Structure of the Hydrated α-Al2O3(0001) Surface
10.1126/science.288.5468.1029
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

The physical and chemical properties of the hydrated α-Al2O3(0001) surface are important for understanding the reactivity of natural and synthetic aluminum-containing oxides. The structure of this surface was determined in the presence of water vapor at 300 kelvin by crystal truncation rod diffraction at a third-generation synchrotron x-ray source. The fully hydrated surface is oxygen terminated, with a 53% contracted double Al layer directly below. The structure is an intermediate between α-Al2O3and γ-Al(OH)3, a fully hydroxylated form of alumina. A semiordered oxygen layer about 2.3 angstroms above the terminal oxygen layer is interpreted as adsorbed water. The clean α-Al2O3(0001) surface, in contrast, is Al terminated and significantly relaxed relative to the bulk structure. These differences explain the different reactivities of the clean and hydroxylated surfaces.

Bibliography

Eng, P. J., Trainor, T. P., Brown Jr., G. E., Waychunas, G. A., Newville, M., Sutton, S. R., & Rivers, M. L. (2000). Structure of the Hydrated α-Al2O3(0001) Surface. Science, 288(5468), 1029–1033.

Authors 7
  1. Peter J. Eng (first)
  2. Thomas P. Trainor (additional)
  3. Gordon E. Brown Jr. (additional)
  4. Glenn A. Waychunas (additional)
  5. Matthew Newville (additional)
  6. Stephen R. Sutton (additional)
  7. Mark L. Rivers (additional)
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  52. Supported by Department of Energy (DOE) grant DE-FG03-93ER14347-A007 (Stanford University) DOE grant DE-FGO2-94ER14466 National Science Foundation grant EAR-9906456 and the W. M. Keck foundation (GeoSoilEnviroCARS University of Chicago). Use of the Advanced Photon Source was supported by the DOE Basic Energy Sciences Office of Energy Research under contract W-31-109-ENG-38. We thank J. Fitts D. Grolimund F. Sopron and N. Lazarz for their assistance with the measurements and J. V. Smith for constructive comments on the manuscript.
Dates
Type When
Created 23 years ago (July 27, 2002, 5:48 a.m.)
Deposited 8 months, 2 weeks ago (Dec. 8, 2024, 2:04 p.m.)
Indexed 4 days, 20 hours ago (Aug. 21, 2025, 12:47 p.m.)
Issued 25 years, 3 months ago (May 12, 2000)
Published 25 years, 3 months ago (May 12, 2000)
Published Print 25 years, 3 months ago (May 12, 2000)
Funders 0

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@article{Eng_2000, title={Structure of the Hydrated α-Al2O3(0001) Surface}, volume={288}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.288.5468.1029}, DOI={10.1126/science.288.5468.1029}, number={5468}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Eng, Peter J. and Trainor, Thomas P. and Brown Jr., Gordon E. and Waychunas, Glenn A. and Newville, Matthew and Sutton, Stephen R. and Rivers, Mark L.}, year={2000}, month=may, pages={1029–1033} }