Fabrication and Performance of Multisensory Flexible Hydrogel toward Strain, Temperature, and Flame Sensing

The integration of enhanced mechanical properties, sensing capabilities, and thermal safety incorporating fire detection in flexible sensors continues to pose a significant challenge in the fields of materials science and multisensory technology. This study introduces a novel composite hydrogel integrating polyacrylamide (PAM) with graphene oxide (GO) and nickel ions (Ni2+), offering enhanced mechanical strength, conductivity, and multifunctional sensing capabilities. A multifunctional composite hydrogel is developed by incorporating GO into PAM hydrogel, followed by Ni2+ cross-linking. GO's inclusion forms a network with PAM chains via hydrogen bonds and interacts electrostatically with Ni2+, enhancing the hydrogel's mechanical properties and conductivity. Electromechanical tests confirm the hydrogel's efficacy in human motion detection and its potential in thermal safety and fire hazard detection, showcasing a significant advancement in multisensory technology. This composite material holds promise for broad applications in smart wearable devices and safety systems, bridging the gap between material science and practical implementation in safety-critical monitoring systems.