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arXiv · 1507.04525

Understanding and optimising the packing density of perylene bisimide layers on CVD-grown graphene

Nina C. Berner·Sinéad Winters·Claudia Backes·Chanyoung Yim·Kim C. Dümbgen·Izabela Kaminska·Sebastian Mackowski·Attilio A. Cafolla·Andreas Hirsch·Georg S. Duesberg
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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 {\pi}-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.

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Nina C. Berner, Sinéad Winters, Claudia Backes, Chanyoung Yim, Kim C. Dümbgen, Izabela Kaminska, Sebastian Mackowski, Attilio A. Cafolla, Andreas Hirsch, Georg S. Duesberg. 2015-07-16. Understanding and optimising the packing density of perylene bisimide layers on CVD-grown graphene. https://doi.org/10.1039/c5nr04772b

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