823254.fig.004a
(a) DMF 0%
823254.fig.004b
(b) DMF 5%
823254.fig.004c
(c) DMF 10%
823254.fig.004d
(d) DMF 15%
Figure 4: SEM images of surface morphology of composite SiO2-TiO2 films without DMF and with DMF ratios from 5% to 15%.