High Specific Surface Area Pd/Pt Electrode-Based Ionic\nPolymer–Metal Composite for High-Performance Biomimetic Actuation

Abstract

As biomimetic actuators that are\noperable under low voltages, ionic\npolymer–metal composites (IPMCs) have been proposed as promising\ncandidates in the field of artificial muscles. In this study, a high\nspecific surface area was obtained by directional roughening of a\nNafion surface, and high-quality electrodes containing a Pd buffer\nlayer and a Pt layer were deposited on the Nafion matrix via a method\nof isopropanol-assisted electroless plating, achieving outstanding\nelectromechanical properties. The proposed IPMC exhibits an excellent\ntip displacement of 36.5 mm and a large blocking force of 2.4 MPa\nunder a low direct current (DC) voltage. Furthermore, the IPMC has\nan excellent power density (up to 3966 J/m³) and can lift\nobjects that are 20 times its weight, exhibiting great load capacity.\nMore importantly, the imitation of biomimetic actuation behaviors\nincluding the opening/closing of petals and wing flapping of bees\nat a high frequency (21 Hz) has been demonstrated. The fabrication\nof high-quality Pd/Pt composite electrodes provides significant improvement\nfor IPMC actuators, which is useful for their applications in medical\ndevices and biomimetic robots.