磁场作用下铁／硫酸体系阳极过程全息显微研究

利用电化学和一息显微摄影技术研究弱磁场（Ｂ≤２００ｍＴ）作用下，０．５ｍｏｌ·ｄｍ＾－３Ｈ２ＳＯ４溶液中铁的阳极溶解、恒电位电流振荡以及钝化铁再活化等过程，并从电极／溶液界面现场显微动态观察的角度探讨了磁场对上述过程的影响。磁场的存在主要通过增加液相传质速度影响电化学过程。外加磁场对铁的活化溶解没有明显的影响，但加快了预钝化区铁的溶解，从而显著改变铁的电化学振荡行为；钝化铁再活化过程主要取决于电极电位,与外加磁场没有关系;研究表明全息显微术是磁电化学研究中一种十分有效的方法.

HOLOGRAPHIC MICROPHOTOGRAPHY STUDY OF THE ANODIC PROCESS OF IRON IN SULFURIC ACID SOLUTION IN A MAGNETIC FIELD

Electrochemical methods and holographic microphotography were used to investigate the anodic dissolution and potentiostatic current oscillations of iron, and reactivation of passivated iron in 0.5 moldm-3 H2SO4 solution in a weak magnetic field (B200 mT). The results showed that magnetic field affected the electrochemical process chiefly by accelerating the mass transport. The external magnetic field had no obvious effect on the active dissolution of iron. However, it did speed up the dissolution in the prepassive range, changing oscillation behaviors of iron in 0.5 moldm-3 H2SO4. The reactivation process of passivated iron was mainly determined by the electrode potential, and had little to do with the external magnetic field. The investigation also proves that holographic microphotography is a very effective technique in the study of effects of the magnetic field on the electrochemical processes.