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 (less-than-or-equals, slant 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 ~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.
Description
ScienceDirect - Journal of Solid State Chemistry : Titanium vacancy defects in sol–gel prepared anatase
%0 Journal Article
%1 Grey2007
%A Grey, Ian.E.
%A Wilson, Nicholas C.
%D 2007
%J Journal of Solid State Chemistry
%K TiO2 anatase lattice_expansion
%N 2
%P 670 - 678
%R 10.1016/j.jssc.2006.11.028
%T Titanium vacancy defects in sol-gel prepared anatase
%U http://www.sciencedirect.com/science/article/B6WM2-4MG5WDH-3/2/7fb498316342677cae25c5d01ef20190
%V 180
%X 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 (less-than-or-equals, slant 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 ~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.
@article{Grey2007,
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 ([less-than-or-equals, slant] 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 ~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.},
added-at = {2010-08-27T11:24:07.000+0200},
author = {Grey, Ian.E. and Wilson, Nicholas C.},
biburl = {https://www.bibsonomy.org/bibtex/23e46d412dc5ae09d15e6a6bf5f9c7b25/pmd},
description = {ScienceDirect - Journal of Solid State Chemistry : Titanium vacancy defects in sol–gel prepared anatase},
doi = {10.1016/j.jssc.2006.11.028},
groups = {public},
interhash = {6057bd4feb6bf907763de7e8bb470292},
intrahash = {3e46d412dc5ae09d15e6a6bf5f9c7b25},
issn = {0022-4596},
journal = {Journal of Solid State Chemistry},
keywords = {TiO2 anatase lattice_expansion},
number = 2,
pages = {670 - 678},
timestamp = {2011-09-27T11:21:47.000+0200},
title = {Titanium vacancy defects in sol-gel prepared anatase},
url = {http://www.sciencedirect.com/science/article/B6WM2-4MG5WDH-3/2/7fb498316342677cae25c5d01ef20190},
username = {pmd},
volume = 180,
year = 2007
}