Carbon nanotube synthesis on catalytic metal alloys in methane/air counterflow diffusion flames
نویسندگان
چکیده
Various morphologies of multi-walled carbon nanotubes (MWNTs) are grown catalytically on metalalloy probes in counterflow diffusion flames using methane as fuel. Carbon nanotube (CNT) properties and morphologies are investigated as functions of local gas-phase temperatures, C-related species concentrations (e.g. C2H2, CO), sampling positions, C2H2 adding to the fuel, and metal-alloy compositions (i.e., Fe, Fe/Cr, Ni/Cu, Ni/Ti, Ni/Cr, Ni/Cr/Fe). MWNTs grow optimally in non-sooty regions of the flames. C2H2 addition is found to promote direct synthesis of vertically well-aligned MWNTs with uniform diameters from Ni/Cr/Fe and Ni/Ti alloys. 2006 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
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Synthesis of carbon nanotubes on Ni-alloy and Si-substrates using counterflow methane–air diffusion flames
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