A novel kinetic Monte Carlo simulator was developed to investigate H diffusion in metals and alloys. The results of the H diffusion coefficients in Pd, Ag and Pd1−xAgx (x ≤ 0.5) were in excellent agreement with experimental results. Two different diffusion sites, Pd-rich diffusion site and Ag-rich diffusion site, were found to be necessary to explain the diffusion behaviors of H in Pd-Ag alloys. Detailed analysis clarified that H atoms preferentially diffused through the Pd-rich region of Pd–Ag alloys at low Ag concentrations, and that the H diffusion process at low Ag contents was dominated by the jumps in Pd-rich regions. The migration barrier of H from Pd-rich diffusion site to Ag-rich diffusion site was estimated to be between 0.40 and 0.45eV.

Development of New Kinetic Monte Carlo Simulator for Hydrogen Diffusion Process in Palladium–Silver Alloys. H.Kurokawa, K.Bada, M.Koyama, M.Kubo, A.Miyamoto: Applied Surface Science, 2005, 244[1-4], 636-9