Fabrication of a Superhydrophobic Conductive Porous Film with Water-Resistance for Wearable Sensors

Abstract

Stretchable strain sensors have promising applications in flexible electronics field, such as artificial skin, health monitoring, and smart wearables. However, their anti-corrosion property, outstanding sensitivity, and environmental adaptability of strain sensors still remain a great challenge. Herein, a porous film was constructed by coating the stack of conductive fiber network with a 1H,1H,2H,2H-perfluorodecyltriethoxysilane array via molecular self-assembly, which formed a superhydrophobic surface on the conductive film. The conductive porous film demonstrated the superior water-resistance interface with a water contact angle of 179.5° and favorable conductive stability in humid environments. In addition, the film can also exhibit a strain sensitivity in the wide range of 0–100%, a rapid response of 150–200 ms, and excellent stability. Meanwhile, the superhydrophobic surface has made droplets easier to slip off its surface during stretching, and the fog also has rapidly coalesced into droplets on the film. The outstanding superhydrophobic surface was attributed to the stable sensing performance under the sweat condition, showing great potential in wearable sensors of stretchable, breathable, and water-resistant for human behavior monitoring.

Pursuing Superhydrophobic Flexible Strain Sensors: From Design to Applications

“…This allows for precise monitoring of an individual's physical condition and significantly reduces the risk of accidents. [166] Stretchable strain sensors have demonstrated applicability in small strain motions, such as phonetic recognition and the detection of emotional expressions. [23,65,82] The sensor can be mounted on the neck to recognize vocalizations, thereby enabling a range of sound discernment, even in extremely noisy environments.…”

Durable superhydrophobic surface in wearable sensors: From nature to application

“…The incorporation of superhydrophobic technology can introduce additional protective layers, enhancing the durability of these electronic materials in harsh environments. [28,36] Flexible superhydrophobic thin films can be based on a variety of substrates, including metals, [120] silicon-based thermoplastic elastomers, [116] and thermosetting elastomers. [121] Such substrates are typically thin, stretchable, and flexible, making them suitable for adapting to complex or irregular surfaces.…”

“…Reproduced with permission. [ 28 ] Copyright 2023, American Chemical Society. (ii) Humid‐resistance self‐powered TENG sensors.…”

“…Wearable sensors with superhydrophobicity can significantly reduce the risk of short circuits when working in conductive solutions. [28] Ni and colleagues also reported the significance of corrosion resistance of wearable sensor surfaces in deep-sea environments, because it can significantly increase the corrosion resistance of equipment used for underwater operations. [29] This strategy is inspired by the fascinating bioinspired phenomenon known as the lotus effect, named after the behavior of liquid droplets that effortlessly roll on the surface of a lotus leaf.…”

“…Wearable sensors with superhydrophobicity can significantly reduce the risk of short circuits when working in conductive solutions. [ 28 ] Ni and colleagues also reported the significance of corrosion resistance of wearable sensor surfaces in deep‐sea environments, because it can significantly increase the corrosion resistance of equipment used for underwater operations. [ 29 ]…”