Ion-Electron Dual-Mode Conductive Gel with Multi-Dynamic Crosslinked Networks for Integrated Self-Powered Wearable Sensing Systems

Abstract

Conventional conductive gels for wearable strain sensors have been fundamentally limited by their dependence on external power sources, interfacial issues with electrodes and the inherent trade-off between conductivity and mechanical properties. To overcome these critical challenges, we developed an innovative ion-electron dual-conduction mechanism combined with an impregnation strategy, leading to the successful fabrication of an integrated "electrode-electrolyte-electrode" structured conductive gel (PAML-EG/LiCl-PANI). The combination of the ternary deep eutectic solvent PDES (choline chloride/acrylic acid/acrylamide) with LiCl established efficient ion pathways, while in situ polymerization of polyaniline formed a continuous electronic network. Furthermore, the introduction of lauryl methacrylate (LMA) and cetyltrimethylammonium bromide (CTAB) micelles generated hydrophobic microdomains, combining with the dynamic hydrogen bonding and electrostatic interactions of PDES to form a multiscale energy dissipation network. The resulting gel exhibits outstanding electrical conductivity (21.84 mS/cm) and ultrahigh fracture elongation of 4425 ± 187%. When employed as a strain sensor, the gel displays rapid 440 ms response times and high sensitivity with gauge factors up to 19.71. As all-in-one supercapacitor, it achieves remarkable areal capacitance of 131.23 mF/cm² while maintaining excellent pressure tolerance and self-healing capability during operation. The self-powered sensing platform constructed from this multifunctional gel successfully achieves real-time monitoring of human motion states without external power requirements. These findings establish a new material-device codesign paradigm that simultaneously optimizes mechanical robustness, electrochemical performance and sensing capability, representing a significant advancement in the field of autonomous wearable electronics.

Keywords: all-in-one supercapacitors; ion-electron dual conduction; multilevel dynamic cross-linking; self-powered sensing system; strain sensor.