Recycling of Flyash: Route toward high-performance, eco-friendly, and cost-effective flexible strain sensor via synergizing multi-walled carbon nanotubes

Along with the widespread utilization of wearable and portable electronics, the rise of sensitive flexible strain sensors with wide detection range, excellent stability and affordable costs emerges as a substantial crux of this domain. Herein, we present a convenient and scalable approach for constructing high-performance flexible piezoresistive strain sensor by rationally assembling Flyash/Multi-carbon nanotubes (MWCNTs) active sensing hybrids. Owing to the unique heterostructure of Flyash/MWCNTs wherein Flyash is anchored with MWCNTs via polydopamine, the active sensing hybrids accommodated by porous polyurethane enables a sophisticated conductive network and large tensile deformability, permitting outstanding gauge factor of 1379, wide strain detection range of 0-100 %, remarkable operation stability and durability. Furthermore, the feasibility of sensor in human motions monitoring is validated. For the first time, the synergy of Flyash and MWCNTs demonstrates effective in advancing the sensing performance of piezoresistive strain sensor, providing a new sight towards high-performance, eco-friendly, and cost-effective flexible strain sensor.