Spatially Resolved Bottom-Side Fluorination of Graphene by 2D-Substrate Patterning.

Patterned functionalization, which can on the one hand open the bandgap of graphene and on the other hand program demanding designs on graphene, is essential for graphene-based nano-architectures. Here, a new and highly efficient method was applied to obtain patterned functionalization on graphene by the mild fluorination with spatially arranged AgF arrays on the structured substrate, which was directly demonstrated by Scanning Raman Spectroscopy (SRS) and Scanning Electron Microscopy coupled with Energy-dispersive X-ray Spectroscopy (SEM-EDS). For the first time, chemical patterning on the bottom-side of graphene was realized. The chemical nature of the patterned functionalization is established to be the ditopic scenario with F-atoms occupying the bottom-side and moieties like oxygen-containing groups or H-atoms binding on the top-side, which further discloses the mechanism of the fluorination process. Our novel strategy can be conceptually extended to pattern other functionalities by using other reactants and this bottom-side patterned functionalization releases lots of possibilities on the top-side, enabling great potentials for graphene-based devices.