Highly Sensitive Pressure Sensor Based on Elastic Conductive Microspheres

• Published in: Sensors (Basel, Switzerland) Vol. 24; no. 5; p. 1640
• Main Authors: Li, Zhangling, Guan, Tong, Zhang, Wuxu, Liu, Jinyun, Xiang, Ziyin, Gao, Zhiyi, He, Jing, Ding, Jun, Bian, Baoru, Yi, Xiaohui, Wu, Yuanzhao, Liu, Yiwei, Shang, Jie, Li, Runwei
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 02-03-2024; MDPI
• Subjects: 3D printing; Carbon; Curing; elastic pressure sensor; Electrodes; electrostatic self-assembly; Environmental impact; Instrument industry; Laser etching; Leaves; Microscopy; Microstructure; MXene–SWCNT; PDMS conductive microspheres; Pressure regulators; R&D; Research & development; Sensors; Silicones; United States; China; United States > US; PDMS conductive microspheres; electrostatic self-assembly; MXene–SWCNT; elastic pressure sensor; 3D printing
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s24051640

Elastic pressure sensors play a crucial role in the digital economy, such as in health care systems and human-machine interfacing. However, the low sensitivity of these sensors restricts their further development and wider application prospects. This issue can be resolved by introducing microstructures in flexible pressure-sensitive materials as a common method to improve their sensitivity. However, complex processes limit such strategies. Herein, a cost-effective and simple process was developed for manufacturing surface microstructures of flexible pressure-sensitive films. The strategy involved the combination of MXene-single-walled carbon nanotubes (SWCNT) with mass-produced Polydimethylsiloxane (PDMS) microspheres to form advanced microstructures. Next, the conductive silica gel films with pitted microstructures were obtained through a 3D-printed mold as flexible electrodes, and assembled into flexible resistive pressure sensors. The sensor exhibited a sensitivity reaching 2.6 kPa
with a short response time of 56 ms and a detection limit of 5.1 Pa. The sensor also displayed good cyclic stability and time stability, offering promising features for human health monitoring applications.