The effects of suspending medium on dielectrophoretic systems for separating and sorting carbon nanotubes

Document Type : Research Article


1 Department of Chemical Engineering, Faculty of Engineering, University of Sistan & Baluchestan, Zahedan, Iran

2 Innovation Center for Membrane Technology (ICMT), University of Sistan & Baluchestan, Zahedan, Iran

3 Department of Chemical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran


The separation of two different types of multi-walled carbon nanotubes is studied in a dielectrophoresis-based microchannel system in seven different solvents as the suspending medium.  A simple model was developed to predict the behavior of the multi-walled carbon nanotubes in the above mentioned system. Then, the equations of motion for the multi-walled carbon nanotubes in that system were introduced and the effect of the suspending medium type on the fabrication parameters of dielectrophoretic system, such as applied voltage and inter electrode gap, was surveyed. The calculations indicate that the suspending medium has a direct influence on the design and optimization of dielectrophoretic systems. The geometrical separation of the carbon nanotubes is considered here, and it was found that the model predicts some advantages in separation and sorting multi-walled carbon nanotubes based on their diameter. 

Graphical Abstract

The effects of suspending medium on dielectrophoretic systems for separating and sorting carbon nanotubes


  • The separation of CNTs was studied in a DEP system based on electrical properties.
  • The effect of seven solvents as suspending medium on the DEP system was investigated.
  • The suspending medium has a direct influence on the design and optimization of DEP systems.
  • Geometrical separation of CNTs based on their diameter is possible in the DEP system.


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