Bioinspired Strong and Tough Conductive Hydrogels with Intrinsic Antifreezing Properties for Intelligent Flexible Sensors

Conductive hydrogels have attracted extensive attention due to their designability and wide range of applications. However, their high water content makes them susceptible to freezing at low temperatures, which can damage their flexibility and functional stability, greatly limiting their use in cold environments. Although adding cryoprotectants can lower the freezing point of hydrogels, it may also lead to a decline in their electrical conductivity and pose the risk of cryoprotectant leakage. In this work, we developed a zwitterionic polymer hydrogel inspired by frost-resistant plants, combining intrinsic freezing tolerance, antiswelling property, high conductivity (0.41 S m –1 ), and remarkable mechanical property (tensile strength: 36.1 MPa; toughness: 51 MJ m –3 ) under subzero conditions. This unique combination of properties enables the fabrication of highly durable strain sensors that can provide long-term strain monitoring at subzero temperatures or underwater. This work introduces a strategy for developing conductive hydrogels with intrinsic antifreezing properties, enabling the fabrication of highly durable strain sensors with stable performance in cold and underwater environments.