The properties of superionic glasses were studied, at temperatures ranging from 24 to 182C, by using complex impedance and radiation absorption methods. It was found that the Ag self-diffusivity ranged from 2 x 10-9 to 7 x 10-7cm2/s. It was noted that the properties depended upon the method of preparation and the thermal history of the samples. The conductivities and self-diffusion coefficients (table 229) were related by using the Nernst-Einstein equation. The Haven ratios, of between 0.19 and 0.38 (table 230), were suggested to indicate the operation of an interstitialcy mechanism for Ag transport.
K.Sebastian, G.H.Frischat: Physics and Chemistry of Glasses, 1992, 33[5], 199-203
Table 229
Self-Diffusion Parameters for Ag in AgI-Ag2O-B2O3 Glasses
AgI (mol%) | Ag2O (mol%) | B2O3 (mol%) | Do (cm2/s) | Q (kJ/mol) |
35.3 | 32.3 | 32.9 | 0.00082 | 32.1 |
39.8 | 29.9 | 30.8 | 0.00055 | 28.9 |
45.1 | 27.3 | 27.7 | 0.00055 | 26.8 |
50.1 | 25.2 | 25.3 | 0.00057 | 25.1 |
54.8 | 22.4 | 22.9 | 0.00036 | 22.2 |
Table 230
Haven Ratios for AgI-Ag2O-B2O3 Glasses
AgI (mol%) | Ag2O (mol%) | B2O3 (mol%) | Temperature (C) | H |
39.8 | 29.9 | 30.8 | 25 | 0.19 |
45.1 | 27.3 | 27.7 | 25 | 0.22 |
50.1 | 25.2 | 25.3 | 25 | 0.26 |
54.8 | 22.4 | 22.9 | 25 | 0.33 |
39.8 | 29.9 | 30.8 | 75 | 0.21 |
45.1 | 27.3 | 27.7 | 75 | 0.25 |
50.1 | 25.2 | 25.3 | 75 | 0.29 |
54.8 | 22.4 | 22.9 | 75 | 0.36 |
39.8 | 29.9 | 30.8 | 125 | 0.22 |
45.1 | 27.3 | 27.7 | 125 | 0.26 |
50.1 | 25.2 | 25.3 | 125 | 0.31 |
54.8 | 22.4 | 22.9 | 125 | 0.37 |
39.8 | 29.9 | 30.8 | 175 | 0.23 |
45.1 | 27.3 | 27.7 | 175 | 0.27 |