The surface diffusion coefficients of Pt adatoms were measured  in situ  on polycrystalline Pt electrodes which were immersed in 1M HClO4, 1M H3PO4 or 0.5M H2SO4 electrolytic solutions, under various potentials. The observed changes in the surface diffusivities, as well as the rate of change of the diffusivity with potential, confirmed the adsorbate-induced relaxation of Pt electrode surfaces.

M.Hidalgo, M.L.Marcos, J.G.Velasco: Applied Physics Letters, 1995, 67[10], 1486-8