The effect of pH on the elechtrochemical over-oxidation of PEDOT:PSS films
2007 (English)In: Solid State Ionics, ISSN 0167-2738, Vol. 177, no 39-40, 3521-3527 p.Article in journal (Refereed) Published
Chemical degradation of conjugated polymers is one cause of material failures in polymer-based (opto)electronic devices, but can also be used as a technique for subtractive patterning of polymer films. When a large anodic potential is applied to the conducting polymer blend poly(3,4-ethylenedioxythiophene)-poly(4styrenesulfonate), PEDOT:PSS, an over-oxidation reaction occurs, altering its electrical conductivity. Here, we have studied the effect of pH on the electrochemical over-oxidation process of PEDOT in PEDOT:PSS. High pH is associated with a decrease of over-oxidation potential and an increase of resistivity in the resulting film. Vibrational spectroscopy and photoelectron spectroscopy measurements on over-oxidized PEDOT:PSS films indicate that the decrease in conductivity results from cleavage of the conjugation pathway accompanied by the formation of sulfone, carbonyl and carboxylic groups in the polymer chain.
Place, publisher, year, edition, pages
ScienceDirect , 2007. Vol. 177, no 39-40, 3521-3527 p.
Poly(3, 4-ethylenedioxythiophene), Degradation, Over-oxidation, XPS, FTIR, Conjugated polymer, Polythiophenes
IdentifiersURN: urn:nbn:se:liu:diva-14026DOI: 10.1016/j.ssi.2006.10.008OAI: oai:DiVA.org:liu-14026DiVA: diva2:22483