Interdiffusion coefficients were deduced (table 223) by means of Boltzmann-Matano analyses of the concentration profiles or by monitoring the thickness or resistance of diffusion cells as a function of time. It was found that the results which were obtained using the 3 methods agreed in the case of Ag0.5Cu0.5I solid solution. The interdiffusion coefficients were of the order of 10-7cm2/s for temperatures ranging from 570 to 620K. The general shapes of the concentration profiles indicated that Cu ion diffusivity made a greater contribution, in that the Cu concentration at the Ag-rich side was higher than the Ag concentration at the Cu-rich side. That is, more Cu than Ag diffused through the interfacial zone. This was in accord with a proposed co-ionic conductivity of the solid solution.

J.C.Bazán, R.S.Pettigrosso: Journal of Materials Science, 1996, 31[15], 4077-80

Table 223

Interdiffusion in AgI/CuI Couples