(346b) Dispersions of Non-Covalently Functionalized Graphene with Minimal Stabilizer

The dispersion of graphene in solvents often requires excessive quantities of stabilizers (such as surfactants or polymers). We demonstrate that functionalized pyrene derivatives are quite promising for stabilization of single- and few-layer graphene flakes in aqueous dispersions.  The graphene/stabilizer ratio obtained by this method is exceptionally high relative to conventional nanomaterial stabilizers. The mechanism of stabilization by pyrene derivatives were investigated by studying parameters such as  stabilizer concentration, initial graphite concentration, the type and number of functional groups, counterions, and the electronic interaction between the functional groups and the basal plane. Zeta potential measurements were used to quantify the stability of the dispersions as a function of pH. The dispersions were also used to prepare graphene/epoxy composites. These composites displayed mechanical and electrical properties comparable to polymer-stabilized graphene/epoxy composites while containing significantly less impurities.  These dispersions also show promise for applications to organic solar cells, conductive films, and inkjet-printed electronic devices.