Advertisement

Journal of Materials Science

, Volume 29, Issue 23, pp 6175–6180 | Cite as

Synthesis of carbon-iron(II) oxide layer on the surface of magnetite and its reactivity with H2O for hydrogen generation

  • Y. Tamaura
  • K. Akanuma
  • N. Hasegawa
  • M. Tsuji
Article

Abstract

Synthesis of a carbon-iron(II) oxide layer on the surface of magnetite and its reactivity with H2O for hydrogen generation reaction have been studied. X-ray diffractometry and chemical analysis showed that the carbon-bearing magnetite synthesized by the carbon-deposition reaction from CO2 gas with the hydrogen-reduced magnetite, was magnetite with a carbon-iron(II) oxide layer (CIO layer-M; M is stoichiometric magnetite) represented by (Fe3O4)1−δ (Fe3O3)δCτ. The TG-MS spectra also showed the evidence for the formation of the CIO layer on the bulk stoichiometric magnetite. Some amorphous phase was formed in the CIO layer during the activation step (in vacuo at 300 °C for 30 min). This amorphous phase reacted with H2O and evolved H2 gas at 350 °C. This H2 generation reaction resulted in the oxidation of the CIO layer into γ-Fe2O3 component and the release of a part of carbon in the CIO layer as CO2. The X-ray diffractometry and Mössbauer spectroscopy indicated that the solid solution of Fe3O4-γ-Fe2O3 was formed in the solid phase after the H2 generation reaction. This shows the cation movement in the B site of the bulk magnetite of the activated CIO layer-M during the H2 generation reaction. The TG-MS spectra also supported the above estimation.

Keywords

Solid Solution Fe3O4 Magnetite Oxide Layer Amorphous Phase 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    L. S. Darken and R. W. Gurry, J. Am. Chem. Soc. 67 (1945) 1398.CrossRefGoogle Scholar
  2. 2.
    Idem, ibid. 68 (1946) 798.CrossRefGoogle Scholar
  3. 3.
    J. Smiltens, ibid. 79 (1957) 4877.CrossRefGoogle Scholar
  4. 4.
    Idem, ibid. 79 (1957) 4881.CrossRefGoogle Scholar
  5. 5.
    O. N. Salmon, J. Phys. Chem. 65 (1961) 550.CrossRefGoogle Scholar
  6. 6.
    R. Dieckmann, Ber. Bunsenges. Phys. Chem. 86 (1982) 112.CrossRefGoogle Scholar
  7. 7.
    Y. Tamaura and M. Tabata, Nature (Lond.) 346 (1990) 255.CrossRefGoogle Scholar
  8. 8.
    Y. Tamaura, in “Proceedings of the International Symposium on Chemical Fixation of Carbon Dioxide”, Nagoya, December 1991, edited by K. Ito (The Chemical Society of Japan, 1991) p. 167.Google Scholar
  9. 9.
    K. Nishizawa, T. Kodama, M. Tabata, T. Yoshida, M. Tsuji and Y. Tamaura, J. Chem. Soc. Faraday Trans. 88 (1992) 2771.CrossRefGoogle Scholar
  10. 10.
    K. Akanuma, K. Nishizawa, T. Kodama, M. Tabata, K. Mimori, T. Yoshida, M. Tsuji and Y. Tamaura, J. Mater. Sci 28 (1993) 860.CrossRefGoogle Scholar
  11. 11.
    Y. Tamaura, in “Proceedings of the Sixth International Conference on Ferrites” (ICF 6), Tokyo and Kyoto, September 1992, edited by T. Yamaguchi and M. Abe (The Japan Society of Powder and Powder Metallurgy, 1992) p. 195.Google Scholar
  12. 12.
    K. Akanuma, K. Nishizawa, T. Kodama, M. Tabata, T. Yoshida and Y. Tamaura, ibid., p. 229.Google Scholar
  13. 13.
    K. Nishizawa, T. Kodama, M. Tabata, T. Yoshida and Y. Tamaura, ibid. p. 239.Google Scholar
  14. 14.
    M. Tabata, T. Kodama, K. Akanuma, K. Nishizawa, T. Yoshida and Y. Tamaura, ibid., p. 246.Google Scholar
  15. 15.
    M. Tabata, Y. Nishida, T. Kodama, K. Mimori, T. Yoshida and Y. Tamaura, J. Mater. Sci. 28 (1993) 971.CrossRefGoogle Scholar
  16. 16.
    K. Akanuma, M. Tabata, N. Hasegawa, M. Tsuji, Y. Tamaura, Y. Nakahara and S. Hoshino, J. Mater. Chem. 3 (1993) 943.CrossRefGoogle Scholar
  17. 17.
    Y. Tamaura, S. Mechaimonchit and T. Katsura, J. Inorg. Nucl. Chem. 43 (1980) 671.CrossRefGoogle Scholar
  18. 18.
    T. Katsura, Y. Tamaura and G. S. Chyo, Bull. Chem. Soc. Jpn 52 (1979) 96.CrossRefGoogle Scholar
  19. 19.
    Y. Tamaura, P. V. Buduan and T. Katsura, J. Chem. Soc. Dalton Trans. (1981) 1807.Google Scholar
  20. 20.
    M. Kiyama, Bull. Chem. Soc. Jpn 47 (1974) 1646.CrossRefGoogle Scholar
  21. 21.
    JCPDS cards 19-629 (Joint Committee on Powder Diffraction Standards, Swarthmore, PA, 1989).Google Scholar
  22. 22.
    Y. Tamaura, T. Kodama and T. Itoh, J. Am. Ceram. Soc. 73 (1990) 3539.CrossRefGoogle Scholar
  23. 23.
    K. Kodama, J. Mater. Chem. 2 (1992) 525.CrossRefGoogle Scholar
  24. 24.
    I. Iwasaki, T. Katsura, T. Ozawa, M. Yoshida, M. Mashima, H. Haramura and B. Iwasaki, Bull. Volcanol. Soc. Jpn Ser. II 5 (1960) 9.Google Scholar

Copyright information

© Chapman & Hall 1994

Authors and Affiliations

  • Y. Tamaura
    • 1
  • K. Akanuma
    • 1
  • N. Hasegawa
    • 1
  • M. Tsuji
    • 1
  1. 1.Department of Chemistry, Research Center for Carbon Recycling and UtilizationTokyo Institute of TechnologyTokyoJapan

Personalised recommendations