Hypervelocity nanoparticle impacts on free-standing graphene: a sui generis mode of sputtering.

The study of the interaction of hypervelocity nano-particles with a 2D material and ultra-thin targets (single layer graphene, multi-layer graphene, and amorphous carbon foils) has been performed using mass selected gold nano-particles produced from a liquid metal ion source. During these impacts, a large number of atoms are ejected from the graphene, corresponding to a hole of ∼60 nm(2). Additionally, for the first time, secondary ions have been observed simultaneously in both the transmission and reflection direction (with respect to the path of the projectile) from a 2D target.