Stretchable, self-adhesive, and conductive hemicellulose-based hydrogels as wearable strain sensors

Conductive hydrogels have recently gained impressive attention in flexible sensing. However, their low sensing limit and poor interface matching have raised great concern during the practical application. Therefore, incorporating excellent stretchability and adhesiveness into conductive hydrogel is highly desirable but still be a huge challenge. In this study, we synthesized composite hydrogels with desired properties by utilizing the synergistic role of hemicellulose (HC) and conductive two-dimensional material MXene. As a result, the synthesized hydrogels showed good self-adhesion (3.12 KPa on the skin), great stretchability (>1700 %), and satisfactory electrical conductivity. These multifunctional hydrogels operated as adaptable sensors, adeptly capturing the nuanced signals emanating from an array of human motions. They exhibited an expansive strain tolerance, swift reactivity, and an enhanced acuity in detecting even the slightest deformations (GF = 2.1). Our research provides new insights for creating stretchable, self-adhesive, and functional hydrogels for sensing applications.