PEDOT:PSS Thin Film as Transparent Electrode in ITO-Free Organic Solar Cell

Two types of polar solvent materials namely glycerol and ethylene glycol (EG) were used in this study as dopants for PEDOT:PSS. The 2 to 10% of doped PEDOT:PSS were synthesized using sol-gel technique and were spin-coated onto glass substrate. The optical, conductivity and morphological characteristics of the doped PEDOT:PSS thin films were measured via UV-VIS spectrometer, two-point probes technique and AFM measurement, respectively. All films showed direct band gap behavior and compared to the pristine thin film, the doped PEDOT:PSS show higher transparency in visible range. Furthermore, the conductivity of glycerol and EG doped PEDOT:PSS thin films were also improved due to the changes in molecule alignment and interchain interaction in the thin films.