弱碱性介质中氯离子对铜电极腐蚀行为的影响

应用循环伏安法、X射线光电子能谱法、电化学阻抗谱法以及现场椭圆偏光法研究了在弱碱性介质中添加Cl－对铜电极腐蚀行为的影响.结果表明， Cl－的加入能加剧铜电极的腐蚀，使腐蚀电流以及现场椭圆偏振参数Δ的变化范围都增大1个数量级， Cl－对Cu2O的掺杂将使铜电极的表面膜变得疏松，膜的耐蚀性变差.椭圆偏光实验不仅与电化学和能谱实验的结果一致，而且还能定性地、清楚地分辨出铜电极腐蚀过程中Cu2O的生成、Cl－对Cu2O的掺杂、CuO的生成等不同阶段；同时，利用恰当的模型还能定量地确定各个阶段铜电极表面膜的组成、厚度的变化，从而为研究铜电极的腐蚀与防护机理提供更多有用信息.

Effect of Cl-on the Corrosion Behavior of Copper Electrode in Weak-alkaline Medium

The effect of C1- on the corrosion behavior of copper electrode in weak-alkaline medium was studied by cyclic voltammetry, X-ray photoelectron spectroscopy (XPS), in-situ ellipsometry and electrochemical impedance spectroscopy (EIS) . The results showed that Cl- had remarkable influence on the corrosion behavior of copper. The corrosion current of copper electrode in solution with Cl- was about 10 times larger than that without Cl-. It was due to the decrease of the corrosion resistance of the film because the film was doped by Cl- ion. The ellipsometry results not only were in good agreement with the electrochemical and XPS measurements qualitatively, but also could be used to distinguish every stage of corrosion, such as the formation of Cu2O film, the Cu2O film doped by Cl- ion, the formation of CuO, and so on. Moreover, based on reasonable models as well as optical results, the composition, thickness and refractive index of the surface film on the electrode could be calculated quantitatively, which would provide important evidences for the reaction mechanism studies.