Polymer solar cells with inkjet-printed doped-PEDOT: PSS anode

In this article, we describe the development of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)-based ink for the fabrication of indium tin oxide (ITO)-free polymer solar cells (PSCs). The ink consisted of PEDOT:PSS, suitably doped with dimethyl sulfoxide (DMSO) in solution. The printed PEDOT:PSS showed electrical conductivity of 1000 S/cm and transparency around 85% in the visible range. Then, they were employed as anodes in ITO-free polymer PSCs based on a bulk heterojunction of poly(3-hexylthiophene) and [6,6]-phenyl C-61-butyric acid methyl ester. The effects of surface treatments (O-2 plasma, UV ozone) of glass substrates on the quality and morphology of the printed layer were investigated in order to improve the anode quality. The performances of the devices with printed polymeric anode were compared to the one realized depositing DMSO-PEDOT:PSS by spin coating technique. The best cells performances were obtained by UV ozone treatment reaching a power conversion efficiency of 1.5%. (c) 2013 Society of Plastics Engineers