Development of scanning electrochemical nano-scope and analyses of initiation mechanism and kinetics of localized interfacial reaction

应用微电化学新技术研究了实际材料与环境界面的非均相反应机理和动力学。虽然利用LIGA成功地研制了纳米探针电极，但由于探针对准困难，扫描电化学纳米示波器的研制未能完成。而将同轴双微电极应用于SECM探头，成功地提高了SECM图像的灵敏度和横向分辨率。应用SECM和amicro-electrochemical电池技术原位观察多晶铁表面在酸性硫酸盐介质中的腐蚀，发现铁的腐蚀是不均匀的，这取决于影响析氢反应性的晶体取向。铁钝化态的稳定性也强烈依赖于衬底取向。

New micro-electrochemical techniques developed were applied to investigate the mechanism and kinetics of heterogeneous reaction of the interface between practical materials and environment. Though a probe nano-electrode was successfully developed by using LIGA, the development of a scanning electrochemical nano-scope could not be completed because of the difficulty of probe alignment. However, the application of a coaxial double microelectrode to SECM probe was successfully attained the improvement of sensitivity and lateral resolution of SECM image. Application of this SECM and amicro-electrochemical cell technique to in situ observation of polycrystalline iron surface corroding in acidic sulphate media revealed that iron corroded heterogeneously depending on crystallographic orientation which affected the hydrogen evolution reactivity. The stability of passive state on iron was also strongly dependent on the substrate orientation.