Distribution of electric field for carbon nanotube assembly: Experiments (II)
(1. Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST),
Daejeon 305-701, Korea;
2. National Core Research Center for Hybrid Materials Solution,
Pusan National University, Busan 609-735, Korea)
Daejeon 305-701, Korea;
2. National Core Research Center for Hybrid Materials Solution,
Pusan National University, Busan 609-735, Korea)
Abstract: The distribution effect of electric field on the alignment and attachment of carbon nanotubes (CNTs) were investigated. The experimental results were compared with the simulation results according to three different shaped electrodes. In previous simulation, the round shaped electrodes were expected to be more effective for aligning and attaching a single CNT between two electrodes than conical or rectangular shaped electrodes. To verify the simulation results, three different shaped electrodes were introduced and a single multi-walled carbon nanotube (MWNT) was attached. The optimal conditions for aligning and attaching MWNTs such as the frequency, applied voltage and concentration of MWNTs solution were investigated. Through repeated experiments, frequency of 100 kHz−10 MHz, applied voltage of 0.3−1.3 Vrms/μm, concentration of 5 μg/mL in MWNTs solution were obtained as a possible condition range to attach MWNTs. Under these conditions, the yield of MWNTs attachment between two electrodes was up to 70%. In previous simulation, furthermore, it was verified that the size of the stable or quasi-stable region made CNTs aligned and attached on different shaped electrodes from the comparison of the experimental and simulation results. Most single MWNT attachment was accomplished on the round shaped electrodes.
Key words: carbon nanotubes; dielectrophoresis; round shaped electrode; simulation