Selective edge functionalization for preserving sp2carbon atoms in graphene layers

sp2 carbon allotropes, such as carbon black, carbon nanotubes and graphene related materials can be seen as made by graphene sheets differently assembled. The graphene sheet is the common feature in all the carbon allotropes and it is a substrate for performing chemical reactions. In the present work, functionalization reactions were performed with the aim to introduce functional groups with heteroatoms such as oxygen and nitrogen, without altering the structure of the graphitic substrates. Functionalization was performed by using or pyrrole derivatives or KOH: (i) primary amines were combined with α,δ dicarbonyl compounds and the resulting molecules were able to functionalize sp2 carbon allotropes, with high efficiency. Indeed, the reactions, performed by simply donating either thermal or mechanical energy, were characterized by a yield up to 96% and by an atom efficiency up to 80%. The structure of the graphitic substrates remained substantially unaltered, after the reaction;[1-2] (ii) KOH was reacted with a nanosized graphite with very high surface area (HSAG), higher than 300 m2/g. Polyhydroxylated carbon allotropes were obtained. Layers were then decorated with aldehydic groups, in ortho position with respect to the hydroxyl ones. [