All-in-one fibrous capacitive humidity sensor for human breath monitoring

Abstract

Accurate and quick monitoring of an individual's respiration signals plays an important role in health monitoring and disease diagnosis. Electronic fabrics are the best candidates for detecting human signals through a non-invasive pathway. Inspired by the potential and attractive applications of fiber-shape electronics in smart and wearable e-textiles, here we developed an all-in-one fibrous capacitive humidity sensor. The fibrous sensor is prepared using a domestic winding fabrication facility and sputtering technique. Analysis of the exact morphology and elemental details of the fibrous sensor was carried out by Fourier transform infrared spectrometry, scanning electron microscopy, and energy dispersive spectrometry. Moreover, the frequency characteristic of the sensor is studied, and exhibits an increasing sensitivity with the decrease of testing frequency. The fabricated humidity sensor exhibited good repeatability and responsiveness performance under the 5 kHz frequency. In addition, the fibrous structure of the sensor makes it appropriate to be integrated into a fabric such as smart mask, which can be used to monitor breathing information and also to provide alarm signals.