Phytic Acid-Modulated Antifreeze and Self-Healing Hydrogels for Low-Temperature Flexible Sensors

The development of hydrogels that integrate antifreeze, self-healing, and conductive properties is crucial for advancing flexible sensors capable of operating in extreme environments. In this study, we fabricated a multifunctional nanocomposite hydrogel (MPC-P) characterized by antifreeze performance and self-healing capabilities. By utilizing phytic acid (PA) as a key cryoprotectant, the hydrogel’s operational temperature range was successfully extended to −20 °C. To synergistically enhance this antifreeze framework, MXene@PDA/CNC nanocomposites (MPCs) were incorporated, endowing the MPC-P with superior mechanical strength (maximum stress: 2.33 MPa) and high flexibility (elongation at break: 508.6%). Notably, the MPC-P hydrogel retains exceptional performance even at subzero temperatures, exhibiting high self-healing efficiency (90.1% at 25 °C and 84.8% at −20 °C) and rapid response/recovery times (340.0 ms/280.0 ms). These features ensure reliable signal detection under repeated deformation in extreme cold, positioning MPC-P as a promising candidate for next-generation low-temperature wearable electronics.