Attaching molecules to graphene is required for several applications (for example, attaching bio-molecules to enable bio-sensors), but graphene rejects these molecules. Now researchers from the Universities of Miami and California say that a slight pressure can help functionalize graphene.
It has been shown before that Graphene can participate in Diels-Alder reactions either as the diene or the dienophile, and it is well known that pressure accelerates this reaction. These researchers used polymer tips (80 nm wide), coated them with inks that are Diels-Alder reactants, and applied a gentle force to push the tips into a graphene sheet (the tips were mounted on an atomic force microscope). This created 20 µm by 40 µm patches of graphene decorated with patterns of dye dots.