NANOGRAPH · The Chemists Way of Making and Utilizing Perfect Graphenes

Graphenes, single sheets of graphite, hold enormous promise as a material of the future, since their unique electronic properties might allow us to combine advantages of silicon and plastics. We propose a concept for the synthesis and processing of mono- and multilayered graphenes and of graphene nanoribbons (GNRs), which are strips of graphene exhibiting a high aspect ratio. The key idea is the dehydrogenation (and planarization) of precursor molecules made from twisted benzene rings. Size and shape of the final graphenes will be chemically determined by the precursors themselves, which can be synthesized with great perfection. This elegant level of structural control of graphenes and GNRs discriminates our approach against existing literature efforts. Defined edges of GNRs are essential for creating finite electronic band gaps, since pristine graphene is a semimetal and thus not suitable for most electronic and optoelectronic applications. Graphenes at a size of several hundred nm will be targeted in solution, but mainly after deposition and transformation of the precursor molecules on substrate surfaces. The consequence is that we will apply and combine organic polymer synthesis and processing with methods of surface physics to create a new materials science of graphenes. Further characteristics of the work will include in-situ monitoring of chemical processes by scanning probe methods and interfacing of as-formed graphenes for in-situ measurements of charge carrier mobility and spin transport. Applications will be demonstrated for the construction of batteries, fuel cells, field effect transistors, and sensors. What we expect as key achievements will be the delineation of reliable structure-property relationships and improved device performance of graphene materials.