Variability of C–F Bonds Governs the Formation of Specific Structural Motifs in Fluorinated Graphenes

Fluorinated graphenes (FGs) are key precursors for the synthesis of many graphene derivatives that significantly expand the application potential of graphene-based materials. The reactivity of FGs is rather surprising because the C–F bond is considered to be one of the strongest single covalent bonds in organic chemistry. However, its strength in FGs varies from 25.6 to 118.2 kcal/mol, depending on the configuration of fluorine ad-atoms. This variability is reflected in the formation of specific structural motifs and topological features during fluorination and defluorination processes; whereas defluorination favors formation of π-conjugated chains, following the path of the weakest C–F bonds, fluorination is driven both by thermodynamics and stochasticity, leading to diverse fluorination patterns. Individual motifs vary in their electronic structures, having either metallic or semiconducting character. We rationalize the complex 2D chemistry of FGs using empirical rules that predict the structural and underlying electronic/magnetic properties of these materials.