物理化学学报Issue(6)：1093-1104,12.DOI:10.3866/PKU.WHXB201504032
硫酸根离子对铁在弱碱性溶液中阳极溶解和钝化行为的影响
Effects of Sulfate Ions on Anodic Dissolution and Passivity of Iron in Slightly Alkaline Solutions
摘要
Abstract
The effects of sulfate concentration on the open circuit state and anodic polarization behavior of iron in dilute bicarbonate solutions were investigated using immersion tests, electrochemical measurements, and surface analysis techniques. In the absence of sulfate or in the presence of a low concentration of sulfate in dilute bicarbonate solutions, iron was in a passive state, with a corrosion potential of (-0.225±0.005) V. A high electrochemical impedance and low corrosion rate were obtained. No obvious active-passive transition was observed in the anodic polarization curves. In the presence of a high concentration of sulfate in dilute bicarbonate solutions, iron was in an active dissolution state, with a corrosion potential of (-0.790±0.010) V. A low electrochemical impedance, high corrosion rate, and typical active-passive transition in anodic polarization curves were observed and related to the sulfate concentration. In the presence of a high concentration of sulfate, the anodic polarization curves showed current peaks as a result of iron activation by sulfate ions. Sulfate ions of sufficiently high concentration in solutions degraded previously formed oxide layers on iron or transformed oxide layers in bicarbonate solutions. The transition of the open circuit state from passivity to active dissolution occurs at a lower sulfate concentration in a deaerated solution than in an aerated solution.关键词
铁/电化学行为/腐蚀失重/钝态/阳极溶解/X射线光电子能谱/电位-pH图Key words
Iron/Electrochemical behavior/Corrosion weightloss/Passivity/Anodic dissolution/X-ray photoelectron spectroscopy/Potential-pH diagram分类
化学化工引用本文复制引用
陈俊劼,肖茜,吕战鹏,AHSAN Ejaz,夏小峰,刘廷光..硫酸根离子对铁在弱碱性溶液中阳极溶解和钝化行为的影响[J].物理化学学报,2015,(6):1093-1104,12.基金项目
The project was supported by the International Cooperative Project Sponsored by Science and Technology Commission of Shanghai Municipality, China (13520721200), Specialized Research Fund for the Doctoral Program of Higher Education, China (20123108110021), and Shanghai Pujiang Project, China (12PJ1403600).上海市科委国际科技合作项目(13520721200),高等学校博士学科点专项科研基金博导类项目(20123108110021)及上海市浦江人才计划项目(12PJ1403600)资助 （13520721200）
