Until now there have been few studies on the electrochemical behaviors of the electrode surface of Ionic Polymer-
Metal Composites (IPMCs). In general, the electrochemical reactions under imposed electric fields cause the
variations of overall resistance and capacitance of IPMCs and, therefore, lead to changes in the actuation behavior
of IPMCs. The electro-chemo-mechanical interpretation of the electrodes made with Pt and Au are described in
this paper. The standard electrochemical analyses, including voltammetry and electrochemical impedance
spectroscopy on the electrode surface, were carried out in aqueous (water) and non-aqueous (ionic liquid)
environments. The redox behaviors over a wide range of operation were analyzed using the cyclic voltammetry
method. A load cell was used in measuring blocking forces. The experimental results suggest that the selection of
appropriate electrode materials and solvents, and operating conditions are key parameters to predict the
performance of IPMC actuators. It should be pointed out that unwanted reactions caused by the electrocatalyst
under certain conditions can be avoided or minimized when an effective electrode-material is selected. IPMC
samples having highly conductive electrodes or being solvated with ionic liquids generate improved and
repeatable actuation with nearly no relaxation. Also, a thicker IPMC sample than conventional 50-300 micron
thick IPMCs did not show any relaxation behaviors.
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