Brush painting of transparent PEDOT/Ag nanowire/PEDOT multilayer electrodes for flexible organic solar cells

We fabricated highly transparent and flexible poly(3,4- ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/Ag nanowire (NW)/PEDOT:PSS (PAP) multilayer electrodes by continuous brush-painting for used as flexible anode in highly flexible organic solar cells (FOSCs). By combining the flexibility of PEDOT:PSS and low resistivity of Ag NWs, we fabricated highly flexible PAP multilayer electrodes with a low sheet resistance of 13.96 Ω/square and a high diffusive transmittance of 80.48%. Effective embedment of the Ag NW network into the conductive PEDOT:PSS layer led to metallic conductivity and a high diffusive transmittance, which are desirable in transparent anodes for FOSCs. In addition, the PAP electrode showed an invariable resistance (ΔR/R₀) during outer and inner bending testing, due to the high strain failure of both PEDOT:PSS and Ag NW network. The identical current density-voltage behavior of the FOSCs with the brush-painted PAP electrode as the FOSC with a conventional ITO electrode demonstrates that the brush-painted PAP multilayer is a promising alternative to high-cost ITO electrodes to produce cost-efficient FOSCs. Furthermore, we suggest that high-performance, transparent, and flexible electrodes can be fabricated by low-cost brush-painting for paintable FOSCs.