Effect of rare-earth component of the RE/Ni catalyst on the formation and nanostructure of single-walled carbon nanotubes
2006 (English)In: Journal of Physical Chemistry B, ISSN 1520-6106, Vol. 110, no 31, 15284-15290 p.Article in journal (Refereed) Published
A systematic experimental study has been carried out on the efficiency of bimetallic catalysts based on Ni and the rare-earth elements Y, La, Ce, Nd, Gd, Tb, Dy, Ho, Er, and Lu ( group A) and Eu, Sm, Yb, and Tm ( group B) in the synthesis of single-walled carbon nanotubes (SWNTs). The two groups give quite different results when analyzed by a combination of SEM/TEM and Raman and UV-NIR spectroscopies. The elements in group A have an obvious catalytic effect and increase the yield of SWNTs dramatically, whereas those in group B are not efficient catalysts. The diameter distribution of the synthesized SWNTs was also affected by the rare-earth element used. For group A metals, there is a tendency that the fraction of small-diameter tubes decreases with decreasing ionic radius of the rare-earth element used. EDX and X-ray analyses indicate that group A metals deposit on the cathode deposits and form rare-earth carbides, whereas no group B metals are found in cathode deposits, except for a small amount of Tm present in the form of thulium carbide. Further analysis indicates that there is a very strong correlation between the ability to form rare-earth carbides and the catalytic efficiency for the formation of SWNTs.
Place, publisher, year, edition, pages
2006. Vol. 110, no 31, 15284-15290 p.
Carbon nanotubes, Single walled carbon nanotubes, SWNT, synthesis, catalyst, rare earths, Raman spectroscopy, UV, IR, NIR, SEM, TEM, yield, EDX, carbides
Condensed Matter Physics
IdentifiersURN: urn:nbn:se:umu:diva-12467DOI: 10.1021/jp060942bOAI: oai:DiVA.org:umu-12467DiVA: diva2:152138