Highly breathable and sensitive iontronic wearable sensor based on porous ionic electrolyte and microstructure for human movement sensing
Peng Wang, Jinjing Cao, Yurui Li, Guifen Sun, Haiyan Shao, Chuizhou Meng
Abstract
Flexible sensors have received enormous attention for various potential applications in healthcare biomonitoring. However, achieving high sensitivity, wide sensing range, reliable breathability and hydrophobicity for long-term comfortable health monitoring remains a key challenge. Herein, we present a breathable and hydrophobic pressure sensor with high sensitivity and a wide detection range based on porous ionic electrolyte and nanofiber. The sensor consists of a middle porous ionic electrolyte, top and bottom micropatterned Ag/G/TPU nanofiber electrodes. Thanks to the microstructures and the supercapacitive working principle, the assembled electronic sensors exhibit ultra-high sensitivity (21.3 kPa −1 ), a wide working range (0.30–106 kPa), an extremely low detection limit (about 40 mg), and significant reliability. Benefits from the microporous structures in the electrode and electrolytes, the prepared sensor shows high air permeability (25.02 mm/s) and moisture permeability (102.35 g/m 2 h), improving long-term comfort wearing. Meanwhile, the hydrophobicity (155.1°) of TPU nanofibers endows the sensor with excellent sweat resistance. The fabricated sensor has been successfully applied in human movement recognition with a 100 % success rate with the help of a neural network. This work is expected to pave the way for the manufacture of breathable, hydrophobic, highly sensitive and wide-range pressure sensors in the next generation of electronic skin.