title: Combinatorial screening of inkjet printed ternary blends for organic photovoltaics: absorption behavior and morphology.
abstract: Inkjet printing was used for the preparation of ternary polymer/polymer/fullerene layers for organic solar cell application, as part of a combinatorial setup for the preparation and characterization of thin-film libraries. Poly(phenylene-ethynylene)-alt-poly(phenylene-vinylene) (PPE-alt-PPV) and poly(diketopyrrolopyrrole-alt-fluorene) (P(DPP-alt-F)) were systematically blended with poly(3-octylthiophene) (P3OT) and investigated by UV-vis spectroscopy to improve the photon harvesting by extending the absorption range. The blends with the broadest absorption range (20 and 40 wt % of PPE-alt-PPV and P(DPP-alt-F), respectively) were mixed with mono(1-[3-(methoxycarbonyl)propyl]-1-phenyl)-[6,6]C61 (PCBM). The blend with the low band gap polymer P(DPP-alt-F) revealed the most extended absorption, which ranges over the whole visible spectrum (350 to 750 nm). The mixing with PCBM (ratio 1/3) led to an optimal emission quenching and revealed a smooth film formation. In this contribution, we show that the combinatorial screening using inkjet printing represents an effective, time- and material-saving workflow for the investigation of polymer blend libraries, which is of high interest for the development of new materials for active layers in organic photovoltaics.
authors.affiliation: Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena , Humboldtstraße 10, 07743 Jena, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Teichler
authors.forename: Stefan
authors.initials: S
authors.lastname: Hölzer
authors.forename: Jürgen
authors.initials: J
authors.lastname: Nowotny
authors.forename: Florian
authors.initials: F
authors.lastname: Kretschmer
authors.forename: Cornelia
authors.initials: C
authors.lastname: Bader
authors.forename: Jolke
authors.initials: J
authors.lastname: Perelaer
authors.forename: Martin D
authors.initials: MD
authors.lastname: Hager
authors.forename: Stephanie
authors.initials: S
authors.lastname: Hoeppener
authors.forename: Ulrich S
authors.initials: US
authors.lastname: Schubert
mesh_terms: D020650:Combinatorial Chemistry Techniques; D007281:Ink; D018625:Microscopy, Atomic Force; D010777:Photochemistry / Q000295:instrumentation*; D013056:Spectrophotometry, Ultraviolet