title: Understanding and optimising the packing density of perylene bisimide layers on CVD-grown graphene.
abstract: The non-covalent functionalisation of graphene is an attractive strategy to alter the surface chemistry of graphene without damaging its superior electrical and mechanical properties. Using the facile method of aqueous-phase functionalisation on large-scale CVD-grown graphene, we investigated the formation of different packing densities in self-assembled monolayers (SAMs) of perylene bisimide derivatives and related this to the amount of substrate contamination. We were able to directly observe wet-chemically deposited SAMs in scanning tunnelling microscopy (STM) on transferred CVD graphene and revealed that the densely packed perylene ad-layers adsorb with the conjugated π-system of the core perpendicular to the graphene substrate. This elucidation of the non-covalent functionalisation of graphene has major implications on controlling its surface chemistry and opens new pathways for adaptable functionalisation in ambient conditions and on the large scale.
authors.affiliation: Centre for the Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and BioEngineering Research (AMBER), Trinity College Dublin, Dublin 2, Ireland. duesberg@tcd.ie.
authors.forename: Nina C
authors.initials: NC
authors.lastname: Berner
authors.forename: Sinéad
authors.initials: S
authors.lastname: Winters
authors.forename: Claudia
authors.initials: C
authors.lastname: Backes
authors.forename: Chanyoung
authors.initials: C
authors.lastname: Yim
authors.forename: Kim C
authors.initials: KC
authors.lastname: Dümbgen
authors.forename: Izabela
authors.initials: I
authors.lastname: Kaminska
authors.forename: Sebastian
authors.initials: S
authors.lastname: Mackowski
authors.forename: Attilio A
authors.initials: AA
authors.lastname: Cafolla
authors.forename: Andreas
authors.initials: A
authors.lastname: Hirsch
authors.forename: Georg S
authors.initials: GS
authors.lastname: Duesberg