Fast-moving bimorph actuator based on electrochemically treated millimeter-long carbon nanotube electrodes and ionic liquid gel

Abstract

The development is described of an electromechanical bimorph actuator composed of ionic liquid gel sandwiched by electrochemically treated millimeter-long single-walled carbon nanotubes (SG-SWNT). Electrochemical doping of the SG-SWNT and electrochemical polymerization of polypyrrole on the surface of the SG-SWNT improved the performance of a previously reported actuator using non-treated SG-SWNTs. The conductivity of the SG-SWNT sheets treated at the anodic potential (doped) was found to be three times larger than that of the original film. The generated strain of the actuator prepared from the doped SG-SWNT sheets was increased compared to that prepared from non-doped sample. Moreover, the generated strain of the actuator from the doped SG-SWNT sheets swelled with ionic liquid (IL) was increased to twice that without ILs. The electropolymerization of pyrrole on the surface of the SG-SWNT sheet was carried out. The conductivity of the SG-SWNT was seven times larger after the electropolymerization. The generated strain of the SG-SWNT actuator prepared from the SG-SWNT sheets with electropolymerization was twice as large as that without the electropolymerization at low frequency. At higher frequency, both actuators provide almost the same performance. Both actuators exhibit mechanical resonance at about 100 Hz. © 2012 Taylor and Francis Group, LLC.