Wearable Temperature Sensor with High Resolution for Skin Temperature Monitoring

Flexible temperature sensors with high resolution and good reliability under deformation are a major research focus for wearable electronic devices for skin temperature monitoring. In this study, a fiber-like temperature sensor is fabricated by in situ growing poly(3,4-ethylenedioxythiophene) (PEDOT) on the surface of thermoplastic polyurethane (TPU) fiber. The temperature sensor achieves a high sensitivity of 0.95%·°C–1 with a high linearity between 20 and 40 °C. Most importantly, the sensor achieves a high temperature resolution of 0.2 °C. Due to its structure, the temperature-sensitive fiber is easily embedded into textiles. By sewing the fiber into normal textiles in an S-shape, the interference of strain can be nearly avoided, even when the textile is stretched to 140%. Also, the obtained sensors can monitor skin temperature during exercise, which demonstrates the potential of the sensor’s application in healthcare and disease diagnosis.