Photooxidation of M(CO)₆ (M=Mo, W) adsorbed on TiO₂

Abstract

Photooxidation of M(CO)₆ (M=Mo, W) adsorbed on TiO₂ has been conducted from a viewpoint of the kinetics and mechanism of the reaction and the photocatalytic effect of TiO₂. The reaction rate was first order with respect to the surface concentration of M(CO)₆ and zero order with respect to oxygen pressure. The photocatalytic effect of TiO₂ was suggested by the fact that the reaction rate of the W(CO)₆/TiO₂ system was considerably greater than that of W(CO)₆/NaY zeolite. The rate constant strongly depended on the TiO₂ employed and was delineated to a direct-allowed band-gap of the TiO₂. The photocatalytic effects of TiO₂ are tentatively suggested to result from a strongly enhanced decarbonylation of M(CO)₆ by photoinduced valence band holes, followed by rapid reactions with anionic surface oxygen species.

References

1. H. D. Gafney, Stud. Surf. Sci. Catal., 1989, 47, 272.
2. R. L. Jackson and M. R. Thrusheim, J. Am. Chem. Soc., 1982, 104, 6590.
3. M. S. Darsillo, H. D. Gafney and M. S. Paqutte, J. Am. Chem. Soc., 1987, 109, 3275.
4. R. L. Jackson, Stud. Surf. Sci. Catal., 1989, 47, 288.
5. T. Ohmori and S. Sato, J. Photochem. Photobiol. A: Chem., 1992, 64, 201.
6. N. Bottka, P. J. Walsh and R. Z. Dalbey, J. Appl. Phys., 1983, 54, 1104.
7. J. R. Swanson, C. M. Friend and Y. J. Chabal, J. Chem. Phys., 1987, 87, 5028.
8. Y. Ukis, S. Sato and T. Ohmori, Appl. Organomet. Chem., 1991, 5, 243.
9. K. A. Singmaster, F. A. Houle and R. Wilson, J. Phys. Chem., 1990, 94, 6864.
10. F. A. Houle and K. A. Singmaster, J. Phys. Chem., 1992, 96, 10 425.
11. J. R. Swanson, F. A. Flitsch and C. M. Friend, Surf. Sci., 1990, 226, 147.
12. J. R. Swanson, F. A. Flitsch and C. M. Friend, Surf. Sci., 1989, 215, L293.
13. R. C. Simon, H. D. Gafney and D. L. Morse, Inorg. Chem., 1985, 24, 2565.
14. R. C. Simon, E. A. Mendova and H. D. Gafney, Inorg. Chem., 1988, 27, 2733.
15. G. A. Ozin, P. A. Prokorowicz and S. Ozkar, J. Am. Chem. Soc., 1992, 114, 8953.
16. K. Moller, T. Bein, S. Ozkar and G. A. Ozin, J. Phys. Chem., 1991, 95, 5276.
17. G. A. Ozin and S. Ozkar, J. Phys. Chem., 1990, 94, 7556.
18. R. Jelinek, S. Ozkar and G. A. Ozin, J. Phys. Chem., 1992, 96, 5949.
19. Y. Okamoto, Y. Kobayashi and T. Imanaka, Catal. Lett., 1993, 20, 49.
20. P. N. Gonzalez, M. A. Villa Garcia and A. Brenner, J. Catal., 1989, 118, 360.
21. Y. Takita, Y. Moro-oka and A. Ozaki, J. Catal., 1970, 17, 132.
22. Y. Takita, A. Ozaki and Y. Moro-oka, J. Catal., 1972, 27, 185.
23. A. L. Liesebigler, L. Guangquan and J. T. Yates, Jr., Chem. Rev., 1995, 95, 735.
24. M. R. Hoffmann, S. T. Martin, W. Choi and D. W. Barnemann, Chem. Rev., 1995, 95, 69.
25. Y. Murakami, Preparation of Catalysts III, ed. G. Poncelet, P. Grange and P. A. Jacobs, Elsevier, Amsterdam, 1993, p. 775.
26. Reference Catalyst Committee of Catalysis Society of Japan, Shokubai (Catalysts & Catalysis), 1996, 38, 370(in Japanese).
27. B. Karvaly and I. Hevesi, Z. Naturforsch. A, 1971, 26, 245.
28. P. Gallezot, Catalysis, Science and Technology, ed. J. R. Anderson and M. Boudard, Springer-Verlag, Berlin, 1984, vol. 5, p. 221.
29. J. A. Crayston, M. J. Almond, A. J. Downs, M. Poliakoff and J. J. Turner, Inorg. Chem., 1984, 23, 3051.
30. M. J. Almond, J. A. Crayton, A. J. Downs, M. Poliakoff and J. J. Turner, Inorg. Chem., 1986, 25, 19.
31. M. J. Almond and A. J. Downs, J. Chem. Soc., Dalton Trans., 1988, 809.
32. M. J. Almond, Chem. Soc. Rev., 1994, 309.
33. Y. Okamoto, unpublished work.
34. A. W. Ehlers and G. Frenking, J. Chem. Soc., Chem. Commun., 1993, 1709.
35. J. Li, G. Schreckenbach and T. Ziegler, J. Phys. Chem., 1994, 98, 4838.
36. H. Hattori, Chem. Rev., 1995, 95, 537.
37. M. Laniecki and R. L. Burwell, Jr., J. Colloid Interf. Sci., 1980, 75, 95.
38. T. L. Brown, J. Mol. Catal., 1981, 12, 41.
39. E. Guglielminotti and A. Zecchina, J. Chim. Phys., 1981, 78, 891.
40. G. J. Gajda, R. H. Gruggs and W. H. Weinberg, J. Am. Chem. Soc., 1987, 109, 66.
41. Y. Masuyama, Y. Tomatsu, K. Ishida, Y. Kurusu and K. Segawa, J. Catal., 1988, 114, 347.
42. W. N. Delgass, G. L. Haller, R. Kellerman and J. H. Lunsford, Spectroscopy in Heterogeneous Catalysis, Academic Press, New York, 1979, ch. 4.
43. P. A. Cox, Transition Metal Oxides, Oxford Science Publications, Oxford, 1992, p. 105.
44. J. Tauc, R. Grigorovici and A. Vancu, Phys. Status Solidi, 1996, 15, 627.
45. E. A. Davis and N. F. Mott, Philos. Mag., 1970, 22, 903.
46. F. Arntz and Y. Yacoby, Phys. Rev. Lett., 1966, 17, 867.
47. K. Vos and H. J. Krusemeyer, Solid State Commun., 1974, 15, 949.
48. N. Daude, C. Gout and G. Jouanin, Phys. Rev. B, 1977, 15, 3229.
49. J. Pascual, J. Camassel and H. Mathieu, Phys. Rev. B, 1978, 18, 5606.
50. A. Frova, P. J. Body and Y. S. Chen, Phys. Rev., 1967, 157, 700.
51. H. Yamashita, H. Nishiguchi, N. Kamada, M. Anpo, Y. Teraoka, H. Hatano, S. Ehara, K. Kikui, L. Palmisano, A. Sclafani, M. Schiavello and M. A. Fox, Res. Chem. Intermed., 1994, 20, 815.
52. A. Gonzalez-Elipre, G. Munuera and J. Soria, J. Chem. Soc., Faraday Trans. 1, 1979, 75, 749.