Mobile aryl groups on graphene

Abstract

Molecular Diffusion Phenyl groups on aromatic rings can migrate to an adjacent carbon atom under acidic conditions through an ipso arenium ion intermediate. He and Swager show that analogous migration of aryl groups on p-doped graphene surfaces can occur if functional groups weaken the bond to graphene. They patterned graphene with a copper mask to create circular islands of phenyl, 4-trifluoromethylphenyl, and 4-methoxyphenyl groups. Upon oxidative etching of the copper, which leads to p-doping of the graphene, Raman imaging showed that the aryl pattern remained for the first two groups. For 4-methoxyphenyl, migration of these groups several micrometers from their original position occurred through a random walk. J. Am. Chem. Soc. 142 , 17876 (2020).