Strong and Tough Water‐Tolerant Conductive Eutectogels with Phase‐Separated Hydrophilic/Hydrophobic Dual Ionic Channels

Abstract

AbstractEutectogels are emerging as the next‐generation stretchable electronics due to their superior ionic conductivity, non‐volatility, and cost‐effectiveness. Nevertheless, most eutectogels suffer from weak mechanical strength and toughness and pronounced hygroscopicity. Herein, a strategy is proposed to fabricate phase‐separated eutectogels with dual ionic channels (PSDIC‐gel), which exhibit exceptional integrative properties, especially water resistance. By blending hydrophilic/hydrophobic polymerizable deep eutectic solvents, dual ionic channels spontaneously form via polymerization‐induced phase separation. The hydrophilic poly(acrylic acid) (PAA) phase containing Li+‐channels, rich in hydrogen bonding and ion‐dipole interactions, provides mechanical strength and conductivity. The hydrophobic poly(hexafluorobutyl acrylate) (PHFBA) phase incorporating cholinium cation (Ch+) channels enhances toughness, conductivity, and water resistance. Adjusting the phase ratio yields a microphase‐separated transparent eutectogel with high tensile strength (6.03 MPa), toughness (16.18 MJ m−3), excellent ionic conductivity (1.6 × 10−3 S m−1), strong substrate adhesion, and rapid room‐temperature self‐healing. Solid‐state NMR reveals the conductive mechanism and the phase‐separated structure featuring dual ionic channels in PSDIC‐gels, advancing the understanding of complex ionic interactions at the atomic level. The PSDIC‐gel enables a flexible triboelectric nanogenerator for accurate real‐time self‐powered human motion sensing. This work advances eutectogel design through structure‐property engineering, offering a universal strategy to reconcile mechanical robustness, environmental suitability, and ionic conductivity for wearable electronics.