Flexible devices have been rapidly developed and applied in various applications. However, there have been few reports on printable graphene-based sensors with customized structures and properties capable of respiratory and airflow monitoring. In this study, a graphene-based flexible sensor with a conical microdot array (GSCA) made by the direct-ink writing 3D printing method for real-time personal signals and air-coupled detection is reported. GSCA 3D structures with microdot features on the sensing layer can deliver a fast response of below 60 ms and improve the sensitivity by 32.4% (26–78 kPa), 800% (78–102 kPa), and 600% (102–160 kPa) by adjusting the printing parameters. The sensor exhibits a low detection limit of 11.4 Pa and a large detection range with a linear sensitivity of 1.4–509 kPa. The spider leg-like micro-/nanofibers between two adjacent microdots contribute to electron transport and airflow sensing. The results show the feasibility of the graphene-based sensor with dots to recognize air strength and direction for respiration and airflow. Further validation of the GSCA in real-time personal monitoring demonstrates the potential for multitasking wearable sensors.
Bibliographical noteFunding Information:
The authors sincerely acknowledge financial support from the National Natural Science Foundation of China (no. 81771960 to M.W.C.), the National Natural Science Foundation of China (no. 82172064 to X.C.), the Major Scientific Project of Zhejiang Lab (no. 2020MC0AD01 to X.C.), the National Key Research and Development Program of China (no. 2019YFC1711800 to J.L.), and the Pioneer Project of Zhejiang province (no. 2022c03188 to X.C.). Informed consent was obtained from all volunteers who participated in this study.
© 2023 American Chemical Society
- direct-ink writing
- wearable electronic