When hydrogen is dissolved in an oxide, protons and electrons make diffusion pair and thus lead to the transport of H_(2) under its chemical potential gradient. The present manuscript develops relationships between the chemical diffusion coefficient o...
When hydrogen is dissolved in an oxide, protons and electrons make diffusion pair and thus lead to the transport of H_(2) under its chemical potential gradient. The present manuscript develops relationships between the chemical diffusion coefficient of H_(2) and the diffusion coefficient of protons and electrons by determining thermodynamic factor of H_(2), W_(H)_(2).
When thermodynamic ideal behavior is assumed for protons and electrons, W_(H)_(2) turns out to be 4. If hydrogen solubility in the oxide follows Henrian ideal behavior, W_(H)_(2)= 1. In case hydrogen solubility obeys Sivert's law, we obtain W_(H)_(2)= 2.