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(a)
(b)
W
L
200 nm
500 nm
2.0 µm
(c)
(d)
100 nm
1 µm
FIGURE 11.15
SEM images of (a) ZnO nanodisks, (b) SnO 2 octahedra, (c) Ag 3 PO 4 rhombic dodecahedrons, and (d) monoclinic
BiVO 4 nanoplates. (a: Adapted with permission from Zeng, J. H., Jin, B. B., Wang, Y. F., Chem. Phys. Lett ., 472, 90.
Copyright 2009, Elsevier. b: Adapted with permission from Han, X. G., Jin, M. S., Xie, S. F., Kuang, Q., Jiang, Z. Y.,
Jiang, Y. Q., Xie, Z. X., Zheng, L. S., Angew. Chem. Int. Ed ., 48, 9180. Copyright 2009, Wiley-VCH. c: Adapted with
permission from Bi, Y. P., Ouyang, S. X., Umezawa, N. J., Cao, Y., Ye, J. H. J. Am. Chem. Soc ., 133, 6490. Copyright
2011, American Chemical Society. d: Adapted with permission from Xi, G. C., Ye, J. H., Chem. Commun ., 46, 1893.
Copyright 2010, Royal Society of Chemistry.)
(a)
(b)
Ti 5c
FIGURE 11.16
(See color insert.) Water adsorption behaviors on anatase (a) TiO 2 {001} vs. (b) {101} surfaces. (Adapted with
permission from Selloni, A., Nat. Mater ., 7, 613. Copyright 2008, Nature Publishing Group.)
11.4.2.2 Reactivity on Crystal Facets
Different surface electronic structures of anatase TiO 2 {001} and {101} facets can also modify
the surface-mediated photocatalytic reactions by driving a divergent diffusion of the pho-
toexcited electrons and holes toward speciic exposed crystal facets. This process results in
the spatial separation of reduction and oxidation sites, subsequently reducing the recom-
bination possibility of photogenerated charge carriers. Recently, a single-molecule imag-
ing and kinetic analysis technology conirmed the directional low of the photoexcited
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