Graphene preparation method

A graphene and graphite intercalation technology, applied in the technical field of preparation methods, can solve the problems of difficult preparation, long stripping time, high cost, etc., achieve short expansion implementation time, low waste liquid treatment cost, and prevent a small amount of oxidation Effect

Active Publication Date: 2014-07-30
SOUTH CHINA UNIV OF TECH
View PDF2 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the current graphene preparation is still mainly based on reduced graphene oxide (rGO), which has large structural defects, which leads to a significant decrease in the electrical, optical, and thermal properties of graphene. At the same time, using This method is relatively difficult to prepare, high in cost, low in efficiency and pollutes the environment
Chinese patent 201110282370.5 discloses a method for preparing high-quality graphene. The graphene structure defects prepared by the method are small, but when peeling off, when the catalyst such as ferric chloride seeps out a large amount, it will cause hydrogen peroxide to over-catalyze and release heat. Vigorous reaction, hydrogen peroxide at higher temperature will cause partial damage to the graphene layer structure, so that some properties of graphene cannot be improved, and its stripping time is relatively long, which has certain restrictions on industrialization and safety

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Graphene preparation method
  • Graphene preparation method
  • Graphene preparation method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] Put 1g of the second-order graphite intercalation compound with bromine as the intercalation agent in a 300ml beaker, add 50ml of 5wt% sodium borohydride solution, and let it stand for 3 minutes to obtain highly expanded worm graphite floating on the liquid surface. After filtering and washing the worm graphite with dilute sulfuric acid for 3 times, add 1L of ethanol solution (the volume ratio of ethanol to water is 1:4), and oscillate ultrasonically for 3 hours to obtain a graphene dispersion solution. The yield is about 93%, and graphene powder can be obtained after one day of freeze-drying. The number of graphene layers obtained is 2-5 layers, and the conductivity is 3×10 5 S / m.

[0030] Conduct electrical performance comparison experiments under the same conditions

[0031] The same reaction amount of graphene intercalation compound and the same instrument were used for determination. The results show that the electrical performance of the hydrogen peroxide syste...

Embodiment 2

[0033] Put 2g of the first-order graphite intercalation compound with ferric chloride as the intercalation agent in a 500ml beaker, add 80ml of 8wt% sodium borohydride solution, and let it stand for 2 minutes to obtain highly expanded worm graphite floating on the liquid surface. After the worm graphite was filtered and washed with dilute sulfuric acid for 3 times, it was added to 1L of 1wt% PVP ethanol solution, and ultrasonically oscillated for 1 hour to obtain a graphene dispersion solution. A small amount of the upper layer was removed to obtain fully ultrasonically expanded graphite, and the yield was about 76%. %, graphene powder can be obtained after freeze-drying for one day. The number of graphene layers obtained is 1-5 layers, and the conductivity is 3×10 5 S / m.

[0034] Conduct electrical performance comparison experiments under the same conditions

[0035] The same reaction amount of graphene intercalation compound and the same instrument were used for determinat...

Embodiment 3

[0039] Add 1.5g of a first-order graphite intercalation compound using zinc chloride as an intercalation agent to a 500ml beaker, add 60ml of lithium borohydride solution with a concentration of 7wt%, and let it stand for 1min to obtain highly expanded worm graphite floating on the liquid surface . After the worm graphite was filtered and washed with dilute hydrochloric acid for 3 times, it was added to 500ml concentration of 2wt%PVP aqueous solution, and ultrasonically oscillated for 2h to obtain a graphene sheet dispersion solution. The upper layer of insufficient ultrasonically expanded graphite was removed, and the yield was about 84%. Graphene powder can be obtained after freeze-drying for one day. The number of graphene layers obtained is 1-5 layers, and the conductivity is 3×10 5 S / m.

[0040] Conduct electrical performance comparison experiments under the same conditions

[0041] The same reaction amount of graphene intercalation compound and the same instrument wer...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a graphene preparation method. The method comprises the following steps: mixing a precursor first-order or second-order graphite intercalation compound with 1-10wt% of a reducing solution capable of generating a gas, and allowing the obtained mixture to stand for 1-5min to obtain highly expanded graphite, wherein the reducing solution is an aqueous solution of borohydride or a tetrahydrofuran solution of lithium aluminum hydride; pickling to remove impurities, filtering, carrying out ultrasonic dispersion of the obtained graphite in an aqueous solution or ethanol solution containing 0.5-5wt% of a dispersant for 0.5-3h to obtain a graphene dispersion; and freeze-drying the dispersion to obtain graphene powder, or adding a water-soluble high molecular polymer for co-precipitation to obtain a graphene-containing polymer master batch. The method has the advantages of realization of the repairing of the structural defect of graphene, mild reaction, fast reaction speed; and compared with an oxidative catalysis system, the method disclosed in the invention supplements the peeling of a reducing system in the graphene preparation process, so the graphene quality is further improved.

Description

technical field [0001] The invention relates to the technical field of preparation methods of high-quality graphene, specifically, a graphite intercalation compound formed from an oxidative intercalation compound (such as ferric chloride, bromine, etc.) is used as a precursor, and in a mild reduction system, a small amount of The borohydride aqueous solution or tetrahydrofuran solution of lithium aluminum hydride realizes high-speed expansion, and the method for preparing graphene dispersion liquid with PVP or quaternary ammonium salt aqueous solution / ethanol as the dispersion system. Background technique [0002] Since its discovery in 2004, graphene has been widely concerned by researchers for its excellent mechanical properties, electrical properties, optical properties, thermal properties, and adsorption properties. It is widely used in polymer composite systems, optoelectronic materials, and biomedical fields. , surface adsorption, field emission materials, battery anod...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C01B31/04C08K3/04C08L75/04C08L1/26C08L29/04C08L71/08C01B32/184
Inventor 林治林晓丹
Owner SOUTH CHINA UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap