The self-diffusion of Na+ and Cs+ ions in the hydrous oxide was studied at temperatures of 25, 42, 50 and 57C. The conditions were designed to favor only a particle diffusion mechanism, and the self-diffusion coefficients (table 134) were determined by using the Paterson approximation. The activation energies, entropies and free energies of activation were calculated, and a tentative model for alkali ion transport in this oxide was developed.
K.Benyamin: Solid State Ionics, 1994, 73[3-4], 303-8
Table 134
Diffusivity of Cs and Na in TiO2
Temperature (C) | Ion | D (m2/s) |
25 | Na+ | 7.00 x 10-13 |
25 | Cs+ | 9.60 x 10-13 |
42 | Na+ | 9.60 x 10-13 |
42 | Cs+ | 1.26 x 10-12 |
50 | Na+ | 1.25 x 10-12 |
50 | Cs+ | 1.64 x 10-12 |
57 | Na+ | 1.81 x 10-12 |
57 | Cs+ | 2.57 x 10-12 |