Influence of AC Electric Field on Dispersion of Carbon Nanotubes in Liquids

Abstract

Production processes for carbon nanotubes commonly produce mixtures of solid morphologies that are mechanically entangled or that self‐associate into aggregates. The entangled or aggregated carbon nanotubes often need to be dispersed in liquids for further applications. The authors propose an innovative dispersion method for carbon nanotubes by which an AC electric field is applied to suspensions of carbon nanotubes. The dispersion status of carbon nanotubes in liquid media is evidently improved by an AC electric field and is strongly dependent on the magnitude, the frequency, and the exerting time of the applied electric field. Fine carbon nanotube dispersion is achieved with an AC electric field of high voltage, low frequency, and proper exerting time. A certain relation between the dispersion status and the current between the metal electrodes through the carbon nanotube suspension is also observed. The dispersion of carbon nanotubes is ascribed to the AC electric field induced simple harmonic motions with different amplitudes of different carbon nanotubes.

Keywords:

• Carbon nanotubes
• dispersion
• AC electric field
• current

Acknowledgments

This project was sponsored by the Foundation of National Natural Science, China (Grant No. 10332020) and the Innovation Fund for Outstanding Scholar of Henan Province, China (Grant No. 0521001000).