Heavenly solar flares reach down towards the earth, while green blades of grass stretch upwards, and the two are joined by fine, black threads. The threads are actually single-walled carbon nanotubes, while the sun and earth are comprised of copper sulfide nanoparticles that coat the carbon tubes. These composite materials have applications in advanced lithium ion batteries. Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics and other fields of materials science and technology. In particular, owing to their extraordinary thermal conductivity and mechanical and electrical properties, carbon nanotubes find applications as additives to various structural materials. Nanotubes are members of the fullerene structural family. Their name is derived from their long, hollow structure with the walls formed by one-atom-thick sheets of carbon, called graphene. Nanotubes are categorized as single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs).