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The Origin of Long-Period Lattice Spacings Observed in Iron-Carbide Nanowires Encapsulated by Multiwall Carbon Nanotubes

Published online by Cambridge University Press:  02 July 2013

Filippo S. Boi ,
Gavin Mountjoy ,
Zofia Luklinska ,
Liam Spillane ,
Lisa S. Karlsson ,
Rory M. Wilson ,
Anna Corrias  and
Mark Baxendale
Filippo S. Boi
Affiliation:
School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS, UK
Gavin Mountjoy
Affiliation:
School of Physical Sciences, University of Kent, Canterbury CT2 7NH, UK
Zofia Luklinska
Affiliation:
School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, UK
Liam Spillane
Affiliation:
Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ, UK
Lisa S. Karlsson
Affiliation:
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
Rory M. Wilson
Affiliation:
School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, UK
Anna Corrias
Affiliation:
Dipartimento di Scienze Chimiche, Università di Cagliari, I-09042 Monserrato Cagliari, Italy
Mark Baxendale*
Affiliation:
School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS, UK
*
*Corresponding author. E-mail: [email protected]
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Abstract

Structures comprising single-crystal, iron-carbon-based nanowires encapsulated by multiwall carbon nanotubes self-organize on inert substrates exposed to the products of ferrocene pyrolysis at high temperature. The most commonly observed encapsulated phases are Fe3C, α-Fe, and γ-Fe. The observation of anomalously long-period lattice spacings in these nanowires has caused confusion since reflections from lattice spacings of ≥0.4 nm are kinematically forbidden for Fe3C, most of the rarely observed, less stable carbides, α-Fe, and γ-Fe. Through high-resolution electron microscopy, selective area electron diffraction, and electron energy loss spectroscopy we demonstrate that the observed long-period lattice spacings of 0.49, 0.66, and 0.44 nm correspond to reflections from the (100), (010), and (001) planes of orthorhombic Fe3C (space group Pnma). Observation of these forbidden reflections results from dynamic scattering of the incident beam as first observed in bulk Fe3C crystals. With small amounts of beam tilt these reflections can have significant intensities for crystals containing glide planes such as Fe3C with space groups Pnma or Pbmn.

Keywords

iron carbidenanowireforbidden reflectionsHRTEM
Type
Materials Applications
Information
Microscopy and Microanalysis , Volume 19 , Issue 5 , October 2013 , pp. 1298 - 1302
Copyright
Copyright © Microscopy Society of America 2013 

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Footnotes

†

Current address: Sandvik AB, Kungsbron 1, Stockholm, Sweden

References

Bi, X.-X., Ganguly, B., Huffman, G.P., Huggins, F.E., Endo, M. & Eklund, P. (1993). Nanocrystalline a-Fe, Fe3C, and Fe7C3 produced by CO2 laser pyrolysis. J Mater Res 8(7), 1666–1674.Google Scholar
Callister, W.D. (2007). Fundamentals of Materials Science and Engineering. Hoboken, NJ: John Wiley and Sons.Google Scholar
Cowley, J.M. & Moodie, A.F. (1959). The scattering of electrons by atoms and crystals. III. Single-crystal diffraction patterns. Acta Cryst 12, 360–367.CrossRefGoogle Scholar
Gjonnes, J. & Moodie, A.F. (1965). Extinction conditions in the dynamic theory of electron diffraction. Acta Cryst 19, 65–67.CrossRefGoogle Scholar
Goldberg, D., Mitome, M., Müller, C., Tang, 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
Grobert, N., Hsu, W.K., Zhu, Y.Q., Hare, J.P., Kroto, H.W., Walton, D.R.M., Terrones, M., Terrones, H., Redlich, Ph., Ruhle, M., Escudero, R. & Morales, F. (1999). Enhanced magnetic coercivities in Fe nanowires. Appl Phys Lett 75, 3363–3365.Google Scholar
Hammond, C. (2009). The Basics of Crystallography and Diffraction. Oxford, UK: Oxford Science Publications.Google Scholar
Kurata, H. & Tanaka, N. (1991). Iron L2,3 white line ratio in nm-sized γ-iron crystallites embedded in MgO. Microsc Microanal Microstruct 2, 183–190.CrossRefGoogle Scholar
Leapman, R.D., Grunnes, L.A. & Fejes, P.L. (1982). Study of the L23 edges in the 3d transition metals and their oxides by electron-energy-loss spectroscopy with comparisons to theory. Phys Rev B 26, 614–635.CrossRefGoogle Scholar
Lee, Y.H., Han, T.C., Huang, J.C.A. & Lin, C.R. (2003). Analysis of microstructure of magnetic Fe3C nanograins embedded in amorphous carbon films. J Appl Phys 94, 1975–1978.CrossRefGoogle Scholar
Lutz, M.U., Weissker, U., Wolny, F., Müller, C., Löffler, M., Mühl, T., Leonhardt, A., Büchner, B. & Klingeler, R. (2010). Magnetic properties of α-Fe and Fe3C nanowires. J Phys: Conf Ser 200, 072062. Google Scholar
Marco, J.F., Gancedo, J.R., Hernando, A., Crespo, P., Prados, C., González, J.M., Grobert, N., Terrones, M., Walton, D.R.M. & Kroto, H.W. (2002). Mössbauer study of iron-containing carbon nanotubes. Hyperfine Interact 139–140, 535–542.CrossRefGoogle Scholar
Müller, C., Goldberg, D., Leonhardt, A., Hamel, S., Büchner, B. (2006). Growth studies, TEM and XRD investigations of iron-filled carbon nanotubes. Phys Stat Sol (a) 203, 1064–1068.CrossRefGoogle Scholar
Nagakura, S., Nakamura, Y. & Suzuki, T. (1982). Forbidden reflection intensity in electron diffraction and its influence on the crystal structure image. Jpn J Appl Phys 21, L449–L451.Google Scholar
Pearson, D.H., Ahn, C.C. & Fultz, B. (1993). White lines and d-electron occupancies for the 3d and 4d transition metals. Phys Rev B 47, 8471–8478.CrossRefGoogle ScholarPubMed
Prados, C., Crespo, P., González, J.M., Hernando, A., Marco, J.F., Gancedo, R., Grobert, N., Terrones, M., Walton, D.R.M. & Kroto, H.W. (2002). Hysteresis shift in Fe-filled carbon nanotubes due to γ-Fe. Phys Rev B 65, 113405–113409.CrossRefGoogle Scholar
Rao, C.N.R., Sen, R., Satishkumar, B.C. & Govindaraj, A. (1998). Large aligned-nanotube bundles from ferrocene pyrolysis. Chem Comm 15, 1525–1526.CrossRefGoogle Scholar
Reibold, M., Paufler, P., Levin, A.A., Kocmann, W., Pätzke, N. & Meyer, D.C. (2006). Materials: Carbon nanotubes in an ancient Damascus sabre. Nature 444, 286.CrossRefGoogle Scholar
Riedl, T., Gemming, T. & Wetzig, K. (2006). Extraction of EELS white-line intensities of manganese compounds: Methods, accuracy, and valence sensitivity. Ultramicroscopy 106, 284–291.CrossRefGoogle ScholarPubMed
Sen, R., Govindaraj, A. & Rao, C.N.R. (1997). Carbon nanotubes by the metallocene route. Chem Phys Lett 267, 276–280.CrossRefGoogle Scholar
Smith, D.J., Bursill, L.A. & Wood, G.J. (1985). Non-anomalous high-resolution imaging of crystalline materials. Ultramicroscopy 16, 19–31.CrossRefGoogle Scholar
Takagi, M. & Morimoto, S. (1963). The forbidden 222 electron reflection from germanium. J Phys Soc Jpn 18, 811–819.Google Scholar
Tanaka, M., Sekii, H. & Nagasawa, T. (1983). Space-group determination by dynamic extinction in convergent-beam electron diffraction. Acta Cryst A 39, 825–837.CrossRefGoogle Scholar
Wagner, R.S. & Ellis, W.C. (1964). Vapour-liquid-solid mechanism of single crystal growth. Appl Phys Lett 4, 89–90.CrossRefGoogle Scholar
Weissker, U., Hampel, S., Leonhardt, A. & Büchner, B. (2010). Carbon nanotubes filled with ferromagnetic materials. Materials 3, 4387–4427.CrossRefGoogle ScholarPubMed
Weissker, U., Löffler, M., Wolny, F., Lutz, M.U., Scheerbaum, N., Klingeler, R., Gemming, T., Mühl, T., Leonhardt, A. & Büchner, B. (2009). Perpendicular magnetization of long iron carbide nanowires inside carbon nanotubes due to magnetocrystalline anisotropy. J Appl Phys 106, 054909–054914.CrossRefGoogle Scholar
Wetscher, F., Pippan, R., Sturm, S., Kaufmann, F., Scheu, C. & Dehm, G. (2006). TEM investigations of the structural evolution in a pearlitic steel deformed by high-pressure torsion. Metall Mater Trans A 37, 1963–1968.CrossRefGoogle Scholar
Williams, D.B. & Carter, C.B. (1996). Transmission Electron Microscopy. New York, London: Plenum Press.Google Scholar
Zandbergen, H.W., Andersen, S.J. & Jansen, J. (1997). Structure determination of Mg5Si6 particles in Al by dynamic electron diffraction studies. Science 277, 1221–1225.CrossRefGoogle Scholar