An energy efficient and sustainable approach to structural health monitoring in carbon fiber composites: harnessing sound-induced vibration with Ti3C2Tx MXene/AgNPs modified P(VDF-TrFE) sensors†

Abstract

The growing demand for high-strength, lightweight carbon fiber composites (CFCs) in various industrial sectors highlights the necessity of structural health monitoring (SHM) to prevent catastrophic failures. Accelerometers, as reliable battery-operated monitoring devices, face risks of exposure in harsh environments. Therefore, it is essential to explore a self-powered and highly sensitive alternative sensor. To address this necessity, flexible polymer-based piezoelectrics are gaining attention as self-powered sensors. However, improving their sensitivity in SHM remains a challenge. Here, nanofiber sensors made from a poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) copolymer modified with Ti₃C₂T_x MXene and silver nanoparticles (AgNPs) are fabricated through the electrospinning technique. The introduction of MXene and AgNPs (1 wt%) improves crystallinity by 23% and boosts output voltage nine times, while maintaining good flexibility in an all-fiber-based sensor structure. In an innovative approach, sound-induced vibrations are utilized to stimulate the mounted sensors on various thicknesses of CFCs for SHM. This approach outperforms conventional accelerometers in detecting three types of damage (longitudinal, transverse, and impact) over a frequency range of up to 1500 Hz. This strategy not only effectively harnesses environmental sound in an energy-efficient way but also demonstrates sensor sensitivity, highlighting its potential to advance smart sensing systems.