Polyaniline nanofibers as a novel electrode material for fault-tolerant dielectric elastomer actuators

Abstract

Polyaniline nanofibers (Pani nanofibers) have exhibited high performance and fault tolerant properties for dielectric elastomer actuator devices. Electrodes comprised of uniformly sprayed Pani nanofibers in thicknesses 0.7 μm, 1.1 μm, 1.3 μm, and 1.5 μm have shown the following high strains: 65% in area for 0.7 μm electrodes at 3 kV, 97% in area for 1.1 μm thick electrodes at 3.5 kV, 84% in area for 1.1 μm thick electrodes at 3 kV, and 114.% in area for 1.5 μm thick electrodes at 3.5 kV. Optimal performance was achieved with actuators with electrodes 1.1 μm thick, which demonstrated self-healing properties at 3 kV. These actuators displayed a preserved strain of 91% after the clearing and sustained a 93% area strain for 10 minutes at 3 kV. Devices with 1.1 μm thick electrodes were also able to perform 700 actuation cycles over a total duration of 75 minutes with a pulsed half-sinusoidal voltage of 3 kV. Mechanical compliance tests performed on a film with a 1.1 μm thick Pani nanofiber electrode reveals that the electrode material does not significantly alter the mechanical properties of the film. The estimated Young's modulus was found to be 32 MPa for the film with the electrode and 31 MPa for the film itself.