氯离子吸附单层对Au(111)电极表面应力的贡献

以Cl-为例,应用格子气模型,建立了阴离子吸附层对Au(111)表面应力贡献的统计热力学理论,计算了吸附层Cl-离子间相互作用能、表面应力贡献和二维体积弹性模量.计算结果表明, Cl-吸附层对表面应力贡献的大小,与实验值相近;在Cl-低覆盖度时,经验包括ClO4-贡献,计算了表面应力变化-电荷密度曲线,近似呈线性关系;对于Cl-/Au(111)体系,表面应力与表面张力之差与表面应力同量级,两者差别不可忽略.较好地解释了有关的实验事实.

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.