Bioinspired waterproof and self-healing Photonic-Ionic skin for underwater interactive sensing

Bioinspired photonic-ionic skins (PI-skins) possessing multiple signals considerably promote the development of soft ionoelectronics owing to the fascinating interactive sensing capabilities. Unfortunately, swelling and leakage in aqueous environments are significantly detrimental to the stability and durability of underwater sensing. Herein, a novel PI-skin with waterproof, self-healing, and highly resilient properties is ingeniously fabricated via integrating the photonic array and dynamically covalently crosslinking fluorine-rich ionogel. Benefiting from the strain-modulated nanostructure and ionic conduction, the PI-skin achieves unique dual-signal sensing capability with sensitive mechanochromic performance and synchronous electrical response. Furthermore, the synergistic water repellency of the trifluoromethyl on the skeleton and the long alkyl chain modified hydrophobic ionic liquid (IL) inhibit swelling and leakage, significantly enhancing underwater stability. Notably, the exchangeable hindered urea bonds (HUBs) were judiciously introduced to construct a stable dynamically covalently cross- linking network, achieving efficient self-healing and high resilience simultaneously. The PI-skin with excellent adhesion and durability demonstrates the application potential in dual-signal underwater sensing and wireless information transmission. This work offers innovative design inspirations for the advancement of multifunctional artificial skins, intelligent interactive devices, and high-performance wearable iontronics.