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Carbon Diffusion from Methane into Walls of Carbon Nanotube through Structurally and Compositionally Modified Iron Catalyst

Published online by Cambridge University Press:  27 May 2011

Michael J. Behr ,
K. Andre Mkhoyan  and
Eray S. Aydil
Michael J. Behr
Affiliation:
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
K. Andre Mkhoyan*
Affiliation:
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
Eray S. Aydil*
Affiliation:
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
*
Corresponding author. E-mail: [email protected]
Corresponding author. E-mail: [email protected]
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Abstract

To understand diffusion processes occurring inside Fe catalysts during multiwall carbon nanotube (MWCNT) growth, catalysts were studied using atomic-resolution scanning transmission electron microscopy combined with electron energy-loss spectroscopy. Nanotube walls emanate from structurally modified and chemically complex catalysts that consist of cementite and a 5 nm amorphous FeOx cap separated by a 2–3 nm thick carbon-rich region that also contains Fe and O (a-C:FexOy). Nonuniform distribution of carbon atoms throughout the catalyst base reveals that carbon molecules from the gas phase decompose near the catalyst multisection junction, where the MWCNT walls terminate. Formation of the a-C:FexOy region provides the essential carbon source for MWCNT growth. Two different carbon diffusion mechanisms are responsible for the growth of the inner and outer walls of each MWCNT.

Keywords

carbon nanotubecatalystironcementitediffusionSTEMEELS
Type
Materials Applications
Information
Microscopy and Microanalysis , Volume 17 , Issue 4 , August 2011 , pp. 582 - 586
Copyright
Copyright © Microscopy Society of America 2011

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References

REFERENCES

Barone, P.W., Baik, S., Heller, D.A. & Strano, M.S. (2005). Near-infrared optical sensors based on single-walled carbon nanotubes. Nat Mater 4, 86–92.CrossRefGoogle ScholarPubMed
Batson, P.E. (1993a). Simultaneous STEM imaging and electron energy-loss spectroscopy with atomic-column sensitivity. Nature 366, 727–728.CrossRefGoogle Scholar
Batson, P.E. (1993b). Carbon 1s near-edge-absorption fine structure in graphite. Phys Rev B 48, 2608–2610.CrossRefGoogle ScholarPubMed
Baughman, R.H., Zakhidov, A.A. & de Heer, W.A. (2002). Carbon nanotubes—The route toward applications. Science 297, 787–792.CrossRefGoogle ScholarPubMed
Begtrup, G.E., Gannett, W., Meyer, J.C., Yuzvinsky, T.D., Ertekin, E., Grossman, J.C. & Zettl, A. (2009). Facets of nanotube synthesis: High-resolution transmission electron microscopy study and density functional theory calculations. Phys Rev B 79, 205409.CrossRefGoogle Scholar
Behr, M.J., Gaulding, E.A., Mkhoyan, K.A. & Aydil, E.S. (2010a). Effects of hydrogen on catalyst nanoparticles in carbon nanotube growth. J Appl Phys 108, 053303.CrossRefGoogle Scholar
Behr, M.J., Mkhoyan, K.A. & Aydil, E.S. (2010b). Orientation and morphological evolution of catalyst nanoparticles during carbon nanotube growth. ACS Nano 4, 5087–5094.CrossRefGoogle ScholarPubMed
Behr, M.J., Mkhoyan, K.A. & Aydil, E.S. (2010c). Catalyst rotation, twisting, and bending during multiwall carbon nanotube growth. Carbon 48, 3840–3845.CrossRefGoogle Scholar
Blank, V.D., Kulnitskiy, B.A., Batov, D.V., Bangert, U., Gutiérrez-Sosa, A. & Harvey, A.J. (2002). Electron microscopy and electron energy loss spectroscopy studies of carbon fiber formation at Fe catalysts. J Appl Phys 91, 1657–1660.Google Scholar
Bosman, M., Keast, V.J., García-Muñoz, J.L., D'Alfonso, A.J., Findlay, S.D. & Allen, L.J. (2007). Two-dimensional mapping of chemical information at atomic resolution. Phys Rev Lett 99, 086102.Google Scholar
Carlson, L.J., Maccagnano, S.E., Zheng, M., Silcox, J. & Krauss, T.D. (2007). Fluorescence efficiency of individual carbon nanotubes. Nano Lett 7, 3698–3703.CrossRefGoogle ScholarPubMed
Dresselhaus, M.S., Dresselhaus, G., Charlier, J.C. & Hernandez, E. (2004). Electronic, thermal and mechanical properties of carbon nanotubes. Phil Trans R Soc Lond 362, 2065–2098.CrossRefGoogle ScholarPubMed
Egerton, R. (1996). Electron Energy Loss Spectroscopy in the Electron Microscope. New York: Plenum.CrossRefGoogle Scholar
Enache, D.I., Edwards, J.K., Landon, P., Solsona-Espriu, B., Carley, A.F., Herzing, A.A., Watanabe, M., Kiely, C.J., Knight, D.W. & Hutchings, G.J. (2006). Solvent-free oxidation of primary alcohols to aldehydes using Au-Pd/TiO2 catalysts. Science 311, 362–365CrossRefGoogle ScholarPubMed
Golberg, D., Mitome, M., Muller, C., Tang, C.C., Leonhardt, A. & Bando, Y. (2006). Atomic structures of iron-based single-crystalline nanowires crystallized inside multi-walled carbon nanotubes as revealed by analytical electron microscopy. Acta Mater 54, 2567–2576.CrossRefGoogle Scholar
Grabke, H.J. (2003). Metal dusting. Mater Corros 54, 736–740.CrossRefGoogle Scholar
Helveg, S., López-Cartes, C., Sehested, J., Hansen, P.L., Clausen, B.S., Rostrup-Nielsen, J.R., Abild-Pedersen, F. & Nørskov, J.K. (2004). Atomic-scale imaging of carbon nanofibre growth. Nature 427, 426–429.CrossRefGoogle ScholarPubMed
Hofmann, S., Csanyi, G., Ferrari, A.C., Payne, M.C. & Robertson, J. (2005). Surface diffusion: The low activation energy path for nanotube growth. Phys Rev Lett 95, 036101.CrossRefGoogle ScholarPubMed
Huang, J.Y. (1999). HRTEM and EELS studies of defects structure and amorphous-like graphite induced by ball milling. Acta Mater 47, 1801–1808.CrossRefGoogle Scholar
Jin, Y.M., Xu, H.F. & Datye, A.K. (2006). Electron energy loss spectroscopy (EELS) of iron Fischer-Tropsch catalysts. Microsc Microanal 12, 124–134.CrossRefGoogle ScholarPubMed
Kim, H. & Sigmund, W. (2005). Iron particles in carbon nanotubes. Carbon 43, 1743–1748.CrossRefGoogle Scholar
Melechko, A.V., Merkulov, V.I., McKnight, T.E., Guillorn, M.A., Klein, K.L., Lowndes, D.H. & Simpson, M.L. (2005). Vertically aligned carbon nanofibers and related structures: Controlled synthesis and directed assembly. J Appl Phys 97, 041301.CrossRefGoogle Scholar
Meyyappan, M. (2009). A review of plasma enhanced chemical vapour deposition of carbon nanotubes. J Phys D Appl Phys 42, 213001.CrossRefGoogle Scholar
Mkhoyan, K.A., Kirkland, E.J., Silcox, J. & Alldredge, E.S. (2004). Atomic-level characterization of GaN/AlN quantum wells. J Appl Phys 96, 738–741.CrossRefGoogle Scholar
Raty, J.Y., Gygi, F. & Galli, G. (2005). Growth of carbon nanotubes on metal nanoparticles: A microscopic mechanism from ab initio molecular dynamics simulations. Phys Rev Lett 95, 096103.CrossRefGoogle ScholarPubMed
Ren, Z.F., Huang, Z.P., Xu, J.W., Wang, J.H., Bush, P., Siegal, M.P. & Provencio, P.N. (1998). Synthesis of large arrays of well-aligned carbon nanotubes on glass. Science 282, 1105–1107.CrossRefGoogle Scholar
Rodríguez-Manzo, J.A., Terrones, M., Terrones, H., Kroto, H.W., Sun, L. & Banhart, F. (2007). In situ nucleation of carbon nanotubes by the injection of carbon atoms into metal particles. Nat Nanotechnol 2, 307–311.CrossRefGoogle ScholarPubMed
Schaper, A.K., Hou, H.Q., Greiner, A. & Phillipp, F. (2004). The role of iron carbide in multiwalled carbon nanotube growth. J Catal 222, 250–254.CrossRefGoogle Scholar
Sharma, R., Moore, E., Rez, P. & Treacy, M.M.J. (2009). Site-specific fabrication of Fe particles for carbon nanotube growth. Nano Lett 9, 689–694.Google Scholar
Tans, S.J., Verschueren, A.R.M. & Dekker, C. (1998). Room-temperature transistor based on a single carbon nanotube. Nature 393, 49–52.CrossRefGoogle Scholar
Wirth, C.T., Zhang, C., Zhong, G.F., Hofmann, S. & Robertson, J. (2009). Diffusion- and reaction-limited growth of carbon nanotube forests. ACS Nano 3, 3560–3566.CrossRefGoogle ScholarPubMed
Xu, C.H., Fu, C.L. & Pedraza, D.F. (1993). Simulations of point-defect properties in graphite by a tight-binding-force model. Phys Rev B 48, 13273–13279.Google Scholar
Yao, Y., Falk, L.K.L., Morjan, R.E., Nerushev, O.A. & Campbell, E.E.B. (2004a). Synthesis of carbon nanotube films by thermal CVD in the presence of supported catalyst particles. Part I: The silicon substrate/nanotube film interface. J Mater Sci Mater Electron 15, 533–543.CrossRefGoogle Scholar
Yao, Y., Falk, L.K.L., Morjan, R.E., Nerushev, O.A. & Campbell, E.E.B. (2004b). Synthesis of carbon nanotube films by thermal CVD in the presence of supported catalyst particles. Part II: The silicon substrate/nanotube film interface. J Mater Sci Mater Electron 15, 583–594.CrossRefGoogle Scholar
Yoshida, H., Takeda, S., Uchiyama, T., Kohno, H. & Homma, Y. (2008). Atomic-scale in-situ observation of carbon nanotube growth from solid state iron carbide nanoparticles. Nano Lett 8, 2082–2086.Google Scholar