Page 226 - Book Hosokawa Nanoparticle Technology Handbook

FUNDAMENTALS CH. 4 CONTROL OF NANOSTRUCTURE OF MATERIALS
energy-generation as well as photocatalytic applica-
tions. In future, new performances may be found by
examining various ion-species as dopants.
Since the finding of titania nanotubes 10 years ago,
numerous works for clarifying the formation mecha-
nism have been carried out.

References
[1] S. Iijima: Nature, 354, 56–59 (1991).
[2] T. Kasuga, M. Hiramatu, M. Hirano, A. Hoson and
K. Oyamada: J. Mater. Res., 12, 607–609 (1997).
[3] Y. Suzuki, T. Sekino: Mater. Integration, 18, 3–10
(2005).
[4] P. Hoyer: Langmuir, 12, 1411–1413 (1996).
[5] P. Hoyer: Adv. Mater, 8, 857–859 (1996).
[6] H. Imai, Y. Takai, K. Shimizu, M. Matsuda and
H. Hirashima: J. Mater. Chem., 9, 2971–2972
(1999).
[7] M. Adachi, Y. Murata, M. Harada and S. Yoshikawa:
Chem. Lett., 942–943 (2000).
[8] A. Michailowski, D. Almawlawi, G.S. Chemg and
M. Moskovits: Chem. Phys. Lett., 349, 1–5 (2001).
[9] R.A. Caruso, J.H. Schattka and A. Greiner: Adv.
Figure 4.3.18 Mater., 13, 1577–1579 (2001).
TEM image of TiO powders treated with 10 M aqueous [10] D. Gong, C.A. Grimes, O.K. Varghese, W. Hu,
2
o
NaOH at 110 C for 20 hours.
R.S. Singh, Z. Chen and E.C. Dickey: J. Mater. Res.,
16, 3331–3334 (2001).
[11] O.K. Varghese, D. Gong, M. Paulose, K.G. Ong,
that BaTiO and/or SrTiO were obtained by refluxing E.C. Dickey and C.A. Grimes: Adv. Mater., 15,
3
3
titania nanotubes in an inert atmosphere with Ba(OH) 624–627 (2003).
and/or SrCl . [12] J. Sun, L. Gao and Q.H. Zhamg: J. Mater. Sci. Lett.,
2
Sekino et al. prepared metal (Nb, V, Cr, Mn, Co)- 22, 339 (2003); J. Sun, L. Gao, Q.H. Zhamg and
doped titania nanotubes for improving photocatalytic A. Iwasa: Carbon, 42, 895–899 (2004).
activities. Wang et al. reported the preparation of [13] H. Shin, D.K. Jeong, J.G. Lee, M.M Sung and
RuO /TiO nanotube composites and the electro- J.Y. Kim: Adv. Mater., 16, 1197–1200 (2004).
2
2
chemical properties. [14] T. Kasuga, M. Hiramatu, A. Hoson, T. Sekino and
Kasuga reported that titania nanotubes show excel-
lent ion adsorption activities and contain a large K. Niihara: Langmuir, 14, 3160–3163 (1998).
amount of hydroxyl group in comparison with raw [15] T. Kasuga, M. Hiramatu, A. Hoson, T. Sekino and
titania powders. These characteristic properties lead K. Niihara: Adv. Mater., 11, 1307–1311 (1999).
to new performance such as biocompatibility and pro- [16] W. Wang, O.K. Varghese, M. Paulose and
ton conduction [23]. C.A. Grimes: J. Mater. Res., 19, 417–422 (2004).
Ca 2 ion-doped titania nanotubes are expected to [17] R. Ma, K. Fukuda, T. Sasaki, M. Osada and Y. Bando:
be used as biomaterials, and oxyacid-doped titania J. Phys. Chem., B.109, 6210–6214 (2005).
nanotubes are expected to be applied to solid elec- [18] D.-S. Seo, J.-K. Lee and H. Kim: J. Cryst. Growth,
trolytes. Ca-titania nanotubes have good bioactivity 229, 428 (2001).
for bone regeneration in living body [24]. The [19] Q. Chen, G.H. Du, S. Zhang and L.-M. Peng: Acta
oxyacid-doped titania nanotubes exhibit high proton Cryst., B 58, 587–593 (2002).
o
conductivities at temperatures of 100 C or higher.
Therefore, they are expected to lead to the develop- [20] B.D. Yao, Y.F. Chen, X.Y. Zhang, W.F. Zhang,
ment of technologies for electrolytic films used in Z.Y. Yang and N. Wang: Appl. Phys. Lett., 82,
fuel cells. 281–283 (2003).
These nanotubes are expected to be used as [21] Q. Chen, L.-M. Peng, W.Z. Zhou and G. Du: Adv.
applications in the fields of medicine and/or Mater., 14, 1208–1211 (2002).
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