Conductivity, morphology, interfacial chemistry, and stability of poly(3,4‐ethylene dioxythiophene)–poly(styrene sulfonate): A photoelectron spectroscopy study

Abstract

X‐ray photoelectron spectroscopy (XPS) has been used to characterize poly(3,4‐ethylene dioxythiophene)–poly(styrene sulfonate) (PEDT/PSS), one of the most common electrically conducting organic polymers. A correlation has been established between the composition, morphology, and polymerization mechanism, on the one hand, and the electric conductivity of PEDT/PSS, on the other hand. XPS has been used to identify interfacial reactions occurring at the polymer‐on‐ITO and polymer‐on‐glass interfaces, as well as chemical changes within the polymer blend induced by electrical stress and exposure to ultraviolet light. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2561–2583, 2003

Electrical characterization of PEDOT:PSS beyond humidity saturation

“…Hence, this favors the hopping of charges between PEDOT chains. By increasing PSS ratio, the distance between PEDOT chains increases, so it leads to higher average hopping distance, and results in decrease of conductivity [30]. The resistivity of the PEDOT-PSS increases due to decreasing interaction between PEDOT chains as a result of swelling of the polymer by the water uptake under high relative humidity.…”

Directly patternable, highly conducting polymers for broad applications in organic electronics

“…Given that PANI is rendered electrically conductive via proton doping while conductive PEDOT is obtained on oxidative doping, it is not surprising that the origin of conductivity enhancement in these systems is different when exposed to DCA. Furthermore, spin casting PEDOT-PSS results in the formation of a thin insulating PSS overlayer (15,22,26). We thus hypothesize that solvent annealing-with DCA being a good solvent for PSS-disrupts this insulating overlayer, effectively enhancing the bulk conductivity of PEDOT-PSS films.…”

“…When commercially available PEDOT that is template synthesized with poly(styrene sulfonic acid), PEDOT-PSS, is exposed to sorbitol (16), dimethylsulfoxide (17), or ethylene glycol (18), for example, its electrical conductivity can be improved by an order of magnitude. Despite such reports, the mechanism by which this conductivity enhancement occurs via exposures to seemingly unrelated solvents remains controversial (14)(15)(16)(17)(18). Elucidation of the origin of conductivity enhancement is further complicated by the fact that these reagents are highly specific to PEDOT-PSS; exposing water-dispersible, polymer acid templated PANI to these reagents does not improve its conductivity.…”

“…Exposing conducting polymers to selective reagents can improve electrical conductivities through a process known as secondary doping (13)(14)(15)(16)(17)(18). When commercially available PEDOT that is template synthesized with poly(styrene sulfonic acid), PEDOT-PSS, is exposed to sorbitol (16), dimethylsulfoxide (17), or ethylene glycol (18), for example, its electrical conductivity can be improved by an order of magnitude.…”

Amphiphilic semiconducting copolymer as compatibility layer for printing polyelectrolyte-gated OFETs

“…4a) gives rise to a high binding energy double peak at (168 -172 eV), originating from the sulfonate group due to the presence of three electronegative oxygen atoms in the surrounding. [20] In the S(2p) narrow scan of the BCtreated PSSH surface (Fig. 4b), the high binding energy peak originates from the PSSH layer while the low binding energy peak (164 -167 eV) originates from the thiophene part of the BC film.…”