Printed Low-Hysteresis Stretchable Strain Sensor Based on a Self-Segregating Conductive Composite
Ayako Yoshida, Yifei Wang, Tomohito Sekine, Yasunori Takeda, Daisuke Kumaki, Shizuo Tokito
Abstract
The hysteresis of stretchable composites raises significant challenges in the accuracy, reliability, and stability of stretchable strain sensors. Herein, we report a self-segregating conductive composite that overcomes these issues in printed stretchable strain sensors. This printable composite possesses self-segregation between polydimethylsiloxane and carbon black, which was induced by a deep eutectic solvent. Compared with that of the conventional composites with a random conductive network, our spontaneously formed conductive architecture exhibits superior electromechanical performance: (i) low hysteresis and high sensitivity, (ii) high conductivity and low elastic modulus, and (iii) excellent reliability and stability. Moreover, the composite can be applied directly to a simple stencil printing process without any complex ink synthesis and post-treatment of the fabricated device. This work provides a materials design strategy for achieving low mechanical and electrical hysteresis in a conductive composite. The fabricated sensors exhibit comprehensive performance capabilities appropriate for whole body human motion detection as a proof of concept.