engleski

Dielectric features of Au2O3 doped Li2O-SiO2 glass system-influence of Pb3O4

Studies on dielectric properties viz., ε′ (dielectric permittivity), M, Z and σac as functions of frequency and temperature (over wide ranges), of glasses/glass-ceramics give quantitative information on their insulating character. Such studies are also useful for understanding structural aspects of these glasses to a great extent. In this work Pb3O4 mixed Li2O-SiO2:Au2O3 glasses were synthesized and heat-treated. Analysis of the results of various characterization techniques indicated increased degree of internal augmentation between various structural groups of the glass network. Observed decrease of ε′ with Au2O3 content up to 0.04 mol% was attributed to the decreased magnitude of space charge polarization due to growing presence of PbO4 units in the glass network. Dipolar relaxation effects of these samples were evaluated using Cole-Cole plots. Variation of conductivity with Au2O3 concentration was analyzed using polaronic tunneling model. Conclusions of these results were found to be in in concurrence with spectroscopic studies. Overall, the presence of Pb3O4 caused reduction the conductivity of these glasses.

Pb3O4; Au ions; Li2O-SiO2 glasses; Dielectric studies; A.C. conductivity

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