II International Symposium on Carbon for Catalysis ABSTRACTS

OP-<strong>II</strong>-1
SYNTHESIS OF MULTI-WALLED CARBON NANOTUBES WITH CONTROLLED
MACROSCOPIC SHAPES
Amadou J., Nguyen P., Tessonnier J.-P., Begin D., Janowska I., Dintzer T.,
Vanhaecke E., Ledoux M.J., Cuong Pham-Huu
Laboratoire des Matériaux, Surfaces et Procédés pour la Catalyse,ECPM-Université Louis
Pasteur 25, rue Becquerel, 67087 Strasbourg Cedex 02, France, Member of the European
Laboratory for Catalysis and Surface Science (ELCASS)
e-mail: begind@ecpm.u-strasbg.fr
Carbon nanotubes have recently received increasing interest due to their exceptional
physical and chemical properties [1,2]. During their growth, MWNTs are highly entangled
and interconnected, forming a dense and elastic network generally on a microscopic scale
which render their direct use complicated because of their fluffy character. Thus, a postsynthesis
treatment is needed to obtain a macroscopic shape. Such a post-treatment generally
requires to mix the as-synthesized carbon nanotubes with a polymer or a chemical agent
before processing the macroscopic shape. Processing carbon nanotubes with macroscopic
shapes to obtain materials with practical use is nowadays a major challenge in the field of
advanced materials. In the present work, we report the synthesis of pure MWNTs selfsupported
in a macroscopic shape, i.e., cylinder, disk, cube, etc…, at several centimeter scale
using a CVD synthesis under macroscopic constraint without any need of foreign agent
addition during the process [3]. The synthesis method allows the complete control of the
macroscopic shapes of the carbon nanotubes by controlling the constraint shape of the
macroscopic reactor in which the carbon nanotubes were grown. The synthesis method was
extremely simple, based on a conventional CVD method which allows easy scaling-up with
minimum cost investment. The as-synthesized self-supported MWNTs were subsequently
used as a reversible adsorber for the removal of organic pollutants from water [4] or as
catatlyst support.
The raw material, i.e. MWNTs, was obtained by a CVD method using a mixture of
ethane and hydrogen and an iron-based catalyst (20 to 50 wt.%). The self-organized MWNTs
with a macroscopic shape were made by placing the powder catalyst inside a quartz cylinder
(inner diameter, 30 mm, length, 50 mm) with both ends closed by a gas-permeable disk of
carbon felt made of an entangled network of micrometers carbon filaments purchased from
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