Highly sensitive and stretchable fiber strain sensors based on ITO NPs/CNTs composite

Flexible and multifunctional sensors are in demand in various fields, but achieving excellent sensitivity and an extensive operational range poses a challenge. Here, we developed a flexible strain sensor using a cost-effective dip-coating method, incorporating microcracked synergistic indium tin oxide nanoparticles (ITO NPs) and carbon nanotubes (CNTs) in a conductive layer. Utilizing an elastic rubber core string as the stretchable substrate and Thermoplastic polyurethane (TPU) as an interfacial modifier, we established connectivity between the substrate and conductive layer. After encapsulation with polydimethylsiloxane, the ITO NPs/CNTs/rubber fiber (ICRF) strain sensor was fabricated. This sensor demonstrates a broad sensing range (0 ∼ 300 %), remarkable sensitivity (GF=1033.57), swift response/recovery times (174.55 ms/180.27 ms), and exceptional durability and stability (>2000 cycles). Moreover, it proves effective for human motion detection, underscoring its potential in flexible and wearable devices. Finally, precise responses of the mechanical claw’s posture and grasping demonstrate its potential applications across multiple fields.