Highly sensitive strain sensor using silver nanowire/poly(3,4-ethylenedioxythiophene): Polystyrene sulfonate coated natural rubber

Abstract

Stretchable strain sensors have attracted much attention for health monitoring systems, human-machine interfaces, and robotics. However, there is still a challenge to develop strain sensors with excellent mechanical stretchability and high strain-sensing region as well as cost-effective fabrication process. Herein, a highly sensitive, reliable and low-cost strain sensors are developed using a resistive transduction of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and silver nanowire (Ag NW). Natural rubber was used as a stretchable substrate material, and a gold leaf was used as electrodes placed between PEDOT:PSS and Ag NW. The electrical resistance of this novel strain sensor shows an average value of 74.72 ± 14.65 Ω with a large sensing range up to 50% strain and sensing sensitivity of 418. The sensing response does not deteriorate after 750 stretching-releasing cycles and the sensor exhibits high stability after storage in air for more than 53 days. Concerning finger and joint movement, the wearable strain sensor demonstrates a stable output signal and distinguishes response under different bending and stretching. These advantages make it potential applications in wearable electronic devices and promising development in healthcare management.