Question

What name is given to the carbon-based structures used in lubricants and nanotubes

Answer 1

Answer:

Fullerene, also called buckminsterfullerene, any of a series of hollow carbon molecules that form either a closed cage (“buckyballs”) or a cylinder (carbon “nanotubes”).

Explanation:

A fullerene is an allotrope of carbon whose molecule consists of carbon atoms connected by single and double bonds to form a closed or partially closed mesh, with fused rings of five to seven atoms. The molecule may be a hollow sphere, ellipsoid, tube, or many other shapes and sizes.

Answer 2

Answer:

khansamueen has already provided an answer.  This is an additional note on the many structures carbon may form, called allotropes.

Explanation:  Carbon can take on many forms.  They are all based only on the carbon atom, and are thus called alloptropes.  One of these is diamond, "a" in the attached image.