Journal Article

IMPULSE-2020-00034

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Ionic Liquids as Post-Treatment Agents for Simultaneous Improvement of Seebeck Coefficient and Electrical Conductivity in PEDOT:PSS Films

Saxena, N. ; Pretzl, B. ; Lamprecht, X. ; Bießmann, L. ; Yang, D. ; Li, N. ; Bilko, C. ; Bernstorff, S. ; Müller-Buschbaum, P.MLZ*

2019
Soc. Washington, DC

Please use a persistent id in citations: doi:10.1021/acsami.8b21709

Abstract: Ionic liquid (IL) post-treatment for thin filmsof poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) is employed for the simultaneous enhancementof Seebeck coefficients and electrical conductivities.Through systematic variation of the ILs, by changing theanions while keeping the cation unchanged, changes inthermoelectric, spectroscopic, and morphological propertiesare investigated by means of UV−vis spectroscopy andgrazing-incidence wide-angle X-ray scattering (GIWAXS) as afunction of the IL concentration. The simultaneous enhancementin the two important thermoelectric properties isascribed to the binary nature of the ILs, which complementsthat of PEDOT:PSS. The anions of the ILs primarily interactwith the positively charged, conducting PEDOT, while thecations interact with negatively charged insulating PSS.Therefore, post-treatment with ILs allows for primary and secondary doping of PEDOT:PSS at the same time. Differencesin the obtained Seebeck coefficients for the investigated ILs are ascribed to the chemical properties of the anions. Additionally,the choice of the latter has implications on the morphology of the treated PEDOT:PSS films regarding average π−π-stackingdistances of PEDOT chains, PEDOT-to-PSS ratios, and edge-on-to-face-on ratios, influencing charge transport propertiesmacroscopically. A morphological model is presented, highlighting the influence of each IL in comparison with pristinePEDOT:PSS films.

Keyword(s): Energy (1st) ; Chemistry (2nd) ; Soft Condensed Matter (2nd)

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Contributing Institute(s):

1. E13 (E13)
2. Heinz Maier-Leibnitz Zentrum (MLZ)

Experiment(s):

1. No specific instrument

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Engineering, Computing and Technology ; Current Contents - Physical, Chemical and Earth Sciences ; IF >= 5 ; JCR ; NCBI Molecular Biology Database ; SCOPUS ; Science Citation Index ; Science Citation Index Expanded ; Web of Science Core Collection

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