Biomass-derived carbon nanospheres/PEDOT:PSS reinforced polyvinyl alcohol microdome hydrogel film for flexible piezoresistive sensing

Flexible pressure sensors featuring high sensitivity, broad sensing range, and excellent mechanical stability are core components for electronic skin and intelligent human machine interaction. Herein, coupling material synergistic effect and microstructure design, we fabricated a bio based flexible piezoresistive sensor via a facile molding process. The sensor adopts a micro dome structured composite hydrogel film, using poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and squid ink-derived carbon nanospheres (CNPs) as hybrid conductive fillers, polyvinyl alcohol (PVA) as the matrix, and glycerol as the plasticizer. Benefiting from the dual enhancement of the synergistic conductive network and stress concentration effect induced, the sensor achieves a sensitivity of 44.09 kPa −1 , a sensing range of 0–123 kPa, a fast response/recovery time of 88 ms, and excellent cycling stability over 7000 cycles, along with favorable electrical conductivity and mechanical robustness.The sensor accurately captures dynamic pressure signals, showing promising application potential in Morse code recognition, handwritten letters, and human motion monitoring. Combined with a support vector machine (SVM) model, it reaches a 98.28% test set classification accuracy for five motion states. This work provides a novel strategy for green and low cost of high performance flexible piezoresistive sensors for wearable electronics. Download: Download high-res image (251KB) Download: Download full-size image