High sensitivity and excellent durability of wearable microenvironmental humidity sensors inspired by the spider-web

In this study, we report a high-performance microenvironmental humidity sensor inspired by a spider-web structure, where a carbon nanotube network with cellulose nodes is constructed on the surface of cotton fabric by micro-dissolution technology. The obtained MWCNTs/cotton fabrics, as wearable humidity sensors, show excellent sensitivity when compared to other cotton fabric-based humidity sensors (maximum response of 99.6 %). In addition, the cellulose interlocking structure between the spider-web humidity-sensitive layer and the cotton substrate, provides the sensor with a strong interfacial adhesion. The sensor exhibits excellent durability (50 times cycling, 500 times folding, 20 times friction and stability over 3 months). As a theoretical validation, we simulated baby nappy moisture detection. The sensor shows significantly higher sensitivity and accuracy than commercial hygrometers and nappy discoloration strips, indicating that our sensor has great potential for humidity detection and early warning in body-worn microenvironments.