Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-25T17:41:10.048Z Has data issue: false hasContentIssue false

Orientation Dependence of the Photochemical Reactivity of BaTi4O9

Published online by Cambridge University Press:  11 February 2011

Jennifer L. Giocondi
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213–3890, U.S.A.
Shahrzad Samadzadeh
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213–3890, U.S.A.
Gregory S. Rohrer
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213–3890, U.S.A.
Get access

Abstract

BaTi4O9 is a photocatalyst with a pentagonal prism tunnel structure. It has been hypothesized that the tunnels promote the separation of photogenerated carriers and, therefore, lead to the spatial separation of oxidation and reduction half reactions. This hypothesis has been tested by observing the distribution of reduced and oxidized reaction products on BaTi4O9 surfaces over a wide range of orientations. The surface orientations were determined by electron backscattered diffraction and atomic force microscopy was used to examine the structure of the surface both before and after the deposition of reaction products. Reduction products (Ag0) are distributed uniformly. The distribution of oxidation products (PbO2) is also not correlated to the surface orientation or to the orientation of the tunnels with respect to the surface. Based on these observations, we conclude that the tunnels in this structure do not separate photogenerated charge carriers and that this mechanism is not responsible for this compound's relatively high photocatalytic activity.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Fujishima, A. and Honda, K., Nature 238, 37 (1972).Google Scholar
[2] Domen, K., in Surface Photochemistry, edited by Anpo, M., (J. Wiley and Sons, Chichester, England, 1996) p. 1.Google Scholar
[3] Takata, T., Furumi, Y., Shinohara, K., Tanaka, A., Hara, M., Kondo, J.N., and Domen, K., Chem. Mat. 9, 1063 (1997).Google Scholar
[4] Hwang, D.W., Kim, H.G., Kim, J., Cha, K.Y., Kim, Y.G., and Lee, J.S., J. Catalysis 193, 40 (2000).Google Scholar
[5] Inoue, Y., Kubokawa, T., and Sato, K., J. Phys. Chem. 95, 4059 (1991).Google Scholar
[6] Ogura, S., Kohno, M., Sato, K., and Inoue, Y., Phys. Chem. Chem. Phys. 1, 179 (1999).Google Scholar
[7] Inoue, Y., Niiyama, T., Asai, Y., and Sato, K., J. Chem. Soc., Chem. Commun. 1992, 579.Google Scholar
[8] Kohno, M., Ogura, S., Sato, K., and Inoue, Y., J. Chem. Soc., Faraday Trans. 93 (14), 2433 (1997).Google Scholar
[9] Kohno, M., Ogura, S., Sato, K., and Inoue, Y., in Studies in Surface Science and Catalysis, Vol. 101, edited by Hightower, J.W., Delgass, W.N., Iglesia, E., and Bell, A.T., (Elsevier Science, New York, 1996) p. 143.Google Scholar
[10] Tillmanns, E. and Baur, W.H., Acta Crystallogr., Sect. B 26, 1645 (1970).Google Scholar
[11] Torres, J. and Cervera-March, S., Chem. Eng. Sci. 47, 3857 (1992).Google Scholar
[12] Herrmann, J.-M., Disdier, J., and Pichat, P., J. Catalysis 113 (1), 72 (1988).Google Scholar
[13] Giocondi, J.L. and Rohrer, G.S., J. Phys. Chem. B 105 (35), 8275 (2001).Google Scholar
[14] Lowekamp, J.B., Rohrer, G.S., Morris Hotsenpiller, P.A., Bolt, J.D., and Farneth, W.D., J. Phys. Chem. B 102 (38), 7323 (1998).Google Scholar
[15] Kohno, M., Ogura, S., Sato, K., and Inoue, Y., J. Chem. Soc., Faraday Trans. 94 (1), 89 (1998).Google Scholar
[16] Inoue, Y., Hayashi, O., and Sato, K., J. Chem. Soc., Faraday Trans. 86 (12), 2277 (1990).Google Scholar
[17] Giocondi, J.L. and Rohrer, G.S., Chem. Mater. 13 (2), 241 (2001).Google Scholar
[18] Giocondi, J.L. and Rohrer, G.S., J. Amer. Ceram. Soc., submitted.Google Scholar