文档介绍：ARTICLE IN PRESS
Physica E ] (]]]]) ]]]–]]]
ate/physe
Carbon nanotubes growth from C2H2 and C2H4/NH3 by catalytic
LCVD on supported iron–carbon posites
I. Morjana, I. Soarea,Ã, R. Alexandrescua, R.-E. Morjanb, L. Gavrila-Florescua, G. Prodanc,
I. Sandua, E. Popovicia, F. Dumitrachea, I. Voicua, M. Scarisoreanua
aNational Institute for Lasers, Plasma and Radiation Physics Atomistilor 409, . Box: MG-36, 077125 Bucharest Romania
bDepartament of Applied Physics, Chalmers University of Technology and University, SE- 412 96, , Sweden
cOvidius University Constanta, 124 B-dul Mamaia, Constanta, Romania
Abstract
We report about the synthesis of carbon nanotubes by catalytic LCVD (C-LCVD), using a CW CO2 laser and alternatively, C2H2/
C2H4/NH3 and C2H2/C2H4-containing gas mixtures. Different core–shell Fe–C posites (as synthesized and toluene extracted)
were used employed as catalysts. The nanotubes grown from Fe–C residue demonstrate the lowest mean diameters. Prevalent curled and
coiled morphologies are obtained for Ts grown in the presence of ammonia.
r 2006 Elsevier . All rights reserved.
PACS: ; ; ;
Keywords: Cargon nanotubes; Catalytic LCVD; Fe–C posites; Ammonia precursor; Coiled shape
1. Introduction phase. The LCVD technique in general has several
prominent advantages including high deposition rates, that
Car