A water-resistance and breathable fabric-based sensor with high sensitivity for air and underwater applications

A wearable sensing device, it not only has good breathability to ensure long-term wearing comfort but also needs to have waterproof ability to avoid sweat erosion. However, most reported works only have breathability or waterproof ability, which greatly limits their application. Herein, we designed and fabricated a water-resistant and breathable sensor based on non-woven fabric via the simple methods of 3D direct writing and spray coating. The sensing principle of supercapacitive and the micro uneven structure of fibers endows the sensor with high sensitivity (77.19 kPa−1), wide detection range (0–65 kPa), fast response speed (within 50 ms), cycle stability (over 10,000 cycles). The stearic acid (STA) coating method enables the sensor with excellent hydrophobicity (water contact angle of about 160.9°) and waterproof ability that can work normally in humid environments and even underwater. Benefiting from the natural micropore structure of fibers, the sensor demonstrates excellent air permeability (359.4 mm s−1). As a result, the fabric-based sensor can monitor human motions, and physiological signals and recognize gestures in the normal open-air and underwater environment, demonstrating its huge potential in underwater applications.