Effect of sonication on morphology and dc electrical conductivity of graphene nanoplatelets-thick films

Graphene and its derivatives are nowadays gaining an ever increasing attention for diverse applications, such as supercapacitors, flexible screens and nanocomposites. One of the main challenges still limiting the wide spreading use of graphene-based nanomaterials in electrical and electromagnetic applications consists in the capability of controlling their morphological properties and electrical conductivity through the proper setting of the synthesis route and production process. In this paper graphene nanoplatelets (GNPs) are produced via thermochemical exfoliation of graphite intercalated compound (GIC). The crucial phase of the exfoliation process consists in the tip sonication of the solution containing thermally reduced GIC. The study presented here aims at evaluating the effect of several synthesis parameters, such as the sonication duty cycle and suspension temperature, on the DC conductivity of GNP thick films and on the morphological properties of GNPs.