Enhancement of the thermoelectric properties of PEDOT:PSS thin films by post-treatment

Jinji Luo, Detlef Billep, Thomas Waechtler, Thomas Otto, Marius Toader, Ovidiu Gordan, Evgeniya Sheremet, Joerg Martin, Michael Hietschold, Dietrich R.T. Zahn, Thomas Gessner

Research output: Contribution to journalArticle

141 Citations (Scopus)

Abstract

In this work, the thermoelectric (TE) properties of poly(3,4- ethylenedioxylthiophene):poly(styrene sulfonate) (PEDOT:PSS) thin films at room temperature are studied. Different methods have been applied for tuning the TE properties: 1st addition of polar solvent, dimethyl sulfoxide (DMSO), into the PEDOT:PSS solution; 2nd post-treatment of thin films with a mixture of DMSO and ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4). It is verified that DMSO post-treatment is more efficient than DMSO addition in improving the electrical conductivity with a trivial change in the Seebeck coefficient. The power factor is increased up to 30.1 μW mK-2 for the film with DMSO post-treatment, while the optimized power factor by DMSO addition is 18.2 μW mK-2. It is shown that both DMSO addition and post-treatment induce morphological changes: an interconnected network of elongated PEDOT grains is generated, leading to higher electrical conductivity. In contrast, for those films post-treated in the presence of EMIMBF4, an interconnected network of short and circular PEDOT grains with increased polaron density is created, resulting in the improvement in the Seebeck coefficient and a concomitant compromise in the electrical conductivity. An optimized power factor of 38.46 μW mK -2 is achieved at 50 vol% of EMIMBF4, which is the highest reported so far for PEDOT:PSS thin films to our knowledge. Assuming a thermal conductivity of 0.17 W mK-1, the corresponding ZT is 0.068 at 300 K. These results demonstrate that post-treatment is a promising approach to enhance the TE properties of PEDOT:PSS thin films. Furthermore, ionic liquid, EMIMBF4, shows the potential for tuning the TE properties of PEDOT:PSS thin films via a more environmentally benign process.

Original languageEnglish
Pages (from-to)7576-7583
Number of pages8
JournalJournal of Materials Chemistry A
Volume1
Issue number26
DOIs
Publication statusPublished - 17 Jul 2013
Externally publishedYes

Fingerprint

Styrene
Dimethyl sulfoxide
Dimethyl Sulfoxide
Thin films
Ionic Liquids
Seebeck coefficient
Ionic liquids
Tuning
Gene Conversion
Thermal conductivity
Electric Conductivity

ASJC Scopus subject areas

  • Chemistry(all)
  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)

Cite this

Luo, J., Billep, D., Waechtler, T., Otto, T., Toader, M., Gordan, O., ... Gessner, T. (2013). Enhancement of the thermoelectric properties of PEDOT:PSS thin films by post-treatment. Journal of Materials Chemistry A, 1(26), 7576-7583. https://doi.org/10.1039/c3ta11209h

Enhancement of the thermoelectric properties of PEDOT:PSS thin films by post-treatment. / Luo, Jinji; Billep, Detlef; Waechtler, Thomas; Otto, Thomas; Toader, Marius; Gordan, Ovidiu; Sheremet, Evgeniya; Martin, Joerg; Hietschold, Michael; Zahn, Dietrich R.T.; Gessner, Thomas.

In: Journal of Materials Chemistry A, Vol. 1, No. 26, 17.07.2013, p. 7576-7583.

Research output: Contribution to journalArticle

Luo, J, Billep, D, Waechtler, T, Otto, T, Toader, M, Gordan, O, Sheremet, E, Martin, J, Hietschold, M, Zahn, DRT & Gessner, T 2013, 'Enhancement of the thermoelectric properties of PEDOT:PSS thin films by post-treatment', Journal of Materials Chemistry A, vol. 1, no. 26, pp. 7576-7583. https://doi.org/10.1039/c3ta11209h
Luo, Jinji ; Billep, Detlef ; Waechtler, Thomas ; Otto, Thomas ; Toader, Marius ; Gordan, Ovidiu ; Sheremet, Evgeniya ; Martin, Joerg ; Hietschold, Michael ; Zahn, Dietrich R.T. ; Gessner, Thomas. / Enhancement of the thermoelectric properties of PEDOT:PSS thin films by post-treatment. In: Journal of Materials Chemistry A. 2013 ; Vol. 1, No. 26. pp. 7576-7583.
@article{7c713f794cd545f29f2ccb34a1e45b99,
title = "Enhancement of the thermoelectric properties of PEDOT:PSS thin films by post-treatment",
abstract = "In this work, the thermoelectric (TE) properties of poly(3,4- ethylenedioxylthiophene):poly(styrene sulfonate) (PEDOT:PSS) thin films at room temperature are studied. Different methods have been applied for tuning the TE properties: 1st addition of polar solvent, dimethyl sulfoxide (DMSO), into the PEDOT:PSS solution; 2nd post-treatment of thin films with a mixture of DMSO and ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4). It is verified that DMSO post-treatment is more efficient than DMSO addition in improving the electrical conductivity with a trivial change in the Seebeck coefficient. The power factor is increased up to 30.1 μW mK-2 for the film with DMSO post-treatment, while the optimized power factor by DMSO addition is 18.2 μW mK-2. It is shown that both DMSO addition and post-treatment induce morphological changes: an interconnected network of elongated PEDOT grains is generated, leading to higher electrical conductivity. In contrast, for those films post-treated in the presence of EMIMBF4, an interconnected network of short and circular PEDOT grains with increased polaron density is created, resulting in the improvement in the Seebeck coefficient and a concomitant compromise in the electrical conductivity. An optimized power factor of 38.46 μW mK -2 is achieved at 50 vol{\%} of EMIMBF4, which is the highest reported so far for PEDOT:PSS thin films to our knowledge. Assuming a thermal conductivity of 0.17 W mK-1, the corresponding ZT is 0.068 at 300 K. These results demonstrate that post-treatment is a promising approach to enhance the TE properties of PEDOT:PSS thin films. Furthermore, ionic liquid, EMIMBF4, shows the potential for tuning the TE properties of PEDOT:PSS thin films via a more environmentally benign process.",
author = "Jinji Luo and Detlef Billep and Thomas Waechtler and Thomas Otto and Marius Toader and Ovidiu Gordan and Evgeniya Sheremet and Joerg Martin and Michael Hietschold and Zahn, {Dietrich R.T.} and Thomas Gessner",
year = "2013",
month = "7",
day = "17",
doi = "10.1039/c3ta11209h",
language = "English",
volume = "1",
pages = "7576--7583",
journal = "Journal of Materials Chemistry A",
issn = "2050-7488",
publisher = "Royal Society of Chemistry",
number = "26",

}

TY - JOUR

T1 - Enhancement of the thermoelectric properties of PEDOT:PSS thin films by post-treatment

AU - Luo, Jinji

AU - Billep, Detlef

AU - Waechtler, Thomas

AU - Otto, Thomas

AU - Toader, Marius

AU - Gordan, Ovidiu

AU - Sheremet, Evgeniya

AU - Martin, Joerg

AU - Hietschold, Michael

AU - Zahn, Dietrich R.T.

AU - Gessner, Thomas

PY - 2013/7/17

Y1 - 2013/7/17

N2 - In this work, the thermoelectric (TE) properties of poly(3,4- ethylenedioxylthiophene):poly(styrene sulfonate) (PEDOT:PSS) thin films at room temperature are studied. Different methods have been applied for tuning the TE properties: 1st addition of polar solvent, dimethyl sulfoxide (DMSO), into the PEDOT:PSS solution; 2nd post-treatment of thin films with a mixture of DMSO and ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4). It is verified that DMSO post-treatment is more efficient than DMSO addition in improving the electrical conductivity with a trivial change in the Seebeck coefficient. The power factor is increased up to 30.1 μW mK-2 for the film with DMSO post-treatment, while the optimized power factor by DMSO addition is 18.2 μW mK-2. It is shown that both DMSO addition and post-treatment induce morphological changes: an interconnected network of elongated PEDOT grains is generated, leading to higher electrical conductivity. In contrast, for those films post-treated in the presence of EMIMBF4, an interconnected network of short and circular PEDOT grains with increased polaron density is created, resulting in the improvement in the Seebeck coefficient and a concomitant compromise in the electrical conductivity. An optimized power factor of 38.46 μW mK -2 is achieved at 50 vol% of EMIMBF4, which is the highest reported so far for PEDOT:PSS thin films to our knowledge. Assuming a thermal conductivity of 0.17 W mK-1, the corresponding ZT is 0.068 at 300 K. These results demonstrate that post-treatment is a promising approach to enhance the TE properties of PEDOT:PSS thin films. Furthermore, ionic liquid, EMIMBF4, shows the potential for tuning the TE properties of PEDOT:PSS thin films via a more environmentally benign process.

AB - In this work, the thermoelectric (TE) properties of poly(3,4- ethylenedioxylthiophene):poly(styrene sulfonate) (PEDOT:PSS) thin films at room temperature are studied. Different methods have been applied for tuning the TE properties: 1st addition of polar solvent, dimethyl sulfoxide (DMSO), into the PEDOT:PSS solution; 2nd post-treatment of thin films with a mixture of DMSO and ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4). It is verified that DMSO post-treatment is more efficient than DMSO addition in improving the electrical conductivity with a trivial change in the Seebeck coefficient. The power factor is increased up to 30.1 μW mK-2 for the film with DMSO post-treatment, while the optimized power factor by DMSO addition is 18.2 μW mK-2. It is shown that both DMSO addition and post-treatment induce morphological changes: an interconnected network of elongated PEDOT grains is generated, leading to higher electrical conductivity. In contrast, for those films post-treated in the presence of EMIMBF4, an interconnected network of short and circular PEDOT grains with increased polaron density is created, resulting in the improvement in the Seebeck coefficient and a concomitant compromise in the electrical conductivity. An optimized power factor of 38.46 μW mK -2 is achieved at 50 vol% of EMIMBF4, which is the highest reported so far for PEDOT:PSS thin films to our knowledge. Assuming a thermal conductivity of 0.17 W mK-1, the corresponding ZT is 0.068 at 300 K. These results demonstrate that post-treatment is a promising approach to enhance the TE properties of PEDOT:PSS thin films. Furthermore, ionic liquid, EMIMBF4, shows the potential for tuning the TE properties of PEDOT:PSS thin films via a more environmentally benign process.

UR - http://www.scopus.com/inward/record.url?scp=84880055112&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84880055112&partnerID=8YFLogxK

U2 - 10.1039/c3ta11209h

DO - 10.1039/c3ta11209h

M3 - Article

VL - 1

SP - 7576

EP - 7583

JO - Journal of Materials Chemistry A

JF - Journal of Materials Chemistry A

SN - 2050-7488

IS - 26

ER -