Piezoionic sensors based on formulated PEDOT:PSS and Aquivion(R) for ionic polymer-polymer composites

In this work, an ionic polymer-polymer composites (IP2Cs) was developed as piezoionic sensors based on Aquivion(R) perfluorinated conducting membranes and modified PEDOT:PSS electrodes. The influence of solvent annealing, additive concentration and its nature (ionic liquid (IL), Aquivion(R), horizontal ellipsis ) on the electronic conductivity and the mechanical properties of modified PEDOT:PSS electrodes is investigated. The design of flexible free-standing PEDOT:PSS electrodes provides a new way of IP2Cs conception. Tri-layers are elaborated either by drop-casting or by thermocompressing of electrodes on top of commercial Aquivion(R) membranes swelled by an IL 1-ethyl-3-methylimidazolium bis (trifluoromethyl-sulfonyl) imide. The open-circuit voltage output is measured during bending stimulation experiments as function of the mechanical perturbation amplitude. These IP2Cs made from Aquivion(R) behaves as soft mechanical strain sensors with large electrical output signal as high as Delta E = 2.9 mV (Delta epsilon = +/- 2%) under optimal conditions. The influence of the IP2C's manufacturing process, grade of Aquivion(R) membrane, and electrode's properties is investigated. This study emphasized the significant contribution of the electrode's mechanical properties that appears as a critical parameter for the development of high performance piezoionic sensors. In the near future, we will explore the opportunity to employ these Aquivion(R)-based IP2Cs as soft strain sensors for robotic and medical applications.