Wearable Piezoresistive Sensors with Enhanced Sensitivity via Click Chemistry-Constructed Multi-Convex Microfiber Surfaces

Highly sensitive flexible pressure sensors have garnered significant attention due to their applications in human motion monitoring, medical diagnostics, and human–computer interfaces. In this study, we present an innovative sensor design based on sea–island polyamide (PA) microfibers─a byproduct of the synthetic leather industry─as a flexible substrate, combined with carbon black (CB) and silver nanowires (AgNWs) as dual conductive components. Using thiol–ene click chemistry, a conductive CB nanoparticles as “multi-convex” microstructure was engineered on the PA surface, in which CB nanoparticles form the primary conductive network while AgNWs act as bridging connectors to establish multiple conductive pathways. The resulting PA/CB/AgNWs composite sensor demonstrates outstanding performance, including ultrahigh sensitivity (54.88 kPa –1 ), rapid response and recovery times (20 ms each), and a wide detection range (0.1–2.5 kPa), while maintaining excellent mechanical durability and breathability for wearable comfort. Its practical utility was verified through comprehensive body motion monitoring, capturing both large-scale joint movements (elbows, knees) and subtle physiological signals (facial expressions, vocal vibrations). This work offers a cost-effective strategy for fabricating high-performance wearable sensors and provides a promising platform for micromotion detection in healthcare and human–machine interaction applications.