کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1419627 | 986052 | 2006 | 8 صفحه PDF | دانلود رایگان |

Catalytically grown carbon nanofibers, a novel mesoporous carbon material for catalysis, were synthesized by the decomposition of carbon-containing gases (CH4, C2H4 or CO) over supported nickel-iron alloy and unsupported iron. It was shown that the structures of as-synthesized and modified CNFs, including the arrangement of the graphenes in CNF, and the crystallinity and texture of CNF depended on the catalyst composition and the type of carbon-containing gas. Three types of CNFs with different microstructures were obtained: platelet CNF (Fe–CO), fishbone CNF (supported Ni–Fe alloy-CH4, C2H4 or CO) and tubular CNF (supported Ni–CO). All the CNFs were mesoporous carbon materials possessing relatively high surface areas (86.6–204.7 m2/g) and were highly graphitic. Purification with acid-base treatments or high temperature treatment removed the catalyst residue without changing the basic structures of the CNFs. However, annealing significantly decreased their surface areas through the formation of loop-shaped ends on the CNF surfaces. Oxidative modification in the gas and liquid phases changed the structures only slightly, except for oxidation in air at 700 °C. The structures and textures were studied using SEM, TEM, XRD, BET and TGA.
Journal: Carbon - Volume 44, Issue 15, December 2006, Pages 3255–3262