Carbon nanotube

Carbon nanotube

Graphene in cylindrical form; SWCNTs (single-walled carbon nanotubes), DWCNTs (double-walled carbon nanotubes) in two layers, and MWCNTs (multi-walled carbon nanotubes) in more layers.
The structure was first proven in 1991 when Dr. Sumio Iijima discovered it while making fullerenes.