From the link:
A scanning electron microscopy (SEM) image of graphene oxide papers and an analytical model showing the layered structures of graphene sheets, the intralayer and interlayer crosslinks, and an atomic representation of the bridging structure (credit: Yilun Liu et al.)
Scientists at Tsinghua University in Beijing have calculated from first principles what a sheet of graphene might be like.
It’s currently only possible to make graphene in tiny scraps. So they suggest ways to stack these sheets and bond them together to make something larger.
Their model predicts the links between graphene layers will increase the distance between them, thereby reducing the density to about half that of graphite. So graphene paper is not only going to be strong but also very light.