Fast response, gas-permeable flexible humidity sensor based on PEDOT:PSS-GO for respiration monitoring

With the development of the internet of things technology, sensors have played an important role in aerospace, industry, agriculture, medical and other fields. Especially in the aspect of wearable respiratory monitoring, real-time monitoring of multiple respiratory physiological parameters through intelligent sensors enable people to achieve early prevention and timely diagnosis of respiratory diseases. However, most of the humidity sensors have the disadvantages of poor permeability, long response time and narrow detection range. Therefore, this paper introduced a flexible humidity sensor with a wide detection range and fast response time for respiratory monitoring. The sensor used PEDOT:PSS-GO composite material as humidity sensitive material. Due to the addition of GO, the sensor had a wide linear detection range of humidity (35–80%RH) and a short response/recovery time (0.53/0.8 s). Moreover, the sensor used the micromesh structure of PI as the substrate, which had better flexibility and permeability and the sensor was easy to attach to complex surfaces such as masks or human skin. Based on these excellent sensing characteristics, the humidity sensor was connected with a miniature wireless communication component for human respiratory detection. The humidity sensor can clearly show the difference between normal and abnormal respiratory signals and this provided a new idea for the intelligent healthcare technology.