513680.fig.002a
(a)
513680.fig.002b
(b)
Figure 2: Physical characterization of different-sized nanotube surfaces. (a) SEM micrographs of self-aligned TiO2 nanotubes with different diameters. The images show highly ordered nanotubes with four different pore sizes between 30–100 nm. (b) Table with average roughness ( ) and surface contact angle measurements for Ti and 30–100 nm TiO2 nanotube surfaces.