Preparation methods of atomic-scale nanoporous graphene, the obtained graphene, and its applications.

Abstract

This invention relates to the field of graphene materials technology, and particularly to a method for preparing atomically porous graphene, the resulting graphene, and its applications. A method for preparing atomically porous graphene includes the following steps: S1: oxidizing a graphene substrate in an ozone atmosphere to obtain a graphene intermediate containing oxygen clusters; S2: irradiating the oxygen-cluster graphene intermediate with ultraviolet light at room temperature to form atomically porous graphene. The method for preparing atomically porous graphene provided in this application, by using selective photothermal vaporization to prepare nanopores, ensures that the pore size of the prepared graphene has atomic-level precision. This fundamentally breaks through the technical bottleneck of the mutual constraint between pore size and pore density in traditional methods.

Description

Technical Field

[0001] This invention relates to the field of graphene materials technology, and particularly to a method for preparing atomically nanoporous graphene, the obtained graphene, and its applications. Background Technology

[0002] Graphene, with its atomic-level thickness, excellent mechanical properties, and unique electronic / thermal characteristics, has significant application value in fields such as gas separation (e.g., hydrogen purification, carbon dioxide capture), seawater desalination, and thermal management. However, achieving precise control of angstrom-level nanopores remains a key bottleneck for its practical application.

[0003] Related technologies disclose methods for preparing nanopores, such as ion beams, electron beams, plasma etching, and sodium ion chemical etching. However, these methods have certain limitations, such as a wide pore size distribution (usually >1 nm), relatively poor selectivity, or expensive production equipment.

[0004] Therefore, developing a nanopore preparation technology that can achieve atomic-level precision, independently control pore size and pore density at room temperature, and has the potential for large-scale production has become a pressing technical challenge in this field. Summary of the Invention

[0005] In view of this, the present invention aims to at least partially solve one of the technical problems in the related art. To this end, the present invention provides a method for preparing atomically nanoporous graphene, the obtained graphene, and its applications. The method utilizes ozone to form strained oxygen clusters with a "core / shell" structure on the graphene lattice as a precursor; subsequently, the strained ether cores of the oxygen clusters are selectively vaporized at room temperature using ultraviolet light of a specific wavelength, thereby forming atomically nanopores.

[0006] To achieve the above-mentioned objectives, this application provides the following technical solution: The first aspect of this application provides a method for preparing atomically porous graphene, comprising the following steps: S1: The graphene substrate is placed in an ozone atmosphere for oxidation treatment to obtain a graphene intermediate with oxygen clusters. S2: The graphene intermediate containing oxygen clusters is irradiated with ultraviolet light at room temperature to form atomic-level nanoporous graphene. The atomically porous graphene has a pore size of 2 Å to 6 Å and a pore density of 0.1 × 10⁻⁶. 12 cm 2 ~10×10 12 cm 2 ; The concentration of ozone is 100ppm to 2000ppm; The oxidation treatment temperature described in S1 is 100℃~280℃.

[0007] In some alternative implementations, the ozone satisfies at least one of the following conditions: (1) The ozone comprises a mixture of O3 and O2, wherein the volume ratio of O2 to O3 is (8~15):1; (2) The flow rate of ozone is 10 sccm to 30 sccm.

[0008] In some optional embodiments, the oxidation treatment time is 2 min to 20 min.

[0009] In some optional implementations, the ultraviolet irradiation in S2 satisfies at least one of the following conditions: (1) The photon energy of ultraviolet light is 3.0 eV~3.5 eV; (2) Irradiation time is 5s~20s; (3) The power is 5W; (4) The optical power is 1000mW~10000mW.

[0010] In some alternative embodiments, the graphene substrate includes at least one of graphene, graphene oxide, reduced graphene oxide, element-doped graphene, and functionalized graphene.

[0011] In some alternative embodiments, the graphene substrate may be in the form of at least one of two-dimensional film, powder, three-dimensional film, or fiber.

[0012] In a second aspect, this application provides an atomically porous graphene prepared according to the method described above.

[0013] In some optional embodiments, the atomically porous graphene has a specific surface area of ​​520 m². 2 / g~660m 2 / g.

[0014] In some optional embodiments, the difference between the thermal diffusivity of the atomically porous graphene and that of the graphene substrate is 150 mm. 2 / s~250mm 2 / s.

[0015] A third aspect of this application provides an application of atomically porous graphene for use in supercapacitors, gas molecular sieves, thermally conductive components, and thermally insulating components.

[0016] The method for preparing atomic-level nanoporous graphene, the obtained graphene, and its applications provided in this application have the following beneficial effects: (1) The method for preparing atomically porous graphene provided in this application uses selective photothermal vaporization to prepare nanopores, ensuring that the pore size of the prepared graphene has atomic precision, with a pore size of 2 Å to 6 Å and a pore density of 0.1 × 10⁻⁶. 12 cm 2 ~10×10 12 cm 2 .

[0017] (2) The method for preparing atomic-level nanoporous graphene provided in this application achieves selective local photothermal vaporization at room temperature, which is highly selective and avoids thermal pore merging, thus ensuring the uniformity of pore size.

[0018] (3) The method for preparing atomic-level nanoporous graphene provided in this application is simple, efficient and low-cost, and provides the possibility for large-scale industrial production.

[0019] (4) The atomic-level nanoporous graphene substrate provided in this application is not limited in morphology and can cover two-dimensional film, powder, three-dimensional film or fiber. The material type can be selected from a wide range, including graphene, graphene oxide, reduced graphene oxide, element-doped graphene, functionalized graphene, etc., which provides guidance for the research on atomic-level pore control of materials of different morphologies.

[0020] (5) The graphene prepared by the atomic-level nanoporous graphene preparation method provided in this application has a large specific surface area and good thermal conductivity, and can be widely used in supercapacitors, gas molecular sieves, thermal conductive components, thermal insulation components and other fields.

[0021] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is the atomic-level nanoporous graphene product prepared in Example 1 of this application. Detailed Implementation

[0024] To make the technical solution and beneficial effects of this application more apparent and understandable, a detailed description is provided below by listing specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of this application. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional experimental conditions. Unless otherwise specified, all reagents and raw materials used in this application are commercially available.

[0025] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0026] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0027] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0028] [Preparation methods for atomically porous graphene] A method for preparing atomically porous graphene includes the following steps: S1: The graphene substrate is placed in an ozone atmosphere for oxidation treatment to obtain a graphene intermediate with oxygen clusters. S2: The graphene intermediate containing oxygen clusters is irradiated with ultraviolet light at room temperature to form atomic-level nanoporous graphene. The atomically porous graphene has a pore size of 2 Å to 6 Å and a pore density of 0.1 × 10⁻⁶. 12 cm 2 ~10×10 12 cm 2 ; The concentration of ozone is 100ppm to 2000ppm; The oxidation treatment temperature described in S1 is 100℃~280℃.

[0029] Further optionally, the pore size of the atomic-level nanoporous graphene can be any one or any two of 2Å, 3Å, 4Å, 5Å, 6Å, etc., without limitation.

[0030] It should be noted that the pore size of the atomic-level nanoporous graphene in this application is not necessarily a circular pore; the pore size refers to the maximum straight-line distance of the atomic-level nanopores.

[0031] It should be noted that the room temperature mentioned in this application refers to any temperature within the range of 20℃ to 40℃.

[0032] Further optionally, the concentration of ozone can be any one or any two of the following: 100ppm, 200ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm, 800ppm, 900ppm, 1000ppm, 1200ppm, 1500ppm, 1800ppm, 2000ppm, etc., without limitation herein.

[0033] Further optionally, the oxidation treatment temperature in S1 can be any one or any two of the following: 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 230℃, 240℃, 250℃, 260℃, 270℃, 280℃; for example, optionally, the oxidation treatment temperature in S1 is 150℃~250℃, and other point values ​​and range values ​​within the range of 100℃~280℃ will not be further listed here.

[0034] The method for preparing atomically porous graphene provided in this application involves exposing the graphene substrate to an ozone atmosphere of 100 ppm to 2000 ppm during the S1 oxidation treatment stage. Ozone preferentially reacts with the carbon-carbon double bonds in the crystal lattice, generating a large number of epoxy groups. These epoxy groups are not fixed at their initial formation sites but possess the ability to migrate along the crystal lattice. When the oxidation treatment temperature is controlled between 100℃ and 280℃, thermal excitation is sufficient to drive the epoxy groups to gradually migrate and aggregate into chains along specific lattice directions. As the epoxy chains lengthen, the local strain energy increases significantly, prompting structural rearrangement of adjacent epoxy groups. Ultimately, a strained ether core composed of ether bridges is formed at the oxygen cluster core, surrounded by oxygen-containing groups such as epoxy groups or hydroxyl groups, thus constructing a strained oxygen cluster precursor with a "core / shell" configuration.

[0035] The oxidation treatment temperature directly determines the epoxy migration rate and diffusion distance, thereby controlling the size of the oxygen cluster core: at lower temperatures, epoxy migration is limited, forming smaller ether nuclei, resulting in correspondingly smaller nanopore sizes generated by subsequent phosgenation; as the temperature rises to near 280℃, epoxy migration intensifies, the oxygen cluster cores grow sufficiently, and larger nanopores can be obtained. Ozone concentration dominates the nucleation density of oxygen clusters: at higher ozone concentrations, more initial sites for epoxy groups are simultaneously generated on the graphene surface, significantly increasing the number of strained oxygen clusters formed after thermal migration and aggregation, thus determining the pore density of the nanopores. During the S2 ultraviolet irradiation stage, photon energy selectively breaks the CO bonds in the highly strained ether nuclei, causing carbon atoms in the ether nucleus region to vaporize and escape as CO or CO2, leaving atomic-level vacancies. The peripheral epoxy, due to its lower migration energy barrier, does not directly vaporize under room temperature irradiation and can act as a stabilizer for dangling bonds at the pore edges. Because epoxy migration is much easier than ether migration, the oxidation stage can preferentially achieve long-range epoxy migration and precise control of oxygen cluster core size through thermal activation. Once the ether core is formed, it is quite stable, ensuring the localization of the photothermal vaporization location. Thus, oxidation temperature and ozone concentration achieve independent decoupling control of atomic-level nanopores from the two dimensions of pore size and pore density, respectively.

[0036] In some alternative embodiments, the oxidation treatment of the graphene substrate in an ozone atmosphere in S1 further includes oxidation treatment in an ozone atmosphere under the protection of an inert gas. As an example, the inert gas may be nitrogen, argon, helium, etc.

[0037] In some alternative embodiments, the ozone comprises a mixture of O3 and O2, with a volume ratio of O2 to O3 of (8~15):1; as an example, the volume ratio of O2 to O3 may be 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, etc.

[0038] In this application, the uniformity of pore size is further promoted by controlling the volume of O3 and O2 gases. During the S1 oxidation process, if the O3 concentration in the ozone is too high, the graphene substrate surface will generate extremely high density epoxy groups and various highly reactive oxygen species within a short period. This causes the epoxy groups to undergo random cross-linking or directly transform into more stable ether bonds before they have orderly migrated and aggregated. This disordered oxidation prevents the uniform formation of the "core / shell" structure of the strained oxygen clusters, resulting in a wider core size distribution. Consequently, the nanopores generated by subsequent phosgenation lose the regularity of temperature control, and the pore density is difficult to quantify precisely due to the chaotic initial nucleation sites. Conversely, if the O3 concentration in the ozone is too low, the oxidation rate is too slow, and the amount of epoxy groups generated is insufficient. This not only leads to a low nucleation density of strained oxygen clusters and an inability to effectively increase the pore density to the target range, but also, due to the reduced probability of epoxy group migration and collision, it is difficult to construct a complete strained ether core within a reasonable time, thus suppressing the upper limit of pore size control. This application precisely controls the volume ratio of O2 to O3 to (8~15):1, maintaining the oxidation reaction within a range of "moderate diffusion control and orderly surface reaction." This precisely defined volume ratio makes the oxidation temperature the key to independently controlling the pore size, while the ozone concentration becomes a specific factor for independently controlling the pore density. The two do not interfere with each other, fundamentally breaking the technical bottleneck of the mutual constraint between pore size and pore density in traditional methods. Simultaneously, the inert dilution effect of O2 as a buffer component effectively suppresses side reactions of gaseous free radicals, ensuring that the photothermal vaporization step selectively acts only on the high-strain ether core, guaranteeing the precise formation of angstrom-scale nanopores.

[0039] In some alternative embodiments, the ozone flow rate is 10 sccm to 30 sccm; as an example, the ozone flow rate can be any one or any two of 10 sccm, 12 sccm, 15 sccm, 18 sccm, 20 sccm, 22 sccm, 25 sccm, 30 sccm, etc., and is not limited herein.

[0040] In some optional embodiments, the oxidation treatment time is 2 min to 20 min; as an example, the oxidation treatment time can be any one or any two of 2 min, 5 min, 8 min, 10 min, 15 min, 18 min, 20 min, etc., and is not limited here.

[0041] In some optional embodiments, the photon energy of the ultraviolet light irradiated in S2 is 3.0 eV to 3.5 eV, the irradiation time is 5 s to 20 s, the electrical power is 5 W, and the optical power is 1200 mW. As an example, the photon energy of the ultraviolet light irradiated in S2 can be any one or any two of 3.0 eV, 3.1 eV, 3.2 eV, 3.3 eV, 3.4 eV, and 3.5 eV. The irradiation time can be any one or any two of 5 s, 6 s, 7 s, 8 s, 9 s, 10 s, 11 s, 12 s, 13 s, 14 s, 15 s, 16 s, 17 s, 18 s, 19 s, and 20 s.

[0042] The method for preparing atomically porous graphene provided in this application, through the synergistic effect of ozone concentration, oxidation temperature, and time, combined with specific ultraviolet irradiation conditions, further enhances the precision of atomically porous nanopores. Specifically, irradiating the graphene intermediate containing oxygen clusters with ultraviolet light at an energy of 3.0 eV to 3.5 eV for 5-20 s can further remove the strained ether cores, forming atomically porous nanopores. The strained ether cores, due to their large lattice strain, have an electronic structure that efficiently absorbs 3.0 eV to 3.5 eV photons. When irradiated with ultraviolet light at an energy of 3.0 eV to 3.5 eV, the strained ether cores absorb photon energy, and non-radiative retardation converts the energy into local lattice vibrational energy (thermal energy). The local high temperature triggers a chain reaction of ether core bond breaking, removing carbon atoms in the form of CO2, leaving precise angstrom-level nanopores. Compared to traditional high-temperature thermal vaporization methods, the ultraviolet irradiation operation provided in this application avoids epoxy diffusion, facilitates pore merging, and ensures the precision of the prepared atomically porous nanopores.

[0043] In some optional embodiments, the graphene substrate includes, but is not limited to, at least one of graphene, graphene oxide, reduced graphene oxide, element-doped graphene, and functionalized graphene. As an example, the graphene substrate may be reduced graphene oxide. The above-mentioned graphene substrates can be commercially available or can be prepared by methods known in the art. This application does not limit the source of the graphene substrate.

[0044] In some alternative embodiments, the graphene substrate may be in the form of at least one of two-dimensional film, powder, three-dimensional film, or fiber.

[0045] The second aspect of this application provides an atomically porous graphene, prepared according to the method described above. The atomically porous graphene provided by this application can utilize nanopores to construct longitudinal heat-conducting channels during high-temperature sintering, reducing structural damage caused by gas expansion, maintaining the dense stacked structure of the graphene film, and improving thermal conductivity.

[0046] In some optional embodiments, the atomically porous graphene has a specific surface area of ​​520 m². 2 / g~660m 2 / g; as an example, the specific surface area of ​​the atomic-level nanoporous graphene can be 520.96, 532.09, 539.30, 556.99, 558.21, 590.41, 610.58, 632.38, 654.33, etc.

[0047] Specific surface area testing methods include: The specific surface area of ​​atomic-level nanoporous graphene was measured using a JW-BK200B instrument under the following conditions: 250℃ / 2.5h treatment with high-purity nitrogen adsorption; the test method was in accordance with GB / T19077-2017.

[0048] In some optional embodiments, the difference between the thermal diffusivity of the atomically porous graphene and that of the graphene substrate is 150 mm. 2 / s~250mm 2 / s, and optionally, the difference between the thermal diffusivity of the atomic-level nanoporous graphene and the thermal diffusivity of the graphene substrate can be 203 mm. 2 / s. The difference between the thermal diffusivity of the atomic-level nanoporous graphene and that of the graphene substrate is represented by Δκ, where Δκ = thermal diffusivity of atomic-level nanoporous graphene - thermal diffusivity of graphene substrate.

[0049] The thermal diffusivity of atomic-level nanoporous graphene in this application was measured using the In-Plane mode measurement method described in the standard QGDMR 04-2023 "Laser flare method for testing thermal conductivity". The specific steps involved in the In-Plane mode measurement method may include: (1) Sample preparation: 1) Take the prepared atomic-level nanoporous graphene and cut a circular sample with a diameter of about 25.4 mm using a suitable die-cutting machine or die-cutting tool.

[0050] 2) Use a micrometer or digital thickness gauge to accurately measure the thickness of the sample.

[0051] 3) Place the sample into the In-Plane holder, then place the holder into the 25.4 mm circular standard holder, and place it into the instrument for testing.

[0052] 4) Set the instrument parameters. The instrument settings are as follows: Test temperature: 25°C Temperature threshold (tolerance / stability threshold): 0.3K Number of flash points: 5 or more Voltage: 260V Pulse width: 50μs Main gain: 5087 (If the highest point of the temperature rise curve is found to exceed 9V, it can be reduced to 3000). Sampling time: 30 ms (adjustable, but in principle about 10 times the half-heating time (t50)) Detection area: 14 mm The thermal diffusivity of the graphene substrate and the prepared atomic-level nanoporous graphene were tested using the methods described above.

[0053] It should be noted that when the graphene substrate is in powder form, the sample needs to be calendered before testing the thermal diffusivity.

[0054] A third aspect of this application provides an application of atomically nanoporous graphene for use in supercapacitors, gas molecular sieves, thermally conductive components, and thermally insulating components.

[0055] Alternatively, when atomic-scale nanoporous graphene is used in supercapacitors, its high specific surface area and conductivity, along with the atomic-scale nanopores, provide a fast ion transport channel for the supercapacitor.

[0056] As a further option, when atomic-level nanoporous graphene is used in gas molecular sieves, the atomic-level nanopores can be used to sieve gas molecules. Atomic-level nanoporous graphene has good ethane retention and high ethylene throughput, and can be used for selective sieving of ethane and ethylene.

[0057] Alternatively, when atomic-level nanoporous graphene is used in thermal insulation components, the dangling bonds in the nanoporous structure on the surface of atomic-level nanoporous graphene can be used to enhance the interaction between interfacial carbon atoms and the atoms of the materials in the thermal insulation component, thereby reducing interfacial thermal resistance.

[0058] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0059] Example 1 S1: 5g of reduced graphene oxide powder was placed in a reaction apparatus and protected with high-purity argon gas at a flow rate of 200 sccm. The temperature was then raised to 250℃ and held for 60 min. A mixture of O3 and O2 gas (flow rate of 20 sccm, volume ratio of O2:O3 10:1) was then introduced, and oxidation was performed at 250℃ for 10 min to obtain a graphene intermediate containing oxygen clusters. S2: After oxidation, high-purity argon gas is vaporized, the reaction equipment is removed, and after the temperature of the graphene intermediate containing oxygen clusters drops to room temperature, it is irradiated for 10 seconds using a Taihong Optoelectronics UV lamp (model 3535UV385, photon energy 3.2eV, electrical power 5W, optical power 1200mW) to form atomic-level nanopores, thus obtaining atomic-level nanoporous graphene (a reduced graphene oxide sample with atomic-level nanoporous pores) (see... Figure 1 ).

[0060] Examples 2-9 and Comparative Examples 1-4 are implemented in the same way as Example 1, and the differences from Example 1 are shown in Table 1.

[0061] Table 1: Examples and Comparative Examples

[0062] Performance testing (1) Specific surface area: The specific surface area of ​​atomic-level nanoporous graphene was tested using a JW-BK200B instrument. The test conditions were: 250℃ / 2.5h treatment, and high-purity nitrogen was used for adsorption. The test method was in accordance with GB / T19077-2017.

[0063] (2) Thermal diffusivity: The thermal diffusivity was measured using the In-Plane mode measurement method described in standard QGDMR 04-2023 "Laser flash method for measuring thermal conductivity". The specific steps involved in the In-Plane mode measurement method include: (1) Sample preparation: 1) Take the prepared atomic-level nanoporous graphene and cut a circular sample with a diameter of about 25.4 mm using a suitable die-cutting machine or die-cutting tool.

[0064] 2) Use a micrometer or digital thickness gauge to accurately measure the thickness of the sample.

[0065] 3) Place the sample into the In-Plane holder, then place the holder into the 25.4 mm circular standard holder, and place it into the instrument for testing.

[0066] 4) Set the instrument parameters. The instrument settings are as follows: Test temperature: 25°C Temperature threshold (tolerance / stability threshold): 0.3K Number of flash points: 5 or more Voltage: 260V Pulse width: 50μs Main gain: 5087 (If the highest point of the temperature rise curve is found to exceed 9V, it can be reduced to 3000). Sampling time: 30 ms (adjustable, but in principle about 10 times the half-heating time (t50)) Detection area: 14 mm The thermal diffusivity of the graphene substrate and the prepared atomic-level nanoporous graphene were tested using the methods described above.

[0067] The difference between the thermal diffusivity of atomic-level nanoporous graphene and the thermal diffusivity of the graphene substrate is represented by Δκ, where Δκ = thermal diffusivity of atomic-level nanoporous graphene - thermal diffusivity of the graphene substrate.

[0068] The specific test results are shown in Table 2.

[0069] Table 2: Test Results

[0070] The atomic-level nanopore preparation method provided by this invention exhibits an interrelationship among BET value, Δκ value, and pore size. In Examples 1-3, under the same working gas (O2 / O3) flow rate, a higher O3 ratio results in more oxygen clusters, leading to more atomic-level nanopores and an increased specific surface area. In Examples 1, 4, 5, and Comparative Example 2, under the same conditions, a higher oxidation temperature results in larger and more numerous oxygen clusters, correspondingly larger pore sizes. While an increase in pore size may decrease the specific surface area to some extent, an increase in the number of clusters can improve the specific surface area; these two factors are in a competitive relationship. In Examples 5-7, at higher oxidation temperatures, a longer oxidation time increases the number of oxygen clusters formed, resulting in both large and small oxygen clusters. Although this increases the number of pores after photolithography, the larger pores also simultaneously weaken the specific surface area. In Examples 1, 8, and 9, under the same conditions, the photoirradiation time only affects the etching depth and ratio of oxygen clusters; a longer photoirradiation time results in deeper oxygen clusters being etched, increasing the specific surface area. In addition, thermal conductivity is related to the size and density of pores. When using atomic-level nanoporous graphene prepared in this application, the overall migration of carbon atoms during the graphitization stage is beneficial to drive the repair of defects, thus improving thermal conductivity. If the pore density of atomic-level nanoporous graphene is high or the pore size is large, the migration of carbon atoms is insufficient to repair the pore defects, forming phonon scattering traps, and the thermal conductivity decreases.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing atomically porous graphene, characterized in that, Includes the following steps: S1: The graphene substrate is placed in an ozone atmosphere for oxidation treatment to obtain a graphene intermediate with oxygen clusters. S2: The graphene intermediate containing oxygen clusters is irradiated with ultraviolet light at room temperature to form atomic-level nanoporous graphene. The atomically porous graphene has a pore size of 2 Å to 6 Å and a pore density of 0.1 × 10⁻⁶. 12 cm 2 ~10×10 12 cm 2 ; The concentration of ozone is 100ppm to 2000ppm; The oxidation treatment temperature described in S1 is 100℃~280℃.

2. The preparation method according to claim 1, characterized in that, The ozone satisfies at least one of the following conditions: (1) The ozone comprises a mixture of O3 and O2, wherein the volume ratio of O2 to O3 is (8~15):1; (2) The flow rate of ozone is 10 sccm to 30 sccm.

3. The preparation method according to claim 1, characterized in that, The oxidation treatment time is 2 min to 20 min.

4. The preparation method according to claim 1, characterized in that, The ultraviolet irradiation in S2 satisfies at least one of the following conditions: (1) The photon energy of ultraviolet light is 3.0 eV~3.5 eV; (2) Irradiation time is 5s~20s; (3) The power is 5W; (4) The optical power is 1000mW~10000mW.

5. The preparation method according to claim 1, characterized in that, The graphene substrate includes at least one of graphene, graphene oxide, reduced graphene oxide, element-doped graphene, and functionalized graphene.

6. The preparation method according to claim 5, characterized in that, The graphene substrate may be in the form of at least one of two-dimensional film, powder, three-dimensional film or fiber.

7. An atomically nanoporous graphene, characterized in that, Prepared according to the method according to any one of claims 1 to 6.

8. The atomic-level nanoporous graphene according to claim 7, characterized in that, The specific surface area of ​​the atomically porous graphene is 520 m². 2 / g~660m 2 / g.

9. The atomic-level nanoporous graphene according to claim 7, characterized in that, The difference between the thermal diffusivity of the atomic-level nanoporous graphene and that of the graphene substrate is 150 mm. 2 / s~250mm 2 / s.

10. An application of atomically nanoporous graphene according to any one of claims 7 to 9, characterized in that, Used in supercapacitors, gas molecular sieves, thermal conductive components, and thermal insulation components.

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