Nanoporous carbon-based electrodes for high strain ionomeric bending actuators

Abstract

Ionic polymer metal composites (IPMCs) are electroactive material devices that bend at lowapplied voltage (1–4 V). Inversely, a voltage is generated when the materials are deformed,which makes them useful both as sensors and actuators. In this paper, we propose two newhighly porous carbon materials as electrodes for IPMC actuators, generating a high specificarea, and compare their electromechanical performance with recently reportedRuO2 electrodes and conventional IPMCs. Using a direct assembly process (DAP), wesynthesize ionic liquid (Emi-Tf) actuators with either carbide-derived carbon(CDC) or coconut-shell-based activated carbon-based electrodes. The carbonelectrodes were applied onto ionic liquid-swollen Nafion membranes using a directassembly process. The study demonstrates that actuators based on carbon electrodesderived from TiC have the greatest peak-to-peak strain output, reaching up to20.4 mε (equivalentto>2%) at a 2 V actuation signal, exceeding that of theRuO2 electrodes by more than 100%. The electrodes synthesized from TiC-derived carbon alsoexhibit significantly higher maximum strain rate. The differences between the materials arediscussed in terms of molecular interactions and mechanisms upon actuation in thedifferent electrodes.