Bioinspired wet-resistant organogel for highly sensitive mechanical perception

Abstract

Smart flexible electronics with underwater motion detection have become a promising research aspect in intelligent perception. Inspired by the strong adaptability of marine creatures to complex underwater environments, conventional biocompatible hydrogels are worth developing into organogels with preferred underwater adhesive properties, hydrophobic and antiswelling performance, and motion perception ability. Herein, a highly sensitive organogel sensor exhibiting good hydrophobicity, electromechanical properties, and adhesion properties was prepared for underwater utilization by regulating the chemical components and internal interactions. The synergistic effect of massive reversible non-covalent bonds ensures the organogel’s excellent underwater adhesion to multifarious substrates. Meanwhile, the interactions of hydrophobic conductive fillers and the dynamic hydrophobic associations in the organogel endow it with satisfactory hydrophobic performance (contact angle of 111.8°) and antiswelling property (equilibrium swelling ratio of −31% after 15-day immersion). The fabricated flexible organogel strain sensor exhibits high sensitivity (gauge factor of 1.96), ultrafast response rate (79.1 ms), low limit of detection (0.45 Pa), and excellent cyclic stability (1044 tensile cycles followed by 3981 compressive cycles). Results demonstrate the proposed organogel’s precise perception of sophisticated human motions in air and underwater, which expands its application scenarios.