Homogenous Organohydrogel Mediated by Covalently-Converted Graphene Nanosheets as an Electronic Epidermis for Multimodal Perception and Soft Actuation

Abstract

Bioelectronics based on regular hydrogels containing conductive components severely suffer from inferior structural compatibility, impaired signal accuracy, and fatigue failure under harsh environments, thus constraining their multifunctionalities. To address the issues of additive agglomeration and phase separation within the polymer matrix, assembly of amphiphilic nanosheets at oil/water interfaces for costabilization is innovatively proposed. The critically dispersed graphene nanosheets, assisted by ionic liquid (IL) graft-exfoliation, can be chemically integrated into swelling-resistant polymeric networks through ultrasonic-induced gelation. Additionally, the synergistic effect between dimethyl sulfoxide (DMSO)/H₂O binary solvents and charged polar terminal groups weakens the hydrogen bonding within water molecules, enabling the organohydrogel with reliable environmental tolerance and long-lasting moisture retention. Owing to its high mechanical stretchability, satisfactory sensitivity, and exceptional photothermal conversion behavior, the fast prepared organohydrogel is fabricated into an all-climate wearable sensor for daily activities detection and temperature sensing, which lays the groundwork for human–machine interaction and thermosensation-based actuation.