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Title: Titanium vacancy defects in sol-gel prepared anatase

Abstract

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.

Authors:
 [1];  [2]
  1. CSIRO Minerals, Bayview Avenue, Clayton, Vic., 3169 (Australia), E-mail: ian.grey@csiro.au
  2. CSIRO Minerals, Bayview Avenue, Clayton, Vic., 3169 (Australia)
Publication Date:
OSTI Identifier:
21015697
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal 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)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; DEFECTS; NANOSTRUCTURES; POWDERS; PROTONS; SIMULATION; SOL-GEL PROCESS; STOICHIOMETRY; TITANIUM OXIDES; VACANCIES; X-RAY DIFFRACTION

Citation Formats

Grey, Ian.E., and Wilson, Nicholas C. Titanium vacancy defects in sol-gel prepared anatase. United States: N. p., 2007. Web. doi:10.1016/j.jssc.2006.11.028.
Grey, Ian.E., & Wilson, Nicholas C. Titanium vacancy defects in sol-gel prepared anatase. United States. doi:10.1016/j.jssc.2006.11.028.
Grey, Ian.E., and Wilson, Nicholas C. Thu . "Titanium vacancy defects in sol-gel prepared anatase". United States. doi:10.1016/j.jssc.2006.11.028.
@article{osti_21015697,
title = {Titanium vacancy defects in sol-gel prepared anatase},
author = {Grey, Ian.E. and Wilson, Nicholas C.},
abstractNote = {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.},
doi = {10.1016/j.jssc.2006.11.028},
journal = {Journal of Solid State Chemistry},
number = 2,
volume = 180,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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