Eco-friendly transparent conductive films formed by silver nanowires embedded with conductive polymers in HPMC for flexible OLEDs

In this study, gentianic acid (GtA) was first doped into poly (3,4-ethylenedioxythiophene): poly (styrene-sulfonic) (PEDOT:PSS), and the doped PEDOT:PSS (GP) was spin-coated as a hydrophilic layer on the surface of relatively hydrophobic polyethylene terephthalate (PET) films. After that, silver nanowires (AgNWs) aqueous dispersion and hydroxypropyl methyl cellulose (HPMC) solution were coated over the surface of PET films. Finally, the GP/AgNWs/HPMC flexible conductive films were stripped from the PET surface, achieving a high visible light transmittance (81.5 % at 550 nm) with low sheet resistance (4.2 Ω/□). By embedding AgNWs on the surface of the HPMC film, the surface roughness ( R q) of this flexible transparent conductive film (TCF) was as low as 3.2 nm, meeting the requirements for the fabrication of organic light-emitting diode (OLED) devices. The OLED device fabricated via using this TCF as the anode achieved a maximum brightness ( L max ) of 13,740 cd/m 2 , a maximum current efficiency ( C.E. max ) of 10.6 cd/A, a maximum power efficiency ( P.E. max ) of 5.5 lm/W and a maximum external quantum efficiency ( EQE max ) of 2.9 %. Furthermore, HPMC demonstrated solubility in water at ambient temperature, facilitating the recycling of AgNWS and mitigating environmental pollution. These findings provide a new scope for the application of TCF in recyclable flexible electronic devices.