Wet‐Adaptive Electronic Skin

Abstract Skin electronics provides remarkable opportunities for non‐invasive and long‐term monitoring of a wide variety of biophysical and physiological signals that are closely related to health, medicine, and human‐machine interactions. Nevertheless, conventional skin electronics fabricated on elastic thin films are difficult to adapt to the wet microenvironments of the skin: Elastic thin films are non‐permeable, which block the skin perspiration; Elastic thin films are difficult to adhere to wet skin; Most skin electronics are difficult to work underwater. Here, a Wet‐Adaptive Electronic Skin (WADE‐skin) is reported, which consists of a next‐to‐skin wet‐adhesive fibrous layer, a next‐to‐air waterproof fibrous layer, and a stretchable and permeable liquid metal electrode layer. While the electronic functionality is determined by the electrode design, this WADE‐skin simultaneously offers superb stretchability, wet adhesion, permeability, biocompatibility, and waterproof property. The WADE‐skin can rapidly adhere to human skin after contact for a few seconds and stably maintain the adhesion over weeks even under wet conditions, without showing any negative effect to the skin health. The use of WADE‐skin is demonstrated for the stable recording of electrocardiogram during intensive sweating as well as underwater activities, and as the strain sensor for the underwater operation of virtual reality‐mediated human‐machine interactions.