Poly(3,3-dibenzyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine)/Platinum Composite Films as Potential Counter Electrodes for Dye-Sensitized Solar Cells

In this study, poly(3,3-dibenzyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine)/platinum composite films (PProDOT-Bz2/Pt) were used as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs). The composite films were prepared on fluorine-doped tin oxide (FTO) glass by radio frequency (RF) sputtering to deposit platinum (Pt) for 30 s. Afterwards, PProDOT-Bz2 was deposited on the Pt–FTO glass via electrochemical polymerization. The electron transfer process of DSSCs was investigated using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The DSSCs with 0.05 C/cm2 PProDOT-Bz2-Pt composite films showed an open circuit voltage (Voc) of 0.70 V, a short-circuit current density (Jsc) of 7.27 mA/cm2, and a fill factor (F.F.) of 68.74%. This corresponded to a photovoltaic conversion efficiency (η) of 3.50% under a light intensity of 100 mW/cm2