Figure 2

UV-vis spectra of PTHA-coated TiO ₂ electrodes. (a, b, c) PTHA prepared by surface-bound polymerization with various oxidizing conditions: dipping in FeCl₃ (a) at room temperature for 24 h, (b) at 80°C for 10 h and (c) at 80°C for 24 h. (d) PTHA prepared via direct polymer adsorption by dipping TiO₂ electrodes in PTHA solution at 80°C for 24 h. (Inset) Photograph of PTHA-coated TiO₂ electrodes.