Purification of Pt-Loaded Carbon Nanoparticles by Dielectrophoresis

Abstract

It is generally di cult to selectively capture speci c nanoparticles from particle mixtures by conventional separation methods, for example, sedimentation and ltration. In the present study, carbon nanoparticles having an average diameter of 27 nm loaded with Pt nanoparticles having an average diameter of 1.9 nm were separated from their mixture with pristine carbon nanoparticles. For the particle-separation experiments, the Pt-loaded carbon nanoparticle (Pt-CNP) was prepared from commercial carbon black by loading Pt from a H 2 PtCl 6 aqueous solution. The electrodes used for dielectropheresis (DEP) separation were fabricated by photolithography, and the target particle mixture was dispersed in ethanol. It was found that the Pt-CNP was puri ed by the present DEP separation. The in uences of the electrode motion speed, the amplitude and the frequency of AC voltage applied on the electrodes, the duration to apply voltage in liquid, and the addition of a surfactant were investigated. It was found that there were optimized values in these operation parameters to achieve a high puri cation factor reaching approximately 92%, and the reasons of these in uences were qualitatively discussed.

JCEJ Outstanding Paper Award of 2014

“…"Puri cation of Pt-Loaded Carbon Nanoparticles by Dielectrophoresis" by Noriaki Sano, Yosuke Iwasaki, and Hajime Tamon, Kyoto University (Sano et al, 2014) Citation: This paper investigates the dielectrophoresis (DEP) separation of Pt-loaded carbon nanoparticles (Pt-CNP) by using patterned Cu electrodes in ethanol. They found four important parameters such as the speed of the electrode lifting motion, the amplitude of AC voltage applied to the DEP electrodes, the frequency of this AC voltage, and the duration of dipping electrodes before lifting.…”