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Title: Effect of molecular electrical doping on polyfuran based photovoltaic cells

Abstract

The electronic, optical, and morphological properties of molecularly p-doped polyfuran (PF) films were investigated over a wide range of doping ratio in order to explore the impact of doping in photovoltaic applications. We find evidence for integer-charge transfer between PF and the prototypical molecular p-dopant tetrafluoro-tetracyanoquinodimethane (F4TCNQ) and employed the doped polymer in bilayer organic solar cells using fullerene as acceptor. The conductivity increase in the PF films at dopant loadings ≤2% significantly enhances the short-circuit current of photovoltaic devices. For higher doping ratios, however, F4TCNQ is found to precipitate at the heterojunction between the doped donor polymer and the fullerene acceptor. Ultraviolet photoelectron spectroscopy reveals that its presence acts beneficial to the energy-level alignment by doubling the open-circuit voltage of solar cells from 0.2 V to ca. 0.4 V, as compared to pristine PF.

Authors:
; ;  [1];  [2]; ;  [3];  [1];  [4]
  1. Humboldt-Universität zu Berlin, Institut für Physik and IRIS Adlershof, Brook-Taylor Straße 6, 12489 Berlin (Germany)
  2. Helmholtz-Zentrum für Materialien und Energie GmbH, Bereich Solarenergieforschung, Albert-Einstein-Straße 15, 12489 Berlin (Germany)
  3. Department of Organic Chemistry, Weizmann Institute of Science, 76100 Rehovot (Israel)
  4. (Germany)
Publication Date:
OSTI Identifier:
22402474
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 20; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DOPED MATERIALS; ELECTRICAL PROPERTIES; ENERGY LEVELS; FILMS; FULLERENES; FURANS; HETEROJUNCTIONS; METHANE; OPTICAL PROPERTIES; ORGANIC SOLAR CELLS; PHOTOELECTRON SPECTROSCOPY; PHOTOVOLTAIC EFFECT; POLYMERS; ULTRAVIOLET SPECTRA

Citation Formats

Yu, Shuwen, Opitz, Andreas, Salzmann, Ingo, E-mail: ingo.salzmann@physik.hu-berlin.de, Frisch, Johannes, Cohen, Erez, Bendikov, Michael, Koch, Norbert, and Helmholtz-Zentrum für Materialien und Energie GmbH, Bereich Solarenergieforschung, Albert-Einstein-Straße 15, 12489 Berlin. Effect of molecular electrical doping on polyfuran based photovoltaic cells. United States: N. p., 2015. Web. doi:10.1063/1.4921484.
Yu, Shuwen, Opitz, Andreas, Salzmann, Ingo, E-mail: ingo.salzmann@physik.hu-berlin.de, Frisch, Johannes, Cohen, Erez, Bendikov, Michael, Koch, Norbert, & Helmholtz-Zentrum für Materialien und Energie GmbH, Bereich Solarenergieforschung, Albert-Einstein-Straße 15, 12489 Berlin. Effect of molecular electrical doping on polyfuran based photovoltaic cells. United States. doi:10.1063/1.4921484.
Yu, Shuwen, Opitz, Andreas, Salzmann, Ingo, E-mail: ingo.salzmann@physik.hu-berlin.de, Frisch, Johannes, Cohen, Erez, Bendikov, Michael, Koch, Norbert, and Helmholtz-Zentrum für Materialien und Energie GmbH, Bereich Solarenergieforschung, Albert-Einstein-Straße 15, 12489 Berlin. Mon . "Effect of molecular electrical doping on polyfuran based photovoltaic cells". United States. doi:10.1063/1.4921484.
@article{osti_22402474,
title = {Effect of molecular electrical doping on polyfuran based photovoltaic cells},
author = {Yu, Shuwen and Opitz, Andreas and Salzmann, Ingo, E-mail: ingo.salzmann@physik.hu-berlin.de and Frisch, Johannes and Cohen, Erez and Bendikov, Michael and Koch, Norbert and Helmholtz-Zentrum für Materialien und Energie GmbH, Bereich Solarenergieforschung, Albert-Einstein-Straße 15, 12489 Berlin},
abstractNote = {The electronic, optical, and morphological properties of molecularly p-doped polyfuran (PF) films were investigated over a wide range of doping ratio in order to explore the impact of doping in photovoltaic applications. We find evidence for integer-charge transfer between PF and the prototypical molecular p-dopant tetrafluoro-tetracyanoquinodimethane (F4TCNQ) and employed the doped polymer in bilayer organic solar cells using fullerene as acceptor. The conductivity increase in the PF films at dopant loadings ≤2% significantly enhances the short-circuit current of photovoltaic devices. For higher doping ratios, however, F4TCNQ is found to precipitate at the heterojunction between the doped donor polymer and the fullerene acceptor. Ultraviolet photoelectron spectroscopy reveals that its presence acts beneficial to the energy-level alignment by doubling the open-circuit voltage of solar cells from 0.2 V to ca. 0.4 V, as compared to pristine PF.},
doi = {10.1063/1.4921484},
journal = {Applied Physics Letters},
number = 20,
volume = 106,
place = {United States},
year = {Mon May 18 00:00:00 EDT 2015},
month = {Mon May 18 00:00:00 EDT 2015}
}
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