Covalently Doped Graphene Superlattices: Spatially Resolved Supratopic- and Janus-Binding
Lipiao Bao, Malte Kohring, Heiko B. Weber, Frank Hauke, Andreas Hirsch
Abstract
Rational design and fabrication of graphene nanoarchitectures with multifunctionality and multidimensionality remains quite a challenge. Here, we present a synthetic sequence, based on the combination of two advanced patterned-functionalization principles, namely, laser-writing and poly(methyl methacrylate) (PMMA)-assisted lithographic processes, leading to unprecedented covalently doped graphene superlattices. Spatially resolved supratopic- and Janus-binding were periodically weaved on the graphene sheet, leading to four different types of zones with distinct chemical doping and structural properties. Notably, this is also the first realization of patterned Janus graphene. The elaborate chemical doping with micrometer resolution is unequivocally evidenced by scanning Raman spectroscopy (SRS) and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). The design of the pattern as well as the degree of chemical doping on both opposite sides of graphene can be easily manipulated, rendering exciting potential for graphene nanosystems.