Fluorographene nanosheets with broad solvent dispersibility and their applications as a modified layer in organic field-effect transistors

As the youngest in the graphene family, fluorographene has received numerous expectations from the scientific community. Investigation of fluorographene is similar to graphene and graphene oxide, wherein fabrication is an importance subject in the infancy stage. Fluorographene produced by the currently existing protocols, however, could only disperse in a limited number of solvents, and the dispersions generally exhibit short-term stability, restricting its manipulation and processing. To address this formidable challenge, we herein report that fluorographene nanosheets, most of which have a single-layered structure, could be easily formulated from commercially available graphite fluoride via a one-pot chloroform-mediated sonochemical exfoliation under ambient conditions without any pretreatment, special protection or stabilizers. Significantly, owing to the exceptional volatility of chloroform, our fluorographene originally dispersed in chloroform, could be facilely transferred into other 24 kinds of solvents via a volatilization-redispersion process, wherein dispersions of extremely long-term stability (more than six months) could be obtained. As an example to demonstrate the merit of the as-formulated fluorographene and its potential application possibilities, we further show that our fluorographene could be easily assembled as a modified layer in pentacene-based organic field-effect transistors simply by a spin-coating method, wherein distinctly increased mobility and positively shifted threshold voltage could be achieved. Considering the excellent popularity of chloroform in the scientific community, the remarkable volatility of chloroform, the broad solvent dispersibility of our fluorographene, and together with the long-term stability of the dispersions, our chloroform-mediated sonochemical exfoliation protocol likely endow fluorographene with new and broad opportunities for fabrication of graphene-based advanced functional films and nanocomposites via liquid-phase manipulation or solution-processing strategies.