Nanoarchitectonics of high-sensitivity humidity sensors based on graphene oxide films for respiratory monitoring

• Published in: Diamond and related materials Vol. 144; p. 110970
• Main Authors: Wang, Chenxue, Cui, Ziyang, Zhu, Yangyang, Liu, Xin, Wang, Lu, Wang, Li Juan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2024
• Subjects: Graphene oxide; Humidity sensors; Respiratory monitoring; Graphene oxide; Respiratory monitoring; Humidity sensors
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2024.110970

Respiration monitoring is important for assessing human health, but most sensors have complex structures and processes. In this paper, the response of graphene oxide (GO) sensors with bottom- and top-connected structure to humidity is investigated for respiratory monitoring. The sensors of the bottom-connected structure increase the current by 132.97 % and 2077.55 % compared to those of the top-connected structure at GO concentrations of 25 mg/ml and 50 mg/ml, respectively. Both types of sensors can achieve corresponding responses to humidity (40 %–80 % relative humidity (RH)). The bottom-connected sensors, however, exhibit better performances with the responsivity of 96.25 % at 80 % RH and the sensitivity of 131.33 %/RH. In real-time monitoring for humidity, the bottom-connected sensors have good repeatability. The sensors can distinguish different breathing modes and detect the respiration rate/depth of the target. This provides an important method for the development of simple and fast humidity sensors. [Display omitted] •Graphene oxide humidity sensors with bottom- and top- connected structure were prepared by spin-coating method.•The response of sensors with bottom- and top- connected structures increases with increasing humidity.•Sensors with bottom-connected structure were a higher current than those with top-connected structure.•Sensors with bottom-connected structure have the responsivity of 96.73 % at 80 % RH and the sensitivity of 153.10 %/RH.•Sensors with bottom-connected structure have good repeatability in real-time monitoring for humidity.