ffects of electrochemical reaction and self - stress on hydrogen diffusion in tubular membranes during galvanostatic charging *
نویسنده
چکیده
Based on theories of hydrogen electrode reactions at the palladium surface and self-stresses of hydrogen in thin tubular shells established earlier, we numerically calculate transport properties of hydrogen across a tubular membrane under galvanostatic charging conditions. It is found that the exited hydrogen flux is much less than the charging current since the hydrogen combination reaction takes place at the outer surface. On the other hand, the overall system is in an unstable state after a long time charging; this makes the determination of hydrogen diffusivity difficult in experiments. The theoretical results are in good agreement with experimental data obtained before. 2003 Elsevier B.V. All rights reserved.
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