Materials & Design (May 2023)
High-performance ionic polymer actuators with Triple-layered multifunctional electrodes
Abstract
Ionic polymer actuators have attracted attention in recent years due to their remarkably large strain under low-voltage stimulation. However, a key challenge for fabricating high-performance ionic polymer actuators is to develop a firm electrode with high electrical conductivity and electrochemical performance. Herein, inspired by the structure of zoysia grass, we proposed an efficient method to prepare the triple-layered multifunctional electrodes capable of low surface resistance (∼3.4 Ω/□), high adhesion (∼328 KPa) and good electrochemical performance for ionic polymer actuators. Through the spraying and impregnation-electroplating (IEP), three functional layers of multifunctional electrodes are obtained, including MWCNTs/Nafion interfacial layer, Ag NWs fixed layer and Ag NWs@Au layer, which respectively contribute to the charge storage in the electrode, high strength and the uniform and fast charge distribution. The synergic effect of these three functional layers maintains a high stability of multifunctional electrodes after being immersed in DI water for 7 days or 1500 bending cycles, and greatly enhances the actuation performance of ionic polymer actuators, resulting in an extreme bending deformation (increasing by 460%). This work represents an important step towards ionic polymer actuators where the synergic effect in electrodes plays an important role in promoting electrochemical actuation performance.