Stable Flexible Piezoresistive Sensors with Viscoelastic Ni Nanowires‐PDMS Composites and Ni Foam Electrodes

• Published in: Zeitschrift für anorganische und allgemeine Chemie (1950) 2021-05, Vol.647 (9), p.1031-1037
• Main Authors: Luan, Ruifei, An, Hang, Chen, Chen, Xue, Yu, Guo, Ailin, Chu, Liang, Ahmad, Waqar, Li, Xing'ao
• Format: Article
• Language: English
• Subjects: Adhesive strength; Bending; Blinking; Composite materials; electrode contact; Electrodes; Flexible piezoresistive sensors; Human motion; Metal foams; Modulus of elasticity; Nanowires; Ni foam electrodes; Ni nanowires; PDMS; Sensors; Viscoelasticity; Wearable technology; Wrist
• ISSN: 0044-2313; 1521-3749
• DOI: 10.1002/zaac.202100005

Flexible piezoresistive sensors with viscoelastic conductive free‐standing films have attracted tremendous interest for the great practical applications of human motion and health monitoring, and intelligent electronic skins. However, it is still a challenge to achieve stable and strong adhesion between the viscoelastic conductive films and two electrodes due to mismatched Young's modulus. Herein, the as‐prepared Ni nanowires were mixed with PDMS to form viscoelastic conductive composites, which were strongly contacted on and partly permeated into Ni foam electrodes for flexible strain sensors. Importantly, the binding between the viscoelastic conductive composites and Ni foams is strong and stable, which can be remained after a thousand forward and backward bent. The fabricated flexible piezoresistive sensors were utilized to monitor human motion including clicking mouse, finger bending, elbow bending, eye blinking and wrist bending. The typical respond and recovery times are fast to about 0.1 s. Thus, this sensor will have great potential for future real applications in smart wearable devices.