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Title: Dependence of the mixed alkali effect on temperature and total alkali oxide content in y[xLi{sub 2}O.(1-x)Na{sub 2}O].(1-y)B{sub 2}O{sub 3} glasses

Abstract

The complex conductivity spectra of mixed alkali borate glasses of compositions y [xLi{sub 2}O.(1-x)Na{sub 2}O].(1-y)B{sub 2}O{sub 3} (with x=0.0, 0.2, 0.4, 0.6, 0.8, 1.0; y=0.1, 0.2, 0.3) in a frequency range between 10{sup -2}Hz and 3MHz and at temperatures ranging from 298 to 573K have been studied. For each glass composition the conductivities show a transition from the dc values into a dispersive regime where the conductivity is found to increase continuously with frequency, tending towards a linear frequency dependence at sufficiently low temperatures. Mixed alkali effects (MAEs) in the dc conductivity and activation energy are identified and discussed. It has been for the first time found that the strength of the MAE in the logarithm of the dc conductivity linearly increases with the total alkali oxide content, y, and the reciprocal temperature, 1/T.

Authors:
 [1]
  1. Institut fuer Physikalische Chemie and Sonderforschungsbereich 458, Westfaelische Wilhelms-Universitaet Muenster, Corrensstrasse 30, 48149 Muenster (Germany). E-mail: yonggao@uni-muenster.de
Publication Date:
OSTI Identifier:
20784772
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 178; Journal Issue: 11; Other Information: DOI: 10.1016/j.jssc.2005.08.027; PII: S0022-4596(05)00380-4; Copyright (c) 2005 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; BORATES; BORON OXIDES; ELECTRIC CONDUCTIVITY; GLASS; LITHIUM OXIDES; SODIUM OXIDES; SPECTRA; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K

Citation Formats

Gao Yong. Dependence of the mixed alkali effect on temperature and total alkali oxide content in y[xLi{sub 2}O.(1-x)Na{sub 2}O].(1-y)B{sub 2}O{sub 3} glasses. United States: N. p., 2005. Web.
Gao Yong. Dependence of the mixed alkali effect on temperature and total alkali oxide content in y[xLi{sub 2}O.(1-x)Na{sub 2}O].(1-y)B{sub 2}O{sub 3} glasses. United States.
Gao Yong. Tue . "Dependence of the mixed alkali effect on temperature and total alkali oxide content in y[xLi{sub 2}O.(1-x)Na{sub 2}O].(1-y)B{sub 2}O{sub 3} glasses". United States. doi:.
@article{osti_20784772,
title = {Dependence of the mixed alkali effect on temperature and total alkali oxide content in y[xLi{sub 2}O.(1-x)Na{sub 2}O].(1-y)B{sub 2}O{sub 3} glasses},
author = {Gao Yong},
abstractNote = {The complex conductivity spectra of mixed alkali borate glasses of compositions y [xLi{sub 2}O.(1-x)Na{sub 2}O].(1-y)B{sub 2}O{sub 3} (with x=0.0, 0.2, 0.4, 0.6, 0.8, 1.0; y=0.1, 0.2, 0.3) in a frequency range between 10{sup -2}Hz and 3MHz and at temperatures ranging from 298 to 573K have been studied. For each glass composition the conductivities show a transition from the dc values into a dispersive regime where the conductivity is found to increase continuously with frequency, tending towards a linear frequency dependence at sufficiently low temperatures. Mixed alkali effects (MAEs) in the dc conductivity and activation energy are identified and discussed. It has been for the first time found that the strength of the MAE in the logarithm of the dc conductivity linearly increases with the total alkali oxide content, y, and the reciprocal temperature, 1/T.},
doi = {},
journal = {Journal of Solid State Chemistry},
number = 11,
volume = 178,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
  • Graphical abstract: Composition dependence of density and Urbach energy of Co{sup 2+} and Ni{sup 2+} doped ZLKB glasses: (a) Co{sup 2+} doped glasses and (b) Ni{sup 2+} doped glasses. Both are exhibited mixed alkali effect. Highlights: ► Mixed alkali effect is observed. ► Band gap studies indicate that the glasses are structural stable. ► The glasses are observed to be partially covalent in nature. -- Abstract: Co{sup 2+} and Ni{sup 2+} ions doped 20ZnO + xLi{sub 2}O + (30 − x) K{sub 2}O + 50B{sub 2}O{sub 3} (5 ≤ x ≤ 25) mol% glasses are prepared using melt quenching technique.more » Structural changes of the prepared glasses by addition of transition metal oxides, CoO and NiO are investigated by UV–vis–NIR, FT-IR spectroscopy and XRD. The XRD pattern indicates the amorphous nature of prepared glasses. FT-IR measurements of the all glasses revealed that the network structure of the glasses are mainly based on BO{sub 3} and BO{sub 4} units placed in different structural groups in which the BO{sub 3} units being dominant. The optical absorption spectra suggest the site symmetry of Co{sup 2+} and Ni{sup 2+} ions in the glasses are near octahedral. Crystal field and inter-electronic repulsion parameters are also evaluated. The optical band gap and Urbach energies exhibited the mixed alkali effect. Various physical parameters such as density, refractive index, optical dielectric constant, polaron radius, electronic polarizability and inter-ionic distance are also determined.« less
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