TY - GEN
T1 - Support controlled catalytic chemical vapor deposition of carbon nanotubes
AU - Wang, Yunyu
AU - Li, Bin
AU - Luo, Zhiquan
AU - Shi, Li
AU - Yao, Zhen
AU - Bryan, Eugene N.
AU - Nemanich, Robert
AU - Ho, Paul S.
PY - 2007
Y1 - 2007
N2 - Carbon nanotubes (CNT5) have been grown by catalytical chemical vapor deposition (CCVD) with a thin iron layer as the catalyst. High surface tension metal, tantalum (Ta). and low surface tension, 5i02, have been deposited as the supporting layers before depositing the catalysts. SEM, TEM, STEM and EELS have been used to examine the morphology, structure, and chemical profile of iron nanoparticles and CNTs. The results have shown that the catalyst nanoparticle morphologies were distinctly different on two supports. In particular, Fe nanoparticles on 5i02 were found to follow a Volimer-Weber (VW) growth mode and a Stranski Krastanov (SK) growth mode on Ta. It was also found that CNT growth varied significantly on two supports in terms of morphology, growth rate and growth mode. Dense CNTs were grown on Ta with fast growth rates (> him/mm) and vertical alignment for the iron thicknesses of 1.5-9 nm. In contrast, CNTs grown on 5i02 exhibited a slow growth rate (< 100 nm/mm) with all deposited iron thicknesses, indicating a severe catalyst poisoning. The results suggested that the catalyst morphology in combination with the presence of an iron wetting layer contributed to the enhanced CCVD growth of CNTs on Ta.
AB - Carbon nanotubes (CNT5) have been grown by catalytical chemical vapor deposition (CCVD) with a thin iron layer as the catalyst. High surface tension metal, tantalum (Ta). and low surface tension, 5i02, have been deposited as the supporting layers before depositing the catalysts. SEM, TEM, STEM and EELS have been used to examine the morphology, structure, and chemical profile of iron nanoparticles and CNTs. The results have shown that the catalyst nanoparticle morphologies were distinctly different on two supports. In particular, Fe nanoparticles on 5i02 were found to follow a Volimer-Weber (VW) growth mode and a Stranski Krastanov (SK) growth mode on Ta. It was also found that CNT growth varied significantly on two supports in terms of morphology, growth rate and growth mode. Dense CNTs were grown on Ta with fast growth rates (> him/mm) and vertical alignment for the iron thicknesses of 1.5-9 nm. In contrast, CNTs grown on 5i02 exhibited a slow growth rate (< 100 nm/mm) with all deposited iron thicknesses, indicating a severe catalyst poisoning. The results suggested that the catalyst morphology in combination with the presence of an iron wetting layer contributed to the enhanced CCVD growth of CNTs on Ta.
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U2 - 10.1557/proc-1017-dd01-04-ee01-04
DO - 10.1557/proc-1017-dd01-04-ee01-04
M3 - Conference contribution
AN - SCOPUS:70349925574
SN - 9781605604237
T3 - Materials Research Society Symposium Proceedings
SP - 1
EP - 7
BT - Materials Research Society Symposium Proceedings - Low-Dimensional Materials- Synthesis, Assembly, Property Scaling, and Modeling
PB - Materials Research Society
T2 - Low-Dimensional Materials- Synthesis, Assembly, Property Scaling, and Modeling - 2007 MRS Spring Meeting
Y2 - 9 April 2007 through 13 April 2007
ER -