Analyzing the Structural Behaviour of Conducting Polymer Actuators and its Interdependence with the Electrochemical Phenomenon

Abstract This work reports the deformation behaviour of a conducting polymer poly(3,4-ethylene dioxythiophene):polystyrene sulfonate (PEDOT:PSS)/bacterial cellulose (BC) bi-layered actuator. It was found that the type and magnitude of the movement of actuator was strongly influenced by its width and length. Increasing the actuator’s cross-sectional area (width) would result in an increase in torsional deformation. Further, the maximum tip displacement trivially increased with length, but the degree of bending (curvature) decreased. Because the dimensions of actuator affect its deformation in a non-trivial manner, this can be advantageous from the design perspective in realizing different types of motions without incorporating additional materials. Structural theory and electrochemical impedance Spectroscopy were further used to understand the mechanism of deformations depended on the dimension of a conducting polymer actuator. From the electrochemical impedance spectroscopy results it was understood that the higher bending in actuators of smaller lengths is likely caused by the higher extent of ion penetration within the PEDOT:PSS layer. The electric circuit modeling of the electrochemical impedance data revels the interdependence of the structural behaviour and the electrochemical phenomenon in a conducting polymer actuator.