The 3D images taken with AFM of the TiO2 and 0.1% Ag–TiO2 thin films on stainless steel sheets are shown in Figure 6a and b, respectively. Data on surface morphology are summarized in Table 1. Overall, the range of grain size was narrower for 0.1% Ag–TiO2 in comparison to that of TiO2, while the apparent surface areas of all thin films are within the same ranges.