Conductivity enhancement of PEDOT/PSS films by solvent vapor treatment

Abstract

Poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT/PSS) is a promising conductive polymer owing to its transparency, the high stability, and high conductivity. Previous studies have reported that the conductivity of PEDOT/PSS films increases on the addition of polar organic solvents to PEDOT/PSS water dispersion prior to film preparation. In this study, we report the conductivity enhancement in PEDOT/PSS films by solvent vapor treatment of the prefabricated film. In addition to dimethylsulfoxide, N,Ndimethylformamide and ethylene glycol, which are known effective additives for enhancing conductivity in PEDOT/PSS films prepared by solvent-addition method, methanol is also effective in enhancing conductivity by solvent vapor treatment. The conductivity of PEDOT/PSS films is enhanced from 5 to 384 S/cm after the solvent vapor treatment by methanol at 35?. In this study, the effect of treatment conditions and the morphological changes after the vapor treatment have been investigated.