| Author(s): |
Ferreira Nascimento, Marcio Luis
[1]
;
Martins Rodrigues, Ana Candida
[2]
;
Souquet, Jean Louis
[2, 3]
Total Authors: 3
|
| Affiliation: | [1] Univ Fed Bahia, Inst Humanities Arts & Sci, Vitreous Mat Lab, BR-40170115 Salvador, BA - Brazil
[2] Univ Fed Sao Carlos, Dept Mat Engn, Lab Mat Vitreos, BR-13565905 Sao Carlos, SP - Brazil
[3] ENSEEG, Lab Electrochim & Physicochim Mat & Interfaces, F-38402 St Martin Dheres - France
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | PHYSICS AND CHEMISTRY OF GLASSES-EUROPEAN JOURNAL OF GLASS SCIENCE AND TECHNOLOGY PART B; v. 51, n. 1, p. 69-77, FEB 2010. |
| Web of Science Citations: | 6 |
| Abstract | |
Experimental data from the literature on electrical conductivity are reviewed for 43 glass compositions in the xLi(2)O-(1-x)SiO(2) system (0.05<x<0.67). The data are presented herein as a function of temperature and in isothermal plots as a function of the Li(2)O molar ratio, x. Below the glass transition temperature, T(g), the experimental ionic conductivity of all the compositions follows an Arrhenius law, sigma=sigma(0)exp(-E(A)/RT). The large quantity of experimental data minimizes the experimental inaccuracy in glass composition and conductivity measurements, thus allowing for accurate estimates of the mean values of the pre-exponential term (sigma(0)) of the Arrhenius expression and the activation energy (E(A)), as well as a precise assessment of the variations in isothermal conductivity with the molar ratio, x. The value of the pre-exponential term and the variation of isothermal conductivity and activation energy with x are then interpreted by reference to general concepts for ionic transport in solids, and to the so-called weak electrolyte theory. The Anderson \& Stuart model is employed to estimate the absolute values of activation energy. The association of the intrinsic cationic pair model and the weak electrolyte theory provides a good description of the variations in electrical conductivity and activation energy as a function of the Li(2)O molar ratio. The Anderson \& Stuart model leads to consistent absolute values of activation energy only if an arbitrarily chosen value of jump distance is employed in the corresponding expression. (AU) | |
| FAPESP's process: | 07/08179-9 - Kinetic processes in glasses and glass ceramics |
| Grantee: | Edgar Dutra Zanotto |
| Support Opportunities: | Research Projects - Thematic Grants |