Organohydrogel Strain Sensors with Low Mechanical Hysteresis and Adhesion for High‐Quality Signals

AbstractThe hysteresis of deformation and weak interaction between sensors and targets would deteriorate the authenticity and reliability of signals outputted from the strain sensors. Here, low‐hysteretic and adhesive organohydrogel‐based strain sensors (P‐H‐A‐A) are prepared according to the homogeneous growth of the conductive polyaniline (PANi) network and heterogeneous growth of the adhesive poly(acrylic acid) (PAA) layer from the poly(hydroxyethyl acrylate) (PHEA) seeds. Via regulating the concentration of aniline (ANi) in the ANi‐nutrients, the mechanical hysteresis at 50% strain of P‐H‐A‐A organohydrogels increased from 12 to 1896 kJ m−3. The relative resistance (ΔR/R0) signals achieved from the low mechanical hysteresis P‐H‐A‐A (0.1 m) strain sensors are timelier and more intact than the one from the obviously mechanical hysteretic P‐H‐A‐A (0.5 m). The PAA layer makes the P‐H‐A‐A strain sensors conformally in contact with the skin, ensuring the reliability and integrity of signals. This work would give some helpful suggestions for designing advanced epidermal electronics.