Micro-electrochemical studies were made of H storage materials by using a micro-electrode technique. A C-fibre filament was placed in contact with single particles of the alloys, in 1M KOH solution, by using a micromanipulator. In this way, cyclic voltammetric, potential step experiments and in situ X-ray diffraction experiments could be carried out. The current responses were recorded as a function of time were analyzed by using a spherical diffusion model. The room-temperature diffusivity was 1.1 x 10-9 cm2/s.T.Nishina, H.Ura, I.Uchida: Journal of the Electrochemical Society, 1997, 144[4], 1273-8
Table 201
Diffusion of Co in Ni-Ge Alloys
Ge | Temperature (K) | D (cm2/s) |
0.008 | 1333 | 2.17 x 10-11 |
0.023 | 1333 | 2.59 x 10-11 |
0.034 | 1333 | 3.16 x 10-11 |
0.036 | 1333 | 3.67 x 10-11 |
0.048 | 1333 | 4.76 x 10-11 |
0.079 | 1333 | 8.18 x 10-11 |
0.008 | 1380 | 5.91 x 10-11 |
0.023 | 1380 | 7.61 x 10-11 |
0.042 | 1380 | 1.16 x 10-10 |
0.066 | 1389 | 1.43 x 10-10 |
0.079 | 1380 | 2.00 x 10-10 |
0.008 | 1418 | 1.20 x 10-10 |
0.023 | 1418 | 1.37 x 10-10 |
0.034 | 1418 | 1.51 x 10-10 |
0.048 | 1418 | 1.98 x 10-10 |
0.066 | 1418 | 2.41 x 10-10 |
0.080 | 1418 | 3.05 x 10-10 |
0.009 | 1471 | 2.34 x 10-10 |
0.023 | 1471 | 2.64 x 10-10 |
0.034 | 1471 | 2.76 x 10-10 |
0.048 | 1471 | 3.20 x 10-10 |
0.055 | 1471 | 3.60 x 10-10 |
0.077 | 1471 | 4.50 x 10-10 |