A high‐performance stretchable strain sensors with hierarchically gradient morphology of filler network

Abstract

In recent years, stretchable strain sensors have received increasing attention in areas such as human motion detection and soft robotics. However, how to simultaneously improve the sensitivity and operating range of them remains one of the most important challenges. In order to solve this challenge, in this study, nickel‐coated graphite (NCG)/carbon nanotubes (CNTs) hybrid conductive networks of stretchable strain sensors PNCs with graded degree of sedimentation were constructed in PDMS using the sedimentation method. Due to the difference in packing density and packing morphology, NCG mainly stays in the middle and lower layers, forming a partially‐sedimented state, whereas the CNTs are close to uniformly dispersed, and such partially settled NCG network is especially critical. Based on this, the obtained composite PNCs have high sensitivity, with a GF value as high as 1.48 × 104 in the 0%–25% strain range and an operating range of 224.8%, which achieves a good recognition and detection of the full range of human body movements. This work provides a new process for the preparation of high‐performance stretchable strain sensors.