(69e) Manufacture and Characterization of Carbon Nanotube Microcable

Carbon Nanotubes (CNTs) have gained attention over the past two decades because of their extraordinary strength and electrical properties. CNTs are a good candidate to replace copper wire for electric power distribution because of their corrosion resistance, low density, and high cycle fatigue. At the University of Cincinnati’s Nanoworld Labs, CNTs are grown on a silicon wafer substrate by a Chemical Vapor Deposition process. CNTs are then “spun” in a similar fashion as silk into a macroscopic thread (CNT thread). This CNT thread is about half the width of a human hair. The objective of the reported research efforts was to determine the most effective way to improve the electrical properties of CNT thread. Currently, the conductivity of “as spun” CNT thread is around three orders of magnitude lower than copper. By post treatments, we have been able to achieve conductivity of 10⁵ S/m, which is about two orders of magnitude lower than that of copper. In addition, experiments have been conducted to coat the CNT thread with a polymer making its surface insulating as that of a metal electric cable. We expect further improvement in the electrical conductivity of CNT thread which will allow using it in electromagnetic devices, thus replacing copper wire and reducing the weight of the devices.