A self-healing e-skin for quadruple-modal sensing

E-skins capable of multimodal perception are essential for intelligent human-machine interaction, yet integrating real-time responsiveness with structural self-healing across multiple sensing modalities remains a significant challenge. Here, we report a biologically inspired, self-healing e-skin that enables the perception of tactile, pressure, nociceptive, and thermal stimuli. The device adopts a vertically stacked compact architecture comprising double-network cross-linked polymer layers and eutectic liquid metal layers, enabling rapid and complete structural healing even after severe mechanical damage over a wide temperature range. We demonstrate that the e-skin retains its functional integrity after healing, with triboelectric and capacitive sensing units enabling high-sensitivity, spatiotemporally resolved tracking of tactile and pressure stimuli, respectively. Meanwhile, by quantitatively analyzing the mechanoluminescent and thermochromic spectra, the optical waveguide sensing units enable real-time optical encoding of nociceptive and thermal stimuli, thereby allowing effective classification of impact and burn injury risks. Our work lays a solid foundation for the development of intelligent robotic systems capable of adaptive perception and injury prevention in complex and dynamic human-machine environments.