摘要
重点研究了纯铁(Fe)在2∶1酸性AlCl_3-氯化1-甲基-3-乙基咪唑(AlCl_3-EMIC)中的阳极行为。通过三电极体系测定了Fe在AlCl_3-EMIC中的阳极极化和不同电位下的电流-时间曲线,利用恒电位溶解计算了Fe溶解的价态,最后通过扫描电子显微镜(SEM)观察了不同电流密度下Fe的溶解形貌。结果表明:Fe表面的氧化膜会阻碍Fe的溶解,在去除氧化膜后,当电位达到-0.35V时,Fe开始发生活性溶解,产物为Fe(Ⅱ)。Fe的阳极电流密度随电位的增加而增加,达到峰值后显著下降。小电流密度下(如2mA·cm^(-2)),Fe的溶解形貌随时间的延长,呈现先点状腐蚀再均匀腐蚀的特点;而大电流密度下(如15mA·cm^(-2)),Fe电极表面会生成一层固态物质,同时可见清晰的划痕,即不发生明显的腐蚀。
The anodic behavior of Fe in 2∶1acidic AlCl_3-1-ethyl-3-methyl-imidazolium chloride(AlCl_3-EMIC)ionic liquid was investigated in this paper.Anodic polarization and chronoamperometry was measured using three-electrode system.The valence state of dissolved Fe was calculated by potentiostatic process.The surface morphologies of Fe were characterized using a scanning electron microscopy(SEM).The results showed that the oxide film would restrain the dissolution of Fe.After the oxide film was removed,Fe began to dissolve at the potential of-0.35 Vversus Pt.The anodic current density increased rapidly to a maximum with the positive shift of potential and than decreased abruptly.The product existed in the form of Fe(Ⅱ).After galvanostatic process at 2 mA·cm^(-2),the surface of Fe showed a pitting morphology,which became homogeneous as time prolonged.With a larger anodic current applied(15mA·cm^(-2)),no obvious corrosion occurred on the surface of Fe electrode with precipitate formed.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2016年第S1期341-346,共6页
CIESC Journal
基金
国家自然科学基金面上项目(51271166)~~
