Chemically Modified Graphene and Their Hybrid Materials: Toward Printed Electronics

Chemically modified graphene has been great interest for the application of printed electronics using solution prossesable technique. Here, we demonstrate a large area graphene exfoliation method with fewer defects on the basal plane by application of shear stress in solution to obtain high quality reduced graphene oxide (RGO). Moreover, we introduce a novel route to preparing highly concentrated and conductive RGO in various solvents by monovalent cation-${\pi}$ interaction. Noncovalent binding forces can be induced between a monopole (cation) and a quadrupole (aromatic ${\pi}$ system). The stability of this RGO dispersion was more sensitive to the strength of the cation-${\pi}$ interactions than to the cation-oxygen functional group interactions. The RGO film prepared without a post-annealing process displayed superior electrical conductivity of 97,500 S/m. Our strategy can facilitate the development of large scalable production methods for preparing printed electronics made from high-quality RGO nanosheets.