Tuning of PEDOT : PSS synthesis via multiple doping for enhanced electrical conductivity

Abstract The poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) synthesis conditions were refined to obtain extremely high electrical conductivity. PEDOT:PSS was synthesized by chemical oxidative polymerization under the effects of acid types and concentrations, EDOT:PSS weight ratio, and surfactant types and concentrations. The PEDOT:PSS synthesized with EDOT:PSS weight ratio of 0.5:5.5 in 0.1 mol L−1 HClO4 provided the highest electrical conductivity of 1.04 × 104 ± 188 S cm−1, not previously reported. The enhanced electrical conductivity can be attributed to the combinatorial primary doping by selective ions (ClO4−, PSS−, SO42−) generating a suitable PEDOT:PSS structure with high carrier number and electron mobility, as consistently verified using Fourier transform infrared spectroscopy, UV–visible spectrometry, X‐ray photoelectron spectrometry and thermogravimetric analysis. The refined synthesis opens a new route for PEDOT:PSS nanoparticles to be used in various electronic applications which require the starting nontoxic organic material to be highly conductive. © 2021 Society of Industrial Chemistry.