Integrated core-shell structured smart textiles for active NO2 concentration and pressure monitoring

Energy crisis and atmospheric contamination urgently warrants the low-energy consumption and scalable hazardous gas detection for environmental government. However, most of existing gas sensors are restricted by tremendous power supply and burdensome maintenance as well as bulky volume. Herein, a core-shell structured smart textile (CST) was constructed via coaxial electrospinning to synchronously and sympatrically couple the piezoelectric transduction of polyvinylidene fluoride/lead zirconate titanate (PVDF/PZT) core layer and chemoresistor-sensing of polyaniline/polyvinyl pyrrolidone (PANI/PVP) shell layer in a single fiber, enabling autonomous and simultaneous monitoring of pressure and concentration of NO2 gas. The three basic gas sensing attributes of receptor function, transducer function and utility factor of the sensing body can be concurrently modulated/optimized by tuning the composition and mesoscopic configuration of porosity and sensing-transducing component ratio. A high sensitivity of 0.32 ppm(-1), low detection limit (similar to 100 ppb) and good selectivity was achieved toward NO2 detection. Furthermore, the as-prepared CST demonstrates great capability in simultaneous gas pressure (57 mV/KPa) and concentration detection. By combining theoretical modeling and numerical simulation, a sensing mechanism was established to well unravel/predict the gas sensing behaviors. This work opens a new paradigm for constructing active multifunctional environmental sensors and multimodal smart textiles.