A highly sensitive, eutectic solvent-mediated PEDOT: PSS eutectogel for rehabilitation monitoring application

A eutectic solvent replacement strategy is proposed to synergistically regulate the polymer network and the conductive phase of PEDOT: PSS-based gels. • The optimized eutectogel achieves exceptional fracture strength, toughness and a high gauge factor. • The electrical enhancement involves conformational transition of PEDOT and improved conductivity from metal ion. • The sensor based on PEDOT: PSS eutectogel successfully enables monitoring during post operative cervical spine rehabilitation. Flexible electronics have sparked significant interest for their potential applications in diverse fields. Among these, poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT: PSS)-based hydrogels have emerged as star materials in flexible electronics, yet their sensing capabilities remain constrained by compromised mechanoelectrical coordination. Herein, we present an approach through a eutectic solvent exchange strategy that synergistically regulates mechanical and electrical performance. Specifically, molecular engineering via eutectic solvent-enhanced hydrogen bonding strengthens interchain interactions to improve toughness, while electrical engineering involves (i) conformational transition of PEDOT from coiled benzoid to linear quinoid structure and (ii) the ionic conductivity contributed by Fe 3 + further enhances the conductivity. The optimized eutectogel (MSPFe60) achieves fracture strength (0.98 MPa), toughness (9.97 MJ·m −3 ), and gauge factor (GF= 21.2). We further demonstrate MSPFe60’s potential in postoperative cervical spine rehabilitation monitoring through real-time motion signal capture. Download: Download high-res image (283KB) Download: Download full-size image