Water-resistant carbon nanotube based strain sensor for monitoring structural integrity

TL;DR

This paper presents a water-resistant, highly stretchable strain sensor based on creased carbon nanotubes encapsulated in a superhydrophobic coating, suitable for monitoring structural integrity in harsh environments.

Contribution

The authors developed a durable, water-resistant strain sensor using creased SWCNTs and a non-fluorinated superhydrophobic coating, enhancing robustness for structural health monitoring.

Findings

Sensor exhibits high linearity under elastic deformation

Water resistance maintained during operation

Scalable fabrication for infrastructure applications

Abstract

Monitoring structural integrity during and after extreme events such as an earthquake or a tsunami is a mundane yet important task that still awaits a workable solution. Currently available stress sensors are not sufficiently robust and are affected by humidity. Insufficient information about crack formation preceding structural failure increases risk during rescue operations significantly. Designing durable stress sensors that are not affected by harsh and changing environment and do not fail under catastrophic conditions is a fundamental challenge. To address this problem, we developed a stress sensor based on creased single-walled carbon nanotubes (SWCNTs) encapsulated in a non-fluorinated superhydrophobic coating. The creased SWCNT film was fabricated and integrated in polydimethylsiloxane (PDMS) to provide a highly linear response under elastic deformation. The non-fluorinated water-repellent coating was fabricated by spray-coating the film with nanosilica particles, providing water resistance during elastic deformation. The compact design and superior water resistance of the sensor, along with its appealing linearity and large stretchability, demonstrates the scalability of this approach for fabricating efficient strain sensors for applications in infrastructure and robotic safety management as well as advanced wearable sensors.