Electrochemical Control of Charge Current Flow in Nanoporous Graphene

Abstract

During the last decade, on-surface fabricated graphene nanoribbons (GNRs) have gathered enormous attention due to their semiconducting π-conjugated nature and atomically precise structure. A significant breakthrough is the recent fabrication of nanoporous graphene (NPG) as a 2D array of laterally bonded GNRs. This covalent integration of GNRs could enable complex electronic functionality at the nanoscale; however, for that, it is crucial to externally control the electronic coupling between GNRs within NPGs, which, to date, has not been possible. Using quantum chemical calculations and large-scale transport simulations, this study demonstrates that such control is enabled in a newly designed quinone-NPG (q-NPG) thanks to its GNRs inter-connections based on electroactive para-benzoquinone units. As a result, the spatial distribution of injected currents in q-NPG may be tuned, with sub-nanometer precision, via the application of external electrostatic gates and electrochemical means. These results thus provide a fundamental strategy to design organic nanodevices with built-in externally tunable electronics and spintronics, which is key for future applications such as bio-chemical nanosensing and carbon nanoelectronics.