Electromigration of bivalent functional groups on graphene

Chemical functionalization of graphene holds promise for various applications ranging from nanoelectronics to catalysis, drug delivery, and nanoassembly. In many of these applications, it is critical to assess the rates of electromigration-directed motion of adsorbates along the surface of current-carrying graphene due to the electron wind force. In this paper, we develop an accurate analytical theory of electromigration of bivalent functional groups (epoxide, amine) on graphene. Specifically, we carefully analyze various factors contributing to the electron wind force, such as lattice effects and strong scattering beyond Born approximation, and derive a simple analytical expression forth is force. Further, we perform accurate electronic-structure-theory calculations to parametrize the obtained analytical expression. The obtained results can be generalized to different functional groups and adsorbates, e.g., alkali atoms on graphene.