A method for preparing graphene by using electrostatically accelerated medium flow exfoliation

Abstract

The invention belongs to the technical field of preparation processes of graphene materials and in particular relates to a method for preparing graphene by accelerating medium flow stripping through utilizing static electricity. The method comprises the following steps: mixing a laminar crystallized graphite material, sodium salt and water under the action of mechanical stirring and ultrasounds to obtain graphite slurry; spraying out the graphite slurry through a high-pressure atomizing nozzle provided with a point corona device, so as to form tiny mist liquid drops; meanwhile, carrying out corona treatment on mist liquid drop micro-particles; rapidly gathering negative charges on the surfaces of the graphite micro-particles; finally, splitting the tiny mist liquid drops into single graphite particles under the action of the static electricity; when the electrostatic repulsive force between the charges exceeds an inter-laminar gap of the graphite micro-particles and is further increased, forming expandable graphite particles and electrifying; furthermore, accelerating to strip the graphite into the graphene by utilizing a medium flow accelerated by an electrostatic accelerator. According to the method provided by the invention, an oxidization treatment process is avoided and the graphite is stripped into the single-layered graphene in a high-yield manner; compared with other graphene preparation processes, the single-layered graphene produced by the method has fewer defects and higher electric properties and mechanical properties.

Description

technical field [0001] The invention belongs to the technical field of graphene material preparation technology, and in particular relates to a method for preparing graphene by using electrostatically accelerated medium flow exfoliation. Background technique [0002] Carbon material is a common and special material on the earth. It can form diamond with higher hardness and soft graphite. In the past 20 years, carbon nanomaterials have been the frontier of scientific and technological innovation. In 1985, the rich Both Leene and the carbon nanotubes discovered in 1991 caused great repercussions, and a research boom arose. In 2004, Geim's group at the University of Manchester first obtained a single-layer or thin-layer two-dimensional atomic crystal-graphene by mechanical exfoliation. . The discovery of graphene has enriched the family of carbon materials, forming a complete system from zero-dimensional fullerenes, one-dimensional CNTs, two-dimensional graphene to three-dimen...

AI Technical Summary

Problems solved by technology

The mechanical exfoliation method is a simple and feasible method that can produce high-quality graphene at low cost. However, in order to improve the exfoliation effect during the mechanical exfoliation process, organic solvent intercalation is usually introduced, although it can improve the intercalation reaction to a certain extent. Efficiency and control of particle distribution, but the solvent residues in graphene are not easy to remove and easily cause product contamination

Moreover, the existing mechanical stripping efficiency is low; in addition, the strong pressure of the grinding medium will cause the graphite layer structure to become more compact, which will lead to a decrease in the stripping effect, resulting in long grinding time and very high costs; moreover, the current grinding production of graphene is intermittent. While exfoliating graphite, the exfoliated graphene cannot be screened out in time, so it is difficult to carry out continuous and stable mass production, and it is difficult to carry out large-scale industrial production

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