Functionalization of vertically aligned carbon nanotubes

Abstract

SummaryThis review focuses and summarizes recent studies on the functionalization of carbon nanotubes oriented perpendicularly to their substrate, so-called vertically aligned carbon nanotubes (VA-CNTs). The intrinsic properties of individual nanotubes make the VA-CNTs ideal candidates for integration in a wide range of devices, and many potential applications have been envisaged. These applications can benefit from the unidirectional alignment of the nanotubes, the large surface area, the high carbon purity, the outstanding electrical conductivity, and the uniformly long length. However, practical uses of VA-CNTs are limited by their surface characteristics, which must be often modified in order to meet the specificity of each particular application. The proposed approaches are based on the chemical modifications of the surface by functionalization (grafting of functional chemical groups, decoration with metal particles or wrapping of polymers) to bring new properties or to improve the interactions between the VA-CNTs and their environment while maintaining the alignment of CNTs.

High-performance field emission device utilizing vertically aligned carbon nanotubes-based pillar architectures

“…In the orientation of CNTs, the outer wall of each nanotube interacts with the outer walls of neighboring nanotubes due to nm, vander Waals interaction, which results to form large bundles with sufficient rigidity to keep the growth direction. 12 It means that the density of CNTs approaches the aligned growth. This can be clearly seen in Fig.…”

Fabrication of three dimensional layered vertically aligned carbon nanotube structures and their potential applications

“…specific biomolecules for biosensing applications. 34 Another approach is to attach functional groups such as carboxylic acid groups to the nanotube ends as anchoring sites for other molecules. 35 The growth of a layer--by--layer forest structure would potentially allow for each layer to be functionalised differently, increasing the versatility of functionalised nanotubes for novel applications.…”

Integration and Bio-Functionalization of Vertically Aligned Carbon Nanotube Forests on High Frequency AlN Gravimetric Sensors

“…CNT forests of controlled quality and surface density can be directly integrated on resonators, thus obtaining a platform with a large area for biofunctionalization. The functionalization chemistry of CNTs has been widely studied [4], but carrying it out directly on the resonators without compromising their performance is not straightforward. In this work we directly grow CNTs over the top electrode of AlN-based resonators.…”