IPMC electromechanical behaviuor using platinum layer aiming green economy

Abstract

Ionomeric Polymer-Metal Composites (IPMCs) are smart materials formed by an electroactive polymer membrane coated on both sides by noble metal electrodes. When an electrical stimulus is applied, an electric field is generated between electrodes, and solvated ions migrate inside the polymeric membrane, causing an internal pressure gradient and bending the device. Despite numerous advantages, it is exceedingly expensive to use noble metals, such as gold and platinum. In addition, the deposition process generates a large amount of toxic waste. Thus, in this work, a Nafion®-based IPMC with a reduced platinum layer (PRIPMC) was prepared and electromechanically tested, comparing it with a reference IPMC (RIPMC). The analyses were performed under precise relative humidity (RH) control. Blocking force and current response were used to evaluate its performance, and the morphology of the Pt layer was evaluated through Scanning Electron Microscopy (SEM). The PR-IPMC presented a 60% thinner electrode layer. The devices performed better when RH = 90%. However, there is just 40% less blocking force compared to R-IPMC. Besides, the reduced amount of platinum complex used to obtain the device represents a saving of reactants and less waste generation, with satisfactory mechanical performance