Solid-state dye-sensitized TiO2 solar cells using poly(3,4-ethylenedioxythiophene) as substitutes of iodine/iodide electrolytes and noble metal catalysts on FTO counter electrodes

Solid-state dye-sensitized TiO2 solar cells using commercially available ruthenium dye (Z907) as an hydrophobic sensitizing dye and poly(3,4-ethylenedioxythiophene) (PEDOT) as a hole conductor and a platinum-free counter electrodes were fabricated. The nanospace of the dyed TiO2 layer was filled with PEDOT through the in situ photoelectrochemical polymerization of bis-ethylenedioxythiophene (bis-EDOT). In this study, we revealed several factors for the photoelectrochemical polymerization and obtained the conversion efficiency of 2.6% with high open circuit voltage over 0.8 V.