A Reversible-Growth Cluster Aggregation Model for Graphene Particle Dispersions

Graphene is widely used as a filler for materials serving in a variety of applications such as polymer composites and the anodes of lithium ion batteries. In these applications, the colloidal dispersions of graphene are used to control the composite structures and the resulting properties of the material. To provide a fundamental basis for the aggregation mechanisms of graphene during consolidation, we have developed a reversible aggregation model based on diffusion-limited aggregation and diffusion-limited cluster aggregation models. The structures produced by this model are in excellent agreement with the experimentally observed structures produced in a system of functionalized graphene sheets dispersed in an aqueous SDS solution. The generalization of this model to predict the structures of fillers in composite materials is expected to be of use in the calculation of the resulting properties of graphene-filled materials.