  The unique topology and exceptional properties of carbon nanoscrolls (CNSs)
have inspired unconventional nano-device concepts, yet the fabrication of CNSs
remains rather challenging. Using molecular dynamics simulations, we
demonstrate the spontaneous formation of a CNS from graphene on a substrate,
initiated by a carbon nanotube (CNT). The rolling of graphene into a CNS is
modulated by the CNT size, the carbon-carbon interlayer adhesion, and the
graphene-substrate interaction. A phase diagram emerging from the simulations
can offer quantitative guideline toward a feasible and robust physical approach
to fabricating CNSs.
