Method for preparing graphene oxide

Abstract

The invention discloses a method for preparing a graphene oxide. The graphene oxide is prepared from a graphite raw material in a mode that mechanical action and oxidation reaction are combined. The method comprises the following steps of: mixing an oxidant with the graphite raw material, subsequently preparing the graphene oxide by employing mechanical action, adding the oxidant after the graphite raw material is subjected to mechanical action so as to prepare the graphene oxide, and adding the oxidant after the graphite raw material is subjected to mechanical action so as to carry out oxidation reaction and prepare the graphene oxide. According to the method, strong acids and strong oxidants required in a chemical oxidation method are abandoned, so that the introduction of byproducts and impurities is greatly reduced, the separation and the purification are convenient, the process procedures are reduced, the treatment time of a mechanical milling method is shortened, the energy consumption is reduced, and the yield is greatly increased. With the combination of the two methods, the graphene oxide can be prepared at one step within the shortest time, the yield is greater than 20%, the graphite oxide can be stably suspended under a centrifugal condition of 16,000rpm without ultrasound, and the method has the characteristics of rapidness, simplicity, convenience, environmental-protection and efficiency.

Description

technical field [0001] The invention relates to graphene, in particular to a preparation method of graphene oxide. Background technique [0002] Graphene oxide is the oxide of graphene. Graphene oxide is a new type of carbon material with excellent performance, which has a high specific surface area and abundant functional groups on the surface. Graphene oxide is generally obtained by oxidation of graphite with strong acid. There are mainly three methods for preparing graphite oxide: Brodie method, Staudenmaier method and Hummers method. Among them, the timeliness of the preparation process of the Hummers method is relatively good and the preparation process is also relatively safe, which is currently the most commonly used one. It uses potassium permanganate in concentrated sulfuric acid and graphite powder to undergo oxidation reaction to obtain brown graphite flakes with derivatized carboxylic acid groups on the edges and mainly phenolic hydroxyl groups and epoxy groups...

AI Technical Summary

Problems solved by technology

The thermal expansion method and reduction method of graphite oxide in the above method can prepare graphene oxide and graphene in large quantities, but due to the action of a strong oxidant, there are many defects in the structure and the overall performance decreases; methods such as crystal epitaxial growth and chemical vapor deposition are suitable for preparation Large-area graphene is not suitable for the preparation of large-volume, small-area (less than 1mm2 per sheet) graphene or graphene oxide required in many fields