Formation of Nanoporous Tin Oxide Layers on Different Substrates during Anodic Oxidation in Oxalic Acid Electrolyte

Figure 8

FE-SEM images of Sn wire before (a) and after 30 min of anodization in 0.3 M at 5 V (b–f). Top (a, b), bottom (c), and cross-sectional (e, f) views of the anodic oxide layer.

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(b)

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