Electrolyte-Induced Electrical Disconnection between Single Graphene Nanoplatelets and an Electrode.

We report the influence of electrolyte on the electrical contact between graphene nanoplatelets (GNPs) and an electrode via a single entity electrochemical technique. The current "steps" were observed in the absence of electrolyte due to the GNPs impacting on and bridging across an interdigitated gold electrode array (IDE); in contrast, current spikes of short duration were obtained in the presence of electrolyte. This result indicates that in the latter case the constant short-circuit bridging current was switched off and replaced solely by impacts of GNPs with single electrodes. These observed current spikes measured in the presence of electrolyte are evidenced to be of a capacitative nature, demonstrating the high sensitivity of the electronic properties of the GNP/metal junction to the ionic strength of the electrolytic solution.