Researchers Mass Produce Graphene Nanosheets

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Graphene is made from graphite and is claimed to be one of the most important synthetic material of the 21st century. Graphene sheets are better conductors of electricity and heat. They are harder than diamond and yet they stretch. And, now researchers in South Korea and Case Western are working to mass produce high quality graphene nanosheets that will revolutionize computing and electronics.

The most widely used method for producing graphene is that of acid oxidation, which means the process involves application of toxic chemicals. But, the method will be different; it involves placing graphite and frozen carbon dioxide in a ball miller (a canister full of steel balls). After turning the canister for two days, flaky graphite was produced and it had carboxylated edges. This made it soluble for protic solvents and polar aprotic solvents.

Once in the solvent, the graphene flakes disperse and separate into nanosheets with five or less layers. For testing their efficiency in electronics, the material was compressed into pellets and it was found that they were 688 times better in conducting electricity.

When these pellets were heated at 900 degree Celsius for two hours, its edges would become decarboxylated. For forming large graphene nanosheet films, the edge carboxylated graphene nanosheets and a solution of solvent were cast on a 3.5 centimeter wafer and then heated at 900 degrees Celsius. This process is carried out till you till you get the desired wafer size.

Via: Think