A Novel Inspection for Deformation Phenomenon of Reduced-graphene Oxide via Quantitative Nano-mechanical Atomic Force Microscopy

The deformation and stacking of graphene significantly affect the overall electronic and mechanical properties. The graphene sheets are easily stacked each other due to van der Waals attraction. The folded characteristic may prevent graphene stacking and increase the d-spacing between graphenes. It can easily form dense graphene structures with high surface area and be applied on electrode materials of battery, nano-composites and so on. The traditional topographic mapping of atomic force microscope (AFM) is hard to measure the characters of surface deformation and distinguish the folding and stacking. In this study, we apply a novel quantitative nano-mechanical AFM to analyze the reduced-graphene oxide (r-GO). The results indicate that the novel AFM system could recognize the difference between folding and stacking of r-GO effectively. Nevertheless, the images including topography, deformation, adhesion, and elastic modulus show the different phenomena between measuring region, which appears that status on measuring region are folding and stacking, respectively.