A Highly Sensitive Wearable Thermometer with MWCNT and PEDOT:PSS Composite

Temperature sensing is crucial for effective health monitoring, including infection detection, metabolism management, and heat exhaustion prevention. This study introduces a wearable thermometer that integrates PEDOT:PSS and MWCNT to enhance both mechanical stability and thermal sensitivity. It is first confirmed that incorporating MWCNT with PEDOT:PSS significantly improves deposition stability and thermal sensitivity. By optimizing the ratio of MWCNT to PEDOT:PSS, a nanocomposite with low initial resistance, high-temperature sensitivity, and improved deposition stability is obtained. This optimized nanocomposite exhibited an initial resistance 10.9 times lower and superior temperature sensitivity compared to MWCNT-only composites. The thermometer, fabricated using this optimized nanocomposite, underwent water-bath modeling experiments, achieving a temperature coefficient of resistance of 0.60 ± 0.07% °C⁻¹ and demonstrating a thermal resolution of 0.65 °C, indicating excellent performance. Finally, the fabricated thermometer is validated by testing it on various body locations, including the trapezius, armpits, and forearm. The performance of this thermometer is comparable to that of commercial laser thermometers, providing accurate temperature measurements across different body sites. These results suggest that PEDOT:PSS and MWCNT-based nanocomposite thermometer is a promising tool for continuous health monitoring and medical diagnostics when used in wearable applications.