A Tough and Conductive AgNWs/PVA Hydrogel Enabled by Ammonium Sulfate Salting‐Out for Wearable Strain Sensor

Conductive hydrogels have gained attention as flexible wearable sensors in human motion detection, soft robots, and human‐computer interfaces. However, developing hydrogels with desirable mechanical and electrical performance still remains challenging. This work reported a facile strategy to fabricate a composite hydrogel by introducing silver nanowires (AgNWs) into polyvinyl alcohol (PVA) matrix via freeze–thaw cycles followed by immersion in ammonium sulfate solution. This salting‐out treatment induced the Hofmeister effect to form a denser, more cross‐linked network within the hydrogel, thus significantly improving pertinent performance. After optimization, the PAW 7 ‐AS 10 ‐180 hydrogel exhibited high mechanical properties (toughness of 3316.51 kJ m −3 , tensile strength of 1.41 MPa, elongation at break > 450%) and electrical conductivity (2.75 S m −1 ). Together with rapid response time (144 ms) and excellent fatigue resistance (> 1000 cycles), such AgNWs/PVA hydrogel sensor offered great potential as a low‐cost wearable sensor for application in flexible and wearable devices.