Researchers at the German FAU have created defect-free graphene directly from graphite. Using the additive benzonitrile, the team designed a technique to produce defect-free graphene directly from a solution that enables selective electronic properties to be set through the various charge carriers and enables the production of efficient and cost-effective graphene.
The solution benzonitrile (grey circle) removes the causes of possible defects and turns red, resulting in defect-free graphene (red circle).
With the addition of a solvent called benzonitrile, defect-free graphene can be obtained without the formation of any additional functional groups. In addition, the benzonitrile molecule formed as a byproduct of the reaction remains red unless it comes into contact with water or oxygen. This color change helps to easily determine the number of charge carriers in the system with the help of absorption measurements. This could give battery and graphene researchers a new way to determine the charge state, as previously could only be done by measuring voltage.