1. Characteristics and applications of graphene aerogel
Graphene aerogel is a high-strength oxidized aerogel, with high elasticity, strong adsorption, low density, large surface characteristics, known as "carbon sponge".
Graphene aerogel is a three-dimensional porous solid material formed by the aggregation of nanoparticles or polymer molecules, which has been widely concerned for its low density, high electrical conductivity and good elasticity. At this stage, the material of aerogel has been developed to metals, inorganic oxides, polymers, carbon materials, etc., and the application field has also expanded to catalysis, adsorption, energy storage and other aspects.
It is a new type of graphene solid material developed by the professor team of Zhejiang University in 2013, and the material density is only 0.16 mg per cubic centimeter, which is the lightest material in the world so far. It was selected as the top ten scientific and technological progress news in China in 2013 and obtained the Guinness World Record for the lightest solid.
Graphene aerogel is light in weight and large in specific surface area, so it has a high adsorption capacity for pollutants, and has great potential in environmental governance. It can absorb oil and organic dyes in water well, and can recover crude oil after absorption, and the aerogel itself can be reused. This property of graphene aerogel makes offshore oil spills no longer an environmental nightmare in the future, preventing oil from further polluting the ocean and damaging Marine ecosystems. In addition to sewage treatment, graphene aerogel can also be a good insulation from high temperatures. Because the aerogel is made of countless pieces of graphene stacked like building blocks, there are many gaps in the middle, the porous material has poor thermal conductivity and low thermal conductivity, so the heat insulation effect is good; However, graphene aerogel is also a carbon material, which has high temperature resistance and can be used in high temperature insulation applications.
In addition, graphene aerogel can also absorb water, oil, etc., inhibit mold growth, can replace the traditional silica gel and other desiccant, used for shoes, socks, clothing moisture and mildew prevention, while adsorption of fabrics produced in the process of formaldehyde and other toxic gases, eliminate odor. Compared with the traditional desiccant, the adsorption capacity is stronger (the adsorption capacity can reach hundreds of times its own weight), the functional range is wider, a multi-purpose, with wide adaptability, easy processing, low cost, a wide range of adsorbent sources and other advantages.
2. Preparation method of graphene aerogel
A method for preparing a high-strength graphene oxide aerogel is characterized by including the following processes:
1, the graphene oxide powder and deionized water is prepared into a concentration of 0.1-10mg/ml aqueous solution, ultrasonic shock for 0.1-5 hours, to obtain a well-dispersed graphene oxide aqueous solution.
2. Add 10-500ml of the prepared GO aqueous solution to a hydrothermal kettle and treat it at 90-200β for 1-24 hours to prepare GO hydrogel.
3. Put the prepared graphene oxide hydrogel into ammonia, soak 1-36 hours at 0-150β, freeze dry to obtain high-strength graphene oxide aerogel.
The invention has the advantages that the preparation method is simple, and on the basis of the preparation of the graphene oxide aerogel, the mechanical strength can be improved by simple ammonia treatment, with low energy consumption and no pollution, and with the micro-porous structure, it has great application prospects in adsorption and catalysis.
