Electrical behavior at nanometer scale of functionalized graphene-based structural resins

The aim of this work is to demonstrate the ability of Tunneling Atomic Force Microscopy (TUNA) to act as an effective tool for putting together the morphology with local conductivity of epoxy resin filled with functionalized graphene nanosheets (FGN) obtained through the non-covalent modification by π-πstacking interaction between unfunctionalized graphene nanosheets (UGN) and 1-pyrenebutyric acid. The TUNA analysis successfully provides an overview on the effect produced by the proposed functionalization. This innovative technique proved to be truly strategic in detecting the electrical percolation threshold (EPT) thanks to the identification within the graphene-based nanocomposites of nanometric domains characterized by high current density with the formation of a conductive network. The possibility to ascertain low currents also for the sample at lower concentration is tangible proof of the good electrical performance of the formulated nanocomposites and therefore of the effectiveness of the non-covalent functionalization of the graphene sheet surface.