Effect of pH Value on the Electrical Properties of PEDOT:PSS-Based Fiber Mats

Nanofiber mats containing poly(3,4-ethylenedioxythiophene) (PEDOT) hold potential for use in wearable electronic applications. Unfortunately, the use of PEDOT is often limited by the acidic nature of polystyrenesulfonate (PSS), a common dispersant for PEDOT. In this study, we explored the impact of increasing the pH value of PEDOT:PSS/poly(vinyl alcohol) (PVA) precursors on the morphological and electrical properties of the resultant electrospun fibers. Specifically, electrospun nanofibers were analyzed using scanning electron microscopy, bright-field microscopy, and two-point probe measurements. We discovered that neutral and even slightly basic PEDOT:PSS/PVA precursors could be electrospun without affecting the resultant electrical properties. While cross-linking effectively stabilized the fibers, their electrical properties decreased after exposure to solutions with pH values between 5 and 11, as well as with agitated soap washing tests. Additionally, we report that the fiber mats maintained their stability after more than 3000 cycles of voltage application. These findings suggest that PEDOT:PSS-based fibers hold potential for use in wearable textile and sensor applications, where long-term durability is needed.