graphene is prepared by the steps of: preparing a graphene oxide by a chemical vapor deposition method; and reducing the graphene oxide to prepare the intrinsic-defect graphene. Expanded graphite was calcined at a constant temperature of 800℃~900℃ under an ammonia atmosphere for 1h~3h.

6. The method of claim 1, wherein the intrinsic-defect graphene is prepared by the steps of: preparing a graphene oxide by a chemical vapor deposition method; and reducing the graphene oxide to prepare the intrinsic-defect graphene. The diameter of the graphite rod is 8mm to 12mm.

7. The method of claim 1, wherein the intrinsic-defect graphene is prepared by the steps of: preparing a graphene oxide by a chemical vapor deposition method; and reducing the graphene oxide to prepare the intrinsic-defect graphene. The protective gas is one or a mixture of nitrogen, argon and helium.

8. The method of claim 1, wherein the intrinsic-defect graphene is prepared by the steps of: preparing a graphene oxide by a chemical vapor deposition method; and reducing the graphene oxide to prepare the intrinsic-defect graphene. The grinding time is 30 to 40 minutes.

9. The method for preparing intrinsically defective graphene according to claim 1, characterized in that, The purity of the graphite powder is ≥99.9%.

10. Intrinsically defective graphene prepared by the preparation method according to any one of claims 1 to 9.

Images