Porous Core–Shell Yarn in Wearable Electrochemical Sensors for Real-Time Sweat Monitoring

Wearable sweat sensors have garnered substantial attention owing to their actual significance in the noninvasive and real-time monitoring of health conditions. However, it remains significantly challenging to efficiently construct a high-sensitivity sweat sensor with stable long-term sensing capability. Herein, we report an effective methodology based on wet-spinning/acid-etching technology to construct a porous core–shell yarn-based wearable electrochemical sensor. This strategy increases the inductive surface area of the ion concentration and facilitates signal transmission. As a result, the sensor demonstrates high sensitivity for monitoring K+ and pH in sweat (54.89 mV/dec for K+ and 40.2 mV/pH for pH). Furthermore, the sensors exhibit outstanding sensing stability, good long-term stability (>16 h), and satisfactory bending resistance (>1000 cycles). More importantly, the sensing yarns could be prepared at speeds of up to 500 m/h with a continuous preparation strategy, which enabled mass fabrication of the electrochemical sensor. Electrochemical sensors could serve as sweat-sensing systems for real-time health monitoring and hold great potential for the commercialization of health-detection technology.