Elucidating the Structure-Function Relationship of Poly(3,4-theylenedioxythiophene) Films to Advance Electrochemical Measurements

Adam R. Meier, William A. Bahureksa, Michael L Heien

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Previous work has demonstrated the utility of poly(3,4-theylenedioxythiophene) (PEDOT) electrodes for electrochemical detection of neurochemicals. Although these electrodes have been implemented successfully, there is minimal data linking redox mechanisms, electron-transfer characteristics, and sensor lifetime to the electrode molecular composition. Common polymer electrodes are made from commercially available PEDOT:polystyrenesulfonate (PEDOT:PSS), which is easily processed but has slow electron-transfer kinetics and short electrochemical lifetimes. Here, we describe vapor-phase synthesized PEDOT:tosylate films that have a higher conductance and a much lower apparent capacitance than PEDOT:PSS (99 ± 8 versus 2390 ± 130 μF/cm2). Additionally, we show that the electron-transfer kinetics and electrochemical lifetime are both improved. To investigate the chemical causes of these improvements we used ultraviolet-visible absorbance and X-ray photoelectron spectroscopy (XPS). We discovered that the high density of PEDOT incorporated into PEDOT:tosylate films coupled with the lack of impurities and replacing the polymeric dopant (PSS) leads to both increased conductance and reduced film capacitance. This is most clearly demonstrated through the doping ratio of 3.80 ± 0.10 in vapor-phase synthesized PEDOT:tosylate versus 0.20 ± 0.02 in PEDOT:PSS. Furthermore, the electrochemical lifetime of the films is dependent upon the amount of PEDOT present. XPS data was used to elucidate the mode of failure of these electrodes. This begins to illuminate the mechanism of electron transfer at conducting polymers electrodes. Understanding both the characteristics that improve the quality of conducting polymer electrodes and the mechanism of electron transfer therein is a crucial step in the wider adaptation of these materials in biosensor applications.

Original languageEnglish (US)
Pages (from-to)21114-21122
Number of pages9
JournalJournal of Physical Chemistry C
Volume120
Issue number37
DOIs
StatePublished - Sep 22 2016

Fingerprint

Electrodes
electrodes
electron transfer
Electrons
life (durability)
Conducting polymers
conducting polymers
Capacitance
X ray photoelectron spectroscopy
capacitance
Vapors
Doping (additives)
photoelectron spectroscopy
vapor phases
Kinetics
kinetics
bioinstrumentation
Biosensors
Polymers
x rays

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Surfaces, Coatings and Films
  • Physical and Theoretical Chemistry

Cite this

Elucidating the Structure-Function Relationship of Poly(3,4-theylenedioxythiophene) Films to Advance Electrochemical Measurements. / Meier, Adam R.; Bahureksa, William A.; Heien, Michael L.

In: Journal of Physical Chemistry C, Vol. 120, No. 37, 22.09.2016, p. 21114-21122.

Research output: Contribution to journalArticle

@article{462b2198b8004a93b177da1264eeb1e3,
title = "Elucidating the Structure-Function Relationship of Poly(3,4-theylenedioxythiophene) Films to Advance Electrochemical Measurements",
abstract = "Previous work has demonstrated the utility of poly(3,4-theylenedioxythiophene) (PEDOT) electrodes for electrochemical detection of neurochemicals. Although these electrodes have been implemented successfully, there is minimal data linking redox mechanisms, electron-transfer characteristics, and sensor lifetime to the electrode molecular composition. Common polymer electrodes are made from commercially available PEDOT:polystyrenesulfonate (PEDOT:PSS), which is easily processed but has slow electron-transfer kinetics and short electrochemical lifetimes. Here, we describe vapor-phase synthesized PEDOT:tosylate films that have a higher conductance and a much lower apparent capacitance than PEDOT:PSS (99 ± 8 versus 2390 ± 130 μF/cm2). Additionally, we show that the electron-transfer kinetics and electrochemical lifetime are both improved. To investigate the chemical causes of these improvements we used ultraviolet-visible absorbance and X-ray photoelectron spectroscopy (XPS). We discovered that the high density of PEDOT incorporated into PEDOT:tosylate films coupled with the lack of impurities and replacing the polymeric dopant (PSS) leads to both increased conductance and reduced film capacitance. This is most clearly demonstrated through the doping ratio of 3.80 ± 0.10 in vapor-phase synthesized PEDOT:tosylate versus 0.20 ± 0.02 in PEDOT:PSS. Furthermore, the electrochemical lifetime of the films is dependent upon the amount of PEDOT present. XPS data was used to elucidate the mode of failure of these electrodes. This begins to illuminate the mechanism of electron transfer at conducting polymers electrodes. Understanding both the characteristics that improve the quality of conducting polymer electrodes and the mechanism of electron transfer therein is a crucial step in the wider adaptation of these materials in biosensor applications.",
author = "Meier, {Adam R.} and Bahureksa, {William A.} and Heien, {Michael L}",
year = "2016",
month = "9",
day = "22",
doi = "10.1021/acs.jpcc.6b04622",
language = "English (US)",
volume = "120",
pages = "21114--21122",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "37",

}

TY - JOUR

T1 - Elucidating the Structure-Function Relationship of Poly(3,4-theylenedioxythiophene) Films to Advance Electrochemical Measurements

AU - Meier, Adam R.

AU - Bahureksa, William A.

AU - Heien, Michael L

PY - 2016/9/22

Y1 - 2016/9/22

N2 - Previous work has demonstrated the utility of poly(3,4-theylenedioxythiophene) (PEDOT) electrodes for electrochemical detection of neurochemicals. Although these electrodes have been implemented successfully, there is minimal data linking redox mechanisms, electron-transfer characteristics, and sensor lifetime to the electrode molecular composition. Common polymer electrodes are made from commercially available PEDOT:polystyrenesulfonate (PEDOT:PSS), which is easily processed but has slow electron-transfer kinetics and short electrochemical lifetimes. Here, we describe vapor-phase synthesized PEDOT:tosylate films that have a higher conductance and a much lower apparent capacitance than PEDOT:PSS (99 ± 8 versus 2390 ± 130 μF/cm2). Additionally, we show that the electron-transfer kinetics and electrochemical lifetime are both improved. To investigate the chemical causes of these improvements we used ultraviolet-visible absorbance and X-ray photoelectron spectroscopy (XPS). We discovered that the high density of PEDOT incorporated into PEDOT:tosylate films coupled with the lack of impurities and replacing the polymeric dopant (PSS) leads to both increased conductance and reduced film capacitance. This is most clearly demonstrated through the doping ratio of 3.80 ± 0.10 in vapor-phase synthesized PEDOT:tosylate versus 0.20 ± 0.02 in PEDOT:PSS. Furthermore, the electrochemical lifetime of the films is dependent upon the amount of PEDOT present. XPS data was used to elucidate the mode of failure of these electrodes. This begins to illuminate the mechanism of electron transfer at conducting polymers electrodes. Understanding both the characteristics that improve the quality of conducting polymer electrodes and the mechanism of electron transfer therein is a crucial step in the wider adaptation of these materials in biosensor applications.

AB - Previous work has demonstrated the utility of poly(3,4-theylenedioxythiophene) (PEDOT) electrodes for electrochemical detection of neurochemicals. Although these electrodes have been implemented successfully, there is minimal data linking redox mechanisms, electron-transfer characteristics, and sensor lifetime to the electrode molecular composition. Common polymer electrodes are made from commercially available PEDOT:polystyrenesulfonate (PEDOT:PSS), which is easily processed but has slow electron-transfer kinetics and short electrochemical lifetimes. Here, we describe vapor-phase synthesized PEDOT:tosylate films that have a higher conductance and a much lower apparent capacitance than PEDOT:PSS (99 ± 8 versus 2390 ± 130 μF/cm2). Additionally, we show that the electron-transfer kinetics and electrochemical lifetime are both improved. To investigate the chemical causes of these improvements we used ultraviolet-visible absorbance and X-ray photoelectron spectroscopy (XPS). We discovered that the high density of PEDOT incorporated into PEDOT:tosylate films coupled with the lack of impurities and replacing the polymeric dopant (PSS) leads to both increased conductance and reduced film capacitance. This is most clearly demonstrated through the doping ratio of 3.80 ± 0.10 in vapor-phase synthesized PEDOT:tosylate versus 0.20 ± 0.02 in PEDOT:PSS. Furthermore, the electrochemical lifetime of the films is dependent upon the amount of PEDOT present. XPS data was used to elucidate the mode of failure of these electrodes. This begins to illuminate the mechanism of electron transfer at conducting polymers electrodes. Understanding both the characteristics that improve the quality of conducting polymer electrodes and the mechanism of electron transfer therein is a crucial step in the wider adaptation of these materials in biosensor applications.

UR - http://www.scopus.com/inward/record.url?scp=84988651829&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84988651829&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.6b04622

DO - 10.1021/acs.jpcc.6b04622

M3 - Article

VL - 120

SP - 21114

EP - 21122

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 37

ER -