Superhydrophobic Dual‐Layer Conductive Skin With Stable Sensing Properties in Air and Underwater

ABSTRACT Flexible strain sensors, crucial for wearable electronics and personal health monitoring, are often hampered by their vulnerability to moisture, contamination, and mechanical wear, which drastically degrades their performance in real‐world environments. While superhydrophobic coatings offer a potential solution, achieving a harmonious integration of high sensitivity, robust durability, and sustained superhydrophobicity under dynamic deformation remains a significant challenge. Here, we report a dual‐layer superhydrophobic conductive skin (SDCS) fabricated on a textile via sequential dip‐coating and spraying. The SDCS comprises a MXene‒chitosan conductive base and a fluorinated carbon nanotube/carbon black overlayer, forming a hierarchical structure that confers exceptional water repellency and mechanical robustness, maintaining functionality after extensive abrasion, stretching, and chemical exposure. This sensor exhibits a broad strain sensing range (112%), a gauge factor that increases with strain (361.34), and rapid response (142 ms). Its key advantage is operational stability in diverse environments—air, underwater, and when contaminated—where it resists fouling and displays self‐cleaning. We demonstrate practical utility through high‐fidelity monitoring of human motion, from muscle contractions to locomotion, and establish its potential for underwater communication via Morse code generated by finger gestures. This work provides a robust platform for wearable sensing in complex conditions.