Folding of graphene into elastic nanobelts

Here we report the finding of a new crumpled graphene structure - folded graphene belts (FGBs) - generated by means of shock cooling of an aqueous chemically converted graphene (CCG) dispersion. Unlike the traditional tubular hollow structures such as CNTs or CNSs, the as-made FGBs feature an accordion-like geometry in which the 2D graphene sheets were folded along multiple parallel axes. In situ scanning electron microscope (SEM) measurements revealed that the prepared FGBs were highly elastic and can keep their shape under repeated large strains. The formation and growth of ice crystals during the shock cooling step in liquid nitrogen are believed to be the driving force for the formation of such unique folded graphene structures.