Segregation and Self-Assembly of Binary Colloidal Systems under Dielectrophoresis

Dielectrophoresis has been shown to be effective in controlling the collection of nanoparticles. We extend this idea into binary systems by using microelectrodes to control the segregation and assembly of different sized particles. Although dielectrophoretic separation of binary suspensions has been reported in the past, the bulk structure of the binary system under DEP has not been studied. In this paper, we report on the structural frequency dependence of a binary colloidal system using latex particle suspensions. We also report the effects of medium conductivity, viscosity, and size ratio on structure and summarize with a binary phase diagram. Finally, we speculate the physical phenomena responsible for phase diagram boundaries.