Oxidation of Fe Whiskers and Surface Diffusion Observed by Environmental TEM

Metal oxidation is one of the spontaneous chemical reaction, which is hard to control. Most metals inevitably have at least a few layers of oxides on the surface in natural environment. Because of the large impact of metal oxidation on infrastructure and transportation, surface oxidation and its role on structure and property have attracted significant attentions on the fundamental aspects of oxygen diffusion into the metal or metal ion transport [1, 3]. Furthermore, iron/iron oxide is an attractive material for application, such as photo catalysis and electrode for lithium batteries [2], so the study of oxidation Fe material is also interesting for nanotechnology [3]. However understanding Fe oxidation in small length scale so far has been limited, since it is hard to observe ionic transport directly due to the spatial and temporal resolution limit.