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Title: Anatase-TiO2 Nanomaterials: Analysis of Key Parameters Controlling Crystallization

Abstract

Nanoparticulated TiO2 materials with anatase structure were synthesized by using a microemulsion method. The structural characteristics of the amorphous solid precursors and their evolution during thermal treatments were studied by using X-ray absorption structure (X-ray absorption near edge structure XANES and extended X-ray absorption fine structure EXAFS), XRD-PDF (X-ray diffraction-pair distribution function), and infrared spectroscopy. Concerning the precursor materials, XANES and EXAFS showed a local order closely related to that of the anatase structure but containing defective, undercoordinated Ti5c4+ species in addition to normal Ti6c4+ species. The PDF technique detects differences among samples in the local order (below 1 nm) and showed that primary particle size varies throughout the amorphous precursor series. The physical interpretation of results concerning the amorphous materials and their evolution under thermal treatment gives conclusive evidence that local, intraparticle ordering variations determine the temperature for the onset of the nucleation process and drive the solid behavior through the whole crystallization process. The significance of this result in the context of current crystallization theories of oxide-based nanocrystalline solids is discussed.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
959769
Report Number(s):
BNL-82755-2009-JA
Journal ID: ISSN 0002-7863; JACSAT; TRN: US201016%%913
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the American Chemical Society; Journal Volume: 129
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; ABSORPTION; CRYSTALLIZATION; DISTRIBUTION; FINE STRUCTURE; MICROEMULSIONS; NUCLEATION; PARTICLE SIZE; PRECURSOR; SPECTROSCOPY; MATERIALS; national synchrotron light source

Citation Formats

Fernandez-Garcia,M., Belver, C., Hanson, J., Wang, X., and Rodriguez, J. Anatase-TiO2 Nanomaterials: Analysis of Key Parameters Controlling Crystallization. United States: N. p., 2007. Web. doi:10.1021/ja074064m.
Fernandez-Garcia,M., Belver, C., Hanson, J., Wang, X., & Rodriguez, J. Anatase-TiO2 Nanomaterials: Analysis of Key Parameters Controlling Crystallization. United States. doi:10.1021/ja074064m.
Fernandez-Garcia,M., Belver, C., Hanson, J., Wang, X., and Rodriguez, J. Mon . "Anatase-TiO2 Nanomaterials: Analysis of Key Parameters Controlling Crystallization". United States. doi:10.1021/ja074064m.
@article{osti_959769,
title = {Anatase-TiO2 Nanomaterials: Analysis of Key Parameters Controlling Crystallization},
author = {Fernandez-Garcia,M. and Belver, C. and Hanson, J. and Wang, X. and Rodriguez, J.},
abstractNote = {Nanoparticulated TiO2 materials with anatase structure were synthesized by using a microemulsion method. The structural characteristics of the amorphous solid precursors and their evolution during thermal treatments were studied by using X-ray absorption structure (X-ray absorption near edge structure XANES and extended X-ray absorption fine structure EXAFS), XRD-PDF (X-ray diffraction-pair distribution function), and infrared spectroscopy. Concerning the precursor materials, XANES and EXAFS showed a local order closely related to that of the anatase structure but containing defective, undercoordinated Ti5c4+ species in addition to normal Ti6c4+ species. The PDF technique detects differences among samples in the local order (below 1 nm) and showed that primary particle size varies throughout the amorphous precursor series. The physical interpretation of results concerning the amorphous materials and their evolution under thermal treatment gives conclusive evidence that local, intraparticle ordering variations determine the temperature for the onset of the nucleation process and drive the solid behavior through the whole crystallization process. The significance of this result in the context of current crystallization theories of oxide-based nanocrystalline solids is discussed.},
doi = {10.1021/ja074064m},
journal = {Journal of the American Chemical Society},
number = ,
volume = 129,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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