A selective dielectrophoretic particle separator using flat electrodes covered with vertically aligned carbon nanotubes

In this short communication, a dielectrophoretic (DEP) particle separator is proposed that is capable of selectively capturing extremely small particles, using flat electrodes onto which carbon nanotubes (CNTs) have been synthesized. CNTs can induce a strong DEP force at their surface, which allows extremely small particles, whose diameters are comparable to those of the CNTs, to be preferably captured by these electrodes. This study experimentally demonstrates that TiO2 particles with diameters of approximately 10-20 nm are selectively captured from a mixture with SiO2 particles with similar diameters by the separator using CNTs grown on the flat electrodes. For comparison, a conventional separator using CNT-grown mesh-stacked electrodes can not exhibit such selective capture from the same TiO2-SiO2 mixture.