Effects of hydrogen adsorption on the surface-energy anisotropy of nickel

Using the interatomic potentials of the embedded atom method, the surface energies of six main low-index surfaces of nickel have been calculated numerically. The calculated data are well consistent with the results of other embedded atom methods. In the present work, we have investigated the evolution of the surface energy and its anisotropy of nickel when hydrogen atoms adsorbed. It was found that the surface having the lowest surface energy changed from (1 1 1) to (1 0 0) plane as hydrogen coverage increases, so that through surface energy minimization, nickel deposit should change its texture from 〈1 1 1〉 to 〈1 0 0〉 texture which keeps in agreement with experimental results. The accuracy of the dependence of the orientation on the surface energy may be assessed by examining the anisotropy ratio of surface energy. From this study we can conclude that the presence of adsorbed hydrogen can modify the surface energy anisotropy, and thus has important influences on nucleation, morphology and microstructure of nickel film.