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

Figure 4

Current density versus time curves recorded during anodization of low-purity Sn in the A-type (a) and B-type cells (b) at various anodizing potentials together with the dependence between an average steady-state current density and anodizing potential (c).

(a)

(b)

(c)