Magnetically induced micropillar arrays for an ultrasensitive flexible sensor with a wireless recharging system

• Published in: Science China materials Vol. 64; no. 8; pp. 1977 - 1988
• Main Authors: Gao, Libo, Han, Ying, Surjadi, James Utama, Cao, Ke, Zhou, Wenzhao, Xu, Hongcheng, Hu, Xinkang, Wang, Mingzhi, Fan, Kangqi, Wang, Yuejiao, Wang, Weidong, Espinosa, Horacio D.
• Format: Journal Article
• Language: English
• Published: Beijing Science China Press 01.08.2021; Springer Nature B.V
• Subjects: Chemistry and Materials Science; Chemistry/Food Science; Coils; Elastomers; Flexible components; Magnetic properties; Materials Science; Matrix materials; Morphology; Pressure sensors; Recharging; Response time; Sensitivity enhancement; Sensor arrays; Sensors; pressure sensor; flexible electronics; high sensitivity; supercapacitor; wireless recharging
• ISSN: 2095-8226; 2199-4501
• DOI: 10.1007/s40843-020-1637-9

Significant efforts have been devoted to enhancing the sensitivity and working range of flexible pressure sensors to improve the precise measurement of subtle variations in pressure over a wide detection spectrum. However, achieving sensitivities exceeding 1000 kPa −1 while maintaining a pressure working range over 100 kPa is still challenging because of the limited intrinsic properties of soft matrix materials. Here, we report a magnetic field-induced porous elastomer with micropillar arrays (MPAs) as sensing materials and a well-patterned nickel fabric as an electrode. The developed sensor exhibits an ultrahigh sensitivity of 10,268 kPa −1 (0.6–170 kPa) with a minimum detection pressure of 0.25 Pa and a fast response time of 3 ms because of the unique structure of the MPAs and the textured morphology of the electrode. The porous elastomer provides an extended working range of up to 500 kPa with long-time durability. The sophisticated sensor system coupled with an integrated wireless recharging system comprising a flexible supercapacitor and inductive coils for transmission achieves excellent performance. Thus, a diverse range of practical applications requiring a low-to-high pressure range sensing can be developed. Our strategy, which combines a microstructured high-performance sensor device with a wireless recharging system, provides a basis for creating next-generation flexible electronics.