Surface Stress of Chloride Monolayer on Au(111) Electrode

Taking Cl-anion as an example, the statistical thermodynamic theory of surface stress of anion adsorption monolayer on Au(111) has been established by using the lattice gas model. The effective pair interaction energy, the surface stress and the two-dimensional isothermal compressibility in chloride adlayer on the Au(111) electrode surface have been calculated. The calculational result of the surface stress of chloride adlayer is associated with the experiment. At lower Cl-coverage, considering the contribution of ClO4-, the change of surface stress is approximately linearly correlated with charge density. For the Cl-/Au(111) system, the difference between surface stress and surface tension is the same order of magnitude of surface stress, which can′t be neglected. Therefore, Haisset al.′s experiment results have been successfully explained by the theory.