Porous\nCore–Shell Yarn in Wearable Electrochemical\nSensors for Real-Time Sweat Monitoring

Wearable\nsweat sensors have garnered substantial attention owing\nto their actual significance in the noninvasive and real-time monitoring\nof health conditions. However, it remains significantly challenging\nto efficiently construct a high-sensitivity sweat sensor with stable\nlong-term sensing capability. Herein, we report an effective methodology\nbased on wet-spinning/acid-etching technology to construct a porous\ncore–shell yarn-based wearable electrochemical sensor. This\nstrategy increases the inductive surface area of the ion concentration\nand facilitates signal transmission. As a result, the sensor demonstrates\nhigh sensitivity for monitoring K<sup>+</sup> and pH in sweat (54.89\nmV/dec for K<sup>+</sup> and 40.2 mV/pH for pH). Furthermore, the\nsensors exhibit outstanding sensing stability, good long-term stability\n(>16 h), and satisfactory bending resistance (>1000 cycles).\nMore\nimportantly, the sensing yarns could be prepared at speeds of up to\n500 m/h with a continuous preparation strategy, which enabled mass\nfabrication of the electrochemical sensor. Electrochemical sensors\ncould serve as sweat-sensing systems for real-time health monitoring\nand hold great potential for the commercialization of health-detection\ntechnology.