Highly Conductive PEDOT:PSS Films with 1,3‐Dimethyl‐2‐Imidazolidinone as Transparent Electrodes for Organic Light‐Emitting Diodes

Highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PSS) films as transparent electrodes for organic light-emitting diodes (OLEDs) are doped with a new solvent 1,3-dimethyl-2-imidazolidinone (DMI) and are optimized using solvent post-treatment. The DMI dopedPSS films show significantly enhanced conductivities up to 812.1 S cm(-1) . The sheet resistance of thePSS films doped with DMI is further reduced by various solvent post-treatment. The effect of solvent post-treatment on DMI dopedPSS films is investigated and is shown to reduce insulating PSS in the conductive films. The solvent posttreatedPSS films are successfully employed as transparent electrodes in white OLEDs. It is shown that the efficiency of OLEDs with the optimized DMI dopedPSS films is higher than that of reference OLEDs doped with a conventional solvent (ethylene glycol). The results present that the optimizedPSS films with the new solvent of DMI can be a promising transparent electrode for low-cost, efficient ITO-free white OLEDs.