Selectively modulated inkjet printing of highly conductive and transparent foldable polymer electrodes for flexible polymer light-emitting diode applications

High efficient flexible polymer light-emitting devices which composed with highly conductive and transparent foldable polymer electrodes were fabricated. New doping materials, n-methyl-2-pyrrolidone (NMP) and n-methylformamide (NMF), have much improved the conductivity of poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS). The selectively modulated inkjet-printing method facilitated the PEDOT: PSS's application to both transparent anodes and highly conductive bus line electrodes. Multiple-time printed PEDOT: PSS electrodes showed a similar performance to Ag bus lines while one-time printed anode showed a much better figure of merit than that of ITO on plastic. Due to the flexible property, high transparency and high work function of the polymeric anode, ITO-free PLEDs showed a high performance with foldable characteristics. (C) 2015 Elsevier B.V. All rights reserved.