Self-Healing Soft Robotic Systems with Graphene and Graphene Oxide Based E-Skin

Soft robots, composed of compliant polymers and hydrogels, can safely interact with humans and fragile environments but remain vulnerable to cuts, punctures, and tears, which limit their service life. Self-healing polymers and hydrogels have therefore been proposed as sustainable solutions for soft robotics because they can recover their mechanical and functional properties after damage either autonomously or under mild external stimuli. In parallel, electronic skin (e-skin) platforms are required to endow robots with environmental perception; graphene- and graphene oxide (GO) based conductive, stretchable and self-healing materials have emerged as promising candidates for such skins. In this work, graphene- and GO-based self-healing e-skin systems for soft robotics are evaluated and compared. Polyurethane–GO networks can achieve tensile strengths in the range of 30–80 MPa and toughness values of 250–500 MJ m⁻³ while maintaining mechanical self-healing efficiencies of 80–90 % at room temperature. Photothermally triggered GO composites can further provide 88–99 % healing within 20–60 s under infrared irradiation. Graphene/GO-reinforced hydrogel and elastomer e-skins operate over wide strain ranges (300–850 % and above) and exhibit competitive gauge factors, response times and electrical healing efficiencies compared with state-of-the-art ionic and polymeric self-healing e-skins. Overall, the results indicate that graphene- and GO-based self-healing e-skins are strong candidates for endowing soft robots with both sensing and self-protection capabilities.