abstract
Multi-walled CNTs (MWCNTs) with structural characteristics optimised for bio-applications have been produced using a catalyst-supported chemical vapour deposition (CVD) method. The upscale potential of the process was demonstrated by combining classical semi-continuous and stacked-growth modes. The vertically aligned MWCNT films thus obtained were multi-layered with five continuous strata of well-structured nanotubes. Following gentle disentanglement, the stacks were converted to individual MWCNTs with short dimensions (a final length and diameter of similar to 1.2 mu m and similar to 12 nm) and almost catalyst-free (<0.04%). Overall, our process produces dispersed, bio-tailored MWCNTs with an output growth-yield 20 times higher than a standard CVD setup and exempt of complex or destructive post-growth steps of purification and separation. These constitute key steps towards the mass production of MWCNTs with low toxicological risks, an essential prerequisite for biomedical applications. (C) 2012 Elsevier Ltd. All rights reserved.
keywords
CHEMICAL-VAPOR-DEPOSITION; FILAMENTOUS CARBON; DIFFUSION; IRON; NANOTOXICOLOGY; NANOPARTICLES; TOXICITY; KINETICS; DEACTIVATION; MULTILAYERS
subject category
Chemistry; Materials Science
authors
Mata, D; Silva, RM; Fernandes, AJS; Oliveira, FJ; Costa, PMFJ; Silva, RF
our authors
Diogo Miguel Rodrigues Marinho da Mata
Post-doc Fellowship
Filipe José Alves de Oliveira
Principal Researcher
Ricardo Manuel Fonseca Lopes da Silva
Junior Researcher
Rui Ramos Ferreira e Silva
Associate Professoracknowledgements
D. Mata is very grateful to FCT for the grant SFRH/BD/36273/2007.