Tunable Sensitivity in PAN/CNF/PEDOT:PSS Nanofiber‐Based Piezocapacitive Sensors

ABSTRACT Flexible piezocapacitive pressure sensors are poised to underpin next‐generation wearable electronics; however, the concurrent attainment of high sensitivity, mechanical endurance, and structural tunability within a scalable fabrication framework remains a formidable challenge. Here, a class of robust and tunable capacitive pressure sensors engineered from electrospun polyacrylonitrile (PAN) nanofibers incorporating functional conductive fillers: carbon nanofibers (CNF) and poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is presented. Systematic optimization of filler composition and nanofiber mat thickness yields pronounced enhancements in electromechanical responsiveness. Notably, incorporation of 0.2 wt.% CNF and 2 wt.% PEDOT:PSS delivers sensitivities of 27 and 47 MPa −1 in the low‐pressure regime, representing improvements of 94% and 237% relative to pristine PAN, respectively. A clear thickness‐dependent behavior is observed, with ultrathin nanofiber mats (0.5 mL electrospun volume) consistently achieving the highest sensitivity through superior compressibility and dielectric modulation. Continuous loading reveals nonlinearities associated with air entrapment in the porous matrix, while cyclic testing over 2000 cycles confirms exceptional mechanical resilience with <3% signal degradation. These findings delineate a scalable strategy for the fabrication of robust, tunable, and sensitive pressure sensors, advancing their deployment in wearable biomedical monitoring and soft human–machine interfaces.