Rebar graphene, developed by the Rice lab of chemist James Tour in 2014, uses carbon nanotubes for reinforcement.
Graphene is a one-atom-thick sheet of carbon. On the two-dimensional scale, the material is stronger than steel, but because graphene is so thin, it is still subject to ripping and tearing.
Nanotube rebar diverted and bridged cracks that would otherwise propagate in unreinforced graphene. Nanotubes help graphene stay stretchy and reduce the effects of cracks. This can help flexible electronics, electrically active wearables or other devices where stress tolerance, flexibility, transparency and mechanical stability are desired.
Graphene has the desired conductivity for electronic applications.