Sensing abilities of embedded vertically aligned carbon nanotube forests in structural composites: From nanoscale properties to mesoscale functionalities

Abstract

In this paper, Vertically Aligned Carbon Nanotube (VACNT) forests are embedded into two different glass fibre/epoxy composite systems to study their sensing abilities to strain and temperature. Through a bottom-up approach, performing studies of the VACNT forest and its individual carbon nanotubes on the nano-, micro-, and mesoscale, the observed thermoresistive effect is determined to be due to fluctuation-assisted tunnelling, and the linear piezoresistive effect due to the intrinsic piezoresistivity of individual carbon nanotubes. The VACNT forests offer great freedom of placement into the structure and reproducibility of sensing sensitivity in both composite systems, independent of conductivity and volume fraction, producing a robust sensor to strain and temperature.