Preparation method of organic modified graphene

Abstract

The invention discloses a preparation method of organic modified graphene and belongs to the field of preparation of two-dimension nano material graphene. The method is characterized by taking low-cost raw graphite as the raw material, adding different masses of dry ice for creating high-pressure and high-energy environment, preparing graphene via a ball milling method, simultaneously introducing nitrogenous organic matters in the ball milling process, taking nitrogenous organic matters as friction agents and modifiers for simultaneously preparing graphene and carrying out in-situ modification to prepare a nitrogenous organic matter modified graphene structure. Through the preparation method of organic modified graphene, graphene with a circular microstructure is prepared by controlling reaction time, reaction pressure and the ratio of the raw graphite to the nitrogenous organic matters; a low-cost and high-efficiency method for preparing graphene with organic modified surface and complete body structure is developed; the problems of high cost, long preparation cycle, low dispersibility and poor interfacial adhesion caused in large-scale application of graphene are solved; the method has a great significance in industrial production and application of graphene.

Description

technical field [0001] The invention belongs to the field of preparation of two-dimensional nanometer material graphene, and in particular relates to the preparation of an organically modified graphene with a special circular microstructure through a high-pressure high-energy ball milling method. Background technique [0002] Graphene is a honeycomb two-dimensional nanomaterial whose carbon atoms are sp 2 The hybrid form exists, because of its good mechanical properties, thermal properties and electrical properties, it has a wide range of applications in many fields such as composite materials, electrode materials, thermal conductive materials and biological materials. However, the traditional graphene preparation methods all have inevitable shortcomings, which limit the further engineering application of graphene. Such as the mechanical exfoliation method is to obtain graphene by peeling graphite sheets layer by layer by physical methods. The integrity and quality of the r...

AI Technical Summary

Problems solved by technology

Chen Guohua (Journal of Materials Chemistry, 2010, 20 (28): 5817-5819) realized the shear exfoliation of the graphite structure at a low speed (300 rpm) by adding a strong polar solvent DMF into the ball milling system, which can be lower Cost-effective preparation of graphene, but the obtained graphene sheets are too large and easy to reunite, and the organic solvent in the reaction process is difficult to remove

León V (ACS nano, 2014, 8(1): 563-571.) successfully prepared graphene with fewer layers by using melamine as a friction agent and intercalation agent to exfoliate the graphite structure by ball milling. Melamine and graphene sheets are non-covalently cross-linked. The presence of melamine will affect the structure of graphite sheets and reduce its related properties. At the same time, it is difficult to separate excess melamine from graphite after ball milling.

Dai Liming (Proceedings of the National Academy of Sciences, 2012,109 (15): 5588-5593.) has studied adding dry ice in ball milling system and comes the method that exfoliates graphite and prepares graphene, and the graphene edge prepared by this method contains a certain amount of Carboxyl groups, but the obtained graphene has a low exfoliation degree, is difficult to separate and has uncontrollable morphology, and there are still problems such as poor graphene dispersion and interface bonding in further applications.

Generally speaking, due to the problems of easy agglomeration and difficult dispersion in the application of graphene at this stage, in order to meet the requirements of uniform dispersion in the process, graphene oxide is mostly used in practical applications, but the large number of oxygen-containing functional groups between the sheets will cause its sheet The increase of interlayer spacing and the destruction of structural integrity make the performance of graphene itself unable to be fully utilized.

Therefore, there is an urgent need to develop a low-cost and efficient method for preparing graphene with an organic surface and a complete bulk structure to solve the problems of high cost, long preparation cycle, difficult dispersion and poor interface bonding of graphene in large-scale applications.

Images