Atomically sharp edges revealed in a self-folded graphene nanostructure

The crystallographic orientation of the edges of graphene nanostructures is of particular interest as it can strongly affect the electronic, optical, or magnetic properties of the nanostructures. Here, we produced a folded graphene nanostructure by drawing lines on a mechanically exfoliated graphene monolayer while applying a moderate normal force of about 10 nN using an atomic force microscope (AFM) tip[1]. Drawing a line in this way induced self-folding in the graphene monolayer. We acquired several lateral force microscopy (LFM) friction images based on the nanoscale stick-slip phenomenon to investigate the crystallographic orientation of the exfoliated graphene edges and that of the self-folded graphene nanostructure edges. We found that there is a particularly favored crystallographic orientation in the self-folding process, and we will compare our results with previous studies investigating the edges of graphene folded using different methods.