Nobody can shoot a pistol bullet through a banana in such a way that the peel is perforated but the banana remains intact. However, such a feat has now been achieved at the level of individual atomic layers - a nano-structuring method has been developed at the Vienna University of Technology that allows certain layers of material to be perforated extremely precisely and others to be left completely untouched even though the projectile penetrates all layers.
This is made possible with the help of highly charged ions. They can be used to selectively process the surfaces of novel 2D material systems, for example to anchor certain metals on them, which can then serve as catalysts. The new method has now been published in the journal "ACS Nano".