A wearable, self-adhesive, long-lastingly moist and healable epidermal sensor assembled from conductive MXene nanocomposites

Abstract

MXene nanocomposites exhibit self-healing capability, self-adhesive performance and long-lasting moisture, and can be assembled as epidermal sensors to wirelessly detect human motion.

MXene‐Based Conductive Organohydrogels with Long‐Term Environmental Stability and Multifunctionality

“…Apart from the freezing issue, dehydration is another challenge for conventional hydrogels. [ 11,13 ] In this study, the water‐retaining ability of the PTCM‐Gly organohydrogels was assessed based on a weighting method. As shown in Figure 3d, the Gly5 organohydrogel could maintain more than 80% of its initial weight after storage in an open environment (relative humidity: 35–45%, temperature: 20–25 °C) for 7 days.…”

“…Tensile testing results illustrate that even the stretchability of PTCM-Gly5 slightly decreases at −24 °C compared to room temperature, the sample could still reach a stretch strain of ≈1380%, confirming Apart from the freezing issue, dehydration is another challenge for conventional hydrogels. [11,13] In this study, the water-retaining ability of the PTCM-Gly organohydrogels was assessed based on a weighting method. As shown in Figure 3d, the Gly5 organohydrogel could maintain more than 80% of its initial weight after storage in an open environment (relative humidity: 35-45%, temperature: 20-25 °C) for 7 days.…”

“…Recently, several antifreezing and nondrying hydrogels have been fabricated by introducing low‐volatile cryoprotectants, such as ethylene glycol (EG) and Gly, into the hydrogels (so‐called organohydrogels). [ 11–13 ] In these cases, the water molecules in the hydrogels are partially replaced by organic agents (such as EG, glycerol, or sorbitol), which form strong hydrogen bonds between the agents and the water molecules that compete with the original hydrogen bonds in water, resulting in an enlarged working temperature range and decreased drying speed of the resultant organohydrogels. However, despite the great improvement in the environmental stability, the conductivity of the organohydrogels is reduced owing to the decreased water content, which restricts their potential application in the field of wearable strain sensors.…”

“…Recently, several antifreezing and nondrying hydrogels have been fabricated by introducing low-volatile cryoprotectants, such as ethylene glycol (EG) and Gly, into the hydrogels (so-called organohydrogels). [11][12][13] In these cases, the water molecules in the hydrogels are partially replaced by organic agents (such as EG, glycerol, or sorbitol), which form strong hydrogen bonds between the agents and the water molecules that compete with the original hydrogen bonds in water, resulting in an enlarged working temperature range…”

Enzyme-Regulated Healable Polymeric Hydrogels

“…Self-healing materials with enhanced longevity and reliability as next-generation materials for the realization of a sustainable society have attracted much attention from scientists 6 , 62 and also have found widespread applications in many fields, such as biosensors, 84 , 85 drug delivery systems, 58 , 86 and electronic devices. 87 , 88 Intrinsic self-healing of materials based on the kinetic lability of chemical bonds or physical interactions is one of the research hotspots in healable and renewable materials science because it allows for multiple local healing events to occur.…”