Method for preparing graphene nanoplatelets by viscously mechanical shearing and stripping

Abstract

The invention relates to the technical field of graphene preparation, in particular to a method for preparing graphene nanoplatelets by viscously mechanical shearing and stripping. According to the method, graphite is dispersed in a viscous solution, the viscous solution is quickly connected with surface atoms of graphite crystal after contacting with the graphite crystal, a binding force between the viscous solution and the surface atoms of the graphite crystal is larger than an interlamination bonding force of the graphite crystal, and by taking the advantage of a viscous shearing force of the viscous solution, graphite is gradually stripped in a stirring process to obtain graphene. The method for preparing the graphene nanoplatelets by viscously mechanical shearing and stripping has the advantages of low preparation cost, easiness in control of a preparation process, environment friendliness, simple procedures and promising industrial prospect.

Description

technical field [0001] The invention relates to the technical field of graphene preparation. In particular, it relates to a method for preparing graphene microsheets by viscous mechanical shear exfoliation. Background technique [0002] Graphene is a planar atomic crystal structure in which carbon atoms are closely arranged in a honeycomb shape in regular hexagons. The unique planar structure of graphene makes it possess many characteristics that three-dimensional crystals do not have, such as a specific surface area of ​​up to 2.6×103m2 / g , the thermal conductivity is as high as 3×103W / (m.K), the mechanical properties are 1.06×103Gpa, the Young’s modulus is 1.0TPa, and its mechanical strength is as high as 130Gpa, which is more than 100 times that of steel. Graphene has a stable regular hexagonal lattice structure so that it has excellent electrical conductivity, and the electron mobility is as high as 1.5×10 4 cm 2 / (V.s), which is 2 times higher than the maximum mobili...

AI Technical Summary

Problems solved by technology

However, cavitation is accompanied by a severe process of local high temperature and high pressure, which causes large defects in graphene and unstable quality.

[0006] In the Chinese patent CN103723707A, a method for preparing graphene flakes and the prepared graphene flakes are disclosed, which discloses that highly graphitized graphene is dispersed into graphene flakes by fluid force, but its mode of action requires fluid to pass through A circulatory system containing a nozzle, so that the fluid acts on the surface or side of the highly graphitized graphene, that is, the method of preparing graphene through the force of the fluid requires supporting equipment to be realized, which is not conducive to large-scale promotion

[0007] In another Chinese patent application CN201510174415.5, a method for preparing graphene by rotating and shearing in an electric field environment is disclosed. The experimental device used includes a reaction vessel containing an electrolyte, high-purity graphite as the cathode, and The inert electrode and stirrer, the steps are: connect the cathode and anode to the DC power supply, stir the electrolyte with a stirrer; under constant voltage, the cathode is polarized to peel off the high-purity graphite, and at the same time, the electrolyte is subjected to a certain degree under the action of the stirrer Stir at a high speed, so that the multi-layer graphene stripped off by the cathode is subjected to a shear force again, and a solution containing graphene is obtained; the solution containing graphene is washed, centrifuged, and dried to obtain graphene. This method requires electrochemical Reaction, the reaction process is slow and difficult to control