Mechanically Robust, Flexible, Fast Responding Temperature Sensor and High‐Resolution Array with Ionically Conductive Double Cross‐Linked Hydrogel

Abstract Hydrogel‐based sensing devices show potential in wearable electronics. However, most hydrogels are mechanically weak, bringing functional stability problems in real usage environment that may interact with occasionally external forces. There are demands to develop robust hydrogel‐based devices with good performances. Here, a highly sensitive temperature sensor with robust, ionic conductive, and double cross‐linked polyacrylamide‐sodium alginate hydrogel is developed. It is found that ions with larger radius show higher sensitivity to temperature changes (e.g., Ba 2+ ) in the hydrogel, because ion movement is dependent with ion sizes. The sensor shows advantages of fast response (2.02 s of 40 °C…

• NN
  National Natural Science Foundation of China

  Awards: 61825403, 61921005
• NK
  National Key Research and Development Program of China

  Awards: 2021YFA1401100, 61921005