A Sodium Titanate-Based Flexible Sensor with Accurate Human Motion Perception and Dyeability

Flexible conductive sensing materials are widely used in wearable electronics, smart textiles, and biomedical monitoring. Conventional dark-colored, poorly dyeable materials (e.g., carbon-based, polyaniline-based) limit their applicability, thus driving the demand for high-performance, light-colored, dyeable alternatives. Herein, light-colored ATO@Na₂Ti₆O₁₃/PU fibers/films were fabricated via wet spinning/electrospinning, respectively, while Na₂Ti₆O₁₃ whiskers serving as TiO₂ intermediates were synthesized via one-step calcination of 25 nm TiO₂ with NaCl/Na₂CO₃ at a mass ratio of 4:8:1, which reduced costs and simplified fabrication procedures. The prepared ATO@Na₂Ti₆O₁₃/PU fibers/films show light color (max whiteness 85)and excellent dyeability and color fastness (rubbing ≥ grade 3; washing ≥ grade 4, ISO standards), resolving the functionality-aesthetics trade-off. The conductive fibers with 20 wt % conductive filler combined electrical conductivity (∼903.5 Ω·cm), mechanical properties (∼3500 kPa breaking stress, ∼410% elongation at break), rapid response/recovery times (0.3 s/0.3 s), and cyclic stability (cycling for 4000 s under 250% strain). When integrated into wearable sensors, they can accurately capture human movements, finger motions, and throat muscle stretching during vocalization.