New routes for carbon nanostructures growth with applications in structural composite materials and environmental remediation

This PhD research work investigates the direct growth of carbon nanostructures, particularly carbon nanotubes (CNTs), on the surface of reinforcing fibres as a strategy for the development of both high-performance and multifunctional structural composite materials. Innovative catalyst systems and a plasma-enhanced chemical vapour deposition (PE-CVD) technique are proposed as alternatives to more common catalysts and traditional thermal CVD to lower CVD process temperatures — usually above 600 °C — which can significantly degrade the mechanical properties of the fibre substrate. The work includes a systematic optimization of the CVD process parameters as well as the investigation of the effects of high-temperature exposure on the mechanical properties of the fibre materials selected as substrates for CNT growth, i.e., quartz and basalt fibres. Finally, the properties of CNT-modified fibres are investigated in terms of wettability towards an epoxy matrix and additional electrochemical functions provided by CNT introduction, showcasing potential applications in the field of environmental remediation and in electrochemical devices, such as those for energy harvesting and storage.