Researchers get carbon nanotube wiring to conduct more like copper

Carbon nanotubes have long fascinated researchers since their discovery, showcasing both metallic and semiconducting properties. These tiny, lightweight structures are incredibly resilient, only yielding under extreme chemical strain. Despite their potential applications, challenges in working with them soon emerged. The primary hurdle has been the difficulty in producing pure forms of these nanotubes. Most synthesis methods result in a chaotic mix of short nanotubes, with longer strands being a rarity. Although the metallic variants exhibit minimal resistance to electric current, effectively channeling large quantities of electrons through them has proven problematic. In a promising development published in today's edition of Science, scientists have introduced a new chemical additive to carbon nanotube bundles, significantly improving their conductivity to levels that approach those of copper. Although these enhanced nanotubes currently lack stability, this research could pave the way for more durable solutions. Carbon nanotubes can be classified into single-walled and multi-walled varieties. Single-walled nanotubes can be visualized as a rolled-up sheet of graphene, with variations in diameter. Multi-walled nanotubes consist of one or more additional layers wrapped around a single tube. While metallic nanotubes allow for seamless electron flow, the majority of their electrons are bound in chemical bonds, limiting their ability to conduct current. This has led researchers to explore the use of dopants—substances that can be introduced in small amounts to modify the properties of materials. In this case, the focus has been on discovering dopants that function as electron donors, thereby increasing the potential for current flow through these remarkable structures.