Reduced and Functionalized Graphene Oxide: Opportunities for Large Scale Applications

B. Gjoka, R. Wendelbo
Abalonyx As,
Norway

Keywords: graphene oxide, reduced graphene oxide, modification organic molecules, Application, thermal Interface Materials

Summary:

Graphene oxide (GO), an oxidized graphite sheet containing oxygen functionalities on the basal plane and on the edges, provides a convenient intermediate for large scale production of graphene-like materials such as reduced graphene oxide (rGO). In Abalonyx, we provide GO in Kg-scale and to achieve this, a safe and inexpensive process for its production is in place. In this work, to improve the electrical and thermal conductivity of rGO both chemical and thermal reduction were performed applying different reaction conditions. In general, thermal reduction of graphene oxide has shown better results in terms of reduction degree (C/O ratio) compared to chemical methods. The electrical conductivity of the reduced graphene oxide has significantly and dramatically increased. The material obtained in Abalonyx is implemented in different formulation such as paste and sheet, in order to enhance thermal conductivity in electronic applications. For each method applied, the scalability of the process was explored and optimized together with the chemical and physical properties of the modified material. Additionally, to expand graphene oxide-like materials and show its versatility in terms of chemical modification, covalent functionalization with amine groups were performed. As example, amine-based GO have found use in many fields such as composites, catalysis, electronics and water treatment. Such modifications were implemented not only to enhance and modulate the properties of graphene oxide, but also to provide reproducible and scalable functionalized graphene oxide materials which has been Abalonyx focus for more than 7 years. Additionally, these modifications will provide better dispersion in different organic solvents . Different techniques were employed to have reproducible processes for both reduction and functionalization methodologies of graphene oxide, in view of large-scale production. These techniques, such as FT-IR, XRD, XPS; FT-Raman and TGA, were combined to better characterize the graphene- like materials.