Investigation of structural iron species in Fe-mesoporous silicas by spectroscopic techniques

(Note: The full text of this document is currently only available in the PDF Version )

A. Tuel, I. Arcon and J. M. M. Millet


Abstract

A series of iron-containing mesoporous silicas (Fe-HMS) with Fe contents up to 5.7 wt.% have been prepared at room temperature using the neutral hexadecylamine as surfactant molecule. Characterization of these materials by a variety of spectroscopic techniques, including EXAFS, EPR, Mössbauer and UV–Vis spectroscopies, suggests that Fe species are tetrahedrally coordinated in as-made materials. Tetrahedra are highly distorted with two long and two short Fe–O bond distances due to hydrogen-bonding type interactions with the organic molecules. Removal of the amines by solvent extraction does not modify the chemical environment around the Fe species. Subsequent calcination leads to mainly 3-coordinated Fe species, readily converting to 4-coordinated species in the presence of water. The solvent extraction appears to be a key step to prevent the formation of extraframework iron oxide species, which are formed in large amount when the surfactant is directly removed from as-made materials by calcination in air at high temperature.


References

  1. C. T. Kresge, M. E. Leonowicz, W. J. Roth, J. C. Vartuli and J. S. Beck, Nature (London), 1992, 359, 710 CrossRef CAS.
  2. J. S. Beck, J. C. Vartuli, W. J. Roth, M. E. Leonowicz, C. T. Kresge, K. D. Schmitt, C. T.-W. Chu, D. H. Olson, E. W. Sheppard, S. B. McCullen, J. B. Higgins and J. L. Schlenker, J. Am. Chem. Soc., 1992, 114, 10834 CrossRef CAS.
  3. C. Y. Chen, S. L. Burkett, H. X. Li and M. E. Davis, Microporous Mater., 1997, 2, 27 CrossRef CAS.
  4. A. Firouzi, A. Monnier, L. M. Bull, T. Besier, P. Sieger, Q. Huo, S. A. Walker, J. A. Zasadzinski, C. Glinka, J. Nicol, D. Margolese, G. D. Stucky and B. F. Chmelka, Science, 1995, 267, 1138 CrossRef CAS.
  5. J. C. Vartuli, K. D. Schmitt, C. T. Kresge, W. J. Roth, M. E. Leonowicz, S. B. McCullen, S. D. Hellring, J. S. Beck, J. L. Schlenker, D. H. Olson and E. W. Sheppard, Stud. Surf. Sci. Catal., 1994, 84, 53 CAS.
  6. P. T. Tanev, M. Chibwe and T. J. Pinnavaia, Nature (London), 1994, 368, 321 CrossRef CAS.
  7. P. T. Tavev and T. J. Pinnavaia, Science, 1995, 267, 865 CrossRef CAS.
  8. A. Sayari, Chem. Mater., 1996, 8, 1840 CrossRef CAS.
  9. A. Corma, Chem. Rev., 1997, 97, 2373 CrossRef CAS.
  10. A. Tuel, Microporous Mesoporous Mater., in the press Search PubMed.
  11. S. Gontier and A. Tuel, Zeolites, 1995, 15, 601 CrossRef CAS.
  12. S. Gontier and A. Tuel, Microporous Mater., 1995, 5, 161 CrossRef CAS.
  13. A. Tuel and S. Gontier, Chem. Mater., 1996, 8, 114 CrossRef CAS.
  14. S. Gontier and A. Tuel, Appl. Catal. A: General, 1996, 143, 125 CrossRef CAS.
  15. W. Zhang, M. Fröba, J. Wang, P. T. Tanev, J. Wong and T. J. Pinnavaia, J. Am. Chem. Soc., 1996, 118, 9164 CrossRef CAS.
  16. Z. Luan, J. Xu, H. He, J. Klinowski and L. Kevan, J. Phys. Chem., 1996, 100, 19595 CrossRef CAS.
  17. J. S. Reddy, P. Liu and A. Sayari, Appl. Catal. A. General, 1996, 148, 7 CrossRef.
  18. T. M. Abdel-Fattah and T. J. Pinnavaia, J. Chem. Soc., Chem. Commun., 1996, 665 RSC.
  19. M. Morey, A. Davidson and G. D. Stucky, Microporous Mater., 1996, 6, 99 CrossRef CAS.
  20. W. Zhang and T. J. Pinnavaia, Catal. Lett., 1996, 38, 261 CrossRef CAS.
  21. N.-Y. He, S.-L. Bao and Q.-H. Xu, Stud. Surf. Sci. Catal., 1997, 105, 85.
  22. B. Echchahed, A. Moen, D. Nicolson and L. Bonneviot, Chem. Mater., 1997, 9, 1716 CrossRef.
  23. Z. Luan, C.-F. Chen, W. Zhou and J. Klinowski, J. Phys. Chem., 1995, 99, 1018 CrossRef CAS.
  24. C.-F. Cheng and J. Klinowski, J. Chem. Soc., Faraday Trans., 1996, 92, 289 RSC.
  25. S. Liu, H. He, Z. Luan and J. Klinowski, J. Chem. Soc., Faraday Trans., 1996, 92, 2011 RSC.
  26. A. Sayari, I. Moudrakowski, C. Danumah, C. I. Ratcliffe, J. A. Ripmester and K. F. Preston, J. Phys. Chem., 1995, 99, 16373 CrossRef CAS.
  27. J. Patarin, M. H. Tuilier, J. Durr and H. Kessler, Zeolites, 1992, 12, 70 CAS.
  28. A. Meagher, V. Nair and R. Szostak, Zeolites, 1998, 18, 3 Search PubMed.
  29. S. Bordiga, R. Buzzoni, F. Geobaldo, C. Lamberti, E. Giamello, A. Zecchnina, G. Leofanti, G. Petrini, G. Tozzola and G. Vlaic, J. Catal., 1996, 158, 486 CrossRef CAS.
  30. D. Goldfarb, M. Bernardo, K. G. Strohmaier, D. E. W. Vaughan and H. Thomann, J. Am. Chem. Soc., 1994, 116, 6344 CrossRef.
  31. G. Calis, P. Frenken, E. de Boer, A. Swolfs and M. A. Hefni, Zeolites, 1987, 7, 319 CAS.
  32. K. Lazar, G. Borbely and H. Beyer, Zeolites, 1991, 11, 214 CAS.
  33. R. Kumar, S. K. Date, E. Bill and A. Trautwein, Zeolites, 1991, 11, 211 CAS.
  34. P. N. Joshi, S. V. Awate and V. P. Shiralkar, J. Phys. Chem., 1993, 97, 9749 CrossRef CAS.
  35. A. J. Chandwadkar, S. K. Date, E. Bill and A. Trautwein, Zeolites, 1992, 12, 180 CAS.
  36. D. H. Lin, G. Coudurier and J. C. Vedrine, Stud. Surf. Sci. Catal., 1989, 49, 1431.
  37. E. A. Stern, M. Newville, B. Ravel, Y. Yacobi and D. Haskel, Physica B, 1995, 208 & 209, 117 CrossRef.
  38. J. J. Rehr, R. C. Albers and S. I. Zabinsky, Phys. Rev. Lett., 1992, 69, 3397 CrossRef CAS.
  39. A. Goiffon, J. C. Dumas and E. Philippot, Rev. Chim. Minérale, 1986, 23, 99 Search PubMed.
  40. M. Roy, S. J. Gurman and G. van Dorssen, J. Phys. IV France, Coll. C2, Suppl. J. Phys. Il d'Avril 1997, 1997, C2–151 Search PubMed.
  41. A. Di Chicco, Physica B, 1995, 208 & 209, 125 CrossRef.
  42. L. E. Iton, R. B. Beal and D. T. Hodul, J. Mol. Catal., 1983, 21, 151 CrossRef CAS.
  43. B. N. Figgis, Introduction to Ligand Fields, Wiley, New York, 1966 Search PubMed.
  44. P. Ratnasamy and R. Kumar, Catal. Today, 1991, 9, 341 CrossRef.
Click here to see how this site uses Cookies. View our privacy policy here.