Chemical Vapor Deposition, or CVD, is the only bottom-up production method for graphene that is used in an industrial environment. Here, carbon-containing gases are placed in contact with a metal surface under high temperatures (1000°C) and high pressure.
Subsequently, the graphene honeycomb structure is formed on the metal substrate, which serves as a catalyst.
Even though the quality of the graphene produced this way is high, being mostly SLG graphene with very few functional groups or defects, this production method has major drawbacks.
Firstly, current industrial technology is still limited in the size of the graphene surface produced. Secondly, the graphene obtained needs to be transferred from the metal surface to the target substrate.
Methods commonly used for chemical vapor deposition involve wet chemical transfer processes that can contaminate the product. Much research today is still focused on improving these techniques.
OTHER PRODUCTION PROCESSES
Chemical Exfoliation
This top-down approach to obtain graphene in dispersion from graphite is mastered by Carbon Waters.
Mechanical Exfoliation
This exfoliation method was described in 2008 to answer the needs for a scalable production method.
Oxidative Exfoliation
For this exfoliation method, graphite is commonly oxidized under harsh conditions to make graphene.