Titanium vacancy defects in sol-gel prepared anatase
- CSIRO Minerals, Bayview Avenue, Clayton, Vic., 3169 (Australia)
Rietveld refinement of powder X-ray diffraction data for nanocrystalline anatase samples prepared by different sol-gel methods shows that the samples contain high concentrations ({<=} 20%) of titanium vacancies, the levels of which decrease with increasing crystallite size. Debye function modelling of anatase clusters with different well-defined sizes, shapes and stoichiometries confirmed that the titanium vacancy concentrations obtained from the Rietveld refinements are correct. However, the Debye modelling showed that for nanocrystals smaller than {approx}4 nm, the Rietveld modelling gives artificially high cell parameters. Density function theory calculations show that the titanium vacancies are stable defects when the vacancy sites are charge-balanced by incorporation of protons. - Graphical abstract: Relaxed structure from DFT modelling of anatase containing one titanium vacancy and four protons.
- OSTI ID:
- 21015697
- Journal Information:
- Journal of Solid State Chemistry, Vol. 180, Issue 2; Other Information: DOI: 10.1016/j.jssc.2006.11.028; PII: S0022-4596(06)00627-X; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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