Authors: R Bonadiman M D Lima M J de Andrade C P Bergmann
Publish Date: 2006/10/26
Volume: 41, Issue: 22, Pages: 7288-7295
Abstract
In this work the Catalytic Chemical Vapor Deposition CCVD technique was used to synthesize carbon nanotubes CNT Natural gas NG was employed as a carbon source for the growing of CNT while magnesium oxide was used as a catalyst support for the nanotubes synthesis Two systems were utilized The Fe–Mo/MgO system was obtained by the impregnation technique through the dispersion of iron oxide which is the catalyst over magnesia with molybdenum additions This system was tested intending to optimize the parameters for the production of singlewalled carbon nanotubes SWCNT Moreover Mg1−x Fe x MoO4 which was prepared by the combustion synthesis method was tested to produce multiwalled carbon nanotubes MWCNT The FeMo/MgO tests were carried out under H2/GN and Ar/GN atmospheres at 950 °C whereas the Mg1−x Fe x MoO4 was submitted to 1000 °C under H2/GN atmosphere The Fe–Mo/MgO catalyst produced better results regarding number of CNT and their diameters under Ar/NG atmospheres than under H2/NG atmospheres The system Mg1−x Fe x MoO4 produced MWCNT according to the expectationsAuthors are grateful to the members of Laboratory of Ceramic Materials LACER for their contribution to the development of this study to the CME/UFRGS Electron Microscopy Center of the Federal University of Rio Grande do Sul staff who made the SEM and TEM analysis possible and to the High Pressures Laboratory of the UFRGS Physics Institute personnel
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