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Hydrogels have emerged as a landmark soft material for a wide range of applications such as in biomedical devices, soft robotics, artificial electronic skins, and the Internet of Things (IoT). To date, engineering hydrogels that simultaneously possess high stretchability (>3000%) and strong on-skin adhesion (>30 kPa) has not been an easy task. Generally, good stretchability is mainly dominated by the bulk interactions of hydrogels, whereas robust adhesion relies on the interfacial interactions of hydrogels with their surroundings. Here, we report a facile strategy to engineer an ultra-stretchable, highly adhesive and self-healable hydrogel, by virtue of tannic-acid-enabled dynamic interactions (TEDI) to fully substitute conventional covalent crosslinking. The TEDI strategy allows us to synchronously regulate both bulk and interfacial interactions to obtain exciting properties that outperform conventional hydrogels, including an extraordinary stretchability of over 7300%, remarkable self-healing abilities, and a robust on-skin adhesion of 50 kPa. With these intriguing merits, TEDI hydrogels are demonstrated to be a wearable strain sensor that accurately detect the motion of the human body. Moreover, our TEDI strategy unlocks new opportunities to design next-generation ionic hydrogels that may be valuable for applications in wearable electronic devices and healthcare monitoring.

Solar anti-icing/deicing (SADI) is an economically-efficient method of harvesting solar energy as heat for melting and removing ice. However, SADI materials with superior sunlight harvesting performances and high deicing rate remain elusive. Herein, the successful preparation of hierarchically macro/micro-structured polydimethylsiloxane (PDMS)/reduced graphene oxide (rGO) films was demonstrated based on a facile dual-template method. The as-fabricated films exhibited efficient broadband solar light absorption and high energy transfer efficiency (90.4%). When used as anti-icing/deicing materials, these SADI films exhibited excellent anti-icing/deicing performances under one sun illumination (qi= 1.0 kW m−2), i.e., long freezing delay time (tD> 2 h) and ultra-low deicing strength (∼0.2 kPa) even at an ultra-low temperature of −40 °C. The SADI surfaces showed a high deicing rate (>1.05 kg m−2h−1) under various simulated realistic conditions over a wide range of geographical differences. Moreover, all the frost, rime, and glaze (ice thickness < 2 mm) could be easily removed within 300 s.