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Title: XAFS Studies of Silver Environments in Ion-Exchanged Glasses

Abstract

The X-ray absorption fine structure (XAFS) technique was used to analyze the structural geometry of Ag atoms introduced into soda-lime silicate glass and soda aluminosilicate glass by ion-exchange methods. The results show that Ag+ ions in aluminosilicate glass are coordinated by about two oxygens and the nearest-neighbor Ag-O distance increases when the Ag+-for-Na+ ion-exchange ratio is larger than 0.47. When the exchange ratio is low, the introduced Ag+ ions are stabilized at the non-bridge oxygen (NBO) site with a Ag-O distance of 2.20 A, and the Na+ ions in the AlO4 site are exchanged by Ag+ ions after full replacement of the NBO sites with a Ag-O distance of 2.28 A. The disorder of Ag-O coordination increases with increasing ion-exchange ratio in aluminosilicate glass where Ag+ ions are coordinated by NBO and bridge oxygen (BO)

Authors:
 [1];  [2]
  1. College of Materials Science and Engineering, Tongji University, Shanghai 200092 (China)
  2. Department of Physics, Martin Luther University of Halle, D-06108 Halle (Germany)
Publication Date:
OSTI Identifier:
21054654
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 882; Journal Issue: 1; Conference: XAFS13: 13. international conference on X-ray absorption fine structure, Stanford, CA (United States), 9-14 Jul 2006; Other Information: DOI: 10.1063/1.2644557; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION SPECTROSCOPY; ATOMS; CHEMICAL BONDS; FINE STRUCTURE; GLASS; INTERATOMIC DISTANCES; ION EXCHANGE; OXYGEN; SILICATES; SILVER; SILVER IONS; SODIUM CARBONATES; SODIUM IONS; X-RAY SPECTRA; X-RAY SPECTROSCOPY

Citation Formats

Yang, X. C., and Dubiel, M. XAFS Studies of Silver Environments in Ion-Exchanged Glasses. United States: N. p., 2007. Web. doi:10.1063/1.2644557.
Yang, X. C., & Dubiel, M. XAFS Studies of Silver Environments in Ion-Exchanged Glasses. United States. doi:10.1063/1.2644557.
Yang, X. C., and Dubiel, M. Fri . "XAFS Studies of Silver Environments in Ion-Exchanged Glasses". United States. doi:10.1063/1.2644557.
@article{osti_21054654,
title = {XAFS Studies of Silver Environments in Ion-Exchanged Glasses},
author = {Yang, X. C. and Dubiel, M.},
abstractNote = {The X-ray absorption fine structure (XAFS) technique was used to analyze the structural geometry of Ag atoms introduced into soda-lime silicate glass and soda aluminosilicate glass by ion-exchange methods. The results show that Ag+ ions in aluminosilicate glass are coordinated by about two oxygens and the nearest-neighbor Ag-O distance increases when the Ag+-for-Na+ ion-exchange ratio is larger than 0.47. When the exchange ratio is low, the introduced Ag+ ions are stabilized at the non-bridge oxygen (NBO) site with a Ag-O distance of 2.20 A, and the Na+ ions in the AlO4 site are exchanged by Ag+ ions after full replacement of the NBO sites with a Ag-O distance of 2.28 A. The disorder of Ag-O coordination increases with increasing ion-exchange ratio in aluminosilicate glass where Ag+ ions are coordinated by NBO and bridge oxygen (BO)},
doi = {10.1063/1.2644557},
journal = {AIP Conference Proceedings},
number = 1,
volume = 882,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
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