Carbon‐Nanotube‐Based Electrical Conductors: Fabrication, Optimization, and Applications

The lack of progress to obtain commercially available large-scale production of continuous carbon nanotube (CNT) fibers has provided the motivation for researchers to develop high-performance bulk CNT assemblies that could more effectively transfer the superb mechanical, electrical, and other excellent properties of individual CNTs. These wire-like bulk assemblies of CNTs have demonstrated the potential for being used as electrical conductors to replace conventional conductive materials, such as copper and aluminum. CNT conductors are extremely lightweight, corrosive-resistive, and mechanically strong while being potentially cost-effective when compared to other conventional conductive materials. However, great technical challenges still exist in transferring the superior properties of individual CNTs to highly conductive bulk CNT assemblies, such as continuous wires, cables, and sheets. This paper gives an overview of the state-of-the-art advances in CNT-based conductors in terms of fabrication methods, characterization, conduction mechanisms, and applications. In addition, future research directions and possible attempts to improve performance are analyzed. The opportunities and challenges for related nonmetal competitive conductors are also discussed.