title: Structurally-driven Enhancement of Thermoelectric Properties within Poly(3,4-ethylenedioxythiophene) thin Films.
abstract: Due to the rising need for clean energy, thermoelectricity has raised as a potential alternative to reduce dependence on fossil fuels. Specifically, thermoelectric devices based on polymers could offer an efficient path for near-room temperature energy harvesters. Thus, control over thermoelectric properties of conducting polymers is crucial and, herein, the structural, electrical and thermoelectric properties of poly(3,4-ethylenedioxythiophene) (PEDOT) thin films doped with p-toluenesulfonate (Tos) molecules were investigated with regards to thin film processing.
  
  
  
  Tos thin films were prepared by in-situ polymerization of (3,4-ethylenedioxythiophene) monomers in presence of iron(III) p-toluenesulfonate with different co-solvents in order to tune the film structure. While the Seebeck coefficient remained constant, a large improvement in the electrical conductivity was observed for thin films processed with high boiling point additives. The increase of electrical conductivity was found to be solely in-plane mobility-driven. Probing the thin film structure by Grazing Incidence Wide Angle X-ray Scattering has shown that this behavior is dictated by the structural properties of the
  
  
  
  Tos films; specifically by the thin film crystallinity combined to the preferential edge-on orientation of the PEDOT crystallites. Consequentially enhancement of the power factor from 25 to 78.5 μW/mK(2) has been readily obtained for
  
  
  
  Tos thin films following this methodology.
authors.affiliation: Laboratoire de Chimie des Polymères Organiques, CNRS - ENSCPB - Université de Bordeaux - UMR 5629, F-33607 Pessac, France.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Petsagkourakis
authors.affiliation: Laboratoire de Chimie des Polymères Organiques, CNRS - ENSCPB - Université de Bordeaux - UMR 5629, F-33607 Pessac, France.|Bordeaux INP, LCPO, UMR 5629, F-33600, Pessac, France.
authors.forename: Eleni
authors.initials: E
authors.lastname: Pavlopoulou
authors.affiliation: Macromolecular Chemistry &New Polymeric Materials, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Portale
authors.affiliation: Laboratoire Ondes et Matière d'Aquitaine, CNRS - Université de Bordeaux - UMR 5798, F-33400 Talence, France.
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Kuropatwa
authors.affiliation: Laboratoire Ondes et Matière d'Aquitaine, CNRS - Université de Bordeaux - UMR 5798, F-33400 Talence, France.
authors.forename: Stefan
authors.initials: S
authors.lastname: Dilhaire
authors.affiliation: Laboratoire de Chimie des Polymères Organiques, CNRS - ENSCPB - Université de Bordeaux - UMR 5629, F-33607 Pessac, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Fleury
authors.affiliation: Laboratoire de Chimie des Polymères Organiques, CNRS - ENSCPB - Université de Bordeaux - UMR 5629, F-33607 Pessac, France.
authors.forename: Georges
authors.initials: G
authors.lastname: Hadziioannou