Synergistic effect of a r-GO/PANI nanocomposite electrode based air working ionic actuator with a large actuation stroke and long-term durability

Abstract

Actuators can directly convert various types of energy into mechanical motions. In this work, we constructed a novel air working ionic actuator by sandwiching sulfuric acid–poly(vinyl alcohol) (H₂SO₄–PVA) gel electrolyte between two pieces of reduced graphene oxide/polyaniline (r-GO/PANI) nanocomposite film based electrode, in which the PANI nanoparticles were uniformly decorated onto the r-GO sheet surfaces through an in situ polymerization method. A combination of the supramechanical properties, electrical conductivity, large surface area of the individual graphene sheets and excellent electrochemical properties of the PANI component results in the composite electrode having good mechanical properties and a high electrochemical capacitance. Later tests indicated that the actuator could be stimulated under a low driving voltage (≤0.5 V) without trade-off actuator strokes, and showed excellent long-term actuation durability. Under a 0.5 V operating voltage, the actuation strain of the r-GO/PANI actuator could reach 0.327%, corresponding to a 30 MPa generated stress. We attribute the excellent actuation performance to the synergistic effect of the r-GO sheets and the PANI component.