resumo
A study of wet-chemical etching treatments for nickel foils and the growth parameters for carbon nanostructures on them using hot-filament chemical vapour deposition (CVD) is described. Catalytically-active protrusions were produced on the Ni foils with sizes and densities in the range similar to 24-42 nm and similar to 202-314 P mu m(-2), respectively. These protrusions are found to have a key role in the growth process as they determine the yield and morphology of the carbon deposits. It is shown that well-shaped, nano-sized protrusions are required to achieve high yield growth of hollow-herringbone carbon nanofibers (CNFs) with an in-plane crystallite size of similar to 23 nm. Good correlation was seen between the statistical distributions of the protrusion size (sp) and the CNF diameters (df) depicting sp/df ratios close to unity. This work sheds light on the mechanisms behind CVD growth on metal foils. (C) 2010 Elsevier Ltd. All rights reserved.
palavras-chave
CHEMICAL-VAPOR-DEPOSITION; HETEROGENEOUS CATALYSIS; FILAMENTOUS CARBON; RAMAN-SPECTROSCOPY; NANOTUBE GROWTH; THERMAL CVD; SURFACE; COMPOSITES; IRON; DECOMPOSITION
categoria
Chemistry; Materials Science
autores
Mata, D; Ferro, M; Fernandes, AJS; Amaral, M; Oliveira, FJ; Costa, PMFJ; Silva, RF
nossos autores
Diogo Miguel Rodrigues Marinho da Mata
Bolseiro de pós-Doutoramento
Filipe José Alves de Oliveira
Investigador Principal
Rui Ramos Ferreira e Silva
Professor associadoagradecimentos
D. Mata and M. Amaral are very grateful to FCT for the Grants SFRH/BD/36273/2007 and SFRH/BDP/26787/2006, respectively.