MXene/silk fibroin strengthened PVA‐based eutectogel with excellent self‐healing ability and environmental adaptability: Design, synthesis, and sensing application

In order to solve typical problems of instability in a variety of environments, lack of self‐healing ability and poor mechanical properties of traditional hydrogel materials, herein, a superelastic self‐healing eutectogel of DPMS was designed and prepared in a deep eutectic solvent (DES) system using poly(vinyl alcohol) (PVA) as the bulk skeleton material, while two‐dimensional MXene (Ti3C2TX) nanosheets and silk fibroin (SF) as reinforcing fillers. As a result, the prepared DPMS eutectogel possesses a high tensile strength of 7.63 MPa, while its elongation at break can reach 1115.2%, higher than most reported polymer hydrogels (<1000%). Moreover, this eutectogel shows excellent self‐healing ability and can achieve rapid self‐healing within 10 min, and its tensile strength and elongation at break can restore to 84.7% and 97.4% of the initial levels. More importantly, the eutectogel can withstand various environmental conditions, such as atmospheric or even vacuum evaporation and low‐temperature freezing, while maintaining good mechanical and sensing performances. In addition, the eutectogel‐assembled sensor has a high ionic conductivity of 0.61 S/m and a high strain sensitivity of 5.17 kPa‐1. Besides, a stable electrical signal can be transmitted after 200 cycles at 30% strain.