Graphene-based materials are promising due to their high conductivity, low-density and high surface area and therefore ideal materials for the aeronautical industry. However, economic production on industrial scale is yet a problem. At CEST a novel graphene oxide production process was developed to produce high quantities of graphene oxide flakes in reasonable time. Paired with high upscaling potential, this production process states a viable option for bigger scale production and therefore lays the foundation for further industrial applications of graphene-based materials.
The production is based on an electrochemical exfoliation of graphite to produce graphene oxide. On the picture, our current lab-scale reactor is shown consisting of a double-wall cooling, mechanical stirring and electrical contact. After a pretreatment step, the electrochemical exfoliation is executed producing graphene oxide flakes. Ultrasonic Posttreatment is executed to propagate further exfoliation. After Filtration, washing and drying steps, the fine graphene oxide powder is ready for further processing.
The produced graphene oxide flakes can be further processed and modified for the specific application. This includes different chemical and thermal reduction processes to significantly increase the conductivity and provide a viable option as an additive for conductive composite materials. Decoration with high conductive metal nanoparticles like silver or copper also provides benefits for electrical applications within composite materials. Beside these possibilities to promote electrical properties of graphene oxide, also chemical modification with functional groups is possible. With the addition of Si- and P-containing groups, properties like thermal stability, flame inhibition effects and adhesion can be promoted.