fig1

Figure 1. (A) Current density transient during the anodization of Fe foil at 50 V in EG + 0.5 wt.% NH₄F + 3.0 wt.% water for 300 s at 60 °C. (B-G) FESEM images of anodic iron oxide films after 1, 5, 10, 30, 120 and 300 s, respectively. Insets show the corresponding cross-sectional image at each stage^[50]. Reproduced from Ref.^[50] with permission from Elsevier.