“…11 This functionalized graphite was then subjected to bath sonication in various solvents to exfoliate functionalized graphene sheets. [20][21][22][23][24] Furthermore, because XPS measurement is sensitive to F atoms, the anchored pentafluorophenyl groups make it easier to identify and quantify the functionalities, 32 and more importantly, the inclined nucleophilic substitution of para-fluorine of pentafluorophenyl by sulphur, oxygen and nitrogen nucleophiles 33 makes it possible to attach other functional groups on the edge of graphene sheets. 28,29 So the insertion of solvent molecules into graphite layers will be facilitated by these attached pentafluorophenyl ''wedges'' when sonicating in the solvent, and as a result, the exfoliation of the functionalized graphite might be easier than that of pristine graphite.…”