The synthesis of peculiar structure of spring-like multiwalled carbon nanotubes via mechanothermal method

A simple, economical and convenient mechanothermal process for the synthesis of spring-like multiwalled carbon nanotubes (S-MWCNTs) with advantages of large-quantity production and low cost is described. Interestingly, many peculiar morphologies are reported for the first time as an extraordinary structure from family carbons that could represent unique building blocks for nanoengineering as a result of their special electronic and mechanical properties. As the matter of fact, this special structure guarantees its usage in the world of composites as reinforcement material for good flexible structures. Here, we report the synthesis of S-MWCNTs by annealing amorphous carbon powders at 1380 °C in an Ar atmosphere. The amorphous powders were obtained after ball-milling graphite for times longer than 150 h. The characterization of S-MWCNTs by high resolution transmission electron microscope, scanning electron microscope indicated that S-MWCNTs had uniform tubular hollow structures with openings, a length of about several millimeters, and a diameter of 80 ± 30 nm at the open and closed end. Also, Brunauer–Emmett–Teller indicated surface area as high as ∼210 m2/g. Finally, the magical structure introduced an intermediate structure between two well-known structures as may be of particular interest from both fundamental and applied points of view.