A kind of preparation method of graphene microsphere

Abstract

The invention discloses a preparation method of graphene microspheres. The preparation process comprises: 1) adjusting the pH value of the water phase system to 9-11 with an alkaline compound in an aqueous solution of graphene oxide; 2) preparing liquid paraffin and carbon tetrachloride Composite oil phase system, the volume ratio of liquid paraffin and carbon tetrachloride is 6:1 to 15:1; 3) Add surfactant to the composite oil phase system, and then add the water phase system in the above 1), the oil phase / The volume ratio of the water phase is 2:1-8:1, and the diamine compound is added, stirred and reacted at 40-100° C. for 3-8 hours to obtain graphene oxide microspheres. The invention adopts the action of diamine-based compounds in the inverse emulsion system containing the composite oil phase, so that graphene can be assembled together by hydrogen bonds or van der Waals force, so that it has uniform and controllable size distribution, sufficient strength and porous structure. structure, forming and maintaining a high-strength porous spherical shape, expanding the application range of graphene in catalyst supports.

Description

technical field [0001] The invention relates to a method for preparing spherical graphene, in particular to a method for preparing graphene microspheres by an inverse emulsion method. Background technique [0002] Graphene is a new material with a single-layer sheet structure composed of carbon atoms. It is a planar film composed of carbon atoms in a hexagonal honeycomb lattice with sp2 hybrid orbitals. It is only one carbon atom thick ( 0.334nm) two-dimensional material. Graphene is not only the thinnest known material, but its theoretical specific surface area is 2630m2 / g, and 1.0g of graphene can cover the entire football field. It also has very high mechanical properties, with a theoretical strength of 130GPa; When graphene is used as raw material to prepare polyolefin catalyst carrier, the carrier material has very good mechanical strength, which effectively guarantees the mechanical strength of the carrier material during the polymerization reaction, and has a large s...

AI Technical Summary

Problems solved by technology

[0003] At present, there are roughly four methods for obtaining flake graphene materials; one is to use the mechanical exfoliation method, that is, the graphite flakes are first peeled off from the graphite, and then the two sides of the graphite flakes are stuck on a special adhesive tape. At the same time, the graphite sheet is separated. This method is easy to operate, but the size of the prepared graphene is limited, and the number of layers of graphene cannot be controlled.

The second is the chemical vapor deposition (CVD) method. Large-area high-quality graphene can be prepared by the CVD method, but there are still some problems to be solved in this method.

The third is the epitaxial growth method, that is, by heating a large area of ​​single crystal SiC at high temperature to grow graphene on it, removing Si under ultra-vacuum or normal pressure to leave C, and then obtaining a graphene thin layer with an area similar to that of the original SiC , but the graphene produced by this method still cannot achieve a uniform thickness, and the different substrate materials used will have different effects on the growth of graphene, making it difficult to separate graphene from the substrate material

[0013] In short, although various methods in the prior art can obtain spherical graphene, the preparation method is mostly a physical condensation process. Because the intermolecular force formed by the surface tension of the liquid is weak, the mechanical strength of the obtained graphene sphere is generally low, which limits its use. Applications in many fields, especially in the field of catalyst supports

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