Characterization and Photocatalytic Activity of TiO₂ Nanotube Films Prepared by Anodization

Figure 3

Front view of SEM images of TNT synthesized at different anodization voltages: (a) 10 V, (b) 20 V, (c) 30 V, and (d) 40 V.

(a)  

(b)

(c)

(d)