Carbon nanotube

Allotropes of carbon with a cylindrical nanostructure

A carbon nanotube (CNT) is a tube made of carbon with a diameter in the nanometre range (nanoscale). They are one of the allotropes of carbon. Two broad classes of carbon nanotubes are recognized: Single-walled carbon nanotubes (SWCNTs) have diameters around 0.5–2.0 nanometres, about a 100,000th the width of a human hair.

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