CN112250118A - Preparation method of composite material modified graphene, product and application thereof - Google Patents

Preparation method of composite material modified graphene, product and application thereof Download PDF

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CN112250118A
CN112250118A CN202011112372.5A CN202011112372A CN112250118A CN 112250118 A CN112250118 A CN 112250118A CN 202011112372 A CN202011112372 A CN 202011112372A CN 112250118 A CN112250118 A CN 112250118A
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composite material
modified graphene
roasting
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graphene
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CN112250118B (en
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崔大祥
葛美英
李梦飞
刘鹏飞
张芳
卢玉英
王亚坤
张放为
阳靖峰
焦靖华
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Shanghai National Engineering Research Center for Nanotechnology Co Ltd
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    • C01G49/00Compounds of iron
    • C01G49/02Oxides; Hydroxides
    • C01G49/06Ferric oxide [Fe2O3]
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Abstract

The invention discloses a preparation method of composite material modified graphene, and a product and application thereof2O3/g‑C3N4And a layer of Fe-MOF structure is grown on the surface of the composite material, and then the composite material is roasted in an inert gas atmosphere to obtain alpha-Fe2O3/g‑C3N4Modified graphene composite structures. The preparation process is relatively simple, easy to operate and capable of realizing batch production. The material prepared by the method can be used for gasThe material is a body detection sensitive material, a lithium ion battery cathode material, a gas catalytic material, a photocatalytic material, a fuel cell catalyst and the like.

Description

Preparation method of composite material modified graphene, product and application thereof
Technical Field
The invention relates to a method for modifying graphene by using a composite material, in particular to alpha-Fe2O3/g-C3N4A preparation method of modified graphene, and a product and application thereof.
Background
Due to the unique structure, the graphene has very wide application value in various fields, such as fuel cells, gas detection, wearable equipment and the like. However, when the pure graphene material is used for gas detection, the catalytic reaction with the gas is difficult to perform due to fewer active sites, and the application of the graphene material in the field of gas detection is limited.
In the field of gas detection and gas management, alpha-Fe2O3Has better performance as a valence-variable metal oxide, but the poor conductivity of the metal oxide causes the performance to be difficult to fully exert, and the valence-variable metal oxide is mixed with g-C3N4And the graphene is compounded, so that the gas sensitive material for room temperature is expected to be developed.
The invention provides a simple method for realizing alpha-Fe2O3/g-C3N4The method for modifying the graphene has the advantages of simple preparation process and low preparation cost, and has great value for further promoting the practical application of the graphene.
Disclosure of Invention
The invention aims to provide a preparation method of composite material modified graphene.
Yet another object of the present invention is to: the composite material modified graphene product prepared by the method is provided.
Yet another object of the present invention is to: provides an application of the product.
The purpose of the invention is realized by the following scheme: preparation method of composite material modified graphene, wherein the composite material is alpha-Fe2O3/g-C3N4Uniformly mixing urea, ferric salt and graphene, and roasting to obtain alpha-Fe2O3/g-C3N4And a layer of Fe-MOF structure is grown on the surface of the composite material, and finally, the composite material is roasted in an inert gas atmosphere to obtain alpha-Fe2O3/g-C3N4A modified graphene composite structure comprising the steps of:
the method comprises the following steps: grinding and mixing 20g of urea and 2-5 mmol of ferric salt, adding into 20g of deionized water, and grinding for 20-30 min; placing 5-10 g of graphene in a mortar, continuously grinding for 20-30 min, and freeze-drying the obtained slurry at-65 ℃ to obtain powder A;
step two: placing the powder A in a crucible with a cover, and roasting in a muffle furnace to obtain a sample B;
step three: taking 0.2-0.3 mmol of Fe (NO)3)3•9H2Placing O, 0.1-0.15 mmol of 2, 5-dihydroxy-1, 4-phthalic acid, 3-5 mL of dimethylformamide, 0.1g of isopropanol and 0.1g of deionized water in a beaker, stirring for 2-3 h, then adding the sample B obtained in the second step, stirring for 1-2 h, reacting for 3-5 h by adopting a microwave radiation heating method, after the reaction is finished, carrying out centrifugal precipitation, and freeze-drying the obtained precipitate at-65 ℃ to obtain a sample C;
step four: roasting the sample C obtained in the third step in an inert gas atmosphere to obtain alpha-Fe2O3/g-C3N4Modifying graphene.
Wherein in the step one, the ferric salt is FeSO4•9H2O and FeCl2·4H2At least one of O.
In the second step, the roasting atmosphere is air, the temperature is kept at 250-300 ℃ for 2-3 h, 350-400 ℃ for 1-2 h and 500-600 ℃ for 2h, and the temperature rise speed is 1-5 ℃/min.
In the third step, the roasting gas atmosphere is argon or nitrogen, the roasting temperature is 550-650 ℃, the time is 2-3 h, and the temperature rising speed is 1-5 ℃/min. High purity argon or high purity nitrogen is preferred.
The invention also provides the composite material modified graphene prepared by any one of the methods.
The invention also provides application of the composite material modified graphene in a chlorobenzene gas detection sensitive material.
The preparation process is relatively simple, easy to operate and capable of realizing batch production. The material prepared by the method can be used in the fields of gas detection sensitive materials, lithium ion battery cathode materials, gas catalytic materials, photocatalytic materials, fuel cell catalysts and the like.
Drawings
FIG. 1 shows α -Fe according to the present invention2O3/g-C3N4The data graph of the modified graphene for detecting chlorobenzene gases with different concentrations shows that the material has excellent response characteristics to chlorobenzene with different concentrations.
Detailed Description
Example 1:
composite material modified graphene, wherein the composite material is alpha-Fe2O3/g-C3N4The method is characterized in that urea, ferric salt and graphene are uniformly mixed and roasted to obtain alpha-Fe2O3/g-C3N4And a layer of Fe-MOF structure is grown on the surface of the composite material, and finally, the composite material is roasted in an inert gas atmosphere to obtain alpha-Fe2O3/g-C3N4The modified graphene composite structure is prepared by the following steps:
the method comprises the following steps: 20g of urea and 2mmol of ferric salt FeSO are taken4•9H2Grinding and mixing O, adding into 20g of deionized water, and grinding for 20 min; placing 5g of graphene in a mortar, continuously grinding for 30min, and freeze-drying the obtained slurry at-65 ℃ to obtain powder A;
step two: placing the powder A in a crucible with a cover, roasting in a muffle furnace, and keeping the roasting temperature at 250 ℃ for 2h, 350 ℃ for 1h and 550 ℃ for 2h at the heating speed of 2 ℃/min to obtain a sample B;
step three: 0.2mmol of Fe (NO) was taken3)3•9H2Placing O, 0.1mmol of 2, 5-dihydroxy-1, 4-phthalic acid, 3mL of dimethylformamide, 0.1g of isopropanol and 0.1g of deionized water in a beaker, stirring for 3 hours, then adding the sample B obtained in the step two, stirring for 2 hours, reacting for 5 hours by adopting a microwave radiation heating method, after the reaction is finished, carrying out centrifugal precipitation, and carrying out freeze drying on the obtained precipitate at-65 ℃ to obtain a sample C;
step four: roasting the sample C in an inert gas high-purity argon atmosphere at the roasting temperature of 550 ℃, the roasting time of 3h and the heating speed of 1 ℃/min to obtain alpha-Fe2O3/g-C3N4Modifying graphene.
The powder prepared by the embodiment is dispersedly coated on a six-pin ceramic tube gas-sensitive test element, the test material has the response to chlorobenzene gas, the optimal response temperature to chlorobenzene is 180 ℃, the lowest response limit is 10ppb, and the sensitivity is 5.2. See figure 1 for details.
Example 2:
the composite material modified graphene is prepared by the following steps in the same way as the steps in the embodiment:
the method comprises the following steps: 20g of urea and 5mmol of ferric salt FeSO are taken4•9H2Grinding and mixing O, adding into 20g of deionized water, and grinding for 30 min; placing 5g of graphene in a mortar, continuously grinding for 30min, and freeze-drying the obtained slurry at-65 ℃ to obtain powder A;
step two: placing the powder A in a crucible with a cover, roasting in a muffle furnace, and keeping the roasting temperature at 300 ℃ for 2h, 350 ℃ for 1h and 550 ℃ for 2h at the heating speed of 2 ℃/min to obtain a sample B;
step three: 0.3mmol of Fe (NO) was taken3)3•9H2O, 0.15mmol of 2, 5-dihydroxy-1, 4-phthalic acid, 3mL of dimethylformamide, 0.1g of isopropanol and 0.1g of deionized water are placed in a beaker and stirred for 3 hours, then a sample B is added and stirred for 2 hours, a microwave radiation heating method is adopted for reaction for 5 hours, after the reaction is finished, centrifugal precipitation is carried out, and the obtained precipitate is subjected to centrifugal precipitationFreeze-drying at-65 ℃ to obtain a sample C;
step four: roasting the sample C in an inert gas high-purity argon atmosphere at the roasting temperature of 550 ℃, the roasting time of 3h and the heating speed of 1 ℃/min to obtain alpha-Fe2O3/g-C3N4Modifying graphene.
The powder prepared by the embodiment is dispersedly coated on a six-pin ceramic tube gas-sensitive test element, the test material has the response to chlorobenzene gas, the optimal response temperature to chlorobenzene is 180 ℃, the lowest response limit is 10ppb, and the sensitivity is 8.4. See figure 1 for details.
Example 3:
the composite material modified graphene is prepared by the following steps in the same way as the steps in the embodiment:
the method comprises the following steps: 20g of urea and 2mmol of ferric salt FeSO are taken4•9H2Grinding and mixing O, adding into 20g of deionized water, and grinding for 30 min; placing 10g of graphene in a mortar, continuously grinding for 30min, and freeze-drying the obtained slurry at-65 ℃ to obtain powder A;
step two: placing the powder A in a crucible with a cover, roasting in a muffle furnace, and keeping the roasting temperature at 300 ℃ for 2h, 350 ℃ for 1h and 550 ℃ for 2h at the heating speed of 5 ℃/min to obtain a sample B;
step three: 0.2mmol of Fe (NO) was taken3)3•9H2Placing O, 0.15mmol of 2, 5-dihydroxy-1, 4-phthalic acid, 3mL of dimethylformamide, 0.1g of isopropanol and 0.1g of deionized water in a beaker, stirring for 3 hours, then adding the sample B, stirring for 2 hours, reacting for 3 hours by adopting a microwave radiation heating method, after the reaction is finished, carrying out centrifugal precipitation, and carrying out freeze drying on the obtained precipitate at-65 ℃ to obtain a sample C;
step four: roasting the sample C in an inert gas high-purity argon atmosphere at the roasting temperature of 650 ℃ for 2h at the heating speed of 5 ℃/min to obtain alpha-Fe2O3/g-C3N4Modifying graphene.
The powder prepared by the embodiment is dispersedly coated on a six-pin ceramic tube gas-sensitive test element, the test material has the response to chlorobenzene gas, the optimal response temperature to chlorobenzene is 180 ℃, the lowest response limit is 10ppb, and the sensitivity is 3.24. See figure 1 for details.
The embodiments described above are described to facilitate an understanding and appreciation of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the embodiments described herein, and those skilled in the art should make improvements and modifications to the present invention based on the disclosure of the present invention within the protection scope of the present invention.

Claims (6)

1. Preparation method of composite material modified graphene, wherein the composite material is alpha-Fe2O3/g-C3N4The method is characterized in that urea, ferric salt and graphene are uniformly mixed and roasted to obtain alpha-Fe2O3/g-C3N4And a layer of Fe-MOF structure is grown on the surface of the composite material, and finally, the composite material is roasted in an inert gas atmosphere to obtain alpha-Fe2O3/g-C3N4A modified graphene composite structure comprising the steps of:
the method comprises the following steps: grinding and mixing 20g of urea and 2-5 mmol of ferric salt, adding into 20g of deionized water, and grinding for 20-30 min; placing 5-10 g of graphene in a mortar, continuously grinding for 20-30 min, and freeze-drying the obtained slurry at-65 ℃ to obtain powder A;
step two: placing the powder A in a crucible with a cover, and roasting in a muffle furnace to obtain a sample B;
step three: taking 0.2-0.3 mmol of Fe (NO)3)3•9H2Placing O, 0.1-0.15 mmol of 2, 5-dihydroxy-1, 4-phthalic acid, 3-5 mL of dimethylformamide, 0.1g of isopropanol and 0.1g of deionized water in a beaker, stirring for 2-3 h, then adding the sample B obtained in the second step, stirring for 1-2 h, reacting for 3-5 h by adopting a microwave radiation heating method, after the reaction is finished, carrying out centrifugal precipitation, and freeze-drying the obtained precipitate at-65 ℃ to obtain a sample C;
step four: placing the sample C in an inert gas atmosphereMedium roasting to obtain alpha-Fe2O3/g-C3N4Modifying graphene.
2. The preparation method of the composite material modified graphene according to claim 1, characterized by comprising the following steps: in the first step, the ferric salt is FeSO4•9H2O and FeCl2·4H2At least one of O.
3. The preparation method of the composite material modified graphene according to claim 1, characterized by comprising the following steps: in the second step, the roasting atmosphere is air, the temperature is kept at 250-300 ℃ for 2-3 h, 350-400 ℃ for 1-2 h and 500-600 ℃ for 2h, and the temperature rise speed is 1-5 ℃/min.
4. The preparation method of the composite material modified graphene according to claim 1, characterized by comprising the following steps: in the third step, the roasting gas atmosphere is argon or nitrogen, the roasting temperature is 550-650 ℃, the time is 2-3 h, and the temperature rising speed is 1-5 ℃/min.
5. Composite material modified graphene, characterized in that it is prepared according to the method of any one of claims 1 to 4.
6. The application of the composite material modified graphene according to claim 5 in a chlorobenzene gas detection sensitive material.
CN202011112372.5A 2020-10-16 2020-10-16 Preparation method of composite material modified graphene, product and application thereof Active CN112250118B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113866237A (en) * 2021-09-16 2021-12-31 湖南大学 Flexible photoelectrochemical aptamer sensor and preparation method and application thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102603014A (en) * 2011-10-08 2012-07-25 北京中科微纳物联网技术股份有限公司 Environment-friendly and efficient method for preparing iron sesquioxide/graphene composite material
CN108246331A (en) * 2018-01-16 2018-07-06 东北师范大学 ZnS micro-composites of graphene carbonization nitrogen quantity point modification and its preparation method and application
US20200016585A1 (en) * 2018-07-12 2020-01-16 Soochow University Visible-light response hybrid aerogel and preparation method and application thereof in waste gas processing
CN111740105A (en) * 2020-07-06 2020-10-02 邓新峰 S, N co-doped porous graphene modified copper phosphide lithium ion battery negative electrode material

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102603014A (en) * 2011-10-08 2012-07-25 北京中科微纳物联网技术股份有限公司 Environment-friendly and efficient method for preparing iron sesquioxide/graphene composite material
CN108246331A (en) * 2018-01-16 2018-07-06 东北师范大学 ZnS micro-composites of graphene carbonization nitrogen quantity point modification and its preparation method and application
US20200016585A1 (en) * 2018-07-12 2020-01-16 Soochow University Visible-light response hybrid aerogel and preparation method and application thereof in waste gas processing
CN111740105A (en) * 2020-07-06 2020-10-02 邓新峰 S, N co-doped porous graphene modified copper phosphide lithium ion battery negative electrode material

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113866237A (en) * 2021-09-16 2021-12-31 湖南大学 Flexible photoelectrochemical aptamer sensor and preparation method and application thereof
CN113866237B (en) * 2021-09-16 2023-09-12 湖南大学 Flexible photoelectrochemical aptamer sensor and preparation method and application thereof

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