An Assessment of the Effect of Synthetic and Doping Conditions on the Processability and Conductivity of Poly(3,4-ethylenedioxythiophene)/Poly(styrene sulfonic acid)

Abstract

Poly(3,4‐ethylenedioxythiophene)/poly(styrene sulfonic acid) (PEDOT/PSS) dispersions are synthesized via conventional oxidative polymerization under various synthetic (reaction times and formulations) and doping conditions (in situ and postpolymerization) with the introduction of dialysis as an additional purification step. Conductivities of films produced from these synthesized dispersions are one to three orders of magnitude higher than the equivalent commercial PEDOT/PSS reference film. In situ doped PEDOT/PSS dispersions give films that are more conductive than those doped postpolymerization. Optimum conductivity of 5.2 ± 0.7 S cm−1 is obtained from PEDOT/PSS dispersions (1:2.5 EDOT:PSS mass ratio) synthesized for 12 h with doping efficiency of 73%. Under these synthetic conditions, the film most likely has the optimal microstructure, i.e., optimal PEDOT chain length and ideal distribution and balance of PEDOT/PSS segments and free PSS chains, favoring charge transport and processability. Capillary electrophoresis is presented here as a novel method for measuring free and doped PSS in PEDOT/PSS dispersions.

Spectroscopic Characterization of Pedot:pss Conducting Polymer by Resonance Raman and Serrs Spectroscopies

“…PEDOT:PSS was synthesized by the chemical method as described elsewhere. 18 Briefly, 144 μL of EDOT and 384 mg Na 2 S 2 O 8 were added to 6% by weight aqueous solution of PSS followed by the addition of 22 mL of deionized water. The synthesis was kept under controlled temperature (23.0 or 30.0 ºC) and vigorous stirring for 12 hours and samples were taken hour by hour for spectroscopic analyses.…”

“…17 In this work PEDOT:PSS was synthesized by the chemical oxidative method. 18 The oxidation and doping of the obtained dispersions were evaluated by RR and SERRS spectroscopy. SERRS spectra of the polymer were recorded on non-capped gold nanoparticles.…”

Intrinsically Stretchable Block Copolymer Based on PEDOT:PSS for Improved Performance in Bioelectronic Applications

“…1,13−15 PEDOT:PSS consists of short chains of PEDOT complexed with longer chains of PSS by coulombic interactions. When cast into a solid film, PEDOT:PSS exhibits conductivity values of 0.1−10 S cm −1 , 16 which is dependent on the ratio of PEDOT to PSS 17 and solid content of the dispersion. 18 Several approaches for enhancing the conductivity and stretchability of PEDOT:PSS have been studied in recent years, 17 reaching conductivity values 18−22 as high as 4380 S cm −1 and fracture strains up to 800%.…”

“…Its transmissivity makes it attractive for photovoltaic applications (e.g., solar cells) − and light-emitting devices, , and it is among the best organic thermoelectric materials. , Moreover, PEDOT:PSS exhibits mixed modes of conductivityelectronic and ionic , which facilitates interactions with biological structures, gaining great interest in organic electrochemical transistors for biosensors. ,− PEDOT:PSS consists of short chains of PEDOT complexed with longer chains of PSS by coulombic interactions. When cast into a solid film, PEDOT:PSS exhibits conductivity values of 0.1–10 S cm –1 , which is dependent on the ratio of PEDOT to PSS and solid content of the dispersion . Several approaches for enhancing the conductivity and stretchability of PEDOT:PSS have been studied in recent years, reaching conductivity values − as high as 4380 S cm –1 and fracture strains up to 800% .…”

“…When cast into a solid film, PEDOT:PSS exhibits conductivity values of 0.1–10 S cm –1 , which is dependent on the ratio of PEDOT to PSS and solid content of the dispersion . Several approaches for enhancing the conductivity and stretchability of PEDOT:PSS have been studied in recent years, reaching conductivity values − as high as 4380 S cm –1 and fracture strains up to 800% . Likewise, the electronic characteristics of PEDOT:PSS can be manipulated by thermal processes (e.g., annealing), exposure to light, blending with an ionic liquid (IL), , or the addition of a strong acid. − …”