(148c) Separation of SWCNTs by Type Using Electric Field, Field-Flow Fractionation

Modeling of the separation of single wall carbon nanotubes (SWCNTs) in Electric Field, Field-Flow Fractionation (EF-FFF) is examined using a Brownian dynamics method [1], in which the forces and torques arising from an AC electric field acting in the gradient direction have also been incorporated. Two mechanisms for type separation ? separation of metallic from semi-conducting tubes ? are elucidated. In a non-uniform electric field, the dielectrophoretic (DEP) force can be used to induce type separation under normal mode conditions. In a uniform electric field, E-field aligned rods [2] can be induced to exhibit steric inversion, which leads to rapid type separation under steric mode conditions. Both methods rely on exploiting polarizability differences between metallic and semi-conduction tubes [3]. The relative efficiency of the two methods will be compared and discussed.

Reference List

1. F.R. Phelan Jr. and B.J. Bauer, Chemical Engineering Science 62, 4620 (2007).

2. T.B. Jones, in Electromechanics of Particles, (Cambridge University Press, New York, 1995).

3. M.J. Mendes, H.K. Schmidt, and M. Pasquali, Journal of Chemical Physics B 112, 7467 (2008).