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Abstract: The conductivity of few‐ and monolayer graphene with covalently bound moieties is a key‐point in the potential application of these materials in any electrical and optoelectronic device. In particular, fluorination of such graphene‐based systems is of interest, as fluorine is expected to have a strong influence on the charge‐carrier density due to its high electronegativity, and therefore modify the electrical transport properties significantly. Here it is shown that, depending on the device architecture, the electrical properties of fluorinated graphene‐based devices are significantly different. It is found that the conductivity of thin films of few‐layer graphene decreases by several orders of magnitude with fluorine content increasing from 2.4 to 16.6 at%, whereas individual flakes show a significant increase in both conductivity and charge carrier mobility. This observation, combined with Raman microscopy study, points toward the fact that the edges of the flakes are primary sites for fluorine within the experimental range of fluorine content. The strong decrease in conductivity in the film devices is therefore associated with the high contact resistance between the fluorine saturated edges of the individual flakes. [ABSTRACT FROM AUTHOR]

The influence of dimensional effects on the compositions and properties of polydicarbonfluoride (C2F) n prepared from multilayered graphenes was investigated. Multilayered graphenes were produced by destructive thermal decomposition of intercalation compounds of 'idealized' (C2F) n that were obtained by reaction of gaseous ClF3 with natural graphite at a room temperature. The precursors of multilayered graphenes have a common formula (C2F⋅ xR) n where R is an organic or inorganic component. It was shown that polydicarbonfluoride prepared from multilayered graphene does not form stable intercalation compound with ClF3, in contrast to polydicarbonfluoride prepared from graphite, that forms its intercalation compound with ClF3 during fluorination of initial graphite in the ClF3 excess. Investigations of polydicarbonfluoride prepared from multilayered graphene showed that it cannot form intercalation compounds with different classes of organic and inorganic compounds as polydicarbonfluoride prepared from graphite can do. The absence of such intercalation activity for polydicarbonfluoride prepared from multilayered graphene can be explained by high exfoliation degree of multilayered graphene (3-4 nm) along the c-axis that results in the presence of two-dimensional (2D) structure properties in multilayered graphene. Dimensional effects transformed the chemical properties of polydicarbonfluoride prepared from multilayered graphene and lowered its decomposition temperature by 150 K in comparison with polydicarbonfluoride prepared from graphite. [ABSTRACT FROM AUTHOR]