Rapid room-temperature polymerization strategy to prepare organic/inorganic hybrid conductive organohydrogel for terahertz wave responsiveness

Abstract

Conductive organohydrogel with better environmental stability than conductive hydrogel, has more promising applications in the fields of soft robots, wearable electronics and electromagnetic interference shielding. However, the current organohydrogels still face the trade-off dilemma between environmental stability and conductivity, and their preparation is usually time-consuming and complicated. Here, we report a room-temperature rapid polymerization strategy to prepare conductive organohydrogel using PEDOT:PSS and MXene nanosheets as conductive fillers as well as cross-linking sites, which is applicable to a variety of binary solvent systems. The synergistic effect between PEDOT:PSS and MXene nanosheets activates the formation of abundant hydrogen bonds, chelation interaction and electrostatic interaction between different components, thus significantly shortening the polymerization time from several hours to less than five minutes. Meanwhile, the organic–inorganic hybrid network constructs efficient conductive paths and strengthens the mechanical properties. Over a wide temperature range (−18 to 70 °C), this composite organohydrogel shows excellent stretchability, self-healing, adhesion, environmental stability. More interestingly, the organohydrogel with reasonably designed binary solvent system and conductive network achieves absorption-dominated shielding performance and wireless displacement sensing in the frequency of 2–10 terahertz. The revealed contributions of binary solvent system and conductive network to the absorption and reflection of terahertz waves are conducive to promote the development of organohydrogel-based terahertz responsive materials.