Fruit Peel-Inspired Super-Stable Ionic Organohydrogel Electronics with Dense Hydrophobic Skin

Abstract

Hydrogels are easily dehydrated during use and storage, making it difficult to maintain structural and performance stability, which greatly reduces their application value as wearable devices. Inspired by the structure of fruit, an ionic organohydrogel core containing Ca2+ and glycerol was first fabricated, and then, stearic acid (STA) was rivetted on the organohydrogel surface through (3-aminopropyl) triethoxysilane to obtain a dense hydrophobic coating (100 μm). The organohydrogel with hydrophobic skin presented better water spreading resistance and mechanical strength. In addition to the moisturizing effect of Ca2+ and glycerol, the skin also further blocks the contact between the organohydrogel and the air, thereby significantly enhancing the anti-dryness of the organohydrogel. Therefore, this organohydrogel has extremely outstanding structural, strength, and electrical conductivity stability. The developed strain sensor based on this organohydrogel can realize human motion monitoring capability at ultra-low temperature. This design idea, which combines multiple anti-drying mechanisms, has great expansion value for other gels suitable for various application scenarios.