Electrical Properties of Cr₂O₃-Fe₂O₃-P₂O₅ Glasses II

Abstract

The electrical properties of xCr2O3-(40-x)Fe2O3-60P2O5, 0 ≤ x ≤ 10, (mol%) glasses have been investigated by impedance spectroscopy. In the glasses containing up to ~ 5 mol% Cr2O3, electrical conductivity increases due to the increase in the Fe2+/Fetot ratio. The conduction in these glasses is independent on Cr2O3 and it is controlled by the polaron hopping between iron ions. The electrical conductivity of the partially crystallized sample with 10 mol% Cr2O3 slightly increases although the Fe2O3 content and the fraction of Fe2+ ions are smaller. This effect is related to the formation of highly disruptive regions around the β-CrPO4 and Fe3(P2O7)2 crystallites in the glass matrix of this sample. These interconnected disruptive regions form the easy conductive pathways leading to a higher conductivity. Changes in the dielectric permittivity in chromium iron phosphate glasses are dependent on the Fe2+/Fetot ratio and, therefore, associated with the concentration of polarons related to Fe2+ and Fe3+ sites.

Department(s)

Nuclear Engineering and Radiation Science

Second Department

Materials Science and Engineering

Keywords and Phrases

Phosphate Glasses; Electical Conductivity

International Standard Serial Number (ISSN)

0022-3093

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2010 Elsevier, All rights reserved.

Publication Date

01 Nov 2010

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