V2O5 Nanowires-Coated Yarn-Based Temperature Sensor With Wireless Data Transfer for Smart Textiles

Smart textiles with capabilities to sense different stimuli like temperature and pressure are of considerable interest in applications such as sports, fashion, healthcare, and robotics. The seamless integration of various sensors is desired for the effective use of smart textiles in these applications. To this end, here, we present a yarn-based wireless temperature sensor developed by modifying a polyvinylidene fluoride trifluoroethylene [P(VDF-TrFE)]-coated stainless steel yarn with vanadium pentoxide (V
₂
O
₅
) nanowires (NWs). The current–voltage (
$I$
–
$V$
) characteristics and the temperature sensing performance of the devices are evaluated between 5 °C and 50 °C with a step increase of 5 °C. The unpacked device exhibits a sensitivity of 3.7%/°C with a response time of 9 s. The device is encapsulated with a nanosilica/epoxy polymeric layer and its influence on sensors performance is also analyzed. After encapsulation, the device showed a more linear response, but with a slightly reduced sensitivity of 2.18%/°C. Moreover, the effect of mechanical bending cycles on the sensing performance of the packaged device is studied. The sensor showed a linear response even after 2000 bending cycles, but sensitivity was reduced to 1.257%/°C. Finally, the temperature sensor data is wirelessly transferred to demonstrate the potential use of developed sensors in the above applications.