Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-05T01:51:07.837Z Has data issue: false hasContentIssue false

Competitive Adsorption of O2 and H2O at the Neutral and Defective SnO2 (110) Surface

Published online by Cambridge University Press:  18 March 2011

Ben Slater
Affiliation:
Davy Faraday Research Laboratory, The Royal Institution of Great Britain, 21 Albemarle St., London, W1S 4BS, U.K.
C. Richard A. Catlow
Affiliation:
Davy Faraday Research Laboratory, The Royal Institution of Great Britain, 21 Albemarle St., London, W1S 4BS, U.K.
David E. Williams
Affiliation:
Department of Chemistry, University College London, 20 Gordon St, London, WC1H OAJ, U.K.
A. Marshall Stoneham
Affiliation:
Department of Physics and Astronomy, University College London, Gower St, London, WC1E 6BT, U.K.
Get access

Abstract

Using first principles techniques we have examined the relative physisorption/chemisorption energetics of neutral molecular water and oxygen at the most thermodynamically stable surface (110) of tin dioxide. We find that water binds more strongly to the perfect surface at 5 co- ordinate tin sites than oxygen. However, binding of both water and oxygen at bridging oxygen vacancies in the defective surface is comparable. In the context of gas-sensing behaviour at moderate temperatures (∼300K), we propose that the Mars and van Krevelen [1] re-oxidation reaction will slow when the partial pressure of water is high, since the number of favourable adsorption sites will effectively decrease. In addition, one would expect that the surface conductivity will increase, since the re-oxidation reaction will be hindered.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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

1. Mars, P. and Krevelen, D. W. van, Chem. Eng. Sci, 41, 3 (1954).Google Scholar
2. Williams, D. E. and Pratt, K. F. E., J. Chem. Soc. Faraday Trans., 94 (23) 34933500 (1998).Google Scholar
3. Williams, D. E., in Solid State Gas Sensing, ed. Moseley, P.T.; Tofield, B.C., Adam Hilger, Bristol, (1987).Google Scholar
4. Manassidis, I., Goniakowski, J., Kantorovich, L. N. and Gillan, M. J., Surf. Sci., 339, 258271 (1995).Google Scholar
5. Goniakowski, J. and Gillan, M. J., Surf. Sci., 1996, 350, 145158 (1996).Google Scholar
6. Goniakowski, J., Holender, J. M., Kantorovich, L.N., Gillan, M. J. and White, J. A., Phys. Rev. B, 53(3), 957 (1996).Google Scholar
7. Oviedo, J. and Gillan, M. J., Surf. Sci., 467: (1-3) 3548 (2000).Google Scholar
8. Lindan, P. J., Chem. Phys. Lett., 328, 325329 (2000).Google Scholar
9. Slater, B., Catlow, C. R. A., Williams, D. E. and Stoneham, A. M., Chem. Commun., 14, 12351236 (2000).Google Scholar
10.CASTEP 4.2 Academic Version, Licensed Under the UKCP-MSI Agreement, 1999. Rev Mod. Phys., 64, 1045 (1992)Google Scholar
11. Epling, W. S., Peden, C. H. F., Henderson, M. A. and Diebold, U., Surf. Sci., 412/413, 333 (1998).Google Scholar
12. Gercher, V. A. and Cox, D. F., Surf. Sci., 322, 177–1 (1995).Google Scholar