  Single-layer and bilayer carbon and hexagonal boron nitride nanoscrolls as
well as nanoscrolls made of bilayer graphene/hexagonal boron nitride
heterostructure are considered. Structures of stable states of the
corresponding nanoscrolls prepared by rolling single-layer and bilayer
rectangular nanoribbons are obtained based on the analytical model and
numerical calculations. The lengths of nanoribbons for which stable and
energetically favorable nanoscrolls are possible are determined. Barriers to
rolling of single-layer and bilayer nanoribbons into nanoscrolls and barriers
to nanoscroll unrolling are calculated. Based on the calculated barriers
nanoscroll lifetimes in the stable state are estimated. Elastic constants for
bending of graphene and hexagonal boron nitride layers used in the model are
found by density functional theory calculations.
