Multi-walled carbon nanotubes plastic actuator

Carbon nanotubes (CNTs) have electrical and mechanical properties that make them highly attractive for actuators. They have the ability to deform elastically by several percent, thus storing very large amounts of energy, thanks to their crystalline nature and to their morphology. A bimorph actuator composed of single-walled carbon nanotubes (SWCNTs), polyvinylidene difluoride (PVdF) and the ionic liquid (IL) 1-butyl 3-methylimidazolium tetrafluoroborate [BMIM][BF4] with a polymer-supported internal IL electrolyte was previously demonstrated by Aida and coworkers. While several experiments were carried out using SWCNTs, PVdF and a number of ILs, the use of multi-walled carbon nanotubes (MWCNTs) instead of SWCNTs is, to our knowledge, a new result that will be presented here. Electrochemical characterizations by cyclic voltammetry (CV), and actuation tests performed applying a square wave of 4 V peak-to-peak at frequencies between 0.3 and 2 Hz are reported and discussed. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.