Bioinspired anisotropic architectures in AgNWs/MFC/SA/PDMS composite aerogels for enhanced wearable piezoresistive sensors

A bioinspired honeycomb composite aerogel was fabricated by freeze-drying. • AgNWs-based conductive networks enabled stable piezoresistive sensing behavior. • PDMS impregnation improved mechanical stability and environmental resistance. • The composite elastomer exhibited antibacterial activity (∼95%). • Wearable sensors demonstrated high sensitivity, fast response and stable cycling. Wearable piezoresistive sensors show great potential for motion analysis, health monitoring, and human–computer interaction. However, conventional sensing materials often suffer from limited sensitivity, insufficient flexibility, poor environmental adaptability, and inadequate antibacterial performance for skin-contact applications. Herein, a bioinspired anisotropic AgNWs/MFC/SA composite aerogel (30 A-55MS) was fabricated by directional freeze-drying, using silver nanowires (AgNWs) as the conductive and antibacterial network, microfibrillated cellulose/sodium alginate (MFC/SA) as the biomass-derived polymer scaffold, and CaCl 2 as the ionic-gelation agent. The directional porous architecture was inspired by the transport-channel structure of taro stalks. Subsequently, polydimethylsiloxane (PDMS) was introduced by vacuum-assisted impregnation to obtain the 30 A-55MS/PDMS composite aerogel elastomer. PDMS encapsulation enhanced the mechanical stability and environmental resistance of the elastomer, which also exhibited bacterial reduction efficiencies of 95.57% against E. coli and 95.21% against S. aureus . The wearable piezoresistive sensor assembled from the 30 A-55MS/PDMS elastomer exhibited a high gauge factor (GF = −20.792 in the 0–2% strain range), rapid response/recovery times of 65/40 ms, and stable cycling performance over 1000 compression cycles. Moreover, real-time finger, neck, elbow, wrist, and knee movements were successfully monitored. This work provides a promising strategy for developing multifunctional aerogel-based wearable sensors for health monitoring, motion analysis, and human–computer interaction.