Y. Ishikawa et al.: Preparation of titanium(IV) oxide film on a hard alumite substrate
activity, as shown in Fig. 4(b). The activity of the Al/
Al O /TiO heat treated at 450 °C for 1 h was similar to
that at 550 °C.
ACKNOWLEDGMENTS
2
3
2
The present work was supported by the Sasakawa Sci-
entific Research Grant from The Japan Science Society
and the Sagawa Foundation for Promotion of Frontier
Science.
D. Morphology of the Al/Al O /TiO
2
2
3
Figures 6(a)–6(c) and 6(d)–6(f) show the line profile
of the EPMA elemental distribution in the cross sec-
REFERENCES
tion of the Al/Al O with TiO electrodeposited at 12 V
2
3
2
1. A. Fujishima and K. Honda, Nature 37, 238 (1972).
under various temperatures and their models. The section
where Al overlaps with O in the distribution corresponds
to the alumina film formed on the Al. The thickness of
the alumina film was estimated to be about 25–30 m. Ti
was mainly deposited in the bottom portion of the pores
of the alumina film at 20 °C [Figs. 6(a) and 6(d)]. On the
other hand, the distribution of Ti was shifted to the sur-
face of the alumina film with the temperature of the
electrolyte as shown in Figs. 6(b), 6(c), 6(e), and 6(f).
According to the x-ray photoelectron spectroscopy
2. C.D. Jaeger and A.J. Bar, J. Phys. Chem. 83, 3146 (1979).
3
. H.V. Damme and W.K. Hall, J. Am. Chem. Soc. 101, 4373
1979).
. S. Sato and J.M. White, Chem. Phys. Lett. 72, 83 (1980).
(
4
5
. M.V. Rao, K. Rejeswar, V.R.D. Vernecker and J. DuBow,
J. Phys. Chem. 84, 1987 (1980).
6. S. Sato and J.M. White, J. Phys. Chem. 85, 592 (1981).
7
8
. S.N. Frank and A.J. Bard, J. Am. Chem. Soc. 99, 303 (1977).
. T. Inoue, A. Fujishima, S. Kornishi, and K. Honda, Nature 277,
637 (1979).
9. B. Kraeutler and A.J. Bard, J. Am. Chem. Soc. 100, 2239 (1978).
1
1
1
0. H. Yoneyama, Y. Takao, H. Tamura, and A.J. Bard, J. Phys.
Chem. 87, 1417 (1983).
1. J.C.S. Wong, A. Linsebigler, G. Lu, J. Fan, and J.T. Yates, Jr.,
J. Phys. Chem. 99, 335 (1995).
2. Z. Goren, I. Willner, A.J. Nelson, and A.J. Frank, J. Phys. Chem.
(
XPS) measurement of the surface of the Al/Al O /TiO ,
2 3 2
TiO on surface of the Al/Al O substrate was detected
2
2 3
for the deposition at 70 and 90 °C, but not at 50 °C.
Most likely, the hydration of alumina (denoted as
94, 3784 (1990).
Al O ⅐ nH O) might be formed at the bottom of the
2
3
2
13. H. Aritani, N. Akasaka, T. Tanaka, T. Funabiki, S. Yoshida,
pores of the alumina film by immersion in the high-
temperature aqueous solution. Therefore, the pores of
the alumina film were sealed with the produced hydrated
alumina at high temperatures, leading to the change in
H. Gotoh, and Y. Okamoto, J. Chem. Soc., Faraday Trans. 92,
2625 (1996).
1
1
4. I. Sopyan, M. Watanabe, S. Murasawa, K. Hashimoto, and
A. Fujishima. J. Photochem. Photobiol. A 98, 79 (1996).
5. A.J. Nozik and R. Memming, J. Phys. Chem. 100, 13061 (1996).
16. C. Anderson and A.J. Bard, J. Phys. Chem. 99, 9882 (1995).
17. H. Yamashita, Y. Ichihashi, M. Harada, G. Stewart, M.A. Fox,
and M. Anpo, J. Catal. 158, 97 (1996).
the deposited TiO location as shown in Fig. 6(f). For the
2
precipitation at 20 °C, Ti was not detected because
the amount of the deposited TiO was quite low. The
2
1
8. N. Negishi, T. Iyada, K. Hashimoto, and A. Fujishima, Chem.
differences in the Ti distribution were not observed at 50
Lett. 841 (1995).
and 90 °C, whether the electrolysis was carried out or not.
1
9. K. Hashimoto and A. Fujishima, TiO Photocatalysis (CMC, To-
3
6
2
In a previous paper, an improvement in the adhesion
between the deposited TiO and the Al/Al O substrate
kyo, Japan, 1998), pp. 94, 119.
20. G. Dagan and M. Tomikiewicz, J. Phys. Chem. 97, 12651 (1993).
1. A. Sclafani, L. Palmisano, and M. Schiavello, J. Phys. Chem. 94,
2
2 3
2
2
2
2
2
2
2
2
was accomplished by the presence of the deposited TiO2
in the pores of the alumina film. Consequently, the
829 (1990).
2. B. Ohtani, R.M. Bowman, Jr., G.P. Colombo, H. Kominami,
H. Noguchi, and K. Uosaki, Chem. Lett. 579 (1998).
3. N.B. Jackson, C.M. Wang, Z. Luo, J. Schwitzgebel, J.G. Ekerdt,
J.R. Brock, and A. Heller, J. Electrochem. Soc. 138, 3660 (1991).
4. H. Matsubara, M. Takada, S. Koyama, K. Hashimoto, and
A. Fujishima, Chem. Lett. 767 (1995).
TiO deposition in the pore of the alumina film at tem-
2
peratures less than about 70 °C is also preferable for the
strong adhesion between the TiO and the Al/Al O sub-
2
2 3
strate. In practice, most of the TiO deposited at tem-
2
peratures higher than 70 °C was removed from the Al/
Al O substrate, but not for that at 50 °C, based on a
5. S. Deki, Y. Aoi, O. Hiroi, and A. Kajinamim, Chem. Lett. 433
2
3
(
1996).
Scotch tape adhesion peel test.
6. H. Miyoshi, S. Nippa, H. Uchida, H. Mori, and H. Yoneyama,
Bull. Chem. Soc. Jpn. 63, 3380 (1990).
7. K. Ikeda, H. Sakai, R. Baba, K. Hashimoto, and A. Fujishima,
J. Phys. Chem. B 101, 2617 (1997).
8. L. Kavan, B. O’Regan, A. Kay, and M. Gr a¨ tzel, J. Electroanal.
Chem. 346, 291 (1993).
In conclusion, an improvement in the photocatalytic
activity of the Al/Al O /TiO was accomplished by in-
2
3
2
creasing the temperature of the TiO deposition. How-
2
ever, the adhesion strength between the deposited TiO2
and the Al/Al O substrate was insufficient for the
2
3
29. B. Ohtani, Y. Ogawa, and S. Nishimoto, J. Phys. Chem. B 101,
TiO deposition at 90 °C because the deposited TiO
3746 (1997).
2
2
3
0. I. Mita, K. Kuroda, K. Suzuki, Y. Muramatsu, S. Nemoto, and
M. Yamada, in Handbook of Aluminum Surface Treatment (Light
Metal Publishing, Tokyo, Japan, 1980), pp. 987, 1200.
1. T. Sato, Trans. Inst. Met. Finish. 60, 25 (1982).
2. A.P. Li, F. M u¨ ller, A. Birner, K. Nielsch, and U. G o¨ sele, J. Appl.
Phys. 84, 6023 (1998).
mainly existed on the surface of the Al/Al O substrate.
2
3
The Al/Al O /TiO prepared at 50 °C, which showed a
2
3
2
relatively high photocatalytic activity, was the most pref-
erable for practical use because most of the deposited
3
3
TiO existed in pores of the alumina film.
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