Flexible Porous Pomelo Pith Derived Janus Liquid Metal and Adhesive Hydrogel Hybrid Electronic Skins

Abstract

Liquid metal (LM)-derived electronic skin (e-skin) exhibits significant potential in the domains of human-machine interfaces, health monitoring and energy management. Herein, we introduce a cost-effective paradigm of LMs-derived e-skin featuring anti-freezing capability, efficient thermal management, and motion detection. The inexpensive and eco-friendly porous pomelo pith (PP) is employed as the substrate for the patterning of LM and as the physical scaffold for adhesive hydrogels. The unique porous architecture of the PP provides a natural template for the integration of LM and hydrogels, which facilitates the creation of electronic devices with improved flexibility and adhesion. The diverse patterning of nickel (Ni)-doped LM on the rough and porous pomelo pith surface is facilitated by the attractive force of a magnetic field applied below. The adhesive pre-gel is readily drawn into the pores of the pomelo pith due to capillary action. The resulting LM/PP hydrogel electronics are capable of rapid and stable Joule heating behavior and reliable motion detection. Additionally, the incorporation of glycerol endows this e-skin with superior freezing and desiccation resistance. Thus, this facile fabrication strategy successfully integrates excellent conductivity, adhesion, and environmental resilience, offering a promising paradigm for advanced wearable electronics.

Keywords

adhesive / electronic skin / hydrogel / liquid metal / pomelo pith

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2026 The Author(s). Smart Medicine published by Wiley-VCH GmbH on behalf of Wenzhou Institute, University of Chinese Academy of Sciences.