Ultradurable, freeze-resistant, and healable MXene-based ionic gels for multi-functional electronic skin

Hydrogel is a potential matrix material of electronic-skins (E-skins) because of its excellent ductility, tunability, and biocompatibility. However, hydrogel-based E-Skins will inevitably lose their sensing performance in practical applications for water loss, physical damage, and ambient interferences. It remains a challenge to manufacture highly durable gel-based E-skins. Herein, an E-Skin is fabricated by introducing ionic liquids (ILs) into MXene-composited binary polymer network. The obtained ionic gel shows excellent mechanical properties, strong adhesion, and superior tolerance to harsh environments. The E-skin exhibits high sensitivity to both strain and pressure in a wide range of deformations, which enables a monitoring function for various human motions and physiological activities. Importantly, the E-skin shows consistent electrical response after being stored in the open air for 30 days and can be quickly healed by irradiation with 808 nm near-infrared light, originating from the photo-thermal effect induced self-healing acceleration. It is noteworthy that the E-skin also reveals a highly sensitive perception of temperature and near-infrared light, displaying the promising potential applications in the multifunctional flexible sensor.