Preparation method of cobalt-nickel-loaded graphene wave-absorbing material

Abstract

The present application relates to the technical field of graphene preparation, in particular to a preparation method of graphene wave-absorbing material based on cobalt-nickel loading, comprising the following steps: S1, raw material preparation; S2, graphene dispersion liquid preparation; S3, metal ion solution preparation; S4, mixed solution preparation; S5, hydrothermal reaction; S6, filtration and washing; S7, vacuum drying. The filtration and washing device is involved in step S6; the filtration and washing device is used for filtering and washing the mixed solution after the hydrothermal reaction. The filtration and washing device of the present application adopts the way of pressurized filtration and washing to make the mixed solution be fully filtered and washed, and the filtration and washing of the mixed solution are both completed by the filtration and washing device, thereby increasing the efficiency of the preparation of the graphene wave-absorbing material based on cobalt-nickel loading; the lower pressing assembly of the present application can perform a lower pressing action on the filter membrane, so that the filter membrane is tightly attached to the bottom of the filter cavity, and the filter membrane can be quickly replaced through the lower pressing assembly.

Description

Technical Field

[0001] This invention relates to the field of graphene preparation technology, specifically a method for preparing cobalt-nickel-supported graphene microwave absorbing materials. Background Technology

[0002] With the rapid development of communication technology, while bringing convenience to people's lives, electromagnetic radiation has also become a new source of pollution for the ecological environment. With the widespread use of electromagnetic devices in our daily lives and the rapid development of the wireless communication industry, the resulting electromagnetic pollution has a huge impact on the environment and human health.

[0003] Microwave absorbing materials, or simply microwave absorbing materials, refer to materials that absorb electromagnetic wave energy projected onto their surface and convert that energy into heat or other forms of energy through the dielectric loss of the material. Cobalt-nickel-loaded graphene microwave absorbing materials are currently a common type of microwave absorbing material. They not only possess the excellent electrical and thermal conductivity of graphene, but the addition of cobalt-nickel nanoparticles significantly improves the material's microwave absorption performance. Currently, cobalt-nickel-loaded graphene microwave absorbing materials are generally prepared using hydrothermal methods, chemical vapor deposition, sol-gel methods, electrochemical deposition methods, and electrochemical deposition methods. Among these, the hydrothermal method is the most common. The preparation of cobalt-nickel-loaded graphene microwave absorbing materials using the hydrothermal method includes steps such as raw material preparation, graphene dispersion preparation, metal ion solution preparation, mixed solution preparation, hydrothermal reaction, filtration and washing, and vacuum drying. Among these, filtration and washing is a crucial step.

[0004] The conventional procedure for filtering and washing cobalt-nickel-loaded graphene microwave absorbing materials is as follows: the mixed solution is filtered through a filter, and after filtration, a solid material is obtained. This solid material is then washed multiple times using an elution machine to remove residual solution and unreacted substances. Finally, the washed solid material is collected. However, the existing filtration and washing procedures for preparing cobalt-nickel-loaded graphene microwave absorbing materials have the following problems.

[0005] First, the filtration and washing of the mixed solution need to be carried out separately, which is not conducive to the operation of filtration and washing of the mixed solution, and also results in low preparation efficiency. Second, when the mixed solution is filtered, the filter membrane may break due to the gravity of the solution, and the mixed solution is prone to local pore blockage, resulting in low filtration efficiency. Solid matter tends to accumulate in certain positions, thus affecting the overall filtration effect of the mixed solution. Furthermore, the solid matter cannot be evenly contacted with the washing solution during the washing process, resulting in some solid matter not being washed thoroughly, which in turn affects the purity of the final product. Summary of the Invention

[0006] The present invention adopts the following technical solution to solve the above-mentioned technical problems. The preparation method of graphene microwave absorbing material based on cobalt and nickel load includes the following steps: S1, raw material preparation: prepare graphene material, cobalt source and nickel source, wherein the graphene material is reduced graphene oxide, the cobalt source is cobalt nitrate hexahydrate and the nickel source is nickel nitrate hexahydrate.

[0007] S2. Preparation of graphene dispersion: An appropriate amount of reduced graphene oxide is dispersed in deionized water and then ultrasonically dispersed to obtain a graphene dispersion.

[0008] S3. Preparation of metal ion solution: Dissolve appropriate amounts of cobalt nitrate hexahydrate and nickel nitrate hexahydrate in deionized water to form a metal ion solution.

[0009] S4. Preparation of mixed solution: Add the metal ion solution to the graphene dispersion and stir thoroughly to obtain a mixed solution.

[0010] S5. Hydrothermal reaction: Transfer the mixed solution to a high-pressure reactor, seal it, place it in an oven, and perform a hydrothermal reaction at a certain temperature for several hours.

[0011] S6. Filtration and washing: After the hydrothermal reaction is completed, the mixed solution is filtered and separated by a filtration and washing device, and then washed multiple times with deionized water and ethanol to remove unreacted raw materials and by-products.

[0012] S7. Vacuum drying: The washed product is collected and placed in a vacuum drying oven to dry, thus obtaining cobalt-nickel loaded graphene microwave absorbing material.

[0013] The filtration and washing device is used to filter and wash the mixed solution after the hydrothermal reaction. The filtration and washing device includes a pressure chamber and a feeding chamber rotatably connected to the bottom of the pressure chamber. A filtration chamber is provided on one side of the pressure chamber. A square notch is opened at the bottom of the filtration chamber. A filter membrane is laid on the square notch. A filter feeding chamber and a washing feeding chamber are respectively provided on both sides of the feeding chamber. The filter feeding chamber or the washing feeding chamber corresponds to the position of the square notch. A filter hammer is provided in the filter feeding chamber to hammer the filter membrane. A washing scraper is provided in the washing feeding chamber to scrape the filter membrane. The filter hammer and the washing scraper prevent the filter membrane from clogging during the filtration and washing of the mixed solution.

[0014] Preferably, a positioning slot is provided on the outer surface of the filter membrane, and a corresponding insertion post is slidably provided at the bottom of the filter cavity. The side of the insertion post corresponding to the side wall of the filter cavity is connected to the corresponding side wall of the filter cavity through an elastic element.

[0015] Preferably, a pressure cover is sealed and installed on the top of the pressure chamber and above the filter chamber, and a pressing component is provided inside the filter chamber to press the filter membrane tightly against the bottom of the filter chamber.

[0016] Preferably, the pressing assembly includes a pressing frame disposed within the filter chamber and located within the structure formed by the insert post. The size of the pressing frame is larger than the size of the square notch. Both ends of the pressing frame are connected to L-shaped brackets. The top of each L-shaped bracket is connected to a pressing elastic rod. A support plate is installed on the side wall of the filter chamber. The upper end of the pressing elastic rod is installed at the bottom of the support plate.

[0017] Preferably, an annular groove and an annular slider are provided between the pressurization chamber and the unloading chamber for mutual rotational cooperation. A locking slot is provided at the bottom of the pressurization chamber, and a locking block is slidably provided at the top of the unloading chamber corresponding to the position of the locking slot.

[0018] Preferably, the filter hammer and the washing scraper both include a support assembly. The support assembly includes a cylinder installed inside the feeding hopper, a support horizontal plate installed on the telescopic end of the cylinder, and support vertical plates installed at equal intervals on the support horizontal plate. A top extension column is distributed on both sides of the support horizontal plate. One section of the top extension column is connected to the support horizontal plate through a guide telescopic rod, and the other end of the top extension column is slidably connected to the support horizontal plate through a guide column.

[0019] Preferably, the filter hammer further includes multiple hammering components installed on the support horizontal plate inside the filter discharge chamber, with one hammering component distributed between every two support vertical plates. The hammering component includes hammering connecting plates symmetrically installed on both sides of the support horizontal plate inside the filter discharge chamber. Each hammering connecting plate is slidably connected to a hammering connecting rod. A hammering plate is installed on the top of the two hammering connecting rods. A hammering guide block is installed at the bottom of the hammering connecting rod. A hammering spring is sleeved on the outer side of the upper end of the hammering connecting rod and between the hammering connecting plate and the hammering plate. A mating block is installed on the top extension column corresponding to the position of the hammering guide block.

[0020] Preferably, the top of the hammering plate is uniformly provided with hammering blocks of a frustum-shaped structure, and multiple mating blocks are provided, and the positions of the mating blocks and the top extension column are all parallelogram structures.

[0021] Preferably, the washing scraper further includes multiple scraping components installed between two adjacent support vertical plates in the washing discharge chamber. Each scraping component includes a support guide rod installed between two adjacent support vertical plates in the washing discharge chamber. A scraping vertical plate is slidably connected to the outside of the support guide rod. A scraper is mounted on the top of the scraping vertical plate via a rotating shaft. A return spring is connected between one side of the scraping vertical plate and the corresponding support vertical plate. A toggle rod is installed at both ends of the scraping vertical plate. A push block is provided at the position of the top extension column corresponding to the lower end of the toggle rod.

[0022] Preferably, the top of the scraper is provided with a wave-shaped protrusion, and a friction plate is distributed on both sides of the rotating shaft. The friction plate is installed between two adjacent support vertical plates in the washing and feeding chamber. The opposite sides of the two friction plates are provided with interlocking friction blocks. When the rotating shaft contacts the friction block, the friction block drives the rotating shaft to rotate.

[0023] The beneficial effects of the present invention are as follows: First, the filtration and washing device of the present invention adopts pressure filtration and washing to ensure that the mixed solution is fully filtered and washed, and the filtration and washing of the mixed solution are both completed by the filtration and washing device, thereby increasing the efficiency of the preparation of cobalt-nickel loaded graphene absorbing material.

[0024] Second, the pressing component of the present invention can press down on the filter membrane, so that the filter membrane is tightly attached to the bottom of the filter chamber, and the filter membrane can be quickly replaced through the pressing component.

[0025] Third, the insertion post of the present invention, in conjunction with the positioning slot of the filter membrane, enables the filter membrane to be positioned quickly. When the filter membrane is subjected to greater pressure, it will transfer the force to the insertion post, causing the insertion post to undergo a small displacement. The sliding generated by the insertion post prevents the filter membrane from rupturing.

[0026] Fourth, the support component of the present invention is used to support the bottom of the filter membrane, so that the bottom of the filter membrane is supported. When filtering or washing, the filter membrane will deform under pressure, so that its bottom rests on the top of multiple support vertical plates and forms several filter channels under the action of two adjacent support vertical plates. As the cylinder moves in extension and retraction, the support vertical plates will move, so that the position of the filter channels formed by two adjacent support vertical plates will change. As a result, the solid material on the upper side of the filter membrane will not always accumulate in one place, thereby increasing the filtering and washing effect of the present invention.

[0027] 5. The hammering component of the present invention is used to repeatedly hammer or push different positions on the bottom of the filter membrane during the movement of the support component, so as to prevent solid matter from always accumulating in a specific position of the filter membrane, thereby preventing the filter membrane from becoming blocked.

[0028] VI. The scraping component of the present invention is used to scrape the bottom of the filter membrane during the movement of the support component, so that the solid material can fully contact the cleaning liquid, thereby increasing the washing effect of the present invention on the solid material. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0030] Figure 1 This is a flowchart of the preparation method of the cobalt-nickel-supported graphene microwave absorbing material of the present invention.

[0031] Figure 2This is a schematic diagram of the structure of the filtration and washing device of the present invention.

[0032] Figure 3 This is a schematic diagram of the structure of the filter washing device of the present invention after the pressure cover is removed.

[0033] Figure 4 This is a top view of the filter washing device of the present invention after the pressure cover has been removed.

[0034] Figure 5 This is a partial cross-sectional view of the pressurization chamber in the filtration and washing device of the present invention.

[0035] Figure 6 This is a schematic diagram of the material feeding hopper in the filtration and washing device of the present invention.

[0036] Figure 7 This is a schematic diagram of the structure of the feed hopper after partial dissection in the filter washing device of the present invention.

[0037] Figure 8 This is a first structural diagram of the support component and the hammering component in the filter washing device of the present invention.

[0038] Figure 9 This is a second structural diagram of the support component and the hammering component in the filter washing device of the present invention.

[0039] Figure 10 This is a first structural diagram of the support component and the scraping component in the filter washing device of the present invention.

[0040] Figure 11 This is a second structural diagram of the support component and the scraping component in the filter washing device of the present invention.

[0041] Figure 12 This is a schematic diagram of the structure of the filter washing device of the present invention, in which the supporting vertical plate and the hammer block divide the filter membrane into several filter channels.

[0042] In the diagram: 1. Pressure chamber; 11. Filter chamber; 12. Filter membrane; 13. Insert column; 14. Lower pressure frame; 15. L-shaped bracket; 16. Lower pressure elastic rod; 17. Support plate; 18. Pressure cover; 19. Locking slot; 2. Discharge bin; 21. Filter discharge chamber; 22. Washing discharge chamber; 3. Support assembly; 31. Cylinder; 32. Support horizontal plate; 33. Support vertical plate; 34. Top extension column; 341. Mating block; 342. Pushing block; 35. Guide telescopic rod; 36. Guide column; 4. Hammering assembly; 41. Hammering connecting plate; 42. Hammering connecting rod; 43. Hammering plate; 44. Hammering guide block; 45. Hammering spring; 46. Hammering block; 5. Scraping assembly; 51. Support guide rod; 52. Scraping vertical plate; 53. Scraper; 54. Return spring; 55. Actuating rod; 56. Friction plate. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] See Figure 1 A method for preparing cobalt-nickel-supported graphene microwave absorbing material includes the following steps: S1, raw material preparation: prepare graphene material, cobalt source, and nickel source, wherein the graphene material is reduced graphene oxide, the cobalt source is cobalt nitrate hexahydrate, and the nickel source is nickel nitrate hexahydrate.

[0045] S2. Preparation of graphene dispersion: An appropriate amount of reduced graphene oxide is dispersed in deionized water and then ultrasonically dispersed to obtain a graphene dispersion.

[0046] S3. Preparation of metal ion solution: Dissolve appropriate amounts of cobalt nitrate hexahydrate and nickel nitrate hexahydrate in deionized water to form a metal ion solution.

[0047] S4. Preparation of mixed solution: Add the metal ion solution to the graphene dispersion and stir thoroughly to obtain a mixed solution.

[0048] S5. Hydrothermal reaction: Transfer the mixed solution to a high-pressure reactor, seal it, place it in an oven, and hydrothermally react it at a certain temperature for five hours.

[0049] S6. Filtration and washing: After the hydrothermal reaction is completed, the mixed solution is filtered and separated by a filtration and washing device, and then washed multiple times with deionized water and ethanol to remove unreacted raw materials and by-products.

[0050] S7. Vacuum drying: The washed product is collected and placed in a vacuum drying oven to dry, thus obtaining cobalt-nickel loaded graphene microwave absorbing material.

[0051] See Figures 3-6The filtration and washing device is used to filter and wash the mixed solution after the hydrothermal reaction. The filtration and washing device includes a pressure chamber 1 and a feeding chamber 2 rotatably connected to the bottom of the pressure chamber 1. A filter chamber 11 is provided on one side of the pressure chamber 1. A square notch is opened at the bottom of the filter chamber 11, and a filter membrane 12 is laid on the square notch. A filter feeding chamber 21 and a washing feeding chamber 22 are respectively provided on both sides of the feeding chamber 2. The filter feeding chamber 21 or the washing feeding chamber 22 corresponds to the position of the square notch. A filter hammer is provided in the filter feeding chamber 21 to hammer the filter membrane 12. A washing scraper is provided in the washing feeding chamber 22 to scrape the filter membrane 12. The filter hammer and the washing scraper prevent the filter membrane 12 from clogging during the filtration and washing of the mixed solution. The filtration and washing device uses pressure to ensure that the mixed solution is fully filtered and washed. The filtration and washing of the mixed solution are both completed by the filtration and washing device, which increases the efficiency of the preparation of cobalt-nickel loaded graphene absorbing material.

[0052] Specifically, the pressurization chamber 1 is first sealed and pressurized. Then, the mixed solution is transferred to the filter chamber 11. Under the filtration of the filter membrane 12, the solid matter in the mixed solution is blocked above the filter membrane 12. The liquid part of the mixed solution is discharged through the square notch and the filter discharge chamber 21. At the same time, the filter hammer in the filter discharge chamber 21 can hammer the lower side of the filter membrane 12, so that the solid matter above the filter membrane 12 can be evenly distributed and prevent the solid matter from clogging the filter membrane 12, increasing the filtration speed of the mixed solution. After the mixed solution is filtered, the discharge chamber 2 is rotated 180 degrees so that the washing discharge chamber 22 corresponds to the square notch. Then, the solid matter on the filter membrane 12 is thoroughly washed with deionized water and ethanol respectively. During the washing process, the washing scraper scrapes the lower side of the filter membrane 12, so that the solid matter can be fully washed and the solid matter is prevented from accumulating on one side of the filter membrane 12, which would cause incomplete washing of the solid matter.

[0053] See Figure 2 For example, a pressure hood 18 is sealed and installed on the top of the pressure chamber 1 and above the filter chamber 11. The pressure hood 18 is used to connect the pressure chamber 1 to an external air source and to introduce the mixed solution or cleaning fluid into the filter chamber 11.

[0054] See Figure 2 , Figure 5 and Figure 6 The pressurization chamber 1 and the unloading chamber 2 are provided with an annular sliding groove and an annular slider that rotate and cooperate with each other. The bottom of the pressurization chamber 1 is provided with a locking slot 19. The top of the unloading chamber 2 is provided with a locking block that slides in the position corresponding to the locking slot 19. When the unloading chamber 2 rotates 180 degrees, the locking block is inserted into the locking slot 19 to increase the accuracy of the unloading chamber 2 after rotation.

[0055] See Figure 3 and Figure 4 Since the filter membrane 12 is a consumable, it needs to be replaced frequently. To prevent the filter membrane 12 from not being able to fit tightly against the bottom of the filter chamber 11, the present invention adopts the following structure: a pressing component is provided in the filter chamber 11 to press the filter membrane 12 down so that the filter membrane 12 fits tightly against the bottom of the filter chamber 11. The pressing component can press the filter membrane 12 down so that the filter membrane 12 fits tightly against the bottom of the filter chamber 11, and the pressing component can also make the filter membrane 12 quickly replaceable.

[0056] See Figure 4 and Figure 5 To prevent the filter membrane 12 from breaking or being damaged under pressure, the present invention sets the filter membrane 12 to a structure that can make a small displacement. A positioning slot is provided on the outer surface of the filter membrane 12. A corresponding insertion post 13 is slidably provided at the bottom of the filter cavity 11. The side of the insertion post 13 corresponding to the side wall of the filter cavity 11 is connected to the corresponding side wall of the filter cavity 11 through an elastic element. The insertion post 13 cooperates with the positioning slot of the filter membrane 12 to enable the filter membrane 12 to be positioned quickly. When the filter membrane 12 is under great pressure, the force will be transmitted to the insertion post 13, causing the insertion post 13 to make a small displacement. When the insertion post 13 abuts against the outside of the lower pressure frame 14, the insertion post 13 will no longer move to the position of the square notch, thereby preventing the filter membrane 12 from falling off. The sliding of the insertion post 13 also prevents the filter membrane 12 from breaking.

[0057] See Figure 3 and Figure 5 For example, the pressing assembly includes a pressing frame 14 disposed within the filter chamber 11 and located within the structure formed by the insert post 13. The size of the pressing frame 14 is larger than the size of the square notch. Both ends of the pressing frame 14 are connected to L-shaped brackets 15. The top of each L-shaped bracket 15 is connected to a pressing elastic rod 16. A support plate 17 is installed on the side wall of the filter chamber 11. The upper end of the pressing elastic rod 16 is installed at the bottom of the support plate 17. Under the action of the pressing elastic rod 16, the pressing frame 14 presses down on the filter membrane 12. When the filter membrane 12 needs to be replaced, the pressing elastic rod 16 is lifted upward to remove the old filter membrane 12, and the new filter membrane 12 is re-laid on the square notch. Then the external force is removed, so that the pressing frame 14 presses down on the filter membrane 12 again.

[0058] It is understandable that during pressure filtration, the filter membrane 12 will deform to a certain extent due to the pressure and the impact of the mixed solution or cleaning fluid.

[0059] See Figures 6-8The filter hammer and the washing scraper both include a support assembly 3. The support assembly 3 includes a cylinder 31 installed inside the feeding hopper 2, a support horizontal plate 32 installed on the telescopic end of the cylinder 31, and support vertical plates 33 installed at equal intervals on the support horizontal plate 32. A top extension column 34 is distributed on both sides of the support horizontal plate 32. One section of the top extension column 34 is connected to the support horizontal plate 32 through a guide telescopic rod 35, and the other end of the top extension column 34 is slidably connected to the support horizontal plate 32 through a guide column 36. The support assembly 3 is used to support the bottom of the filter membrane 12 and increase the filtration and washing effect of the present invention.

[0060] Specifically, during filtration or washing operations, the filter membrane 12 deforms under pressure, causing its bottom to rest on top of multiple support vertical plates 33, and forming several filtration channels (e.g., ...) under the action of two adjacent support vertical plates 33. Figure 12 As shown, as the cylinder 31 extends and retracts, the support plate 33 moves, causing the filter channel formed by two adjacent support plates 33 to change position. Therefore, the solid matter on the upper side of the filter membrane 12 will not always accumulate in one place, which increases the filtration and washing effect of the present invention.

[0061] It should be noted that, in order to avoid the support plate 32 connected to the cylinder 31 from forming a cantilever beam structure, the present invention provides a support rod at the end of the support plate 32 away from the cylinder 31. The support rod is inserted inside the feeding bin 2, thereby increasing the stability of the support plate 32.

[0062] See Figure 7 , Figure 8 and Figure 9 The filter hammering component also includes multiple hammering assemblies 4 installed on the support horizontal plate 32 inside the filter feeding chamber 21, with one hammering assembly 4 distributed between every two support vertical plates 33. The hammering assembly 4 includes hammering connecting plates 41 symmetrically installed on both sides of the support horizontal plate 32 inside the filter feeding chamber 21. Each hammering connecting plate 41 is slidably connected to a hammering connecting rod 42. A hammering plate 43 is installed on the top of the two hammering connecting rods 42. A hammering guide block 44 is installed at the bottom of the hammering connecting rod 42. A hammering spring 45 is sleeved on the outer side of the upper end of the hammering connecting rod 42 between the hammering connecting plate 41 and the hammering plate 43. A mating block 341 is installed on the top extension column 34 at the position corresponding to the hammering guide block 44. Multiple mating blocks 341 are provided, and the positions of the mating blocks 341 and the top extension column 34 are all parallelogram structures. The hammering assembly 4 is used to perform cyclic hammering or extension on different positions at the bottom of the filter membrane 12 during the movement of the support assembly 3 to prevent the filter membrane 12 from becoming clogged.

[0063] Specifically, when the cylinder 31 extends, the supporting horizontal plate 32 moves to the right. When the right end of the top extension column 34 abuts against the right side wall of the filter discharge chamber 21, as the supporting horizontal plate 32 continues to move to the right, the top extension column 34 and the supporting horizontal plate 32 move relative to each other left and right. This causes the cooperating block 341 to drive the hammer guide block 44 to move downward, causing the hammer connecting rod 42 to drive the hammer spring 45 to compress. When the cooperating block 341 separates from the hammer guide block 44, the hammer spring 45 releases its elastic force and... The moving hammer plate 43 hammers the bottom of the filter membrane 12, and multiple mating blocks 341 drive the mating blocks 341 to continuously hammer the filter membrane 12. When the cylinder 31 retracts, the mating blocks 341 can lift the hammer guide block 44 upward, so that the hammer plate 43 pushes the bottom of the filter membrane 12 multiple times. Then, when the cylinder 31 moves in extension and retraction, it drives the hammer plate 43 to perform a dual action of hammering and pushing the filter membrane 12, further reducing the probability of the filter membrane 12 becoming clogged.

[0064] It should be noted that the top of the hammer plate 43 is uniformly provided with hammer blocks 46 of a frustum-shaped structure. The contact area between the hammer blocks 46 and the filter membrane 12 is smaller, which makes the force of hammering and pushing the filter membrane 12 greater, thereby increasing the filtration effect of the present invention on the mixed solution.

[0065] See Figure 6 , Figure 10 and Figure 11 The washing scraping mechanism also includes multiple scraping assemblies 5 installed between two adjacent support vertical plates 33 within the washing discharge chamber 22. Each scraping assembly 5 includes a support guide rod 51 installed between two adjacent support vertical plates 33 within the washing discharge chamber 22. A scraping vertical plate 52 is slidably connected to the outer side of the support guide rod 51. A scraper 53 is mounted on the top of the scraping vertical plate 52 via a rotating shaft. A return spring 54 connects one side of the scraping vertical plate 52 to the corresponding support vertical plate 33. A toggle rod 55 is installed at both ends of the scraping vertical plate 52, and a top extension column 34... A push block 342 is provided at the lower end of the corresponding toggle lever 55; a friction plate 56 is distributed on both sides of the rotating shaft. The friction plate 56 is installed between two adjacent support vertical plates 33 in the washing and feeding chamber 22. The two friction plates 56 have intersecting friction blocks on their opposite sides. When the rotating shaft contacts the friction block, the friction block drives the rotating shaft to rotate; the scraping component 5 is used to scrape the bottom of the filter membrane 12 during the movement of the support component 3, so that the solid material can fully contact the cleaning liquid, thereby increasing the washing effect of the present invention on the solid material.

[0066] Specifically, when the cylinder 31 extends, the top extension column 34 and the support plate 32 move relative to each other left and right, thereby pushing the block 342 to move the lever 55 to the left. The lever 55 drives the scraping plate 52 to move synchronously. The rotating shaft at the upper end of the scraping plate 52 cooperates with the friction plate 56, so that the rotating shaft drives the scraper 53 to move and reciprocate. Under the scraping action of the scraper 53, the solid matter on the filter membrane 12 can be dispersed, and the solid matter can be fully washed, reducing the residue of unreacted substances and by-products, and increasing the washing effect of solid matter. When the cylinder 31 retracts, the scraping plate 52 returns to the initial position under the restoring force of the return spring 54, and the scraper 53 can also continue to scrape the lower side of the filter membrane 12 during the process of the scraping plate 52 returning to the initial position.

[0067] It should be noted that the top of the scraper 53 is provided with a wave-shaped protrusion. The wave-shaped protrusion on the scraper 53 can reduce the contact area between the scraper 53 and the filter membrane 12. Under the rotation of the scraper 53, the wave-shaped protrusion can scrape the underside of the filter membrane 12 evenly, further increasing the washing effect of the solid material. After the solid material is washed, the pressure cover 18 is removed and the filter membrane 12 is taken out from the pressure chamber 1, and then the prepared cobalt-nickel loaded graphene absorbing material is collected.

[0068] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing cobalt-nickel-supported graphene microwave absorbing material, comprising the following steps: S1. Raw material preparation: Prepare graphene material, cobalt source, and nickel source, wherein the graphene material is reduced graphene oxide, the cobalt source is cobalt nitrate hexahydrate, and the nickel source is nickel nitrate hexahydrate. S2. Preparation of graphene dispersion: An appropriate amount of reduced graphene oxide is dispersed in deionized water and then ultrasonically dispersed to obtain a graphene dispersion. S3. Preparation of metal ion solution: Dissolve appropriate amounts of cobalt nitrate hexahydrate and nickel nitrate hexahydrate in deionized water to form a metal ion solution; S4. Preparation of mixed solution: Add the metal ion solution to the graphene dispersion and stir thoroughly to obtain a mixed solution; S5. Hydrothermal reaction: Transfer the mixed solution to a high-pressure reactor, seal it, place it in an oven, and hydrothermally react it for five hours at a preset temperature. S6. Filtration and washing: The mixed solution after the hydrothermal reaction is completed is filtered and separated by a filtration and washing device, and then washed multiple times with deionized water and ethanol to remove unreacted raw materials and by-products. S7. Vacuum drying: The washed product is collected and placed in a vacuum drying oven to dry, thus obtaining cobalt-nickel loaded graphene absorbing material. The filter and wash device is characterized in that it is used to filter and wash the mixed solution after the hydrothermal reaction. The filter and wash device includes a pressure chamber and a feeding chamber rotatably connected to the bottom of the pressure chamber. A filter chamber is provided on one side of the pressure chamber. A square notch is opened at the bottom of the filter chamber. A filter membrane is laid on the square notch. A filter feeding chamber and a washing feeding chamber are respectively provided on both sides of the feeding chamber. The filter feeding chamber or the washing feeding chamber corresponds to the position of the square notch. A filter hammer is provided in the filter feeding chamber to hammer the filter membrane. A washing scraper is provided in the washing feeding chamber to scrape the filter membrane. The filter hammer and the washing scraper prevent the filter membrane from clogging when the mixed solution is filtered and washed. The filter hammer and the washing scraper both include a support assembly. The support assembly includes a cylinder installed inside the feeding hopper, a support horizontal plate installed on the telescopic end of the cylinder, and support vertical plates installed at equal intervals on the support horizontal plate. A top extension column is distributed on both sides of the support horizontal plate. One section of the top extension column is connected to the support horizontal plate through a guide telescopic rod, and the other end of the top extension column is slidably connected to the support horizontal plate through a guide column. The filter hammer also includes multiple hammer components installed on the support horizontal plate inside the filter discharge chamber, and one hammer component is distributed between every two support vertical plates. The hammer component includes hammer connecting plates symmetrically installed on both sides of the support horizontal plate inside the filter discharge chamber. Each hammer connecting plate is slidably connected to a hammer connecting rod. The top of the two hammer connecting rods is jointly installed with a hammer plate. The bottom of the hammer connecting rod is installed with a hammer guide block. A hammer spring is sleeved on the outer side of the upper end of the hammer connecting rod and between the hammer connecting plate and the hammer plate. A mating block is installed on the top extension column corresponding to the position of the hammer guide block. The washing scraper also includes multiple scraping components installed between two adjacent support vertical plates in the washing discharge chamber. Each scraping component includes a support guide rod installed between two adjacent support vertical plates in the washing discharge chamber. A scraping vertical plate is slidably connected to the outside of the support guide rod. A scraper is mounted on the top of the scraping vertical plate via a rotating shaft. A return spring is connected between one side of the scraping vertical plate and the corresponding support vertical plate. A toggle rod is installed at both ends of the scraping vertical plate. A push block is provided at the position of the top extension column corresponding to the lower end of the toggle rod.

2. The method for preparing cobalt-nickel-supported graphene microwave absorbing material according to claim 1, characterized in that, The outer surface of the filter membrane is provided with a positioning slot, and the bottom of the filter cavity is slidably provided with a post corresponding to the positioning slot of the filter membrane. The side of the post corresponding to the side wall of the filter cavity is connected to the side wall of the filter cavity through an elastic element.

3. The method for preparing cobalt-nickel-supported graphene microwave absorbing material according to claim 2, characterized in that, The filter chamber is equipped with a pressing component that presses the filter membrane down to make it adhere tightly to the bottom of the filter chamber.

4. The method for preparing cobalt-nickel-supported graphene microwave absorbing material according to claim 3, characterized in that, The pressing assembly includes a pressing frame disposed within the filter chamber and located within the structure formed by the insert post. The size of the pressing frame is larger than the size of the square notch. Both ends of the pressing frame are connected to L-shaped brackets, and the top of each L-shaped bracket is connected to a pressing elastic rod. A support plate is installed on the side wall of the filter chamber, and the upper end of the pressing elastic rod is installed at the bottom of the support plate.

5. The method for preparing cobalt-nickel-supported graphene microwave absorbing material according to claim 1, characterized in that, The pressurization chamber and the unloading chamber are provided with an annular sliding groove and an annular slider that rotate and cooperate with each other. The bottom of the pressurization chamber is provided with a locking slot, and the top of the unloading chamber is provided with a locking block that slides at the position corresponding to the locking slot.

6. The method for preparing cobalt-nickel-supported graphene microwave absorbing material according to claim 1, characterized in that, The top of the hammer plate is uniformly provided with hammer blocks of frustum-shaped structure, and multiple mating blocks are provided. The positions of the mating blocks and the top extension column are all parallelogram structures.

7. The method for preparing cobalt-nickel-supported graphene microwave absorbing material according to claim 1, characterized in that, The scraper has a wave-shaped protrusion on its top, and a friction plate is distributed on both sides of the rotating shaft. The friction plate is installed between two adjacent support vertical plates in the washing and feeding chamber. The two friction plates have intersecting friction blocks on their opposite sides. When the rotating shaft contacts the friction block, the friction block drives the rotating shaft to rotate.

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