Development of a Fiber-Shaped MLPerovskite Sensor for Structural Health Monitoring in Composites

Abstract

Composite materials are widely used in various industries due to their high strengthto- weight ratio and appealing properties. However, the detection and assessment of damage in composite structures can be challenging, requiring the use of effective structural health monitoring (SHM) techniques. This study explored the potential of an embedded fiber-shaped mechanoluminescence (ML)-perovskite sensor for real-time monitoring of impact events in composites. The sensor was fabricated by coating a perovskite photodetector with a sensing layer comprising copper-doped zinc sulfide (ZnS:Cu)/polydimethylsiloxane (PDMS) blend, using carbon nanotube (CNT) yarns as a substrate. The sensor was characterized and its ability to detect low-energy impact events, which is an important indicator of SHM, was assessed. ML materials emit light when subjected to mechanical stress, which can be detected by a perovskite photodetector and converted to an electrical current. The variations in the electrical current can be measured to provide in-situ and real-time information on the condition of the structure. CNT yarns are a suitable candidate for embedded sensors in composite structures due to their high sensitivity and exceptional mechanical properties. The flexibility of the CNT also allows the sensor to be weaved within a composite fabric, minimizing the intrusiveness effect of the embedment process. The experimental result showed that the CNT ML-perovskite sensor demonstrated good sensitivity and response time to mechanical stimuli, and a direct correlation was observed between the intensity of the electrical current and the impact energy. The ML-perovskite device showed the potential as a promising embedded sensor for impact monitoring, which could significantly contribute to the field of SHM.