The diffusion of 18O in single crystals was measured at 1100 to 1500C in air (PO2 = 2 x 104Pa). The penetration profiles were measured by using secondary ion mass spectrometry, and the diffusion coefficients were deduced after allowing for evaporation of the sample and exchange of the diffusant with the ambient. The diffusion data (table 51) could be described by:
D (cm2/s) = 8.6 x 10-1 exp[-431(kJ/mol)/RT]
The activation energy for diffusion agreed with the activation energy obtained from deformation studies.
Diffusion of 18O in CoO in Air. J.L.Routbort, S.J.Rothman: Journal of Physics and Chemistry of Solids, 1986, 47[10], 993-8
Table 50
Diffusion of O in CoO Monocrystals
Temperature (C) | Method | PO2 (atm) | D (cm2/s) |
1150 | thin-layer | 2.1 x 10-1 | 1.7 x 10-14 |
1150 | thin-layer | 1 x 10-2 | 7.95 x 10-15 |
1150 | thin-layer | 2.5 x 10-3 | 5.90 x 10-15 |
1150 | thin-layer | 1 x 10-4 | 3.10 x 10-15 |
1150 | thin-layer | 2 x 10-6 | 5 x 10-15 |
1150 | thin-layer | 1 x 10-8 | 1.12 x 10-14 |
1200 | thin-layer | 2.1 x 10-1 | 5.37 x 10-14 |
1200 | implantation | 2.1 x 10-1 | 5.45 x 10-14 |
1200 | isotopic exchange | 2.1 x 10-1 | 5.35 x 10-14 |
1200 | thin-layer | 1 x 10-2 | 1.82 x 10-14 |
1200 | thin-layer | 2.5 x 10-3 | 1.17 x 10-14 |
1200 | thin-layer | 5 x 10-4 | 8.3 x 10-15 |
1200 | thin-layer | 1 x 10-4 | 6.75 x 10-15 |
1200 | isotopic exchange | 8.5 x 10-5 | 7.41 x 10-15 |
1200 | thin-layer | 4 x 10-5 | 8.91 x 10-15 |
1200 | thin-layer | 2 x 10-6 | 1.15 x 10-14 |
1200 | thin-layer | 1 x 10-7 | 1.82 x 10-14 |
1200 | thin-layer | 1 x 10-8 | 2.51 x 10-14 |
1250 | thin-layer | 1 x 10-8 | 4.73 x 10-14 |
continued
Table 50 (continued)
Diffusion of O in CoO Monocrystals
Temperature (C) | Method | PO2 (atm) | D (cm2/s) |
1300 | isotopic exchange | 2.1 x 10-1 | 3.85 x 10-13 |
1300 | thin-layer | 2.1 x 10-1 | 3.75 x 10-13 |
1300 | thin-layer | 1 x 10-2 | 1.73 x 10-13 |
1300 | thin-layer | 2.5 x 10-3 | 1.04 x 10-13 |
1300 | thin-layer | 5 x 10-4 | 9.33 x 10-14 |
1300 | thin-layer | 1 x 10-4 | 8.51 x 10-14 |
1300 | isotopic exchange | 8.5 x 10-5 | 8.49 x 10-14 |
1300 | thin-layer | 4 x 10-5 | 9.30 x 10-14 |
1300 | thin-layer | 2 x 10-6 | 1.05 x 10-13 |
1300 | thin-layer | 1 x 10-8 | 1.25 x 10-13 |
1400 | isotopic exchange | 2.1 x 10-1 | 5 x 10-12 |
1400 | thin-layer | 2.1 x 10-1 | 1.25 x 10-12 |
1400 | thin-layer | 1 x 10-2 | 7.94 x 10-13 |
1400 | thin-layer | 2.5 x 10-3 | 5.12 x 10-13 |
1400 | thin-layer | 5 x 10-4 | 4.30 x 10-13 |
1400 | thin-layer | 1 x 10-4 | 3.31 x 10-13 |
1400 | isotopic exchange | 8.5 x 10-5 | 3.38 x 10-13 |
1400 | thin-layer | 4 x 10-5 | 3.15 x 10-13 |
1400 | thin-layer | 2 x 10-6 | 3.2 x 10-13 |