Ion Clusters‐Driven Strong and Acid/Alkali/ Freezing‐Tolerant Conductive Hydrogels for Flexible Sensors in Extreme Environments

Abstract

AbstractSupramolecular polymer hydrogels, exhibiting wide applications in flexible sensing, wearable electronics, artificial skin, etc., often require complex molecule and component design to adapt extreme environments. Most supramolecular polymer hydrogels currently, however, are unable to satisfy the harsh demands ascribed to their poor mechanical properties and chemical stability. Herein, this study demonstrates a novel strategy to fabricate superstrong polyvinyl alcohol (PVA) hydrogels with densely supramolecular polymer networks (SPNs) and complexation, induced by simple deprotonation and reconfiguration of ion clusters (ICs). Such strategy enables the PVA hydrogels with high strength (9.64 ± 0.5 MPa), compressibility, and recoverability (load objects over ≈10000 times more than its weight), resistance to various solvents, freezing tolerance (keep flexible and conductive even at −50 °C) and many other performances. Notably, the properties of resultant hydrogels surpass majority reported, tackling a long‐standing dilemma both mechanical properties and stability for PVA hydrogels. A proof‐of‐concept spider robot is assembled by 3D printed model, which achieves successfully signal acquisition in different extreme conditions. In this study the multifunctional PVA hydrogels are envisioned as a simple and universal strategy for sensors in various conditions, which is significant for the exploration in extreme environments that are not easily accessible to humans, such as the North and South Poles and solvent leakage area.