PEDOT:PSS/cellulose nanofibril dynamics in dependence of humidity and temperature in conductive, flexible films

Poly(3,4-ethylenedioxythiophene)(styrenesulfonate) (PEDOT:PSS) is a conductive polymer widely used in flexible electronics and energy devices such as batteries and solar cells. However, its sensitivity to environmental factors such as humidity and temperature poses challenges for long-term performance. Embedding PEDOT:PSS in cellulose nanofibrils (CNF) matrices has been shown to improve mechanical stability and reduce film degradation. In a recent study, we investigate the dynamic behavior of PEDOT:PSS/CNF films under varying humidity (5% and 90%) and temperature conditions (20°C to 70°C) using quasi-elastic neutron scattering (QENS). By examining the diffusive motion of PEDOT and CNF at the nanoscale, we aim to gain deeper insights into how water dynamics and temperature influence the film's morphology and, consequently, its conductivity. Understanding these dynamics is critical for optimizing the material’s performance in real-world applications. Our findings may contribute to identifying the "sweet spot" for hydration water content, balancing conductivity and mechanical integrity, which could further enhance the design of soft, flexible, and conductive films for industrial applications.