Self-limiting assembly of two-dimensional domains from graphene oxide at the air/water interface

Self-assembly is a powerful approach to making new superstructures and high-level hierarchical structures with unique physical/chemical properties from nanosized building blocks. As-prepared graphene oxides (GOs) are in general highly polydisperse not only in size but also in shape. Yet we have demonstrated that such GO sheets tend to assemble into two-dimensional, nearly monodisperse aggregate domains at the air/water interface in a self-limiting fashion, which can be controlled. It was further shown that the self-limiting assembly was driven by the competing interactions between electrostatic repulsion between the negatively charged GO sheets and attractive potentials. This finding provides a convenient platform to understand the forces involved in the 2D assembly and opens a new direction for creating novel materials and structures at the air/water interface. © 2012 American Chemical Society.