Figure 19

Simulation of dielectrophoretic force fields. Simulated map of ∇E ² in a volume around the electrodes for two orthogonal cross-sections. (A, B) ∇E ² at the surface of the substrate (X Y plane at Z = 0). (C, D) ∇E ² perpendicular to the substrate (X Z plane at Y = 0). The arrows indicate the direction of the force acting on a highly polarizable nanotube–surfactant hybrid and, hence, the direction of nanotube motion. The background color is the magnitude of ∇E ². The dielectrophoretic force is attractive in all regions in the absence of deposited nanotubes (A, C), while the force becomes repulsive between the electrodes, once a nanotube (magenta line) has been deposited (B, D). (Reprinted with permission from Reference [194]. Copyright 2007 American Chemical Society.)