Eco-Friendly Free-Standing Conductive PEDOT-based Nonwovens for Wearable and Flexible Touch Sensors

Abstract

This work focuses on the development of eco-friendly, free-standing conductive nonwovens electrospun from poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and polyethylene oxide (PEO) for applications in flexible and wearable electronics. The study advances the understanding of PEDOT-based nanofiber mats by employing thermal treatment to enhance their conductivity, followed by extensive electrical, mechanical, and electrochemical characterization. A novel aspect of this research is the environmental evaluation of these materials through ecotoxicological assays. Tests conducted on freshwater and marine organisms, including bacteria, algae, and crustaceans, simulate the potential impact of these nonwoven materials on aquatic ecosystems and address both freshwater compatibility and the unexplored marine toxicity. The findings indicate that the PEDOT-based nonwovens exhibit improved conductivity and mechanical strength upon thermal treatment, while maintaining environmental compatibility. The study also demonstrates the practical application of these materials in a sensorized prototype glove suitable for rehabilitation, highlighting their potential for use in advanced wearable technologies. This multidisciplinary approach bridges material innovation and environmental responsibility by examining the sustainable use of conductive polymers in wearable devices. Overall, the findings highlight the intersection of advances in electrospun nanomaterials and environmental sustainability, contributing to advancements in wearable technologies while promoting eco-responsible material usage.

Graphical Abstract

Keywords

Electrospinning / Conductive nonwovens / Flexible wearable sensor / Environmentally compatible nanofibers

References

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Funding

Ministero dell'Università e della Ricerca(PRIN 2022JARFAX)

Consiglio Nazionale Delle Ricerche (CNR)

RIGHTS & PERMISSIONS

The Author(s)