Water-triggered microphase reconstruction enables anti-swelling ion transport in amphiphilic ionogels for adaptive multimodal sensing

Water-triggered dynamic reconstruction overcomes conductivity-stability trade-off in ionogels. • Hydrophobic MEA chains form a protective surface barrier while ATU retains bulk ion channels. • The ionogel achieves 8.79 mS/cm conductivity, >4-month water stability, and 85 kPa wet adhesion. • It provides rapid thermal response (−2.54%/°C, 0.1 °C, 510 ms) and quantitative smoke sensing. • Wireless and underwater capabilities enable real-time physiological monitoring and Morse code. Ionogels are promising soft ionic conductors for flexible electronics, yet their operation in wet and underwater environments remains limited by a persistent trade-off between ionic conductivity and aqueous stability. Hydrophilic networks facilitate ion transport and interfacial adhesion but are prone to swelling and ion leakage, whereas hydrophobic networks resist water ingress at the cost of reduced ion mobility and poor compatibility with wet interfaces. Here, we report a water-triggered microphase reconstruction strategy for amphiphilic ionogels that converts water from a destructive medium into an active structural trigger. The ionogel is prepared by copolymerizing hydrophilic N-allylthiourea (ATU) and hydrophobic 2-methoxyethyl acrylate (MEA) in a hydrophobic ionic liquid matrix of [BMIm][TFSI]. Upon water exposure, hydration of ATU-rich regions strengthens hydrophilic-hydrophobic phase incompatibility, driving the rearrangement of PMEA segments toward the outer interface while retaining ionic-liquid-rich domains within the reconstructed network. This adaptive architecture forms a hydrophobic anti-swelling surface layer without sacrificing internal ion-conducting pathways. As a result, the reconstructed ionogel simultaneously achieves high ionic conductivity of 8.79 mS cm −1 , long-term stability for more than 4 months in water, and wet adhesion strength up to 85 kPa. Spectroscopic analysis, surface characterization, Raman mapping, density functional theory calculations, and molecular dynamics simulations collectively reveal the coupling between water-induced phase reconstruction, polymer-ion interactions, and enhanced ion mobility. Benefiting from these integrated properties, the ionogel functions as a robust multimodal sensing platform for underwater strain monitoring, Morse-code communication, high-resolution temperature sensing, wireless physiological monitoring, and smoke detection. This work establishes water-triggered microphase reconstruction as a molecular design principle for adaptive ionogels that require stable ion transport in complex aqueous and biointerfacial environments. Water-Triggered segmental reconstruction in the amphiphilic ionogel concurrently imparts anti-swelling capability and markedly enhanced conductivity. These integrated properties facilitate its application as a multimodal sensor for underwater communication, temperature, and smoke concentration detection. Download: Download high-res image (253KB) Download: Download full-size image