Evaluation and Optimization to Recycle Used TiO₂ Photoelectrode for Dye-Sensitized Solar Cells

Figure 4

FESEM images of ((a), (c)) bare TiO₂ film and TiO₂ film after use of (b) 5 × 10⁻³ M and (d) 5 M NaOH solutions as desorption agents.

(a)

(b)

(c)

(d)