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1956265 
Journal Article 
The role of phosphorus in the growth of vapour-grown carbon fibres obtained by catalytic decomposition of hydrocarbons 
Benissad-Aissani, F; Ait-Amar, H; Schouler, MC; Gadelle, P 
2004 
Yes 
Carbon
ISSN: 0008-6223
EISSN: 1873-3891 
Elsevier 
42 
11 
2163-2168 
WOS:000223244000005 
Production of VGCF fibres from the decomposition of a methane-hydrogen mixture over metal particles is influenced by the support on which the particles have been laid. It was found that different as-received commercial graphite supports, according to their impurity content, could promote or inhibit the VGCF growth.



Good yields of vapour-grown carbon fibres with a length up to 6 cm have been fabricated by catalytic decomposition of methane over particles obtained from Fe-3(CO)(12). Addition to the substrate of small amounts of phosphorus from a solution of H3PO4 in ethanol, followed by impregnation with Fe-3(CO)(12), was found to be effective in promoting the growth of VGCFs and increasing the yield. But increasing the amount of phosphorus over P/Fesimilar to0.25 had an inhibiting effect on the growth of VGCFs. So the yield of VGCFs was optimized for a given phosphorus concentration.



These phenomena are interpreted by the formation of Fe-P compounds which, depending on their formulae, lower or increase the melting point of the catalyst particles. According to the VLS theory, catalytic growth up to a macroscopic scale results from the liquid state of the catalyst. (C) 2004 Elsevier Ltd. All rights reserved. 
carbon fibres; carbon nanotubes; chemical vapour deposition