Method for preparing graphene

Abstract

Disclosed is a method for preparing graphene. In particular, the method comprises: using n-hexane or propane as a supercritical solvent, filling graphite powder or graphite powder and a cosolvent into an autoclave, sealing the autoclave by selecting an appropriate rupture disk, adding n-hexane or propane after the autoclave is vacuumized, keeping in a supercritical state for a period of time at a temperature and a pressure, then increasing the temperature and the pressure slightly or increasing the pressure alone,, and a collector collecting rushed-out materials instantly for treatment to prepare a graphene product after the rupture disk bursts when the pressure exceeds the pressure which the rupture disk can bear. In the present method, pressure relief occurs in milliseconds, and thereby efficient strip of graphite can be achieved. The method belongs to a physical process, does not cause large damage on the structure of graphene, is simple in the preparation process, does not require a large quantity of inorganic acids and oxidants, and is free of "three wastes". The prepared graphene crystal is intact in structure, good in quality, and capable of achieving large-scale industrial production of graphene.

Description

technical field [0001] The invention relates to a method for preparing graphene products, in particular to a method for preparing graphene by means of steam explosion. Background technique [0002] The appearance of graphene has aroused great repercussions in the scientific community. Because of its extraordinary electrical conductivity, strong strength and toughness, good light transmission, etc., it has triggered a strong research boom in the field of modern electronic technology. Graphene is both the thinnest material and the strongest, with a breaking strength a hundred times higher than the best steel. At the same time, it has good elasticity, and the stretching range can reach 20% of its own size. Although the discovery time of graphene is very short and it is still in the research stage, its unique physical structure and excellent mechanical and electrical properties make it have broad application prospects in the fields of nanoelectronics, microelectronics, composit...

AI Technical Summary

Problems solved by technology

Chinese patent 201110021033.0, "Method for preparing graphene with supercritical fluid", this method repeatedly uses high pressure (10-100 MPa) and temperature (200-700°C), and there are many repeated steps in the preparation, making it difficult to achieve industrial-scale preparation

However, the above methods all use rapid pressure relief, which cannot achieve instantaneous (millisecond level) pressure relief, so it is impossible to instantly (millisecond level) release all the materials in the high-pressure container, and the stripping effect on graphite is limited.

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