摘要
用动电位法研究了铂氧化铁(Fe_3O_4,α-Fe_2O_3,γ-Fe_2O_3)电极在不同pH的H_3BO_3-Na_2B_4O_7水溶液中的阴极过程。对脱氧溶液中,较低过电位区域出现异常的Tafel常数,作者从电极过程动力学分析确认这-反应是氧化铁的固相还原反应。讨论了溶液pH对氧化铁还原反应速率的影响和氧化铁铁锈在腐蚀过程中的作用。
Cathodic processes of Ptj iron oxides(Fe_(3_ω)O_4,α-Fe_2O_3 or γ Fe_2O_3) electrodes in H_3BO_3-Na_2B_4O_7 solution with various pH's are studied by potentiodynamic method. It is found that cathodic processes would be interfered in the presence of oxygen. In deaerated solution, the three parallel successive cathodic processes are: solid phase reduction of iron oxide, solution phase reduction of iron oxide and hydrogen depolarization. However, in aerated solution, the process of solid phase reduction of iron oxide is displaced by the process of oxygen depolarization, and the latter may also overlap the process of solution phase reduction of iron oxide and blur it. Experiments have confirmed that the reduction rates of iron oxides are dependent on the pH of the solution. Decrease in pH causes increase in reduction rates. The effects of iron oxides on the corrosion processes of iron and steels are discussed.
出处
《中国腐蚀与防护学报》
CAS
CSCD
1990年第2期143-150,共8页
Journal of Chinese Society For Corrosion and Protection
基金
国家自然科学基金资助课题
