CN110256732B - Ferroferric oxide-graphene-cellulose conductive composite aerogel applied to field of electromagnetic shielding and preparation method thereof - Google Patents
Ferroferric oxide-graphene-cellulose conductive composite aerogel applied to field of electromagnetic shielding and preparation method thereof Download PDFInfo
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Abstract
The invention discloses ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding and a preparation method thereof. The preparation method comprises the following steps: dissolving cellulose in an aqueous solution of sodium hydroxide/urea, mixing an aqueous solution of graphene oxide with a cellulose solution, casting to form a film to obtain hydrogel, performing in-situ reduction by using a reducing agent, sequentially soaking the hydrogel in an aqueous solution of ferric chloride and ferrous chloride and an aqueous alkali solution to generate ferroferric oxide in situ, washing the ferroferric oxide-graphene-cellulose conductive composite aerogel for the field of electromagnetic shielding by using deionized water for multiple times, and performing freeze drying to obtain the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding. The aerogel provided by the invention has a good electromagnetic shielding effect. The preparation method provided by the invention has the advantages of simple process, convenient operation, no environmental pollution and the like. The composite aerogel provided by the invention can be applied to the fields of electromagnetic shielding materials and the like.
Description
Technical Field
The invention belongs to the field of electromagnetic shielding, and particularly relates to ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding and a preparation method thereof.
With the development of modern communication equipment, electronic equipment and radio communication are widely used in our daily life. At the same time. The harm of electromagnetic radiation is also getting more and more serious, which not only interferes the normal operation of electronic equipment, but also causes harm to human health. Therefore, the use of electromagnetic shielding materials to eliminate the hazards of such electromagnetic radiation is highly desirable. Electromagnetic shielding is currently used in the military and civilian fields, such as wireless devices, aircraft manufacturing, electronic equipment, and the like. Therefore, the requirements and performances of electromagnetic shielding materials are higher and higher. However, the conventional electromagnetic shielding materials are basically based on metals, and have the disadvantages of being disadvantageous to processing, being easily corroded, having high density of shielding materials, and the like, and therefore, the problem to be solved is urgently needed to search for an electromagnetic shielding material which is light in weight, stable and has high electromagnetic shielding performance. Meanwhile, with the increasing problems of white pollution and plastic recycling, recyclable and biodegradable natural polymers are receiving more and more attention. Cellulose has wide application prospect as the most abundant natural high polymer. Because it is cheap and biodegradable, it can be used to prepare packing film and functional material to solve the problem of environmental pollution. In addition, the cellulose aerogel material has good processability, so that the matrix of the electromagnetic shielding material can play a role together with ferroferric oxide and graphene to improve the electromagnetic shielding performance of the material. The aerogel material has the advantages of good magnetic property and conductivity, light weight and the like, has excellent electromagnetic shielding property, has the processability and mechanical property of a high polymer material, and can be widely applied to multiple fields of electromagnetic shielding and the like.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention aims to provide ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding and a preparation method thereof.
The purpose of the invention is realized by at least one of the following technical solutions.
The invention provides a preparation method of ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding, which comprises the following steps: taking cellulose as a base material, compounding graphene oxide, reducing, and then generating ferroferric oxide in situ to prepare the composite aerogel material for the electromagnetic shielding field; the process for preparing the composite aerogel has the advantages of simple process, convenient operation, no pollution to the environment and the like. The composite conductive aerogel provided by the invention can be applied to the fields of electromagnetic shielding materials and the like.
The invention provides a preparation method of ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding, which comprises the following steps:
(1) adding sodium hydroxide and urea into water, uniformly mixing to obtain a sodium hydroxide/urea mixed aqueous solution, and dispersing graphene oxide in the water to obtain a graphene oxide aqueous solution;
(2) precooling the mixed aqueous solution of sodium hydroxide/urea in the step (1), then adding cellulose, and uniformly stirring to obtain a cellulose solution; adding the aqueous solution of the graphene oxide obtained in the step (1) into a cellulose solution, and uniformly mixing to obtain a mixed solution; casting the mixed solution into a film, then carrying out coagulation bath treatment in a dilute sulfuric acid solution, carrying out coagulation forming to obtain hydrogel, taking out the hydrogel, and washing the hydrogel in deionized water for multiple times;
(3) soaking the hydrogel washed in the step (2) in a reducing agent solution for reduction treatment (in-situ reduction) to obtain graphene-cellulose composite hydrogel, taking out the graphene-cellulose composite hydrogel, and washing the hydrogel in deionized water for multiple times;
(4) adding ferric chloride and ferrous chloride into water, uniformly mixing to obtain a mixed aqueous solution of ferric chloride and ferrous chloride, sequentially soaking the graphene-cellulose composite hydrogel washed in the step (3) in the mixed aqueous solution of ferric chloride and ferrous chloride and an alkaline solution to obtain ferroferric oxide-graphene-cellulose composite hydrogel, washing with deionized water for multiple times, and freeze-drying to obtain the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding.
Further, the mass ratio of the sodium hydroxide to the urea in the step (1) is 6: 14-8: 10; the mass ratio of the urea to the water is 10: 82-14: 80; the mass percentage concentration of the aqueous solution of the graphene oxide is 0.2-2%.
Preferably, the pre-cooling temperature in the step (2) is-12 to-20 ℃, and the pre-cooling time is 1 to 2 hours; preferably, the stirring time for uniformly stirring in the step (2) (the stirring time for dissolving the cellulose) is 5-10 minutes.
Further, the mass of the cellulose in the step (2) is 2-8% of that of the mixed aqueous solution of sodium hydroxide and urea; the mass ratio of the graphene oxide in the step (1) to the cellulose in the step (2) is 2: 98-8: 92.
further, the volume of the aqueous solution of graphene oxide in the step (2) is 10-30% of the volume of the cellulose solution.
Further, the mass percent concentration of the dilute sulfuric acid solution in the step (2) is 4% -6%, and the treatment time of the coagulating bath is 5-10 minutes.
Further, the reducing agent solution in the step (3) comprises an aqueous solution of vitamin C, and the concentration of the aqueous solution of vitamin C is 30-50 g/L; the temperature of the reduction treatment is 90-95 ℃, and the time of the reduction treatment is 1-2 hours.
Further, the molar ratio of the ferric chloride to the ferrous chloride in the step (4) is 1.6: 1.4-2.4: 0.6; the mass volume ratio of the ferric chloride to the water is 5-10: 1 g/L.
Further, soaking the washed graphene-cellulose composite hydrogel in the mixed aqueous solution of ferric chloride and ferrous chloride for 30-60 minutes; the alkaline solution in the step (4) comprises a sodium hydroxide solution, the mass percentage concentration is 5% -10%, and the time for soaking the washed graphene-cellulose composite hydrogel in the alkaline solution is 5-10 minutes.
Preferably, the freeze-drying time in step (3) is 20 to 24 hours.
The invention provides ferroferric oxide-graphene-cellulose conductive composite aerogel prepared by the preparation method and applied to the field of electromagnetic shielding.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) in the preparation method provided by the invention, the used raw material cellulose is the most extensive natural high polymer material in nature, has wide sources and low price, and belongs to an environment-friendly material; the preparation method has the advantages of simple process, low requirement on equipment, contribution to large-scale production, simplicity and convenience in operation and the like.
(2) The cellulose-based aerogel prepared by the method disclosed by the invention is uniform in foam pores, and simultaneously, the graphene and ferroferric oxide play a synergistic effect, so that the electromagnetic shielding effect of the aerogel material can be improved together.
Detailed Description
The following examples are presented to further illustrate the practice of the invention, but the practice and protection of the invention is not limited thereto. It is noted that the processes described below, if not specifically described in detail, are all realizable or understandable by those skilled in the art with reference to the prior art. The reagents or apparatus used are not indicated to the manufacturer, and are considered to be conventional products available by commercial purchase.
Example 1
The preparation method of the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding, provided by the embodiment 1, comprises the following steps:
(1) adding 20g of sodium hydroxide and urea into water, and uniformly mixing to obtain a sodium hydroxide/urea mixed aqueous solution, wherein in the sodium hydroxide/urea mixed aqueous solution, the mass percent concentration of the sodium hydroxide is 7 wt%, and the mass percent concentration of the urea is 12 wt%; dispersing 0.08 g of graphene oxide in 20 ml of water to obtain an aqueous solution of the graphene oxide;
(2) pre-cooling the mixed aqueous solution of sodium hydroxide/urea in the step (1), wherein the pre-cooling temperature is-12 ℃, and the pre-cooling time is 1 hour; adding 3.92 g of cellulose into 96 g of sodium hydroxide/urea mixed aqueous solution, stirring for 5 minutes, uniformly stirring to obtain a cellulose solution, adding 20 ml of graphene oxide aqueous solution into 100 ml of cellulose solution, and uniformly mixing to obtain a mixed solution; casting the mixed solution on a glass plate to form a film, then carrying out coagulation bath treatment in a dilute sulfuric acid solution (the concentration of the dilute sulfuric acid solution is 4 wt%), wherein the coagulation bath treatment time is 5 minutes, so as to obtain hydrogel, and washing the hydrogel by using deionized water;
(3) soaking the hydrogel washed in the step (2) in 500 ml of reducing agent solution (vitamin C aqueous solution with the concentration of 30 g/L) for reduction treatment, wherein the temperature of the reduction treatment is 95 ℃, the time of the reduction treatment is 1 hour, so as to obtain graphene-cellulose composite hydrogel, and washing the graphene-cellulose composite hydrogel with deionized water;
(4) adding 8mmol of ferric chloride and 4mmol of ferrous chloride into 200 ml of water, and uniformly mixing to obtain a mixed aqueous solution of the ferric chloride and the ferrous chloride; soaking the graphene-cellulose composite hydrogel washed in the step (3) in the mixed aqueous solution of ferric chloride and ferrous chloride for 30 minutes; and then soaking in 100 ml of alkaline solution (5 wt% sodium hydroxide solution) for 5 minutes to obtain ferroferric oxide-graphene-cellulose composite hydrogel, washing with deionized water for multiple times, and freeze-drying for 1 hour to obtain the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding. The ratio of the graphene oxide to the cellulose in the step (1) is 2: 98.
(5) through the steps, the thickness of the prepared ferroferric oxide-graphene-cellulose conductive composite aerogel is 2 mm, and the electromagnetic shielding performance is 44 dB. The light aerogel material is only added with a small amount of graphene, and the electromagnetic shielding performance exceeds the application requirement (20dB) of the electromagnetic shielding material.
Example 2
The preparation method of the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding, provided by embodiment 2, comprises the following steps:
(1) adding 20g of sodium hydroxide and urea into water, and uniformly mixing to obtain a sodium hydroxide/urea mixed aqueous solution, wherein in the sodium hydroxide/urea mixed aqueous solution, the mass percent concentration of the sodium hydroxide is 6 wt%, and the mass percent concentration of the urea is 14 wt%; dispersing 0.16 g of graphene oxide in 20 ml of water to obtain an aqueous solution of the graphene oxide;
(2) pre-cooling the mixed aqueous solution of sodium hydroxide and urea in the step (1), wherein the pre-cooling temperature is-18 ℃, and the pre-cooling time is 1.5 hours; adding 3.84 g of cellulose into 96 g of sodium hydroxide/urea mixed aqueous solution, stirring for 5 minutes, uniformly stirring to obtain a cellulose solution, adding 10 ml of graphene oxide aqueous solution into 100 ml of cellulose solution, and uniformly mixing to obtain a mixed solution; casting the mixed solution on a glass plate to form a film, then carrying out coagulation bath treatment in a dilute sulfuric acid solution (the concentration of the dilute sulfuric acid solution is 4 wt%), wherein the coagulation bath treatment time is 7 minutes, so as to obtain hydrogel, and washing the hydrogel by using deionized water;
(3) soaking the hydrogel washed in the step (2) in 500 ml of reducing agent solution (aqueous solution of vitamin C with the concentration of 40 g/L) for reduction treatment at the temperature of 95 ℃ for 1.5 hours to obtain graphene-cellulose composite hydrogel, and washing the graphene-cellulose composite hydrogel with deionized water;
(4) adding 8mmol of ferric chloride and 4mmol of ferrous chloride into 200 ml of water, and uniformly mixing to obtain a mixed aqueous solution of the ferric chloride and the ferrous chloride; soaking the graphene-cellulose composite hydrogel washed in the step (3) in the mixed aqueous solution of ferric chloride and ferrous chloride for 1 hour; and then soaking in 100 ml of alkaline solution (5 wt% sodium hydroxide solution) for 5 minutes to obtain ferroferric oxide-graphene-cellulose composite hydrogel, washing with deionized water for multiple times, and freeze-drying for 22 hours to obtain the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding. The ratio of the graphene oxide to the cellulose in the step (1) is 4: 96.
(5) through the steps, the thickness of the prepared ferroferric oxide-graphene-cellulose conductive composite aerogel is 2 mm, and the electromagnetic shielding performance is 50 dB. The light aerogel material is only added with a small amount of graphene, and the electromagnetic shielding performance exceeds the application requirement (20dB) of the electromagnetic shielding material. Meanwhile, with the increase of the content of graphene, the propagation path of electromagnetic waves in the aerogel material is increased, so that higher electromagnetic shielding performance is obtained.
Example 3
The preparation method of the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding, provided by embodiment 3, includes the following steps:
(1) adding 20g of sodium hydroxide and urea into water, and uniformly mixing to obtain a sodium hydroxide/urea mixed aqueous solution, wherein in the sodium hydroxide/urea mixed aqueous solution, the mass percent concentration of the sodium hydroxide is 8 wt%, and the mass percent concentration of the urea is 10 wt%; dispersing 0.24 g of graphene oxide in 20 ml of water to obtain an aqueous solution of the graphene oxide;
(2) pre-cooling the mixed aqueous solution of sodium hydroxide/urea in the step (1), wherein the pre-cooling temperature is-20 ℃, and the pre-cooling time is 1 hour; adding 3.76 g of cellulose into 96 g of sodium hydroxide/urea mixed aqueous solution, stirring for 5 minutes, uniformly stirring to obtain a cellulose solution, adding 30 ml of graphene oxide aqueous solution into 100 ml of cellulose solution, and uniformly mixing to obtain a mixed solution; casting the mixed solution on a glass plate to form a film, then carrying out coagulation bath treatment in a dilute sulfuric acid solution (the concentration of the dilute sulfuric acid solution is 6 wt%), wherein the coagulation bath treatment time is 5 minutes, so as to obtain hydrogel, and washing the hydrogel with deionized water;
(3) soaking the hydrogel washed in the step (2) in 500 ml of reducing agent solution (vitamin C aqueous solution with the concentration of 50 g/L) for reduction treatment, wherein the temperature of the reduction treatment is 90 ℃, and the time of the reduction treatment is 2 hours, so as to obtain graphene-cellulose composite hydrogel, and washing the graphene-cellulose composite hydrogel by using deionized water;
(4) adding 8mmol of ferric chloride and 4mmol of ferrous chloride into 200 ml of water, and uniformly mixing to obtain a mixed aqueous solution of the ferric chloride and the ferrous chloride; soaking the graphene-cellulose composite hydrogel washed in the step (3) in the mixed aqueous solution of ferric chloride and ferrous chloride for 1 hour; and then soaking in 100 ml of alkaline solution (10 wt% sodium hydroxide solution) for 5 minutes to obtain ferroferric oxide-graphene-cellulose composite hydrogel, washing with deionized water for multiple times, and freeze-drying for 24 hours to obtain the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding. The ratio of the graphene oxide to the cellulose in the step (1) is 6: 94.
(5) through the steps, the thickness of the prepared ferroferric oxide-graphene-cellulose conductive composite aerogel is 2 mm, and the electromagnetic shielding performance is 62 dB. The light aerogel material is only added with a small amount of graphene, and the electromagnetic shielding performance is far higher than the application requirement (20dB) of the electromagnetic shielding material. Meanwhile, with the increase of the content of graphene, the propagation path of electromagnetic waves in the aerogel material is increased, so that higher electromagnetic shielding performance is obtained.
Example 4
The preparation method of the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding, provided by embodiment 4, includes the following steps:
(1) adding 20g of sodium hydroxide and urea into water, and uniformly mixing to obtain a sodium hydroxide/urea mixed aqueous solution, wherein in the sodium hydroxide/urea mixed aqueous solution, the mass percent concentration of the sodium hydroxide is 7 wt%, and the mass percent concentration of the urea is 12 wt%; dispersing 0.32 g of graphene oxide in 20 ml of water to obtain an aqueous solution of the graphene oxide;
(2) pre-cooling the mixed aqueous solution of sodium hydroxide/urea in the step (1), wherein the pre-cooling temperature is-12 ℃, and the pre-cooling time is 1 hour; adding 3.68 g of cellulose into 96 g of sodium hydroxide/urea mixed aqueous solution, stirring for 5 minutes, uniformly stirring to obtain a cellulose solution, adding 20 ml of graphene oxide aqueous solution into 100 ml of cellulose solution, and uniformly mixing to obtain a mixed solution; casting the mixed solution on a glass plate to form a film, then carrying out coagulation bath treatment in a dilute sulfuric acid solution (the concentration of the dilute sulfuric acid solution is 5 wt%), wherein the coagulation bath treatment time is 5 minutes, so as to obtain hydrogel, and washing the hydrogel by using deionized water;
(3) soaking the hydrogel washed in the step (2) in 500 ml of reducing agent solution (vitamin C aqueous solution with the concentration of 30 g/L) for reduction treatment, wherein the temperature of the reduction treatment is 95 ℃, the time of the reduction treatment is 1 hour, so as to obtain graphene-cellulose composite hydrogel, and washing the graphene-cellulose composite hydrogel with deionized water;
(4) adding 8mmol of ferric chloride and 4mmol of ferrous chloride into 200 ml of water, and uniformly mixing to obtain a mixed aqueous solution of the ferric chloride and the ferrous chloride; soaking the graphene-cellulose composite hydrogel washed in the step (3) in the mixed aqueous solution of ferric chloride and ferrous chloride for 1 hour; and then soaking in 100 ml of alkaline solution (5 wt% sodium hydroxide solution) for 5 minutes to obtain ferroferric oxide-graphene-cellulose composite hydrogel, washing with deionized water for multiple times, and freeze-drying for 1 hour to obtain the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding. The ratio of the graphene oxide to the cellulose in the step (1) is 8: 92.
(5) through the steps, the thickness of the prepared ferroferric oxide-graphene-cellulose conductive composite aerogel is 2 mm, and the electromagnetic shielding performance is 74 dB. The light aerogel material is only added with a small amount of graphene, and the electromagnetic shielding performance exceeds the application requirement (20dB) of the electromagnetic shielding material. Meanwhile, with the increase of the content of graphene, the propagation path of electromagnetic waves in the aerogel material is increased, so that higher electromagnetic shielding performance is obtained.
The above examples are only preferred embodiments of the present invention, which are intended to be illustrative and not limiting, and those skilled in the art should understand that they can make various changes, substitutions and alterations without departing from the spirit and scope of the invention.
Claims (7)
1. A preparation method of ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding is characterized by comprising the following steps:
(1) adding sodium hydroxide and urea into water, uniformly mixing to obtain a sodium hydroxide/urea mixed aqueous solution, and dispersing graphene oxide in the water to obtain a graphene oxide aqueous solution; the mass ratio of the sodium hydroxide to the urea is 6: 14-8: 10; the mass ratio of the urea to the water is 10: 82-14: 80; the mass percentage concentration of the aqueous solution of the graphene oxide is 0.2-2%;
(2) precooling the mixed aqueous solution of sodium hydroxide/urea in the step (1), then adding cellulose, and uniformly stirring to obtain a cellulose solution; adding the aqueous solution of the graphene oxide obtained in the step (1) into a cellulose solution, and uniformly mixing to obtain a mixed solution; casting the mixed solution into a film, then carrying out coagulation bath treatment in a dilute sulfuric acid solution to obtain hydrogel, and washing; the pre-cooling temperature is-20 ℃ to-12 ℃, and the pre-cooling time is 1-2 hours; the mass of the cellulose in the step (2) is 2-8% of that of the mixed aqueous solution of sodium hydroxide and urea; the mass ratio of the graphene oxide in the step (1) to the cellulose in the step (2) is 2: 98-8: 92;
(3) soaking the hydrogel washed in the step (2) in a reducing agent solution for reduction treatment to obtain graphene-cellulose composite hydrogel, and washing; the reducing agent solution comprises an aqueous solution of vitamin C, and the concentration of the aqueous solution of vitamin C is 30-50 g/L; the temperature of the reduction treatment is 90-95 ℃, and the time of the reduction treatment is 1-2 hours;
(4) adding ferric chloride and ferrous chloride into water, uniformly mixing to obtain a mixed aqueous solution of the ferric chloride and the ferrous chloride, sequentially soaking the graphene-cellulose composite hydrogel washed in the step (3) in the mixed aqueous solution of the ferric chloride and the ferrous chloride and an alkaline solution to obtain ferroferric oxide-graphene-cellulose composite hydrogel, washing, and freeze-drying to obtain the ferroferric oxide-graphene-cellulose conductive composite aerogel applied to the field of electromagnetic shielding.
2. The preparation method according to claim 1, wherein the volume of the aqueous solution of graphene oxide in the step (2) is 10 to 30% of the volume of the cellulose solution.
3. The preparation method according to claim 1, wherein the dilute sulfuric acid solution in the step (2) has a mass percent concentration of 4-6%, and the coagulation bath treatment time is 5-10 minutes.
4. The preparation method according to claim 1, wherein the molar ratio of the ferric chloride to the ferrous chloride in the step (4) is 1.6: 1.4-2.4: 0.6; the mass volume ratio of the ferric chloride to the water is 5-10: 1 g/L.
5. The preparation method according to claim 1, wherein the graphene-cellulose composite hydrogel in the step (4) is soaked in the mixed aqueous solution of ferric chloride and ferrous chloride for 30 to 60 minutes; the alkaline solution in the step (4) comprises a sodium hydroxide solution, the mass percentage concentration of the alkaline solution is 5% -10%, and the time for soaking the graphene-cellulose composite hydrogel in the alkaline solution is 5-10 minutes.
6. The method according to claim 1, wherein the freeze-drying time in the step (4) is 20 to 24 hours.
7. The ferroferric oxide-graphene-cellulose conductive composite aerogel prepared by the preparation method of any one of claims 1 to 6 and applied to the field of electromagnetic shielding.
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| CN112497860B (en) * | 2020-05-07 | 2023-04-07 | 砾维(新乡)纺织有限公司 | Long-acting flame-retardant anti-piercing anti-radiation composite fabric |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103173189A (en) * | 2013-03-06 | 2013-06-26 | 西北工业大学 | Method for preparing reduced graphene oxide/ferroferric oxide nano-grade wave-absorbing materials |
| CN105802579A (en) * | 2016-04-06 | 2016-07-27 | 华南师范大学 | Nano Fe3O4/graphene composite material with high saturation magnetization and electromagnetic shielding function as well as preparation method of composite material |
| CN108557899A (en) * | 2018-06-15 | 2018-09-21 | 中科广化（重庆）新材料研究院有限公司 | A kind of graphene-supported ferroferric oxide wave absorbing material and preparation method thereof |
| CN109535485A (en) * | 2018-11-29 | 2019-03-29 | 广西科技师范学院 | A kind of preparation method of magnetic cellulose/graphene oxide high-efficiency environment friendly absorption aeroge |
| CN109607509A (en) * | 2019-01-11 | 2019-04-12 | 四川大学 | A kind of preparation method of the full biomass-based carbon aerogels of high electromagnet shield effect |
-
2019
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103173189A (en) * | 2013-03-06 | 2013-06-26 | 西北工业大学 | Method for preparing reduced graphene oxide/ferroferric oxide nano-grade wave-absorbing materials |
| CN105802579A (en) * | 2016-04-06 | 2016-07-27 | 华南师范大学 | Nano Fe3O4/graphene composite material with high saturation magnetization and electromagnetic shielding function as well as preparation method of composite material |
| CN108557899A (en) * | 2018-06-15 | 2018-09-21 | 中科广化（重庆）新材料研究院有限公司 | A kind of graphene-supported ferroferric oxide wave absorbing material and preparation method thereof |
| CN109535485A (en) * | 2018-11-29 | 2019-03-29 | 广西科技师范学院 | A kind of preparation method of magnetic cellulose/graphene oxide high-efficiency environment friendly absorption aeroge |
| CN109607509A (en) * | 2019-01-11 | 2019-04-12 | 四川大学 | A kind of preparation method of the full biomass-based carbon aerogels of high electromagnet shield effect |
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